Add cornernet (#438)

* code for cornernet

* add doc

* refine custom op

* refine code from review comments

* refine doc

* update doc

* update code

* add cornernet_squeeze_mixup_cosine config

* update code

* update code

configs/anchor_free/README.md

+# Anchor Free系列模型
+
+## 内容
+- [简介](#简介)
+- [模型库与基线](#模型库与基线)
+- [算法细节](#算法细节)
+- [如何贡献代码](#如何贡献代码)
+
+## 简介
+目前主流的检测算法大体分为两类： single-stage和two-stage，其中single-stage的经典算法包括SSD, YOLO等，two-stage方法有RCNN系列模型，两大类算法在[PaddleDetection Model Zoo](../MODEL_ZOO.md)中均有给出，它们的共同特点是先定义一系列密集的，大小不等的anchor区域，再基于这些先验区域进行分类和回归，这种方式极大的受限于anchor自身的设计。随着CornerNet的提出，涌现了多种anchor free方法，PaddleDetection也集成了一系列anchor free算法。
+
+## 模型库与基线
+下表中展示了PaddleDetection当前支持的网络结构，具体细节请参考[算法细节](#算法细节)。
+
+|                          | ResNet50  | ResNet50-vd | Hourglass104 |
+|:------------------------:|:--------:|:--------------------------:|:------------------------:|
+| [CornerNet-Squeeze](#CornerNet-Squeeze)  | x        |                          ✓ | ✓                        |
+| [FCOS](#FCOS)  | ✓        |                          x | x                        |
+
+
+### 模型库
+
+#### COCO数据集上的mAP
+
+| 网络结构 | 骨干网络 | 图片个数/GPU | 预训练模型 | mAP | FPS  | 模型下载 |
+|:------------:|:--------:|:----:|:-------:|:-------:|:---------:|:----------:|
+| CornerNet-Squeeze    | Hourglass104 | 14  |    无    | 34.5  | 35.5 | [下载链接](https://paddlemodels.bj.bcebos.com/object_detection/cornernet_squeeze_hg104.tar)  |
+| CornerNet-Squeeze    | ResNet50-vd    | 14  |    [faster\_rcnn\_r50\_vd\_fpn\_2x](https://paddlemodels.bj.bcebos.com/object_detection/faster_rcnn_r50_vd_fpn_2x.tar)    | 32.7     | 42.45      | [下载链接](https://paddlemodels.bj.bcebos.com/object_detection/cornernet_squeeze_r50_vd_fpn.tar) |
+| CornerNet-Squeeze-dcn    | ResNet50-vd    | 14  |    [faster\_rcnn\_dcn\_r50\_vd\_fpn\_2x](https://paddlemodels.bj.bcebos.com/object_detection/faster_rcnn_dcn_r50_vd_fpn_2x.tar)    | 34.9    | 40.05      | [下载链接](https://paddlemodels.bj.bcebos.com/object_detection/cornernet_squeeze_dcn_r50_vd_fpn.tar) |
+| CornerNet-Squeeze-dcn-mixup-cosine*    | ResNet50-vd    | 14  |    [faster\_rcnn\_dcn\_r50\_vd\_fpn\_2x](https://paddlemodels.bj.bcebos.com/object_detection/faster_rcnn_dcn_r50_vd_fpn_2x.tar)    | 38.2    | 40.05      | [下载链接](https://paddlemodels.bj.bcebos.com/object_detection/cornernet_squeeze_dcn_r50_vd_fpn_mixup_cosine.pdparams) |
+| FCOS    | ResNet50    | 2  |    [ResNet50\_cos\_pretrained](https://paddle-imagenet-models-name.bj.bcebos.com/ResNet50_cos_pretrained.tar)    | 39.8 | -      | [下载链接](https://paddlemodels.bj.bcebos.com/object_detection/fcos_r50_fpn_1x.pdparams) |
+| FCOS+multiscale_train    | ResNet50    | 2  |    [ResNet50\_cos\_pretrained](https://paddle-imagenet-models-name.bj.bcebos.com/ResNet50_cos_pretrained.tar)    | 42.0 | -      | [下载链接](https://paddlemodels.bj.bcebos.com/object_detection/fcos_r50_fpn_multiscale_2x.pdparams) |
+
+**注意:**
+
+- 模型FPS在Tesla V100单卡环境中通过tools/eval.py进行测试
+- CornerNet-Squeeze中使用ResNet结构的骨干网络时，加入了FPN结构，骨干网络的输出feature map采用FPN中的P3层输出。
+- \*CornerNet-Squeeze-dcn-mixup-cosine是基于原版CornerNet-Squeeze优化效果最好的模型，在ResNet的骨干网络基础上增加mixup预处理和使用cosine_decay
+- FCOS使用GIoU loss、用location分支预测centerness、左上右下角点偏移量归一化和ground truth中心匹配策略
+
+## 算法细节
+
+### CornerNet-Squeeze
+
+**简介:** [CornerNet-Squeeze](https://arxiv.org/abs/1904.08900) 在[Cornernet](https://arxiv.org/abs/1808.01244)基础上进行改进，预测目标框的左上角和右下角的位置，同时参考SqueezeNet和MobileNet的特点，优化了CornerNet骨干网络Hourglass-104，大幅提升了模型预测速度，相较于原版[YOLO-v3](https://arxiv.org/abs/1804.02767)，在训练精度和推理速度上都具备一定优势。
+
+**特点:**  
+
+- 使用corner_pooling获取候选框左上角和右下角的位置
+- 替换Hourglass-104中的residual block为SqueezeNet中的fire-module
+- 替换第二层3x3卷积为3x3深度可分离卷积
+
+
+### FCOS
+
+**简介:** [FCOS](https://arxiv.org/abs/1904.01355)是一种密集预测的anchor-free检测算法，使用RetinaNet的骨架，直接在feature map上回归目标物体的长宽，并预测物体的类别以及centerness（feature map上像素点离物体中心的偏移程度），centerness最终会作为权重来调整物体得分。
+
+**特点:**  
+
+- 利用FPN结构在不同层预测不同scale的物体框，避免了同一feature map像素点处有多个物体框重叠的情况
+- 通过center-ness单层分支预测当前点是否是目标中心，消除低质量误检
+
+
+## 如何贡献代码
+我们非常欢迎您可以为PaddleDetection中的Anchor Free检测模型提供代码，您可以提交PR供我们review；也十分感谢您的反馈，可以提交相应issue，我们会及时解答。

configs/anchor_free/cornernet_squeeze.yml

+architecture: CornerNetSqueeze
+use_gpu: true
+max_iters: 500000
+log_smooth_window: 20
+log_iter: 20
+save_dir: output
+snapshot_iter: 10000
+metric: COCO
+pretrain_weights: NULL
+weights: output/cornernet_squeeze/model_final
+num_classes: 80
+stack: 2
+
+CornerNetSqueeze:
+  backbone: Hourglass
+  corner_head: CornerHead
+
+Hourglass:
+  dims: [256, 256, 384, 384, 512]
+  modules: [2, 2, 2, 2, 4]
+
+CornerHead:
+  train_batch_size: 14
+  test_batch_size: 1
+  ae_threshold: 0.5
+  num_dets: 100
+  top_k: 20
+
+PostProcess:
+  use_soft_nms: true
+  detections_per_im: 100
+  nms_thresh: 0.001
+  sigma: 0.5
+
+LearningRate:
+  base_lr: 0.00025
+  schedulers:
+  - !PiecewiseDecay
+    gamma: 0.1
+    milestones:
+    - 450000
+
+OptimizerBuilder:
+  optimizer:
+    type: Adam
+  regularizer: NULL
+
+TrainReader:
+  inputs_def:
+    image_shape: [3, 511, 511]
+    fields: ['image', 'im_id', 'gt_bbox', 'gt_class', 'tl_heatmaps', 'br_heatmaps', 'tl_regrs', 'br_regrs', 'tl_tags', 'br_tags', 'tag_masks']
+    output_size: 64
+  dataset:
+    !COCODataSet
+    image_dir: train2017
+    anno_path: annotations/instances_train2017.json
+    dataset_dir:  dataset/coco
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: False
+  - !CornerCrop
+    input_size: 511
+  - !Resize
+    target_dim: 511
+  - !RandomFlipImage
+    prob: 0.5
+  - !CornerRandColor
+    saturation: 0.4
+    contrast: 0.4
+    brightness: 0.4
+  - !Lighting
+    eigval: [0.2141788, 0.01817699, 0.00341571]
+    eigvec: [[-0.58752847, -0.69563484, 0.41340352],
+           [-0.5832747, 0.00994535, -0.81221408],
+           [-0.56089297, 0.71832671, 0.41158938]]
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: False
+    is_channel_first: False
+  - !Permute
+    to_bgr: False
+  - !CornerTarget
+    output_size: [64, 64]
+    num_classes: 80
+  batch_size: 14
+  shuffle: true
+  drop_last: true
+  worker_num: 2
+  use_process: true
+  drop_empty: false
+
+EvalReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !COCODataSet
+      image_dir: val2017
+      anno_path: annotations/instances_val2017.json
+      dataset_dir: dataset/coco
+      with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  batch_size: 1
+  drop_empty: false
+  worker_num: 2
+  use_process: true
+
+TestReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !ImageFolder
+    anno_path: annotations/instances_val2017.json
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  batch_size: 1

configs/anchor_free/cornernet_squeeze_dcn_r50_vd_fpn.yml

+architecture: CornerNetSqueeze
+use_gpu: true
+max_iters: 500000
+log_smooth_window: 20
+log_iter: 20
+save_dir: output
+snapshot_iter: 10000
+metric: COCO
+pretrain_weights: https://paddlemodels.bj.bcebos.com/object_detection/faster_rcnn_dcn_r50_vd_fpn_2x.tar
+weights: output/cornernet_squeeze_dcn_r50_vd_fpn/model_final
+num_classes: 80
+stack: 1
+
+CornerNetSqueeze:
+  backbone: ResNet
+  fpn: FPN
+  corner_head: CornerHead
+
+ResNet:
+  norm_type: bn
+  depth: 50
+  feature_maps: [3, 4, 5]
+  freeze_at: 2
+  variant: d
+  dcn_v2_stages: [3, 4, 5]
+
+FPN:
+  min_level: 3
+  max_level: 6
+  num_chan: 256
+  spatial_scale: [0.03125, 0.0625, 0.125]
+
+CornerHead:
+  train_batch_size: 14
+  test_batch_size: 1
+  ae_threshold: 0.5
+  num_dets: 100
+  top_k: 20
+
+PostProcess:
+  use_soft_nms: true
+  detections_per_im: 100
+  nms_thresh: 0.001
+  sigma: 0.5
+
+LearningRate:
+  base_lr: 0.0005
+  schedulers:
+  - !PiecewiseDecay
+    gamma: 0.1
+    milestones:
+    - 400000
+    - 450000
+  - !LinearWarmup
+    start_factor: 0.
+    steps: 4000
+
+OptimizerBuilder:
+  optimizer:
+    momentum: 0.9
+    type: Momentum
+  regularizer:
+    factor: 0.0005
+    type: L2
+
+TrainReader:
+  inputs_def:
+    image_shape: [3, 511, 511]
+    fields: ['image', 'im_id', 'gt_bbox', 'gt_class', 'tl_heatmaps', 'br_heatmaps', 'tl_regrs', 'br_regrs', 'tl_tags', 'br_tags', 'tag_masks']
+    output_size: 64
+  dataset:
+    !COCODataSet
+    image_dir: train2017
+    anno_path: annotations/instances_train2017.json
+    dataset_dir:  dataset/coco
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: False
+  - !CornerCrop
+    input_size: 511
+  - !Resize
+    target_dim: 511
+  - !RandomFlipImage
+    prob: 0.5
+  - !CornerRandColor
+    saturation: 0.4
+    contrast: 0.4
+    brightness: 0.4
+  - !Lighting
+    eigval: [0.2141788, 0.01817699, 0.00341571]
+    eigvec: [[-0.58752847, -0.69563484, 0.41340352],
+           [-0.5832747, 0.00994535, -0.81221408],
+           [-0.56089297, 0.71832671, 0.41158938]]
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: False
+    is_channel_first: False
+  - !Permute
+    to_bgr: False
+  - !CornerTarget
+    output_size: [64, 64]
+    num_classes: 80
+  batch_size: 14
+  shuffle: true
+  drop_last: true
+  worker_num: 2
+  use_process: true
+  drop_empty: false
+
+EvalReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !COCODataSet
+      image_dir: val2017
+      anno_path: annotations/instances_val2017.json
+      dataset_dir: dataset/coco
+      with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  use_process: true
+  batch_size: 1
+  drop_empty: false
+  worker_num: 2
+
+TestReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !ImageFolder
+    anno_path: annotations/instances_val2017.json
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  batch_size: 1

configs/anchor_free/cornernet_squeeze_dcn_r50_vd_fpn_mixup_cosine.yml

+architecture: CornerNetSqueeze
+use_gpu: true
+max_iters: 500000
+log_smooth_window: 20
+log_iter: 20
+save_dir: output
+snapshot_iter: 10000
+metric: COCO
+pretrain_weights: https://paddlemodels.bj.bcebos.com/object_detection/faster_rcnn_dcn_r50_vd_fpn_2x.tar
+weights: output/cornernet_squeeze_dcn_r50_vd_fpn_mixup_cosine/model_final
+num_classes: 80
+stack: 1
+
+CornerNetSqueeze:
+  backbone: ResNet
+  fpn: FPN
+  corner_head: CornerHead
+
+ResNet:
+  norm_type: bn
+  depth: 50
+  feature_maps: [3, 4, 5]
+  freeze_at: 2
+  variant: d
+  dcn_v2_stages: [3, 4, 5]
+
+FPN:
+  min_level: 3
+  max_level: 6
+  num_chan: 256
+  spatial_scale: [0.03125, 0.0625, 0.125]
+
+CornerHead:
+  train_batch_size: 14
+  test_batch_size: 1
+  ae_threshold: 0.5
+  num_dets: 100
+  top_k: 20
+
+PostProcess:
+  use_soft_nms: true
+  detections_per_im: 100
+  nms_thresh: 0.001
+  sigma: 0.5
+
+LearningRate:
+  base_lr: 0.005
+  schedulers:
+  - !CosineDecay
+    max_iters: 500000
+  - !LinearWarmup
+    start_factor: 0.
+    steps: 4000
+
+OptimizerBuilder:
+  optimizer:
+    momentum: 0.9
+    type: Momentum
+  regularizer:
+    factor: 0.0005
+    type: L2
+
+TrainReader:
+  inputs_def:
+    image_shape: [3, 511, 511]
+    fields: ['image', 'im_id', 'gt_bbox', 'gt_class', 'tl_heatmaps', 'br_heatmaps', 'tl_regrs', 'br_regrs', 'tl_tags', 'br_tags', 'tag_masks']
+    output_size: 64
+    max_tag_len: 256
+  dataset:
+    !COCODataSet
+    image_dir: train2017
+    anno_path: annotations/instances_train2017.json
+    dataset_dir:  dataset/coco
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: False
+    with_mixup: True
+  - !MixupImage
+    alpha: 1.5
+    beta: 1.5
+  - !CornerCrop
+    input_size: 511
+  - !Resize
+    target_dim: 511
+  - !RandomFlipImage
+    prob: 0.5
+  - !CornerRandColor
+    saturation: 0.4
+    contrast: 0.4
+    brightness: 0.4
+  - !Lighting
+    eigval: [0.2141788, 0.01817699, 0.00341571]
+    eigvec: [[-0.58752847, -0.69563484, 0.41340352],
+           [-0.5832747, 0.00994535, -0.81221408],
+           [-0.56089297, 0.71832671, 0.41158938]]
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: False
+    is_channel_first: False
+  - !Permute
+    to_bgr: False
+  - !CornerTarget
+    output_size: [64, 64]
+    num_classes: 80
+    max_tag_len: 256
+  batch_size: 14
+  shuffle: true
+  drop_last: true
+  worker_num: 2
+  use_process: true
+  drop_empty: false
+  mixup_epoch: 200
+
+EvalReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !COCODataSet
+      image_dir: val2017
+      anno_path: annotations/instances_val2017.json
+      dataset_dir: dataset/coco
+      with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  use_process: true
+  batch_size: 1
+  drop_empty: false
+  worker_num: 2
+
+TestReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !ImageFolder
+    anno_path: annotations/instances_val2017.json
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  batch_size: 1

configs/anchor_free/cornernet_squeeze_r50_vd_fpn.yml

+architecture: CornerNetSqueeze
+use_gpu: true
+max_iters: 500000
+log_smooth_window: 20
+log_iter: 20
+save_dir: output
+snapshot_iter: 10000
+metric: COCO
+pretrain_weights: https://paddlemodels.bj.bcebos.com/object_detection/faster_rcnn_dcn_r50_vd_fpn_2x.tar
+weights: output/cornernet_squeeze_r50_vd_fpn/model_final
+num_classes: 80
+stack: 1
+
+CornerNetSqueeze:
+  backbone: ResNet
+  fpn: FPN
+  corner_head: CornerHead
+
+ResNet:
+  norm_type: affine_channel
+  depth: 50
+  feature_maps: [3, 4, 5]
+  freeze_at: 2
+  variant: d
+
+FPN:
+  min_level: 3
+  max_level: 6
+  num_chan: 256
+  spatial_scale: [0.03125, 0.0625, 0.125]
+
+CornerHead:
+  train_batch_size: 14
+  test_batch_size: 1
+  ae_threshold: 0.5
+  num_dets: 100
+  top_k: 20
+
+PostProcess:
+  use_soft_nms: true
+  detections_per_im: 100
+  nms_thresh: 0.001
+  sigma: 0.5
+
+LearningRate:
+  base_lr: 0.0005
+  schedulers:
+  - !PiecewiseDecay
+    gamma: 0.1
+    milestones:
+    - 450000
+
+OptimizerBuilder:
+  optimizer:
+    type: Adam
+  regularizer: NULL
+
+TrainReader:
+  inputs_def:
+    image_shape: [3, 511, 511]
+    fields: ['image', 'im_id', 'gt_bbox', 'gt_class', 'tl_heatmaps', 'br_heatmaps', 'tl_regrs', 'br_regrs', 'tl_tags', 'br_tags', 'tag_masks']
+    output_size: 64
+  dataset:
+    !COCODataSet
+    image_dir: train2017
+    anno_path: annotations/instances_train2017.json
+    dataset_dir:  dataset/coco
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: False
+  - !CornerCrop
+    input_size: 511
+  - !Resize
+    target_dim: 511
+  - !RandomFlipImage
+    prob: 0.5
+  - !CornerRandColor
+    saturation: 0.4
+    contrast: 0.4
+    brightness: 0.4
+  - !Lighting
+    eigval: [0.2141788, 0.01817699, 0.00341571]
+    eigvec: [[-0.58752847, -0.69563484, 0.41340352],
+           [-0.5832747, 0.00994535, -0.81221408],
+           [-0.56089297, 0.71832671, 0.41158938]]
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: False
+    is_channel_first: False
+  - !Permute
+    to_bgr: False
+  - !CornerTarget
+    output_size: [64, 64]
+    num_classes: 80
+  batch_size: 14
+  shuffle: true
+  drop_last: true
+  worker_num: 2
+  use_process: true
+  drop_empty: false
+
+EvalReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !COCODataSet
+      image_dir: val2017
+      anno_path: annotations/instances_val2017.json
+      dataset_dir: dataset/coco
+      with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  use_process: true
+  batch_size: 1
+  drop_empty: false
+  worker_num: 2
+
+TestReader:
+  inputs_def:
+    fields: ['image', 'im_id', 'ratios', 'borders']
+    output_size: 64
+  dataset:
+    !ImageFolder
+    anno_path: annotations/instances_val2017.json
+    with_background: false
+  sample_transforms:
+  - !DecodeImage
+    to_rgb: false
+  - !CornerCrop
+    is_train: false
+  - !CornerRatio
+    input_size: 511
+    output_size: 64
+  - !Permute
+    to_bgr: False
+  - !NormalizeImage
+    mean: [0.40789654, 0.44719302, 0.47026115]
+    std: [0.28863828, 0.27408164, 0.2780983]
+    is_scale: True
+    is_channel_first: True
+  batch_size: 1

docs/MODEL_ZOO.md

@@ -214,3 +214,7 @@ Please refer [face detection models](https://github.com/PaddlePaddle/PaddleDetec
 ### Object Detection in Open Images Dataset V5
 
 Please refer [Open Images Dataset V5 Baseline model](featured_model/OIDV5_BASELINE_MODEL.md) for details.
+
+### Anchor Free Models
+
+Please refer [Anchor Free Models](featured_model/ANCHOR_FREE_DETECTION.md) for details.

docs/MODEL_ZOO_cn.md

@@ -204,3 +204,7 @@ Paddle提供基于ImageNet的骨架网络预训练模型。所有预训练模型
 ### 基于Open Images V5数据集的物体检测
 
 详细请参考[Open Images V5数据集基线模型](featured_model/OIDV5_BASELINE_MODEL.md)。
+
+### Anchor Free系列模型
+
+详细请参考[Anchor Free系列模型](featured_model/ANCHOR_FREE_DETECTION.md)。

docs/featured_model/ANCHOR_FREE_DETECTION.md

+**文档教程请参考：** [ACHOR\_FREE\_DETECTION.md](../../configs/anchor_free/README.md) <br/>

ppdet/data/transform/op_helper.py

@@ -393,3 +393,52 @@ def is_poly(segm):
     assert isinstance(segm, (list, dict)), \
         "Invalid segm type: {}".format(type(segm))
     return isinstance(segm, list)
+
+
+def gaussian_radius(bbox_size, min_overlap):
+    height, width = bbox_size
+
+    a1 = 1
+    b1 = (height + width)
+    c1 = width * height * (1 - min_overlap) / (1 + min_overlap)
+    sq1 = np.sqrt(b1**2 - 4 * a1 * c1)
+    radius1 = (b1 - sq1) / (2 * a1)
+
+    a2 = 4
+    b2 = 2 * (height + width)
+    c2 = (1 - min_overlap) * width * height
+    sq2 = np.sqrt(b2**2 - 4 * a2 * c2)
+    radius2 = (b2 - sq2) / (2 * a2)
+
+    a3 = 4 * min_overlap
+    b3 = -2 * min_overlap * (height + width)
+    c3 = (min_overlap - 1) * width * height
+    sq3 = np.sqrt(b3**2 - 4 * a3 * c3)
+    radius3 = (b3 + sq3) / (2 * a3)
+    return min(radius1, radius2, radius3)
+
+
+def draw_gaussian(heatmap, center, radius, k=1, delte=6):
+    diameter = 2 * radius + 1
+    gaussian = gaussian2D((diameter, diameter), sigma=diameter / delte)
+
+    x, y = center
+
+    height, width = heatmap.shape[0:2]
+
+    left, right = min(x, radius), min(width - x, radius + 1)
+    top, bottom = min(y, radius), min(height - y, radius + 1)
+
+    masked_heatmap = heatmap[y - top:y + bottom, x - left:x + right]
+    masked_gaussian = gaussian[radius - top:radius + bottom, radius - left:
+                               radius + right]
+    np.maximum(masked_heatmap, masked_gaussian * k, out=masked_heatmap)
+
+
+def gaussian2D(shape, sigma=1):
+    m, n = [(ss - 1.) / 2. for ss in shape]
+    y, x = np.ogrid[-m:m + 1, -n:n + 1]
+
+    h = np.exp(-(x * x + y * y) / (2 * sigma * sigma))
+    h[h < np.finfo(h.dtype).eps * h.max()] = 0
+    return h

ppdet/data/transform/operators.py

@@ -42,7 +42,7 @@ from .op_helper import (satisfy_sample_constraint, filter_and_process,
                         generate_sample_bbox, clip_bbox, data_anchor_sampling,
                         satisfy_sample_constraint_coverage, crop_image_sampling,
                         generate_sample_bbox_square, bbox_area_sampling,
-                        is_poly)
+                        is_poly, gaussian_radius, draw_gaussian)
 
 logger = logging.getLogger(__name__)
 
@@ -1243,10 +1243,13 @@ class ColorDistort(BaseOperator):
     def __call__(self, sample, context=None):
         img = sample['image']
         if self.random_apply:
-            distortions = np.random.permutation([
-                self.apply_brightness, self.apply_contrast,
-                self.apply_saturation, self.apply_hue
-            ])
+            functions = [
+                self.apply_brightness,
+                self.apply_contrast,
+                self.apply_saturation,
+                self.apply_hue,
+            ]
+            distortions = np.random.permutation(functions)
             for func in distortions:
                 img = func(img)
             sample['image'] = img
@@ -1266,6 +1269,66 @@ class ColorDistort(BaseOperator):
         return sample
 
 
+@register_op
+class CornerRandColor(ColorDistort):
+    """Random color for CornerNet series models.
+    Args:
+        saturation (float): saturation settings.
+        contrast (float): contrast settings.
+        brightness (float): brightness settings.
+        is_scale (bool): whether to scale the input image.
+    """
+
+    def __init__(self,
+                 saturation=0.4,
+                 contrast=0.4,
+                 brightness=0.4,
+                 is_scale=True):
+        super(CornerRandColor, self).__init__(
+            saturation=saturation, contrast=contrast, brightness=brightness)
+        self.is_scale = is_scale
+
+    def apply_saturation(self, img, img_gray):
+        alpha = 1. + np.random.uniform(
+            low=-self.saturation, high=self.saturation)
+        self._blend(alpha, img, img_gray[:, :, None])
+        return img
+
+    def apply_contrast(self, img, img_gray):
+        alpha = 1. + np.random.uniform(low=-self.contrast, high=self.contrast)
+        img_mean = img_gray.mean()
+        self._blend(alpha, img, img_mean)
+        return img
+
+    def apply_brightness(self, img, img_gray):
+        alpha = 1 + np.random.uniform(
+            low=-self.brightness, high=self.brightness)
+        img *= alpha
+        return img
+
+    def _blend(self, alpha, img, img_mean):
+        img *= alpha
+        img_mean *= (1 - alpha)
+        img += img_mean
+
+    def __call__(self, sample, context=None):
+        img = sample['image']
+        if self.is_scale:
+            img = img.astype(np.float32, copy=False)
+            img /= 255.
+        img_gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
+        functions = [
+            self.apply_brightness,
+            self.apply_contrast,
+            self.apply_saturation,
+        ]
+        distortions = np.random.permutation(functions)
+        for func in distortions:
+            img = func(img, img_gray)
+        sample['image'] = img
+        return sample
+
+
 @register_op
 class NormalizePermute(BaseOperator):
     """Normalize and permute channel order.
@@ -1672,3 +1735,239 @@ class BboxXYXY2XYWH(BaseOperator):
         bbox[:, :2] = bbox[:, :2] + bbox[:, 2:4] / 2.
         sample['gt_bbox'] = bbox
         return sample
+
+
+@register_op
+class Lighting(BaseOperator):
+    """
+    Lighting the imagen by eigenvalues and eigenvectors
+    Args:
+        eigval (list): eigenvalues
+        eigvec (list): eigenvectors
+        alphastd (float): random weight of lighting, 0.1 by default
+    """
+
+    def __init__(self, eigval, eigvec, alphastd=0.1):
+        super(Lighting, self).__init__()
+        self.alphastd = alphastd
+        self.eigval = np.array(eigval).astype('float32')
+        self.eigvec = np.array(eigvec).astype('float32')
+
+    def __call__(self, sample, context=None):
+        alpha = np.random.normal(scale=self.alphastd, size=(3, ))
+        sample['image'] += np.dot(self.eigvec, self.eigval * alpha)
+        return sample
+
+
+@register_op
+class CornerTarget(BaseOperator):
+    """
+    Generate targets for CornerNet by ground truth data. 
+    Args:
+        output_size (int): the size of output heatmaps.
+        num_classes (int): num of classes.
+        gaussian_bump (bool): whether to apply gaussian bump on gt targets.
+            True by default.
+        gaussian_rad (int): radius of gaussian bump. If it is set to -1, the 
+            radius will be calculated by iou. -1 by default.
+        gaussian_iou (float): the threshold iou of predicted bbox to gt bbox. 
+            If the iou is larger than threshold, the predicted bboox seems as
+            positive sample. 0.3 by default
+        max_tag_len (int): max num of gt box per image.
+    """
+
+    def __init__(self,
+                 output_size,
+                 num_classes,
+                 gaussian_bump=True,
+                 gaussian_rad=-1,
+                 gaussian_iou=0.3,
+                 max_tag_len=128):
+        super(CornerTarget, self).__init__()
+        self.num_classes = num_classes
+        self.output_size = output_size
+        self.gaussian_bump = gaussian_bump
+        self.gaussian_rad = gaussian_rad
+        self.gaussian_iou = gaussian_iou
+        self.max_tag_len = max_tag_len
+
+    def __call__(self, sample, context=None):
+        tl_heatmaps = np.zeros(
+            (self.num_classes, self.output_size[0], self.output_size[1]),
+            dtype=np.float32)
+        br_heatmaps = np.zeros(
+            (self.num_classes, self.output_size[0], self.output_size[1]),
+            dtype=np.float32)
+
+        tl_regrs = np.zeros((self.max_tag_len, 2), dtype=np.float32)
+        br_regrs = np.zeros((self.max_tag_len, 2), dtype=np.float32)
+        tl_tags = np.zeros((self.max_tag_len), dtype=np.int64)
+        br_tags = np.zeros((self.max_tag_len), dtype=np.int64)
+        tag_masks = np.zeros((self.max_tag_len), dtype=np.uint8)
+        tag_lens = np.zeros((), dtype=np.int32)
+        tag_nums = np.zeros((1), dtype=np.int32)
+
+        gt_bbox = sample['gt_bbox']
+        gt_class = sample['gt_class']
+        keep_inds  = ((gt_bbox[:, 2] - gt_bbox[:, 0]) > 0) & \
+                ((gt_bbox[:, 3] - gt_bbox[:, 1]) > 0)
+        gt_bbox = gt_bbox[keep_inds]
+        gt_class = gt_class[keep_inds]
+        sample['gt_bbox'] = gt_bbox
+        sample['gt_class'] = gt_class
+        width_ratio = self.output_size[1] / sample['w']
+        height_ratio = self.output_size[0] / sample['h']
+        for i in range(gt_bbox.shape[0]):
+            width = gt_bbox[i][2] - gt_bbox[i][0]
+            height = gt_bbox[i][3] - gt_bbox[i][1]
+
+            xtl, ytl = gt_bbox[i][0], gt_bbox[i][1]
+            xbr, ybr = gt_bbox[i][2], gt_bbox[i][3]
+
+            fxtl = (xtl * width_ratio)
+            fytl = (ytl * height_ratio)
+            fxbr = (xbr * width_ratio)
+            fybr = (ybr * height_ratio)
+
+            xtl = int(fxtl)
+            ytl = int(fytl)
+            xbr = int(fxbr)
+            ybr = int(fybr)
+            if self.gaussian_bump:
+                width = math.ceil(width * width_ratio)
+                height = math.ceil(height * height_ratio)
+                if self.gaussian_rad == -1:
+                    radius = gaussian_radius((height, width), self.gaussian_iou)
+                    radius = max(0, int(radius))
+                else:
+                    radius = self.gaussian_rad
+                draw_gaussian(tl_heatmaps[gt_class[i][0]], [xtl, ytl], radius)
+                draw_gaussian(br_heatmaps[gt_class[i][0]], [xbr, ybr], radius)
+            else:
+                tl_heatmaps[gt_class[i][0], ytl, xtl] = 1
+                br_heatmaps[gt_class[i][0], ybr, xbr] = 1
+
+            tl_regrs[i, :] = [fxtl - xtl, fytl - ytl]
+            br_regrs[i, :] = [fxbr - xbr, fybr - ybr]
+            tl_tags[tag_lens] = ytl * self.output_size[1] + xtl
+            br_tags[tag_lens] = ybr * self.output_size[1] + xbr
+            tag_lens += 1
+
+        tag_masks[:tag_lens] = 1
+
+        sample['tl_heatmaps'] = tl_heatmaps
+        sample['br_heatmaps'] = br_heatmaps
+        sample['tl_regrs'] = tl_regrs
+        sample['br_regrs'] = br_regrs
+        sample['tl_tags'] = tl_tags
+        sample['br_tags'] = br_tags
+        sample['tag_masks'] = tag_masks
+
+        return sample
+
+
+@register_op
+class CornerCrop(BaseOperator):
+    """
+    Random crop for CornerNet
+    Args:
+        random_scales (list): scales of output_size to input_size.
+        border (int): border of corp center
+        is_train (bool): train or test
+        input_size (int): size of input image
+    """
+
+    def __init__(self,
+                 random_scales=[0.6, 0.7, 0.8, 0.9, 1., 1.1, 1.2, 1.3],
+                 border=128,
+                 is_train=True,
+                 input_size=511):
+        super(CornerCrop, self).__init__()
+        self.random_scales = random_scales
+        self.border = border
+        self.is_train = is_train
+        self.input_size = input_size
+
+    def __call__(self, sample, context=None):
+        im_h, im_w = int(sample['h']), int(sample['w'])
+        if self.is_train:
+            scale = np.random.choice(self.random_scales)
+            height = int(self.input_size * scale)
+            width = int(self.input_size * scale)
+
+            w_border = self._get_border(self.border, im_w)
+            h_border = self._get_border(self.border, im_h)
+
+            ctx = np.random.randint(low=w_border, high=im_w - w_border)
+            cty = np.random.randint(low=h_border, high=im_h - h_border)
+
+        else:
+            cty, ctx = im_h // 2, im_w // 2
+            height = im_h | 127
+            width = im_w | 127
+
+        cropped_image = np.zeros(
+            (height, width, 3), dtype=sample['image'].dtype)
+
+        x0, x1 = max(ctx - width // 2, 0), min(ctx + width // 2, im_w)
+        y0, y1 = max(cty - height // 2, 0), min(cty + height // 2, im_h)
+
+        left_w, right_w = ctx - x0, x1 - ctx
+        top_h, bottom_h = cty - y0, y1 - cty
+
+        # crop image
+        cropped_ctx, cropped_cty = width // 2, height // 2
+        x_slice = slice(int(cropped_ctx - left_w), int(cropped_ctx + right_w))
+        y_slice = slice(int(cropped_cty - top_h), int(cropped_cty + bottom_h))
+        cropped_image[y_slice, x_slice, :] = sample['image'][y0:y1, x0:x1, :]
+
+        sample['image'] = cropped_image
+        sample['h'], sample['w'] = height, width
+
+        if self.is_train:
+            # crop detections
+            gt_bbox = sample['gt_bbox']
+            gt_bbox[:, 0:4:2] -= x0
+            gt_bbox[:, 1:4:2] -= y0
+            gt_bbox[:, 0:4:2] += cropped_ctx - left_w
+            gt_bbox[:, 1:4:2] += cropped_cty - top_h
+        else:
+            sample['borders'] = np.array(
+                [
+                    cropped_cty - top_h, cropped_cty + bottom_h,
+                    cropped_ctx - left_w, cropped_ctx + right_w
+                ],
+                dtype=np.float32)
+
+        return sample
+
+    def _get_border(self, border, size):
+        i = 1
+        while size - border // i <= border // i:
+            i *= 2
+        return border // i
+
+
+@register_op
+class CornerRatio(BaseOperator):
+    """
+    Ratio of output size to image size
+    Args:
+        input_size (int): the size of input size
+        output_size (int): the size of heatmap
+    """
+
+    def __init__(self, input_size=511, output_size=64):
+        super(CornerRatio, self).__init__()
+        self.input_size = input_size
+        self.output_size = output_size
+
+    def __call__(self, sample, context=None):
+        scale = (self.input_size + 1) // self.output_size
+        out_height, out_width = (sample['h'] + 1) // scale, (
+            sample['w'] + 1) // scale
+        height_ratio = out_height / float(sample['h'])
+        width_ratio = out_width / float(sample['w'])
+        sample['ratios'] = np.array([height_ratio, width_ratio])
+
+        return sample

ppdet/ext_op/README.md

+# 自定义OP的编译过程
+
+**注意：** 编译自定义OP使用的gcc版本须与Paddle编译使用gcc版本一致，Paddle develop每日版本目前采用**gcc 4.8.2**版本编译，若使用每日版本，请使用**gcc 4.8.2**版本编译自定义OP，否则可能出现兼容性问题。
+
+## 代码结构
+
+  - src: 扩展OP C++/CUDA 源码
+  - cornerpool_lib.py: Python API封装
+  - tests: 各OP单测程序
+
+
+## 编译自定义OP
+
+自定义op需要将实现的C++、CUDA代码编译成动态库，```src/mask.sh```中通过g++/nvcc编译，当然您也可以写Makefile或者CMake。
+
+编译需要include PaddlePaddle的相关头文件，链接PaddlePaddle的lib库。 头文件和lib库可通过下面命令获取到:
+
+```
+# python
+>>> import paddle
+>>> print(paddle.sysconfig.get_include())
+/paddle/pyenv/local/lib/python2.7/site-packages/paddle/include
+>>> print(paddle.sysconfig.get_lib())
+/paddle/pyenv/local/lib/python2.7/site-packages/paddle/libs
+```
+
+我们提供动态库编译脚本如下：
+
+```
+cd src
+sh make.sh
+```
+
+最终编译会产出`cornerpool_lib.so`
+
+**说明：** 若使用源码编译安装PaddlePaddle的方式，编译过程中`cmake`未设置`WITH_MKLDNN`的方式，
+编译自定义OP时会报错找不到`mkldnn.h`等文件，可在`make.sh`中删除编译命令中的`-DPADDLE_WITH_MKLDNN`选项。
+
+
+## 执行单测
+
+执行下列单测，确保自定义算子可在网络中正确使用：
+
+```
+# 回到 ext_op 目录，添加 PYTHONPATH
+cd ..
+export PYTHONPATH=$PYTHONPATH:`pwd`
+
+# 运行单测
+python test/test_corner_op.py
+```
+
+单测运行成功会输出提示信息，如下所示：
+
+```
+.
+----------------------------------------------------------------------
+Ran 4 test in 2.858s
+
+OK
+```
+
+更多关于如何在框架外部自定义 C++ OP，可阅读[官网说明文档](https://www.paddlepaddle.org.cn/documentation/docs/zh/advanced_usage/index_cn.html)

ppdet/ext_op/__init__.py

+#  Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
+#
+#Licensed under the Apache License, Version 2.0 (the "License");
+#you may not use this file except in compliance with the License.
+#You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+#Unless required by applicable law or agreed to in writing, software
+#distributed under the License is distributed on an "AS IS" BASIS,
+#WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#See the License for the specific language governing permissions and
+#limitations under the License.
+
+from . import cornerpool_lib
+from .cornerpool_lib import *
+
+__all__ = cornerpool_lib.__all__

ppdet/ext_op/cornerpool_lib.py

+import os
+import paddle.fluid as fluid
+
+file_dir = os.path.dirname(os.path.abspath(__file__))
+fluid.load_op_library(os.path.join(file_dir, 'src/cornerpool_lib.so'))
+
+from paddle.fluid.layer_helper import LayerHelper
+
+__all__ = [
+    'bottom_pool',
+    'top_pool',
+    'right_pool',
+    'left_pool',
+]
+
+
+def bottom_pool(input, is_test=False, name=None):
+    """
+    This layer calculates the bottom pooling output based on the input.
+    Scan the input from top to bottm for the vertical max-pooling.
+    The output has the same shape with input.
+    Args:
+        input(Variable): This input is a Tensor with shape [N, C, H, W].
+            The data type is float32 or float64.
+    Returns:
+        Variable(Tensor): The output of bottom_pool, with shape [N, C, H, W].
+        The data type is float32 or float64.
+    Examples:
+        ..code-block:: python
+            import paddle.fluid as fluid
+            import cornerpool_lib
+            input = fluid.data(
+                name='input', shape=[2, 64, 10, 10], dtype='float32')
+            output = corner_pool.bottom_pool(input)
+    """
+    if is_test:
+        helper = LayerHelper('bottom_pool', **locals())
+        dtype = helper.input_dtype()
+        output = helper.create_variable_for_type_inference(dtype)
+        max_map = helper.create_variable_for_type_inference(dtype)
+        helper.append_op(
+            type="bottom_pool",
+            inputs={"X": input},
+            outputs={"Output": output,
+                     "MaxMap": max_map})
+        return output
+    H = input.shape[2]
+    i = 1
+    output = input
+    while i < H:
+        cur = output[:, :, i:, :]
+        next = output[:, :, :H - i, :]
+        max_v = fluid.layers.elementwise_max(cur, next)
+        output = fluid.layers.concat([output[:, :, :i, :], max_v], axis=2)
+        i *= 2
+
+    return output
+
+
+def top_pool(input, is_test=False, name=None):
+    """
+    This layer calculates the top pooling output based on the input.
+    Scan the input from bottom to top for the vertical max-pooling.
+    The output has the same shape with input.
+    Args:
+        input(Variable): This input is a Tensor with shape [N, C, H, W].
+            The data type is float32 or float64.
+    Returns:
+        Variable(Tensor): The output of top_pool, with shape [N, C, H, W].
+        The data type is float32 or float64.
+    Examples:
+        ..code-block:: python
+            import paddle.fluid as fluid
+            import cornerpool_lib
+            input = fluid.data(
+                name='input', shape=[2, 64, 10, 10], dtype='float32')
+            output = corner_pool.top_pool(input)
+    """
+    if is_test:
+        helper = LayerHelper('top_pool', **locals())
+        dtype = helper.input_dtype()
+        output = helper.create_variable_for_type_inference(dtype)
+        max_map = helper.create_variable_for_type_inference(dtype)
+        helper.append_op(
+            type="top_pool",
+            inputs={"X": input},
+            outputs={"Output": output,
+                     "MaxMap": max_map})
+        return output
+
+    H = input.shape[2]
+    i = 1
+    output = input
+    while i < H:
+        cur = output[:, :, :H - i, :]
+        next = output[:, :, i:, :]
+        max_v = fluid.layers.elementwise_max(cur, next)
+        output = fluid.layers.concat([max_v, output[:, :, H - i:, :]], axis=2)
+        i *= 2
+
+    return output
+
+
+def right_pool(input, is_test=False, name=None):
+    """
+    This layer calculates the right pooling output based on the input.
+    Scan the input from left to right for the horizontal max-pooling.
+    The output has the same shape with input.
+    Args:
+        input(Variable): This input is a Tensor with shape [N, C, H, W].
+            The data type is float32 or float64.
+    Returns:
+        Variable(Tensor): The output of right_pool, with shape [N, C, H, W].
+        The data type is float32 or float64.
+    Examples:
+        ..code-block:: python
+            import paddle.fluid as fluid
+            import cornerpool_lib
+            input = fluid.data(
+                name='input', shape=[2, 64, 10, 10], dtype='float32')
+            output = corner_pool.right_pool(input)
+    """
+    if is_test:
+        helper = LayerHelper('right_pool', **locals())
+        dtype = helper.input_dtype()
+        output = helper.create_variable_for_type_inference(dtype)
+        max_map = helper.create_variable_for_type_inference(dtype)
+        helper.append_op(
+            type="right_pool",
+            inputs={"X": input},
+            outputs={"Output": output,
+                     "MaxMap": max_map})
+        return output
+
+    W = input.shape[3]
+    i = 1
+    output = input
+    while i < W:
+        cur = output[:, :, :, i:]
+        next = output[:, :, :, :W - i]
+        max_v = fluid.layers.elementwise_max(cur, next)
+        output = fluid.layers.concat([output[:, :, :, :i], max_v], axis=-1)
+        i *= 2
+
+    return output
+
+
+def left_pool(input, is_test=False, name=None):
+    """
+    This layer calculates the left pooling output based on the input.
+    Scan the input from right to left for the horizontal max-pooling.
+    The output has the same shape with input.
+    Args:
+        input(Variable): This input is a Tensor with shape [N, C, H, W].
+            The data type is float32 or float64.
+    Returns:
+        Variable(Tensor): The output of left_pool, with shape [N, C, H, W].
+        The data type is float32 or float64.
+    Examples:
+        ..code-block:: python
+            import paddle.fluid as fluid
+            import cornerpool_lib
+            input = fluid.data(
+                name='input', shape=[2, 64, 10, 10], dtype='float32')
+            output = corner_pool.left_pool(input)
+    """
+    if is_test:
+        helper = LayerHelper('left_pool', **locals())
+        dtype = helper.input_dtype()
+        output = helper.create_variable_for_type_inference(dtype)
+        max_map = helper.create_variable_for_type_inference(dtype)
+        helper.append_op(
+            type="left_pool",
+            inputs={"X": input},
+            outputs={"Output": output,
+                     "MaxMap": max_map})
+        return output
+
+    W = input.shape[3]
+    i = 1
+    output = input
+    while i < W:
+        cur = output[:, :, :, :W - i]
+        next = output[:, :, :, i:]
+        max_v = fluid.layers.elementwise_max(cur, next)
+        output = fluid.layers.concat([max_v, output[:, :, :, W - i:]], axis=-1)
+        i *= 2
+
+    return output

ppdet/ext_op/src/bottom_pool_op.cc

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+class BottomPoolOp : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    ctx->ShareDim("X", /*->*/ "MaxMap");
+    ctx->ShareDim("X", /*->*/ "Output");
+  }
+
+protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(ctx.Input<Tensor>("X")->type(),
+                                   ctx.GetPlace());
+  }
+};
+
+class BottomPoolOpMaker : public framework::OpProtoAndCheckerMaker {
+public:
+  void Make() override {
+    AddInput("X",
+             "Input with shape (batch, C, H, W)");
+    AddOutput("MaxMap", "Max map with index of maximum value of input");
+    AddOutput("Output", "output with same shape as input(X)");
+    AddComment(
+        R"Doc(
+This operatio calculates the bottom pooling output based on the input.
+Scan the input from top to bottom for the vertical max-pooling.
+The output has the same shape with input.
+        )Doc");
+  }
+};
+
+class BottomPoolOpGrad : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+protected:
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput("MaxMap"), "Input(MaxMap) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput(framework::GradVarName("Output")),
+                   "Input(Output@GRAD) should not be null");
+    auto out_grad_name = framework::GradVarName("Output");
+    ctx->ShareDim(out_grad_name, framework::GradVarName("X"));
+  }
+
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        ctx.Input<Tensor>(framework::GradVarName("Output"))->type(),
+        ctx.GetPlace());
+  }
+};
+
+template <typename T>
+class BottomPoolGradDescMaker : public framework::SingleGradOpMaker<T> {
+public:
+  using framework::SingleGradOpMaker<T>::SingleGradOpMaker;
+
+protected:
+  void Apply(GradOpPtr<T> op) const override {
+    op->SetType("bottom_pool_grad");
+    op->SetInput("X", this->Input("X"));
+    op->SetInput(framework::GradVarName("Output"), this->OutputGrad("Output"));
+    op->SetInput("MaxMap", this->Output("MaxMap"));
+    op->SetOutput(framework::GradVarName("X"), this->InputGrad("X"));
+    op->SetAttrMap(this->Attrs());
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OPERATOR(bottom_pool,
+                  ops::BottomPoolOp,
+                  ops::BottomPoolOpMaker,
+                  ops::BottomPoolGradDescMaker<paddle::framework::OpDesc>,
+                  ops::BottomPoolGradDescMaker<paddle::imperative::OpBase>);
+REGISTER_OPERATOR(bottom_pool_grad, ops::BottomPoolOpGrad);

ppdet/ext_op/src/bottom_pool_op.cu

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+#include "paddle/fluid/platform/cuda_primitives.h"
+#include "paddle/fluid/memory/memory.h"
+#include <vector>
+#include "util.cu.h"
+
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+static constexpr int kNumCUDAThreads = 512;
+static constexpr int kNumMaximumNumBlocks = 4096;
+
+static inline int NumBlocks(const int N) {
+  return std::min((N + kNumCUDAThreads - 1) / kNumCUDAThreads,
+                  kNumMaximumNumBlocks);
+}
+
+template <typename T>
+class BottomPoolOpCUDAKernel : public framework::OpKernel<T> {
+public:
+  void Compute(const framework::ExecutionContext &ctx) const override {
+    PADDLE_ENFORCE(platform::is_gpu_place(ctx.GetPlace()),
+                   "This kernel only runs on GPU device.");
+    auto *x = ctx.Input<Tensor>("X");
+    auto *max_map = ctx.Output<Tensor>("MaxMap");
+    auto *output = ctx.Output<Tensor>("Output");
+    auto *x_data = x->data<T>();
+    auto x_dims = x->dims();
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int num = x->numel();
+    auto& dev_ctx = ctx.cuda_device_context();
+
+    int *max_map_data = max_map->mutable_data<int>(x_dims, dev_ctx.GetPlace());
+    T *output_data = output->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+
+    int threads = kNumCUDAThreads;
+    int blocks = NumBlocks(num / height);
+  
+    auto max_val_ptr = memory::Alloc(gpu_place, num / height * sizeof(T));
+    T* max_val_data = reinterpret_cast<T*>(max_val_ptr->ptr());
+    auto max_ind_ptr = memory::Alloc(gpu_place, num / height * sizeof(int));
+    int* max_ind_data = reinterpret_cast<int*>(max_ind_ptr->ptr());
+
+    GetMaxInfo<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), NC_num, height, width, 2, false, max_val_data, max_ind_data, max_map_data);
+
+    blocks = NumBlocks(num);
+    ScatterAddFw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), max_map_data, NC_num, height, width, 2, output_data);
+  }
+};
+
+template <typename T>
+class BottomPoolGradOpCUDAKernel : public framework::OpKernel<T> {
+ public:
+  void Compute(const framework::ExecutionContext& ctx) const override {
+    auto* x = ctx.Input<Tensor>("X");
+    auto* max_map = ctx.Input<Tensor>("MaxMap");
+    auto* out_grad = ctx.Input<Tensor>(framework::GradVarName("Output"));
+    auto* in_grad = ctx.Output<Tensor>(framework::GradVarName("X"));
+    auto x_dims = x->dims();
+    
+    auto& dev_ctx = ctx.cuda_device_context();
+    T* in_grad_data = in_grad->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int grad_num = in_grad->numel();
+    int blocks = NumBlocks(grad_num);
+    FillConstant<T><<<blocks, threads, 0, dev_ctx.stream()>>>(in_grad_data, 0, grad_num);
+
+    ScatterAddBw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(out_grad->data<T>(), max_map->data<int>(), NC_num, height, width, 2, in_grad_data);
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OP_CUDA_KERNEL(bottom_pool,
+                        ops::BottomPoolOpCUDAKernel<float>,
+                        ops::BottomPoolOpCUDAKernel<double>);
+REGISTER_OP_CUDA_KERNEL(bottom_pool_grad,
+                        ops::BottomPoolGradOpCUDAKernel<float>,
+                        ops::BottomPoolGradOpCUDAKernel<double>);

ppdet/ext_op/src/left_pool_op.cc

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+class LeftPoolOp : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    ctx->ShareDim("X", /*->*/ "MaxMap");
+    ctx->ShareDim("X", /*->*/ "Output");
+  }
+
+protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(ctx.Input<Tensor>("X")->type(),
+                                   ctx.GetPlace());
+  }
+};
+
+class LeftPoolOpMaker : public framework::OpProtoAndCheckerMaker {
+public:
+  void Make() override {
+    AddInput("X",
+             "Input with shape (batch, C, H, W)");
+    AddOutput("MaxMap", "Max map with index of maximum value of input");
+    AddOutput("Output", "output with same shape as input(X)");
+    AddComment(
+        R"Doc(
+This operatio calculates the left pooling output based on the input.
+Scan the input from right to left for the horizontal max-pooling.
+The output has the same shape with input.
+        )Doc");
+  }
+};
+
+class LeftPoolOpGrad : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+protected:
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput("MaxMap"), "Input(MaxMap) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput(framework::GradVarName("Output")),
+                   "Input(Output@GRAD) should not be null");
+    auto out_grad_name = framework::GradVarName("Output");
+    ctx->ShareDim(out_grad_name, framework::GradVarName("X"));
+  }
+
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        ctx.Input<Tensor>(framework::GradVarName("Output"))->type(),
+        ctx.GetPlace());
+  }
+};
+
+template <typename T>
+class LeftPoolGradDescMaker : public framework::SingleGradOpMaker<T> {
+public:
+  using framework::SingleGradOpMaker<T>::SingleGradOpMaker;
+
+protected:
+  void Apply(GradOpPtr<T> op) const override {
+    op->SetType("left_pool_grad");
+    op->SetInput("X", this->Input("X"));
+    op->SetInput(framework::GradVarName("Output"), this->OutputGrad("Output"));
+    op->SetInput("MaxMap", this->Output("MaxMap"));
+    op->SetOutput(framework::GradVarName("X"), this->InputGrad("X"));
+    op->SetAttrMap(this->Attrs());
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OPERATOR(left_pool,
+                  ops::LeftPoolOp,
+                  ops::LeftPoolOpMaker,
+                  ops::LeftPoolGradDescMaker<paddle::framework::OpDesc>,
+                  ops::LeftPoolGradDescMaker<paddle::imperative::OpBase>);
+REGISTER_OPERATOR(left_pool_grad, ops::LeftPoolOpGrad);

ppdet/ext_op/src/left_pool_op.cu

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+#include "paddle/fluid/platform/cuda_primitives.h"
+#include "paddle/fluid/memory/memory.h"
+#include <vector>
+#include "util.cu.h"
+
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+static constexpr int kNumCUDAThreads = 512;
+static constexpr int kNumMaximumNumBlocks = 4096;
+
+static inline int NumBlocks(const int N) {
+  return std::min((N + kNumCUDAThreads - 1) / kNumCUDAThreads,
+                  kNumMaximumNumBlocks);
+}
+
+template <typename T>
+class LeftPoolOpCUDAKernel : public framework::OpKernel<T> {
+public:
+  void Compute(const framework::ExecutionContext &ctx) const override {
+    PADDLE_ENFORCE(platform::is_gpu_place(ctx.GetPlace()),
+                   "This kernel only runs on GPU device.");
+    auto *x = ctx.Input<Tensor>("X");
+    auto *max_map = ctx.Output<Tensor>("MaxMap");
+    auto *output = ctx.Output<Tensor>("Output");
+    auto *x_data = x->data<T>();
+    auto x_dims = x->dims();
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int num = x->numel();
+    auto& dev_ctx = ctx.cuda_device_context();
+
+    int *max_map_data = max_map->mutable_data<int>(x_dims, dev_ctx.GetPlace());
+    T *output_data = output->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int blocks = NumBlocks(num / width);
+
+    auto max_val_ptr = memory::Alloc(gpu_place, num / width * sizeof(T));
+    T* max_val_data = reinterpret_cast<T*>(max_val_ptr->ptr());
+    auto max_ind_ptr = memory::Alloc(gpu_place, num / width * sizeof(int));
+    int* max_ind_data = reinterpret_cast<int*>(max_ind_ptr->ptr());
+
+    GetMaxInfo<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), NC_num, height, width, 3, true, max_val_data, max_ind_data, max_map_data);
+
+    blocks = NumBlocks(num);
+    ScatterAddFw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), max_map_data, NC_num, height, width, 3, output_data);
+
+  }
+};
+
+template <typename T>
+class LeftPoolGradOpCUDAKernel : public framework::OpKernel<T> {
+ public:
+  void Compute(const framework::ExecutionContext& ctx) const override {
+    auto* x = ctx.Input<Tensor>("X");
+    auto* max_map = ctx.Input<Tensor>("MaxMap");
+    auto* out_grad = ctx.Input<Tensor>(framework::GradVarName("Output"));
+    auto* in_grad = ctx.Output<Tensor>(framework::GradVarName("X"));
+    auto x_dims = x->dims();
+    
+    auto& dev_ctx = ctx.cuda_device_context();
+    T* in_grad_data = in_grad->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2]; 
+    int width = x_dims[3];
+    int grad_num = in_grad->numel();
+    int blocks = NumBlocks(grad_num);
+    FillConstant<T><<<blocks, threads, 0, dev_ctx.stream()>>>(in_grad_data, 0, grad_num);
+
+    ScatterAddBw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(out_grad->data<T>(), max_map->data<int>(), NC_num, height, width, 3, in_grad_data);
+  }
+};
+
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OP_CUDA_KERNEL(left_pool,
+                        ops::LeftPoolOpCUDAKernel<float>,
+                        ops::LeftPoolOpCUDAKernel<double>);
+REGISTER_OP_CUDA_KERNEL(left_pool_grad,
+                        ops::LeftPoolGradOpCUDAKernel<float>,
+                        ops::LeftPoolGradOpCUDAKernel<double>);

ppdet/ext_op/src/make.sh

+include_dir=$( python -c 'import paddle; print(paddle.sysconfig.get_include())' )
+lib_dir=$( python -c 'import paddle; print(paddle.sysconfig.get_lib())' )
+
+echo $include_dir
+echo $lib_dir
+
+OPS='bottom_pool_op top_pool_op right_pool_op left_pool_op'
+for op in ${OPS}
+do
+nvcc ${op}.cu -c -o ${op}.cu.o -ccbin cc -DPADDLE_WITH_CUDA -DEIGEN_USE_GPU -DPADDLE_USE_DSO -DPADDLE_WITH_MKLDNN -Xcompiler -fPIC -std=c++11 -Xcompiler -fPIC -w --expt-relaxed-constexpr -O0 -g -DNVCC \
+    -I ${include_dir}/third_party/ \
+    -I ${include_dir}
+done
+
+g++ bottom_pool_op.cc bottom_pool_op.cu.o top_pool_op.cc top_pool_op.cu.o right_pool_op.cc right_pool_op.cu.o left_pool_op.cc left_pool_op.cu.o -o cornerpool_lib.so -DPADDLE_WITH_MKLDNN -shared -fPIC -std=c++11 -O0 -g \
+  -I ${include_dir}/third_party/ \
+  -I ${include_dir} \
+  -L ${lib_dir} \
+  -L /usr/local/cuda/lib64 -lpaddle_framework -lcudart
+
+rm *.cu.o
+
+export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$lib_dir

ppdet/ext_op/src/right_pool_op.cc

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+class RightPoolOp : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    ctx->ShareDim("X", /*->*/ "MaxMap");
+    ctx->ShareDim("X", /*->*/ "Output");
+  }
+
+protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(ctx.Input<Tensor>("X")->type(),
+                                   ctx.GetPlace());
+  }
+};
+
+class RightPoolOpMaker : public framework::OpProtoAndCheckerMaker {
+public:
+  void Make() override {
+    AddInput("X",
+             "Input with shape (batch, C, H, W)");
+    AddOutput("MaxMap", "Max map with index of maximum value of input"); 
+    AddOutput("Output", "output with same shape as input(X)");
+    AddComment(
+        R"Doc(
+This operatio calculates the right pooling output based on the input.
+Scan the input from left to right or the horizontal max-pooling.
+The output has the same shape with input.        
+        )Doc");
+  }
+};
+
+class RightPoolOpGrad : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+protected:
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput("MaxMap"), "Input(MaxMap) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput(framework::GradVarName("Output")),
+                   "Input(Output@GRAD) should not be null");
+    auto out_grad_name = framework::GradVarName("Output");
+    ctx->ShareDim(out_grad_name, framework::GradVarName("X"));
+  }
+
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        ctx.Input<Tensor>(framework::GradVarName("Output"))->type(),
+        ctx.GetPlace());
+  }
+};
+
+template <typename T>
+class RightPoolGradDescMaker : public framework::SingleGradOpMaker<T> {
+public:
+  using framework::SingleGradOpMaker<T>::SingleGradOpMaker;
+
+protected:
+  void Apply(GradOpPtr<T> op) const override {
+    op->SetType("right_pool_grad");
+    op->SetInput("X", this->Input("X"));
+    op->SetInput(framework::GradVarName("Output"), this->OutputGrad("Output"));
+    op->SetInput("MaxMap", this->Output("MaxMap"));
+    op->SetOutput(framework::GradVarName("X"), this->InputGrad("X"));
+    op->SetAttrMap(this->Attrs());
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OPERATOR(right_pool,
+                  ops::RightPoolOp,
+                  ops::RightPoolOpMaker,
+                  ops::RightPoolGradDescMaker<paddle::framework::OpDesc>,
+                  ops::RightPoolGradDescMaker<paddle::imperative::OpBase>);
+REGISTER_OPERATOR(right_pool_grad, ops::RightPoolOpGrad);

ppdet/ext_op/src/right_pool_op.cu

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+#include "paddle/fluid/platform/cuda_primitives.h"
+#include "paddle/fluid/memory/memory.h"
+#include <vector>
+#include "util.cu.h"
+
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+static constexpr int kNumCUDAThreads = 512;
+static constexpr int kNumMaximumNumBlocks = 4096;
+
+static inline int NumBlocks(const int N) {
+  return std::min((N + kNumCUDAThreads - 1) / kNumCUDAThreads,
+                  kNumMaximumNumBlocks);
+}
+
+template <typename T>
+class RightPoolOpCUDAKernel : public framework::OpKernel<T> {
+public:
+  void Compute(const framework::ExecutionContext &ctx) const override {
+    PADDLE_ENFORCE(platform::is_gpu_place(ctx.GetPlace()),
+                   "This kernel only runs on GPU device.");
+    auto *x = ctx.Input<Tensor>("X");
+    auto *max_map = ctx.Output<Tensor>("MaxMap");
+    auto *output = ctx.Output<Tensor>("Output");
+    auto *x_data = x->data<T>();
+    auto x_dims = x->dims();
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int num = x->numel();
+    auto& dev_ctx = ctx.cuda_device_context();
+
+    int *max_map_data = max_map->mutable_data<int>(x_dims, dev_ctx.GetPlace());
+    T *output_data = output->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int blocks = NumBlocks(num / width);
+  
+    auto max_val_ptr = memory::Alloc(gpu_place, num / width * sizeof(T));
+    T* max_val_data = reinterpret_cast<T*>(max_val_ptr->ptr());
+    auto max_ind_ptr = memory::Alloc(gpu_place, num / width * sizeof(int));
+    int* max_ind_data = reinterpret_cast<int*>(max_ind_ptr->ptr());
+
+    GetMaxInfo<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), NC_num, height, width, 3, false, max_val_data, max_ind_data, max_map_data);
+
+    blocks = NumBlocks(num);
+    ScatterAddFw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), max_map_data, NC_num, height, width, 3, output_data);
+
+  }
+};
+
+template <typename T>
+class RightPoolGradOpCUDAKernel : public framework::OpKernel<T> {
+ public:
+  void Compute(const framework::ExecutionContext& ctx) const override {
+    auto* x = ctx.Input<Tensor>("X");
+    auto* max_map = ctx.Input<Tensor>("MaxMap");
+    auto* out_grad = ctx.Input<Tensor>(framework::GradVarName("Output"));
+    auto* in_grad = ctx.Output<Tensor>(framework::GradVarName("X"));
+    auto x_dims = x->dims();
+    
+    auto& dev_ctx = ctx.cuda_device_context();
+    T* in_grad_data = in_grad->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int grad_num = in_grad->numel();
+    int blocks = NumBlocks(grad_num);
+    FillConstant<T><<<blocks, threads, 0, dev_ctx.stream()>>>(in_grad_data, 0, grad_num);
+
+    ScatterAddBw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(out_grad->data<T>(), max_map->data<int>(), NC_num, height, width, 3, in_grad_data);
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OP_CUDA_KERNEL(right_pool,
+                        ops::RightPoolOpCUDAKernel<float>,
+                        ops::RightPoolOpCUDAKernel<double>);
+REGISTER_OP_CUDA_KERNEL(right_pool_grad,
+                        ops::RightPoolGradOpCUDAKernel<float>,
+                        ops::RightPoolGradOpCUDAKernel<double>);

ppdet/ext_op/src/top_pool_op.cc

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+class TopPoolOp : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    ctx->ShareDim("X", /*->*/ "MaxMap");
+    ctx->ShareDim("X", /*->*/ "Output");
+  }
+
+protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(ctx.Input<Tensor>("X")->type(), 
+                                   ctx.GetPlace());
+  }
+};
+
+class TopPoolOpMaker : public framework::OpProtoAndCheckerMaker {
+public:
+  void Make() override {
+    AddInput("X",
+             "Input with shape (batch, C, H, W)");
+    AddOutput("MaxMap", "Max map with index of maximum value of input");
+    AddOutput("Output", "Output with same shape as input(X)");
+    AddComment(
+        R"Doc(
+This operatio calculates the top pooling output based on the input.
+Scan the input from bottom to top for the vertical max-pooling.
+The output has the same shape with input.
+        )Doc");
+  }
+};
+
+class TopPoolOpGrad : public framework::OperatorWithKernel {
+public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+protected:
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("X"), "Input(X) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput("MaxMap"), "Input(MaxMap) should not be null");
+    PADDLE_ENFORCE(ctx->HasInput(framework::GradVarName("Output")),
+                   "Input(Output@GRAD) should not be null");
+    
+    auto out_grad_name = framework::GradVarName("Output");
+    ctx->ShareDim(out_grad_name, framework::GradVarName("X"));
+  }
+
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        ctx.Input<Tensor>(framework::GradVarName("Output"))->type(),
+        ctx.GetPlace());
+  }
+};
+
+template <typename T>
+class TopPoolGradDescMaker : public framework::SingleGradOpMaker<T> {
+ public:
+  using framework::SingleGradOpMaker<T>::SingleGradOpMaker;
+
+ protected:
+  void Apply(GradOpPtr<T> op) const override {
+    op->SetType("top_pool_grad");
+    op->SetInput("X", this->Input("X"));
+    op->SetInput(framework::GradVarName("Output"), this->OutputGrad("Output"));
+    op->SetInput("MaxMap", this->Output("MaxMap"));
+    op->SetOutput(framework::GradVarName("X"), this->InputGrad("X"));
+    op->SetAttrMap(this->Attrs());
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OPERATOR(top_pool,
+                  ops::TopPoolOp,
+                  ops::TopPoolOpMaker,
+                  ops::TopPoolGradDescMaker<paddle::framework::OpDesc>,
+                  ops::TopPoolGradDescMaker<paddle::imperative::OpBase>);
+REGISTER_OPERATOR(top_pool_grad, ops::TopPoolOpGrad);

ppdet/ext_op/src/top_pool_op.cu

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+GUnless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+#include "paddle/fluid/platform/cuda_primitives.h"
+#include "paddle/fluid/memory/memory.h"
+#include <vector>
+#include "util.cu.h"
+
+namespace paddle {
+namespace operators {
+
+using Tensor = framework::Tensor;
+
+static constexpr int kNumCUDAThreads = 512;
+static constexpr int kNumMaximumNumBlocks = 4096;
+
+static inline int NumBlocks(const int N) {
+  return std::min((N + kNumCUDAThreads - 1) / kNumCUDAThreads,
+                  kNumMaximumNumBlocks);
+}
+
+template <typename T>
+class TopPoolOpCUDAKernel : public framework::OpKernel<T> {
+public:
+  void Compute(const framework::ExecutionContext &ctx) const override {
+    PADDLE_ENFORCE(platform::is_gpu_place(ctx.GetPlace()),
+                   "This kernel only runs on GPU device.");
+    auto *x = ctx.Input<Tensor>("X");
+    auto *max_map = ctx.Output<Tensor>("MaxMap");
+    auto *output = ctx.Output<Tensor>("Output");
+    auto *x_data = x->data<T>();
+    auto x_dims = x->dims();
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int num = x->numel();
+    auto& dev_ctx = ctx.cuda_device_context();
+
+    int *max_map_data = max_map->mutable_data<int>(x_dims, dev_ctx.GetPlace());
+    T *output_data = output->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int blocks = NumBlocks(num / height);
+  
+    auto max_val_ptr = memory::Alloc(gpu_place, num / height * sizeof(T));
+    T* max_val_data = reinterpret_cast<T*>(max_val_ptr->ptr());
+    auto max_ind_ptr = memory::Alloc(gpu_place, num / height * sizeof(int));
+    int* max_ind_data = reinterpret_cast<int*>(max_ind_ptr->ptr());
+
+    GetMaxInfo<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), NC_num, height, width, 2, true, max_val_data, max_ind_data, max_map_data);
+
+    blocks = NumBlocks(num);
+    ScatterAddFw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(x->data<T>(), max_map_data, NC_num, height, width, 2, output_data);
+  }
+};
+
+template <typename T>
+class TopPoolGradOpCUDAKernel : public framework::OpKernel<T> {
+ public:
+  void Compute(const framework::ExecutionContext& ctx) const override {
+    auto* x = ctx.Input<Tensor>("X");
+    auto* max_map = ctx.Input<Tensor>("MaxMap");
+    auto* out_grad = ctx.Input<Tensor>(framework::GradVarName("Output"));
+    auto* in_grad = ctx.Output<Tensor>(framework::GradVarName("X"));
+    auto x_dims = x->dims();
+    auto& dev_ctx = ctx.cuda_device_context();
+    T* in_grad_data = in_grad->mutable_data<T>(x_dims, dev_ctx.GetPlace());
+    auto gpu_place = boost::get<platform::CUDAPlace>(dev_ctx.GetPlace());
+    
+    int threads = kNumCUDAThreads;
+    int NC_num = x_dims[0] * x_dims[1];
+    int height = x_dims[2];
+    int width = x_dims[3];
+    int grad_num = in_grad->numel();
+    int blocks = NumBlocks(grad_num);
+    FillConstant<T><<<blocks, threads, 0, dev_ctx.stream()>>>(in_grad_data, 0, grad_num);
+
+    ScatterAddBw<T><<<blocks, threads, 0, dev_ctx.stream()>>>(out_grad->data<T>(), max_map->data<int>(), NC_num, height, width, 2, in_grad_data);
+  }
+};
+
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OP_CUDA_KERNEL(top_pool,
+                        ops::TopPoolOpCUDAKernel<float>,
+                        ops::TopPoolOpCUDAKernel<double>);
+REGISTER_OP_CUDA_KERNEL(top_pool_grad,
+                        ops::TopPoolGradOpCUDAKernel<float>,
+                        ops::TopPoolGradOpCUDAKernel<double>);

ppdet/ext_op/src/util.cu.h

+/* Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserve.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License. */
+
+#include "paddle/fluid/framework/op_registry.h"
+#include "paddle/fluid/platform/cuda_primitives.h"
+#include "paddle/fluid/memory/memory.h"
+#include <vector>
+
+namespace paddle {
+namespace operators {
+
+using framework::Tensor;
+
+#define CUDA_1D_KERNEL_LOOP(i, n)                              \
+  for (int i = blockIdx.x * blockDim.x + threadIdx.x; i < (n); \
+       i += blockDim.x * gridDim.x)
+
+template <typename T>
+__global__ void FillConstant(T* x, int num, int fill_num) {
+  CUDA_1D_KERNEL_LOOP(i, fill_num) {
+    x[i] = static_cast<T>(num);
+  }
+}
+
+template <typename T>
+__global__ void SliceOnAxis(const T* x, const int NC_num, const int H, const int W,
+                   const int axis, const int start, const int end, 
+                   T* output) {
+  int HW_num = H * W;
+  int length = axis == 2 ? W : H;
+  int sliced_len = end - start;
+  int cur_HW_num = length * sliced_len;
+  // slice input on H or W (axis is 2 or 3)
+  CUDA_1D_KERNEL_LOOP(i, NC_num * cur_HW_num) {
+    int NC_id = i / cur_HW_num;
+    int HW_id = i % cur_HW_num;
+    if (axis == 2){
+      output[i] = x[NC_id * HW_num + start * W + HW_id];
+    } else if (axis == 3) {
+      int col = HW_id % sliced_len;
+      int row = HW_id / sliced_len;
+      output[i] = x[NC_id * HW_num + row * W + start + col];
+    }
+  } 
+}
+
+template <typename T>
+__global__  void MaxOut(const T* input, const int next_ind, const int NC_num,
+                        const int H, const int W, const int axis, 
+                        const int start, const int end, T* output) {
+  int HW_num = H * W;
+  int length = axis == 2 ? W : H; 
+  T cur = static_cast<T>(0.);
+  T next = static_cast<T>(0.);
+  T max_v = static_cast<T>(0.);
+  int sliced_len = end - start;
+  int cur_HW_num = length * sliced_len;
+  // compare cur and next and assign max values to output
+  CUDA_1D_KERNEL_LOOP(i, NC_num * cur_HW_num) {
+    int NC_id = i / cur_HW_num;
+    int HW_id = i % cur_HW_num;
+   
+    if (axis == 2){
+      cur = input[NC_id * HW_num + start * W + HW_id];
+      next = input[NC_id * HW_num + next_ind * W + HW_id];
+      max_v = cur > next ? cur : next; 
+      output[NC_id * HW_num + start * W + HW_id] = max_v;
+    } else if (axis == 3) {
+      int col = HW_id % sliced_len;
+      int row = HW_id / sliced_len;
+      cur = input[NC_id * HW_num + row * W + start + col];
+      next = input[NC_id * HW_num + row * W + next_ind + col];
+      max_v = cur > next ? cur : next;
+      output[NC_id * HW_num + row * W + start + col] = max_v;
+    }
+    __syncthreads();
+  }
+}
+
+template <typename T>
+__global__  void UpdateMaxInfo(const T* input, const int NC_num, 
+                               const int H, const int W, const int axis, 
+                               const int index, T* max_val, int* max_ind) {
+  int length = axis == 2 ? W : H;
+  int HW_num = H * W; 
+  T val = static_cast<T>(0.);
+  CUDA_1D_KERNEL_LOOP(i, NC_num * length) {
+    int NC_id = i / length;
+    int length_id = i % length;
+    if (axis == 2) {
+      val = input[NC_id * HW_num + index * W + length_id];
+    } else if (axis == 3) {
+      val = input[NC_id * HW_num + length_id * W + index];
+    }
+    if (val > max_val[i]) {
+      max_val[i] = val;
+      max_ind[i] = index;
+    }
+    __syncthreads();
+  }
+}
+
+template <typename T>
+__global__  void ScatterAddOnAxis(const T* input, const int start, const int* max_ind, const int NC_num, const int H, const int W, const int axis, T* output) {
+  int length = axis == 2 ? W : H;
+  int HW_num = H * W;
+  CUDA_1D_KERNEL_LOOP(i, NC_num * length) { 
+    int NC_id = i / length;
+    int length_id = i % length;
+    int id_ = max_ind[i];
+    if (axis == 2) {
+      platform::CudaAtomicAdd(output + NC_id * HW_num + id_ * W + length_id, input[NC_id * HW_num + start * W + length_id]);
+      //output[NC_id * HW_num + id_ * W + length_id] += input[NC_id * HW_num + start * W + length_id];
+    } else if (axis == 3) {
+      platform::CudaAtomicAdd(output + NC_id * HW_num + length_id * W + id_, input[NC_id * HW_num + length_id * W + start]);
+      //output[NC_id * HW_num + length_id * W + id_] += input[NC_id * HW_num + length_id * W + start];
+    }
+    __syncthreads();
+  }
+}
+
+template <typename T>
+__global__ void GetMaxInfo(const T* input, const int NC_num,
+                           const int H, const int W, const int axis,
+                           const bool reverse, T* max_val, int* max_ind,
+                           int* max_map) {
+   int start = 0;
+   int end = axis == 2 ? H: W;
+   int s = reverse ? end-1 : start;
+   int e = reverse ? start-1 : end;
+   int step = reverse ? -1 : 1;
+   int len = axis == 2 ? W : H;
+   int loc = 0;
+   T val = static_cast<T>(0.);
+   for (int i = s; ; ) {
+     if (i == s) {
+       CUDA_1D_KERNEL_LOOP(j, NC_num * len) {
+         int NC_id = j / len;
+         int len_id = j % len;
+         if (axis == 2) {
+           loc = NC_id * H * W + i * W + len_id;
+         }  else if (axis == 3){
+           loc = NC_id * H * W + len_id * W + i;
+         }
+         max_ind[j] = i;
+         max_map[loc] = max_ind[j];
+         max_val[j] = input[loc];   
+         __syncthreads();
+       }
+     } else {
+       CUDA_1D_KERNEL_LOOP(j, NC_num * len) {
+         int NC_id = j / len;
+         int len_id = j % len;
+       
+         if (axis == 2) {
+           loc = NC_id * H * W + i * W + len_id;
+         } else if (axis == 3){
+           loc = NC_id * H * W + len_id * W + i;
+         }
+         val = input[loc];
+         T max_v = max_val[j];
+         if (val > max_v) {
+           max_val[j] = val;
+           max_map[loc] = i;
+           max_ind[j] = i;
+         } else {
+           max_map[loc] = max_ind[j];
+         }
+         __syncthreads();
+       }
+     }
+     i += step;
+     if (s < e && i >= e) break;
+     if (s > e && i <= e) break;
+   }
+}
+
+template <typename T>
+__global__ void ScatterAddFw(const T* input, const int* max_map, const int NC_num, const int H, const int W, const int axis, T* output){
+  CUDA_1D_KERNEL_LOOP(i, NC_num * H * W) {
+    int loc = max_map[i];
+    int NC_id = i / (H * W);
+    int len_id = 0;
+    if (axis == 2) {
+      len_id = i % W;
+      output[i] = input[NC_id * H * W + loc * W + len_id];
+    } else {
+      len_id = i % (H * W) / W;
+      output[i] = input[NC_id * H * W + len_id * W + loc];
+    }
+  }
+}
+
+template <typename T>
+__global__ void ScatterAddBw(const T* input, const int* max_map, const int NC_num, const int H, const int W, const int axis, T* output){
+  CUDA_1D_KERNEL_LOOP(i, NC_num * H * W) {
+    int loc = max_map[i];
+    int NC_id = i / (H * W);
+    int len_id = 0;
+    int offset = 0;
+    if (axis == 2) {
+      len_id = i % W;
+      offset = NC_id * H * W + loc * W + len_id;
+    } else {
+      len_id = i % (H * W) / W;
+      offset = NC_id * H * W + len_id * W + loc;
+    }
+    platform::CudaAtomicAdd(output + offset, input[i]);
+  }
+}
+
+}  // namespace operators
+}  // namespace paddle

ppdet/ext_op/test/test_corner_pool.py

+#   Copyright (c) 2019 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import print_function
+
+import unittest
+import numpy as np
+import paddle.fluid as fluid
+import cornerpool_lib
+
+
+def bottom_pool_np(x):
+    height = x.shape[2]
+    output = x.copy()
+    for ind in range(height):
+        cur = output[:, :, ind:height, :]
+        next = output[:, :, :height - ind, :]
+        output[:, :, ind:height, :] = np.maximum(cur, next)
+    return output
+
+
+def top_pool_np(x):
+    height = x.shape[2]
+    output = x.copy()
+    for ind in range(height):
+        cur = output[:, :, :height - ind, :]
+        next = output[:, :, ind:height, :]
+        output[:, :, :height - ind, :] = np.maximum(cur, next)
+    return output
+
+
+def right_pool_np(x):
+    width = x.shape[3]
+    output = x.copy()
+    for ind in range(width):
+        cur = output[:, :, :, ind:width]
+        next = output[:, :, :, :width - ind]
+        output[:, :, :, ind:width] = np.maximum(cur, next)
+    return output
+
+
+def left_pool_np(x):
+    width = x.shape[3]
+    output = x.copy()
+    for ind in range(width):
+        cur = output[:, :, :, :width - ind]
+        next = output[:, :, :, ind:width]
+        output[:, :, :, :width - ind] = np.maximum(cur, next)
+    return output
+
+
+class TestRightPoolOp(unittest.TestCase):
+    def funcmap(self):
+        self.func_map = {
+            'bottom_x': [cornerpool_lib.bottom_pool, bottom_pool_np],
+            'top_x': [cornerpool_lib.top_pool, top_pool_np],
+            'right_x': [cornerpool_lib.right_pool, right_pool_np],
+            'left_x': [cornerpool_lib.left_pool, left_pool_np]
+        }
+
+    def setup(self):
+        self.name = 'right_x'
+
+    def test_check_output(self):
+        self.funcmap()
+        self.setup()
+        x_shape = (2, 10, 16, 16)
+        x_type = "float64"
+
+        sp = fluid.Program()
+        tp = fluid.Program()
+        place = fluid.CUDAPlace(0)
+
+        with fluid.program_guard(tp, sp):
+            x = fluid.layers.data(
+                name=self.name,
+                shape=x_shape,
+                dtype=x_type,
+                append_batch_size=False)
+            y = self.func_map[self.name][0](x)
+
+            np.random.seed(0)
+            x_np = np.random.uniform(-1000, 1000, x_shape).astype(x_type)
+
+        out_np = self.func_map[self.name][1](x_np)
+
+        exe = fluid.Executor(place)
+        outs = exe.run(tp, feed={self.name: x_np}, fetch_list=[y])
+
+        self.assertTrue(np.allclose(outs, out_np))
+
+
+class TestTopPoolOp(TestRightPoolOp):
+    def setup(self):
+        self.name = 'top_x'
+
+
+class TestBottomPoolOp(TestRightPoolOp):
+    def setup(self):
+        self.name = 'bottom_x'
+
+
+class TestLeftPoolOp(TestRightPoolOp):
+    def setup(self):
+        self.name = 'left_x'
+
+
+if __name__ == "__main__":
+    unittest.main()

ppdet/modeling/anchor_heads/__init__.py

@@ -18,8 +18,10 @@ from . import rpn_head
 from . import yolo_head
 from . import retina_head
 from . import fcos_head
+from . import corner_head
 
 from .rpn_head import *
 from .yolo_head import *
 from .retina_head import *
 from .fcos_head import *
+from .corner_head import *

ppdet/modeling/anchor_heads/corner_head.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from paddle import fluid
+from paddle.fluid.param_attr import ParamAttr
+from paddle.fluid.initializer import Constant
+
+from ..backbones.hourglass import _conv_norm, kaiming_init
+from ppdet.core.workspace import register
+import numpy as np
+try:
+    import cornerpool_lib
+except:
+    print(
+        "warning: cornerpool_lib not found, compile in ext_op at first if needed"
+    )
+
+__all__ = ['CornerHead']
+
+
+def corner_output(x, pool1, pool2, dim, name=None):
+    p_conv1 = fluid.layers.conv2d(
+        pool1 + pool2,
+        filter_size=3,
+        num_filters=dim,
+        padding=1,
+        param_attr=ParamAttr(
+            name=name + "_p_conv1_weight",
+            initializer=kaiming_init(pool1 + pool2, 3)),
+        bias_attr=False,
+        name=name + '_p_conv1')
+    p_bn1 = fluid.layers.batch_norm(
+        p_conv1,
+        param_attr=ParamAttr(name=name + '_p_bn1_weight'),
+        bias_attr=ParamAttr(name=name + '_p_bn1_bias'),
+        moving_mean_name=name + '_p_bn1_running_mean',
+        moving_variance_name=name + '_p_bn1_running_var',
+        name=name + '_p_bn1')
+
+    conv1 = fluid.layers.conv2d(
+        x,
+        filter_size=1,
+        num_filters=dim,
+        param_attr=ParamAttr(
+            name=name + "_conv1_weight", initializer=kaiming_init(x, 1)),
+        bias_attr=False,
+        name=name + '_conv1')
+    bn1 = fluid.layers.batch_norm(
+        conv1,
+        param_attr=ParamAttr(name=name + '_bn1_weight'),
+        bias_attr=ParamAttr(name=name + '_bn1_bias'),
+        moving_mean_name=name + '_bn1_running_mean',
+        moving_variance_name=name + '_bn1_running_var',
+        name=name + '_bn1')
+
+    relu1 = fluid.layers.relu(p_bn1 + bn1)
+    conv2 = _conv_norm(
+        relu1, 3, dim, pad=1, bn_act='relu', name=name + '_conv2')
+    return conv2
+
+
+def corner_pool(x, dim, pool1, pool2, is_test=False, name=None):
+    p1_conv1 = _conv_norm(
+        x, 3, 128, pad=1, bn_act='relu', name=name + '_p1_conv1')
+    pool1 = pool1(p1_conv1, is_test=is_test, name=name + '_pool1')
+    p2_conv1 = _conv_norm(
+        x, 3, 128, pad=1, bn_act='relu', name=name + '_p2_conv1')
+    pool2 = pool2(p2_conv1, is_test=is_test, name=name + '_pool2')
+
+    conv2 = corner_output(x, pool1, pool2, dim, name)
+    return conv2
+
+
+def gather_feat(feat, ind, batch_size=1):
+    feats = []
+    for bind in range(batch_size):
+        feat_b = feat[bind]
+        ind_b = ind[bind]
+        ind_b.stop_gradient = True
+        feat_bg = fluid.layers.gather(feat_b, ind_b)
+        feats.append(fluid.layers.unsqueeze(feat_bg, axes=[0]))
+    feat_g = fluid.layers.concat(feats, axis=0)
+    return feat_g
+
+
+def mask_feat(feat, ind, batch_size=1):
+    feat_t = fluid.layers.transpose(feat, [0, 2, 3, 1])
+    C = feat_t.shape[3]
+    feat_r = fluid.layers.reshape(feat_t, [0, -1, C])
+    return gather_feat(feat_r, ind, batch_size)
+
+
+def nms(heat):
+    hmax = fluid.layers.pool2d(heat, pool_size=3, pool_padding=1)
+    keep = fluid.layers.cast(heat == hmax, 'float32')
+    return heat * keep
+
+
+def _topk(scores, batch_size, height, width, K):
+    scores_r = fluid.layers.reshape(scores, [batch_size, -1])
+    topk_scores, topk_inds = fluid.layers.topk(scores_r, K)
+    topk_clses = topk_inds / (height * width)
+    topk_inds = topk_inds % (height * width)
+    topk_ys = fluid.layers.cast(topk_inds / width, 'float32')
+    topk_xs = fluid.layers.cast(topk_inds % width, 'float32')
+    return topk_scores, topk_inds, topk_clses, topk_ys, topk_xs
+
+
+def filter_scores(scores, index_list):
+    for ind in index_list:
+        tmp = scores * fluid.layers.cast((1 - ind), 'float32')
+        scores = tmp - fluid.layers.cast(ind, 'float32')
+    return scores
+
+
+def decode(tl_heat,
+           br_heat,
+           tl_tag,
+           br_tag,
+           tl_regr,
+           br_regr,
+           ae_threshold=1,
+           num_dets=1000,
+           K=100,
+           batch_size=1):
+    shape = fluid.layers.shape(tl_heat)
+    H, W = shape[2], shape[3]
+
+    tl_heat = fluid.layers.sigmoid(tl_heat)
+    br_heat = fluid.layers.sigmoid(br_heat)
+
+    tl_heat_nms = nms(tl_heat)
+    br_heat_nms = nms(br_heat)
+
+    tl_scores, tl_inds, tl_clses, tl_ys, tl_xs = _topk(tl_heat_nms, batch_size,
+                                                       H, W, K)
+    br_scores, br_inds, br_clses, br_ys, br_xs = _topk(br_heat_nms, batch_size,
+                                                       H, W, K)
+    tl_ys = fluid.layers.expand(
+        fluid.layers.reshape(tl_ys, [-1, K, 1]), [1, 1, K])
+    tl_xs = fluid.layers.expand(
+        fluid.layers.reshape(tl_xs, [-1, K, 1]), [1, 1, K])
+    br_ys = fluid.layers.expand(
+        fluid.layers.reshape(br_ys, [-1, 1, K]), [1, K, 1])
+    br_xs = fluid.layers.expand(
+        fluid.layers.reshape(br_xs, [-1, 1, K]), [1, K, 1])
+
+    tl_regr = mask_feat(tl_regr, tl_inds, batch_size)
+    br_regr = mask_feat(br_regr, br_inds, batch_size)
+    tl_regr = fluid.layers.reshape(tl_regr, [-1, K, 1, 2])
+    br_regr = fluid.layers.reshape(br_regr, [-1, 1, K, 2])
+
+    tl_xs = tl_xs + tl_regr[:, :, :, 0]
+    tl_ys = tl_ys + tl_regr[:, :, :, 1]
+    br_xs = br_xs + br_regr[:, :, :, 0]
+    br_ys = br_ys + br_regr[:, :, :, 1]
+
+    bboxes = fluid.layers.stack([tl_xs, tl_ys, br_xs, br_ys], axis=-1)
+
+    tl_tag = mask_feat(tl_tag, tl_inds, batch_size)
+    br_tag = mask_feat(br_tag, br_inds, batch_size)
+    tl_tag = fluid.layers.expand(
+        fluid.layers.reshape(tl_tag, [-1, K, 1]), [1, 1, K])
+    br_tag = fluid.layers.expand(
+        fluid.layers.reshape(br_tag, [-1, 1, K]), [1, K, 1])
+    dists = fluid.layers.abs(tl_tag - br_tag)
+
+    tl_scores = fluid.layers.expand(
+        fluid.layers.reshape(tl_scores, [-1, K, 1]), [1, 1, K])
+    br_scores = fluid.layers.expand(
+        fluid.layers.reshape(br_scores, [-1, 1, K]), [1, K, 1])
+    scores = (tl_scores + br_scores) / 2.
+
+    tl_clses = fluid.layers.expand(
+        fluid.layers.reshape(tl_clses, [-1, K, 1]), [1, 1, K])
+    br_clses = fluid.layers.expand(
+        fluid.layers.reshape(br_clses, [-1, 1, K]), [1, K, 1])
+    cls_inds = fluid.layers.cast(tl_clses != br_clses, 'int32')
+    dist_inds = fluid.layers.cast(dists > ae_threshold, 'int32')
+
+    width_inds = fluid.layers.cast(br_xs < tl_xs, 'int32')
+    height_inds = fluid.layers.cast(br_ys < tl_ys, 'int32')
+
+    scores = filter_scores(scores,
+                           [cls_inds, dist_inds, width_inds, height_inds])
+    scores = fluid.layers.reshape(scores, [-1, K * K])
+
+    scores, inds = fluid.layers.topk(scores, num_dets)
+    scores = fluid.layers.reshape(scores, [-1, num_dets, 1])
+
+    bboxes = fluid.layers.reshape(bboxes, [batch_size, -1, 4])
+    bboxes = gather_feat(bboxes, inds, batch_size)
+
+    clses = fluid.layers.reshape(tl_clses, [batch_size, -1, 1])
+    clses = gather_feat(clses, inds, batch_size)
+
+    tl_scores = fluid.layers.reshape(tl_scores, [batch_size, -1, 1])
+    tl_scores = gather_feat(tl_scores, inds, batch_size)
+    br_scores = fluid.layers.reshape(br_scores, [batch_size, -1, 1])
+    br_scores = gather_feat(br_scores, inds, batch_size)
+
+    bboxes = fluid.layers.cast(bboxes, 'float32')
+    clses = fluid.layers.cast(clses, 'float32')
+    return bboxes, scores, tl_scores, br_scores, clses
+
+
+@register
+class CornerHead(object):
+    """
+    CornerNet head with corner_pooling
+
+    Args:
+        train_batch_size(int): batch_size in training process
+        test_batch_size(int): batch_size in test process, 1 by default
+        num_classes(int): num of classes, 80 by default
+        stack(int): stack of backbone, 2 by default
+        pull_weight(float): weight of pull_loss, 0.1 by default
+        push_weight(float): weight of push_loss, 0.1 by default
+        ae_threshold(float|int): threshold for valid distance of predicted tags, 1 by default
+        num_dets(int): num of detections, 1000 by default
+        top_k(int): choose top_k pair of corners in prediction, 100 by default 
+    """
+    __shared__ = ['num_classes', 'stack']
+
+    def __init__(self,
+                 train_batch_size,
+                 test_batch_size=1,
+                 num_classes=80,
+                 stack=2,
+                 pull_weight=0.1,
+                 push_weight=0.1,
+                 ae_threshold=1,
+                 num_dets=1000,
+                 top_k=100):
+        self.train_batch_size = train_batch_size
+        self.test_batch_size = test_batch_size
+        self.num_classes = num_classes
+        self.stack = stack
+        self.pull_weight = pull_weight
+        self.push_weight = push_weight
+        self.ae_threshold = ae_threshold
+        self.num_dets = num_dets
+        self.K = top_k
+        self.tl_heats = []
+        self.br_heats = []
+        self.tl_tags = []
+        self.br_tags = []
+        self.tl_offs = []
+        self.br_offs = []
+
+    def pred_mod(self, x, dim, name=None):
+        conv0 = _conv_norm(
+            x, 1, 256, with_bn=False, bn_act='relu', name=name + '_0')
+        conv1 = fluid.layers.conv2d(
+            input=conv0,
+            filter_size=1,
+            num_filters=dim,
+            param_attr=ParamAttr(
+                name=name + "_1_weight", initializer=kaiming_init(conv0, 1)),
+            bias_attr=ParamAttr(
+                name=name + "_1_bias", initializer=Constant(-2.19)),
+            name=name + '_1')
+        return conv1
+
+    def get_output(self, input):
+        for ind in range(self.stack):
+            cnv = input[ind]
+            tl_modules = corner_pool(
+                cnv,
+                256,
+                cornerpool_lib.top_pool,
+                cornerpool_lib.left_pool,
+                name='tl_modules_' + str(ind))
+            br_modules = corner_pool(
+                cnv,
+                256,
+                cornerpool_lib.bottom_pool,
+                cornerpool_lib.right_pool,
+                name='br_modules_' + str(ind))
+
+            tl_heat = self.pred_mod(
+                tl_modules, self.num_classes, name='tl_heats_' + str(ind))
+            br_heat = self.pred_mod(
+                br_modules, self.num_classes, name='br_heats_' + str(ind))
+
+            tl_tag = self.pred_mod(tl_modules, 1, name='tl_tags_' + str(ind))
+            br_tag = self.pred_mod(br_modules, 1, name='br_tags_' + str(ind))
+
+            tl_off = self.pred_mod(tl_modules, 2, name='tl_offs_' + str(ind))
+            br_off = self.pred_mod(br_modules, 2, name='br_offs_' + str(ind))
+
+            self.tl_heats.append(tl_heat)
+            self.br_heats.append(br_heat)
+            self.tl_tags.append(tl_tag)
+            self.br_tags.append(br_tag)
+            self.tl_offs.append(tl_off)
+            self.br_offs.append(br_off)
+
+    def focal_loss(self, preds, gt, gt_masks):
+        preds_clip = []
+        none_pos = fluid.layers.cast(
+            fluid.layers.reduce_sum(gt_masks) == 0, 'float32')
+        none_pos.stop_gradient = True
+        min = fluid.layers.assign(np.array([1e-4], dtype='float32'))
+        max = fluid.layers.assign(np.array([1 - 1e-4], dtype='float32'))
+        for pred in preds:
+            pred_s = fluid.layers.sigmoid(pred)
+            pred_min = fluid.layers.elementwise_max(pred_s, min)
+            pred_max = fluid.layers.elementwise_min(pred_min, max)
+            preds_clip.append(pred_max)
+
+        ones = fluid.layers.ones_like(gt)
+
+        fg_map = fluid.layers.cast(gt == ones, 'float32')
+        fg_map.stop_gradient = True
+        num_pos = fluid.layers.reduce_sum(fg_map)
+        min_num = fluid.layers.ones_like(num_pos)
+        num_pos = fluid.layers.elementwise_max(num_pos, min_num)
+        num_pos.stop_gradient = True
+        bg_map = fluid.layers.cast(gt < ones, 'float32')
+        bg_map.stop_gradient = True
+        neg_weights = fluid.layers.pow(1 - gt, 4) * bg_map
+        neg_weights.stop_gradient = True
+        loss = fluid.layers.assign(np.array([0], dtype='float32'))
+        for ind, pred in enumerate(preds_clip):
+            pos_loss = fluid.layers.log(pred) * fluid.layers.pow(1 - pred,
+                                                                 2) * fg_map
+
+            neg_loss = fluid.layers.log(1 - pred) * fluid.layers.pow(
+                pred, 2) * neg_weights
+
+            pos_loss = fluid.layers.reduce_sum(pos_loss)
+            neg_loss = fluid.layers.reduce_sum(neg_loss)
+            focal_loss_ = (neg_loss + pos_loss) / (num_pos + none_pos)
+            loss -= focal_loss_
+        return loss
+
+    def ae_loss(self, tl_tag, br_tag, gt_masks):
+        num = fluid.layers.reduce_sum(gt_masks, dim=1)
+        num_stop_gradient = True
+        tag0 = fluid.layers.squeeze(tl_tag, [2])
+        tag1 = fluid.layers.squeeze(br_tag, [2])
+        tag_mean = (tag0 + tag1) / 2
+
+        tag0 = fluid.layers.pow(tag0 - tag_mean, 2) / (num + 1e-4) * gt_masks
+        tag1 = fluid.layers.pow(tag1 - tag_mean, 2) / (num + 1e-4) * gt_masks
+        tag0 = fluid.layers.reduce_sum(tag0)
+        tag1 = fluid.layers.reduce_sum(tag1)
+
+        pull = tag0 + tag1
+
+        mask_1 = fluid.layers.expand(
+            fluid.layers.unsqueeze(gt_masks, [1]), [1, gt_masks.shape[1], 1])
+        mask_2 = fluid.layers.expand(
+            fluid.layers.unsqueeze(gt_masks, [2]), [1, 1, gt_masks.shape[1]])
+        mask = fluid.layers.cast((mask_1 + mask_2) == 2, 'float32')
+        mask.stop_gradient = True
+
+        num2 = (num - 1) * num
+        num2.stop_gradient = True
+        tag_mean_1 = fluid.layers.expand(
+            fluid.layers.unsqueeze(tag_mean, [1]), [1, tag_mean.shape[1], 1])
+        tag_mean_2 = fluid.layers.expand(
+            fluid.layers.unsqueeze(tag_mean, [2]), [1, 1, tag_mean.shape[1]])
+        dist = tag_mean_1 - tag_mean_2
+        dist = 1 - fluid.layers.abs(dist)
+        dist = fluid.layers.relu(dist)
+        dist = dist - 1 / (num + 1e-4)
+        dist = dist / (num2 + 1e-4)
+        dist = dist * mask
+        push = fluid.layers.reduce_sum(dist)
+        return pull, push
+
+    def off_loss(self, off, gt_off, gt_masks):
+        mask = fluid.layers.unsqueeze(gt_masks, [2])
+        mask = fluid.layers.expand_as(mask, gt_off)
+        mask.stop_gradient = True
+        off_loss = fluid.layers.smooth_l1(off, gt_off, mask, mask)
+        off_loss = fluid.layers.reduce_sum(off_loss)
+        total_num = fluid.layers.reduce_sum(gt_masks)
+        total_num.stop_gradient = True
+        return off_loss / (total_num + 1e-4)
+
+    def get_loss(self, targets):
+        gt_tl_heat = targets['tl_heatmaps']
+        gt_br_heat = targets['br_heatmaps']
+        gt_masks = targets['tag_masks']
+        gt_tl_off = targets['tl_regrs']
+        gt_br_off = targets['br_regrs']
+        gt_tl_ind = targets['tl_tags']
+        gt_br_ind = targets['br_tags']
+        gt_masks = fluid.layers.cast(gt_masks, 'float32')
+
+        focal_loss = 0
+        focal_loss_ = self.focal_loss(self.tl_heats, gt_tl_heat, gt_masks)
+        focal_loss += focal_loss_
+        focal_loss_ = self.focal_loss(self.br_heats, gt_br_heat, gt_masks)
+        focal_loss += focal_loss_
+
+        pull_loss = 0
+        push_loss = 0
+
+        ones = fluid.layers.assign(np.array([1], dtype='float32'))
+        tl_tags = [
+            mask_feat(tl_tag, gt_tl_ind, self.train_batch_size)
+            for tl_tag in self.tl_tags
+        ]
+        br_tags = [
+            mask_feat(br_tag, gt_br_ind, self.train_batch_size)
+            for br_tag in self.br_tags
+        ]
+
+        pull_loss, push_loss = 0, 0
+
+        for tl_tag, br_tag in zip(tl_tags, br_tags):
+            pull, push = self.ae_loss(tl_tag, br_tag, gt_masks)
+            pull_loss += pull
+            push_loss += push
+
+        tl_offs = [
+            mask_feat(tl_off, gt_tl_ind, self.train_batch_size)
+            for tl_off in self.tl_offs
+        ]
+        br_offs = [
+            mask_feat(br_off, gt_br_ind, self.train_batch_size)
+            for br_off in self.br_offs
+        ]
+
+        off_loss = 0
+        for tl_off, br_off in zip(tl_offs, br_offs):
+            off_loss += self.off_loss(tl_off, gt_tl_off, gt_masks)
+            off_loss += self.off_loss(br_off, gt_br_off, gt_masks)
+
+        pull_loss = self.pull_weight * pull_loss
+        push_loss = self.push_weight * push_loss
+
+        loss = (
+            focal_loss + pull_loss + push_loss + off_loss) / len(self.tl_heats)
+        return {'loss': loss}
+
+    def get_prediction(self, input):
+        ind = self.stack - 1
+        tl_modules = corner_pool(
+            input,
+            256,
+            cornerpool_lib.top_pool,
+            cornerpool_lib.left_pool,
+            is_test=True,
+            name='tl_modules_' + str(ind))
+        br_modules = corner_pool(
+            input,
+            256,
+            cornerpool_lib.bottom_pool,
+            cornerpool_lib.right_pool,
+            is_test=True,
+            name='br_modules_' + str(ind))
+
+        tl_heat = self.pred_mod(
+            tl_modules, self.num_classes, name='tl_heats_' + str(ind))
+        br_heat = self.pred_mod(
+            br_modules, self.num_classes, name='br_heats_' + str(ind))
+
+        tl_tag = self.pred_mod(tl_modules, 1, name='tl_tags_' + str(ind))
+        br_tag = self.pred_mod(br_modules, 1, name='br_tags_' + str(ind))
+
+        tl_off = self.pred_mod(tl_modules, 2, name='tl_offs_' + str(ind))
+        br_off = self.pred_mod(br_modules, 2, name='br_offs_' + str(ind))
+
+        return decode(tl_heat, br_heat, tl_tag, br_tag, tl_off, br_off,
+                      self.ae_threshold, self.num_dets, self.K,
+                      self.test_batch_size)

ppdet/modeling/architectures/__init__.py

@@ -25,6 +25,7 @@ from . import retinanet
 from . import blazeface
 from . import faceboxes
 from . import fcos
+from . import cornernet_squeeze
 
 from .faster_rcnn import *
 from .mask_rcnn import *
@@ -37,3 +38,4 @@ from .retinanet import *
 from .blazeface import *
 from .faceboxes import *
 from .fcos import *
+from .cornernet_squeeze import *

ppdet/modeling/architectures/cascade_mask_rcnn.py

@@ -408,7 +408,7 @@ class CascadeMaskRCNN(object):
                 box_fields = ['bbox', 'bbox_flip'] if use_flip else ['bbox']
                 for key in box_fields:
                     inputs_def[key] = {
-                        'shape': [6],
+                        'shape': [None, 6],
                         'dtype': 'float32',
                         'lod_level': 1
                     }

ppdet/modeling/architectures/cornernet_squeeze.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from collections import OrderedDict
+
+from paddle import fluid
+
+from ppdet.core.workspace import register
+import numpy as np
+
+__all__ = ['CornerNetSqueeze']
+
+
+def rescale_bboxes(bboxes, ratios, borders):
+    x1, y1, x2, y2 = fluid.layers.split(bboxes, 4)
+    x1 = x1 / ratios[:, 1] - borders[:, 2]
+    x2 = x2 / ratios[:, 1] - borders[:, 2]
+    y1 = y1 / ratios[:, 0] - borders[:, 0]
+    y2 = y2 / ratios[:, 0] - borders[:, 0]
+    return fluid.layers.concat([x1, y1, x2, y2], axis=2)
+
+
+@register
+class CornerNetSqueeze(object):
+    """
+    """
+    __category__ = 'architecture'
+    __inject__ = ['backbone', 'corner_head', 'fpn']
+    __shared__ = ['num_classes']
+
+    def __init__(self,
+                 backbone,
+                 corner_head='CornerHead',
+                 num_classes=80,
+                 fpn=None):
+        super(CornerNetSqueeze, self).__init__()
+        self.backbone = backbone
+        self.corner_head = corner_head
+        self.num_classes = num_classes
+        self.fpn = fpn
+
+    def build(self, feed_vars, mode='train'):
+        im = feed_vars['image']
+        body_feats = self.backbone(im)
+        if self.fpn is not None:
+            body_feats, _ = self.fpn.get_output(body_feats)
+            body_feats = [body_feats.values()[-1]]
+        if mode == 'train':
+            target_vars = [
+                'tl_heatmaps', 'br_heatmaps', 'tag_masks', 'tl_regrs',
+                'br_regrs', 'tl_tags', 'br_tags'
+            ]
+            target = {key: feed_vars[key] for key in target_vars}
+            self.corner_head.get_output(body_feats)
+            loss = self.corner_head.get_loss(target)
+            return loss
+
+        elif mode == 'test':
+            ratios = feed_vars['ratios']
+            borders = feed_vars['borders']
+            bboxes, scores, tl_scores, br_scores, clses = self.corner_head.get_prediction(
+                body_feats[-1])
+            bboxes = rescale_bboxes(bboxes, ratios, borders)
+            detections = fluid.layers.concat([clses, scores, bboxes], axis=2)
+
+            detections = detections[0]
+            return {'bbox': detections}
+
+    def _inputs_def(self, image_shape, output_size, max_tag_len):
+        im_shape = [None] + image_shape
+        C = self.num_classes
+        # yapf: disable
+        inputs_def = {
+            'image':        {'shape': im_shape,  'dtype': 'float32', 'lod_level': 0},
+            'im_id':        {'shape': [None, 1], 'dtype': 'int64',   'lod_level': 0},
+            'gt_bbox':       {'shape': [None, 4], 'dtype': 'float32', 'lod_level': 1},
+            'gt_class':     {'shape': [None, 1], 'dtype': 'int32',   'lod_level': 1},
+            'ratios':       {'shape': [None, 2],  'dtype': 'float32', 'lod_level': 0},
+            'borders':      {'shape': [None, 4],  'dtype': 'float32', 'lod_level': 0},
+            'tl_heatmaps':  {'shape': [None, C, output_size, output_size],  'dtype': 'float32', 'lod_level': 0},
+            'br_heatmaps':  {'shape': [None, C, output_size, output_size],  'dtype': 'float32', 'lod_level': 0},
+            'tl_regrs':     {'shape': [None, max_tag_len, 2], 'dtype': 'float32', 'lod_level': 0},
+            'br_regrs':     {'shape': [None, max_tag_len, 2], 'dtype': 'float32', 'lod_level': 0},
+            'tl_tags':      {'shape': [None, max_tag_len], 'dtype': 'int64', 'lod_level': 0},
+            'br_tags':      {'shape': [None, max_tag_len], 'dtype': 'int64', 'lod_level': 0},
+            'tag_masks':     {'shape': [None, max_tag_len], 'dtype': 'int32', 'lod_level': 0},
+        }
+        # yapf: enable
+        return inputs_def
+
+    def build_inputs(
+            self,
+            image_shape=[3, None, None],
+            fields=[
+                'image', 'im_id', 'gt_box', 'gt_class', 'tl_heatmaps',
+                'br_heatmaps', 'tl_regrs', 'br_regrs', 'tl_tags', 'br_tags',
+                'tag_masks'
+            ],  # for train
+            output_size=64,
+            max_tag_len=128,
+            use_dataloader=True,
+            iterable=False):
+        inputs_def = self._inputs_def(image_shape, output_size, max_tag_len)
+        feed_vars = OrderedDict([(key, fluid.data(
+            name=key,
+            shape=inputs_def[key]['shape'],
+            dtype=inputs_def[key]['dtype'],
+            lod_level=inputs_def[key]['lod_level'])) for key in fields])
+        loader = fluid.io.DataLoader.from_generator(
+            feed_list=list(feed_vars.values()),
+            capacity=64,
+            use_double_buffer=True,
+            iterable=iterable) if use_dataloader else None
+        return feed_vars, loader
+
+    def train(self, feed_vars):
+        return self.build(feed_vars, mode='train')
+
+    def eval(self, feed_vars):
+        return self.build(feed_vars, mode='test')
+
+    def test(self, feed_vars):
+        return self.build(feed_vars, mode='test')

ppdet/modeling/architectures/mask_rcnn.py

@@ -311,7 +311,7 @@ class MaskRCNN(object):
                 box_fields = ['bbox', 'bbox_flip'] if use_flip else ['bbox']
                 for key in box_fields:
                     inputs_def[key] = {
-                        'shape': [6],
+                        'shape': [None, 6],
                         'dtype': 'float32',
                         'lod_level': 1
                     }

ppdet/modeling/backbones/__init__.py

@@ -29,6 +29,7 @@ from . import res2net
 from . import hrnet
 from . import hrfpn
 from . import bfp
+from . import hourglass
 
 from .resnet import *
 from .resnext import *
@@ -45,3 +46,4 @@ from .res2net import *
 from .hrnet import *
 from .hrfpn import *
 from .bfp import *
+from .hourglass import *

ppdet/modeling/backbones/hourglass.py

+# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from paddle import fluid
+from paddle.fluid.param_attr import ParamAttr
+from paddle.fluid.initializer import Uniform
+
+import functools
+from ppdet.core.workspace import register
+from .resnet import ResNet
+import math
+
+__all__ = ['Hourglass']
+
+
+def kaiming_init(input, filter_size):
+    fan_in = input.shape[1]
+    std = (1.0 / (fan_in * filter_size * filter_size))**0.5
+    return Uniform(0. - std, std)
+
+
+def _conv_norm(x,
+               k,
+               out_dim,
+               stride=1,
+               pad=0,
+               groups=None,
+               with_bn=True,
+               bn_act=None,
+               ind=None,
+               name=None):
+    conv_name = "_conv" if ind is None else "_conv" + str(ind)
+    bn_name = "_bn" if ind is None else "_bn" + str(ind)
+
+    conv = fluid.layers.conv2d(
+        input=x,
+        filter_size=k,
+        num_filters=out_dim,
+        stride=stride,
+        padding=pad,
+        groups=groups,
+        param_attr=ParamAttr(
+            name=name + conv_name + "_weight", initializer=kaiming_init(x, k)),
+        bias_attr=ParamAttr(
+            name=name + conv_name + "_bias", initializer=kaiming_init(x, k))
+        if not with_bn else False,
+        name=name + '_output')
+    if with_bn:
+        pattr = ParamAttr(name=name + bn_name + '_weight')
+        battr = ParamAttr(name=name + bn_name + '_bias')
+        out = fluid.layers.batch_norm(
+            input=conv,
+            act=bn_act,
+            name=name + '_bn_output',
+            param_attr=pattr,
+            bias_attr=battr,
+            moving_mean_name=name + bn_name + '_running_mean',
+            moving_variance_name=name + bn_name +
+            '_running_var') if with_bn else conv
+    else:
+        out = fluid.layers.relu(conv)
+    return out
+
+
+def residual_block(x, out_dim, k=3, stride=1, name=None):
+    p = (k - 1) // 2
+    conv1 = _conv_norm(
+        x, k, out_dim, pad=p, stride=stride, bn_act='relu', ind=1, name=name)
+    conv2 = _conv_norm(conv1, k, out_dim, pad=p, ind=2, name=name)
+
+    skip = _conv_norm(
+        x, 1, out_dim, stride=stride,
+        name=name + '_skip') if stride != 1 or x.shape[1] != out_dim else x
+    return fluid.layers.elementwise_add(
+        x=skip, y=conv2, act='relu', name=name + "_add")
+
+
+def fire_block(x, out_dim, sr=2, stride=1, name=None):
+    conv1 = _conv_norm(x, 1, out_dim // sr, ind=1, name=name)
+    conv_1x1 = fluid.layers.conv2d(
+        conv1,
+        filter_size=1,
+        num_filters=out_dim // 2,
+        stride=stride,
+        param_attr=ParamAttr(
+            name=name + "_conv_1x1_weight", initializer=kaiming_init(conv1, 1)),
+        bias_attr=False,
+        name=name + '_conv_1x1')
+    conv_3x3 = fluid.layers.conv2d(
+        conv1,
+        filter_size=3,
+        num_filters=out_dim // 2,
+        stride=stride,
+        padding=1,
+        groups=out_dim // sr,
+        param_attr=ParamAttr(
+            name=name + "_conv_3x3_weight", initializer=kaiming_init(conv1, 3)),
+        bias_attr=False,
+        name=name + '_conv_3x3',
+        use_cudnn=False)
+    conv2 = fluid.layers.concat(
+        [conv_1x1, conv_3x3], axis=1, name=name + '_conv2')
+    pattr = ParamAttr(name=name + '_bn2_weight')
+    battr = ParamAttr(name=name + '_bn2_bias')
+
+    bn2 = fluid.layers.batch_norm(
+        input=conv2,
+        name=name + '_bn2',
+        param_attr=pattr,
+        bias_attr=battr,
+        moving_mean_name=name + '_bn2_running_mean',
+        moving_variance_name=name + '_bn2_running_var')
+
+    if stride == 1 and x.shape[1] == out_dim:
+        return fluid.layers.elementwise_add(
+            x=bn2, y=x, act='relu', name=name + "_add_relu")
+    else:
+        return fluid.layers.relu(bn2, name="_relu")
+
+
+def make_layer(x, in_dim, out_dim, modules, block, name=None):
+    layers = block(x, out_dim, name=name + '_0')
+    for i in range(1, modules):
+        layers = block(layers, out_dim, name=name + '_' + str(i))
+    return layers
+
+
+def make_hg_layer(x, in_dim, out_dim, modules, block, name=None):
+    layers = block(x, out_dim, stride=2, name=name + '_0')
+    for i in range(1, modules):
+        layers = block(layers, out_dim, name=name + '_' + str(i))
+    return layers
+
+
+def make_layer_revr(x, in_dim, out_dim, modules, block, name=None):
+    for i in range(modules - 1):
+        x = block(x, in_dim, name=name + '_' + str(i))
+    layers = block(x, out_dim, name=name + '_' + str(modules - 1))
+    return layers
+
+
+def make_unpool_layer(x, dim, name=None):
+    pattr = ParamAttr(name=name + '_weight', initializer=kaiming_init(x, 4))
+    battr = ParamAttr(name=name + '_bias', initializer=kaiming_init(x, 4))
+    layer = fluid.layers.conv2d_transpose(
+        input=x,
+        num_filters=dim,
+        filter_size=4,
+        stride=2,
+        padding=1,
+        param_attr=pattr,
+        bias_attr=battr)
+    return layer
+
+
+@register
+class Hourglass(object):
+    """
+    Hourglass Network, see https://arxiv.org/abs/1603.06937
+    Args:
+        stack (int): stack of hourglass, 2 by default
+        dims (list): dims of each level in hg_module
+        modules (list): num of modules in each level
+    """
+    __shared__ = ['stack']
+
+    def __init__(self,
+                 stack=2,
+                 dims=[256, 256, 384, 384, 512],
+                 modules=[2, 2, 2, 2, 4],
+                 block_name='fire'):
+        super(Hourglass, self).__init__()
+        self.stack = stack
+        assert len(dims) == len(modules), \
+            "Expected len of dims equal to len of modules, Receiced len of "\
+            "dims: {}, len of modules: {}".format(len(dims), len(modules))
+        self.dims = dims
+        self.modules = modules
+        self.num_level = len(dims) - 1
+        block_dict = {'fire': fire_block}
+        self.block = block_dict[block_name]
+
+    def __call__(self, input, name='hg'):
+        inter = self.pre(input, name + '_pre')
+        cnvs = []
+        for ind in range(self.stack):
+            hg = self.hg_module(
+                inter,
+                self.num_level,
+                self.dims,
+                self.modules,
+                name=name + '_hgs_' + str(ind))
+            cnv = _conv_norm(
+                hg,
+                3,
+                256,
+                bn_act='relu',
+                pad=1,
+                name=name + '_cnvs_' + str(ind))
+            cnvs.append(cnv)
+
+            if ind < self.stack - 1:
+                inter = _conv_norm(
+                    inter, 1, 256, name=name + '_inters__' +
+                    str(ind)) + _conv_norm(
+                        cnv, 1, 256, name=name + '_cnvs__' + str(ind))
+                inter = fluid.layers.relu(inter)
+                inter = residual_block(
+                    inter, 256, name=name + '_inters_' + str(ind))
+        return cnvs
+
+    def pre(self, x, name=None):
+        conv = _conv_norm(
+            x, 7, 128, stride=2, pad=3, bn_act='relu', name=name + '_0')
+        res1 = residual_block(conv, 256, stride=2, name=name + '_1')
+        res2 = residual_block(res1, 256, stride=2, name=name + '_2')
+        return res2
+
+    def hg_module(self,
+                  x,
+                  n=4,
+                  dims=[256, 256, 384, 384, 512],
+                  modules=[2, 2, 2, 2, 4],
+                  make_up_layer=make_layer,
+                  make_hg_layer=make_hg_layer,
+                  make_low_layer=make_layer,
+                  make_hg_layer_revr=make_layer_revr,
+                  make_unpool_layer=make_unpool_layer,
+                  name=None):
+        curr_mod = modules[0]
+        next_mod = modules[1]
+        curr_dim = dims[0]
+        next_dim = dims[1]
+        up1 = make_up_layer(
+            x, curr_dim, curr_dim, curr_mod, self.block, name=name + '_up1')
+        max1 = x
+        low1 = make_hg_layer(
+            max1, curr_dim, next_dim, curr_mod, self.block, name=name + '_low1')
+        low2 = self.hg_module(
+            low1,
+            n - 1,
+            dims[1:],
+            modules[1:],
+            make_up_layer=make_up_layer,
+            make_hg_layer=make_hg_layer,
+            make_low_layer=make_low_layer,
+            make_hg_layer_revr=make_hg_layer_revr,
+            make_unpool_layer=make_unpool_layer,
+            name=name + '_low2') if n > 1 else make_low_layer(
+                low1,
+                next_dim,
+                next_dim,
+                next_mod,
+                self.block,
+                name=name + '_low2')
+        low3 = make_hg_layer_revr(
+            low2, next_dim, curr_dim, curr_mod, self.block, name=name + '_low3')
+        up2 = make_unpool_layer(low3, curr_dim, name=name + '_up2')
+        merg = fluid.layers.elementwise_add(x=up1, y=up2, name=name + '_merg')
+        return merg

ppdet/modeling/ops.py

@@ -378,7 +378,7 @@ class MultiClassSoftNMS(object):
             fluid.default_main_program(),
             name='softnms_pred_result',
             dtype='float32',
-            shape=[6],
+            shape=[-1, 6],
             lod_level=1)
         fluid.layers.py_func(
             func=_soft_nms, x=[bboxes, scores], out=pred_result)

ppdet/optimizer.py

@@ -148,10 +148,12 @@ class OptimizerBuilder():
         self.optimizer = optimizer
 
     def __call__(self, learning_rate):
+        if self.regularizer:
             reg_type = self.regularizer['type'] + 'Decay'
             reg_factor = self.regularizer['factor']
             regularization = getattr(regularizer, reg_type)(reg_factor)
-
+        else:
+            regularization = None
         optim_args = self.optimizer.copy()
         optim_type = optim_args['type']
         del optim_args['type']

ppdet/utils/coco_eval.py

@@ -230,9 +230,10 @@ def bbox2out(results, clsid2catid, is_bbox_normalized=False):
     xywh_res = []
     for t in results:
         bboxes = t['bbox'][0]
+        if len(t['bbox'][1]) == 0: continue
         lengths = t['bbox'][1][0]
         im_ids = np.array(t['im_id'][0]).flatten()
-        if bboxes.shape == (1, 1) or bboxes is None:
+        if bboxes.shape == (1, 1) or bboxes is None or len(bboxes) == 0:
             continue
 
         k = 0

ppdet/utils/eval_utils.py

@@ -135,7 +135,8 @@ def eval_run(exe,
             mask_multi_scale_test = multi_scale_test and 'Mask' in cfg.architecture
 
             if multi_scale_test:
-                post_res = mstest_box_post_process(res, cfg)
+                post_res = mstest_box_post_process(res, multi_scale_test,
+                                                   cfg.num_classes)
                 res.update(post_res)
             if mask_multi_scale_test:
                 place = fluid.CUDAPlace(0) if cfg.use_gpu else fluid.CPUPlace()
@@ -156,10 +157,16 @@ def eval_run(exe,
             if 'mask' in res:
                 from ppdet.utils.post_process import mask_encode
                 res['mask'] = mask_encode(res, resolution)
+            post_config = getattr(cfg, 'PostProcess', None)
+            if 'Corner' in cfg.architecture and post_config is not None:
+                from ppdet.utils.post_process import corner_post_process
+                corner_post_process(res, post_config, cfg.num_classes)
             results.append(res)
             if iter_id % 100 == 0:
                 logger.info('Test iter {}'.format(iter_id))
             iter_id += 1
+            if len(res['bbox'][1]) == 0:
+                has_bbox = False
             images_num += len(res['bbox'][1][0]) if has_bbox else 1
     except (StopIteration, fluid.core.EOFException):
         loader.reset()

ppdet/utils/post_process.py

@@ -38,7 +38,7 @@ def box_flip(boxes, im_shape):
 def nms(dets, thresh):
     """Apply classic DPM-style greedy NMS."""
     if dets.shape[0] == 0:
-        return []
+        return dets[[], :]
     scores = dets[:, 0]
     x1 = dets[:, 1]
     y1 = dets[:, 2]
@@ -86,8 +86,40 @@ def nms(dets, thresh):
             ovr = inter / (iarea + areas[j] - inter)
             if ovr >= thresh:
                 suppressed[j] = 1
+    keep = np.where(suppressed == 0)[0]
+    dets = dets[keep, :]
+    return dets
 
-    return np.where(suppressed == 0)[0]
+
+def soft_nms(dets, sigma, thres):
+    dets_final = []
+    while len(dets) > 0:
+        maxpos = np.argmax(dets[:, 0])
+        dets_final.append(dets[maxpos].copy())
+        ts, tx1, ty1, tx2, ty2 = dets[maxpos]
+        scores = dets[:, 0]
+        # force remove bbox at maxpos
+        scores[maxpos] = -1
+        x1 = dets[:, 1]
+        y1 = dets[:, 2]
+        x2 = dets[:, 3]
+        y2 = dets[:, 4]
+        areas = (x2 - x1 + 1) * (y2 - y1 + 1)
+        xx1 = np.maximum(tx1, x1)
+        yy1 = np.maximum(ty1, y1)
+        xx2 = np.minimum(tx2, x2)
+        yy2 = np.minimum(ty2, y2)
+        w = np.maximum(0.0, xx2 - xx1 + 1)
+        h = np.maximum(0.0, yy2 - yy1 + 1)
+        inter = w * h
+        ovr = inter / (areas + areas[maxpos] - inter)
+        weight = np.exp(-(ovr * ovr) / sigma)
+        scores = scores * weight
+        idx_keep = np.where(scores >= thres)
+        dets[:, 0] = scores
+        dets = dets[idx_keep]
+    dets_final = np.array(dets_final).reshape(-1, 5)
+    return dets_final
 
 
 def bbox_area(box):
@@ -128,39 +160,49 @@ def box_voting(nms_dets, dets, vote_thresh):
     return top_dets
 
 
-def get_nms_result(boxes, scores, cfg):
-    cls_boxes = [[] for _ in range(cfg.num_classes)]
-    for j in range(1, cfg.num_classes):
-        inds = np.where(scores[:, j] > cfg.MultiScaleTEST['score_thresh'])[0]
-        scores_j = scores[inds, j]
-        boxes_j = boxes[inds, j * 4:(j + 1) * 4]
+def get_nms_result(boxes,
+                   scores,
+                   config,
+                   num_classes,
+                   background_label=0,
+                   labels=None):
+    has_labels = labels is not None
+    cls_boxes = [[] for _ in range(num_classes)]
+    start_idx = 1 if background_label == 0 else 0
+    for j in range(start_idx, num_classes):
+        inds = np.where(labels == j)[0] if has_labels else np.where(
+            scores[:, j] > config['score_thresh'])[0]
+        scores_j = scores[inds] if has_labels else scores[inds, j]
+        boxes_j = boxes[inds, :] if has_labels else boxes[inds, j * 4:(j + 1) *
+                                                          4]
         dets_j = np.hstack((scores_j[:, np.newaxis], boxes_j)).astype(
             np.float32, copy=False)
-        keep = nms(dets_j, cfg.MultiScaleTEST['nms_thresh'])
-        nms_dets = dets_j[keep, :]
-        if cfg.MultiScaleTEST['enable_voting']:
-            nms_dets = box_voting(nms_dets, dets_j,
-                                  cfg.MultiScaleTEST['vote_thresh'])
+        if config.get('use_soft_nms', False):
+            nms_dets = soft_nms(dets_j, config['sigma'], config['nms_thresh'])
+        else:
+            nms_dets = nms(dets_j, config['nms_thresh'])
+        if config.get('enable_voting', False):
+            nms_dets = box_voting(nms_dets, dets_j, config['vote_thresh'])
         #add labels
-        label = np.array([j for _ in range(len(keep))])
+        label = np.array([j for _ in range(len(nms_dets))])
         nms_dets = np.hstack((label[:, np.newaxis], nms_dets)).astype(
             np.float32, copy=False)
         cls_boxes[j] = nms_dets
     # Limit to max_per_image detections **over all classes**
     image_scores = np.hstack(
-        [cls_boxes[j][:, 1] for j in range(1, cfg.num_classes)])
-    if len(image_scores) > cfg.MultiScaleTEST['detections_per_im']:
-        image_thresh = np.sort(image_scores)[-cfg.MultiScaleTEST[
-            'detections_per_im']]
-        for j in range(1, cfg.num_classes):
+        [cls_boxes[j][:, 1] for j in range(start_idx, num_classes)])
+    if len(image_scores) > config['detections_per_im']:
+        image_thresh = np.sort(image_scores)[-config['detections_per_im']]
+        for j in range(start_idx, num_classes):
             keep = np.where(cls_boxes[j][:, 1] >= image_thresh)[0]
             cls_boxes[j] = cls_boxes[j][keep, :]
 
-    im_results = np.vstack([cls_boxes[j] for j in range(1, cfg.num_classes)])
+    im_results = np.vstack(
+        [cls_boxes[j] for j in range(start_idx, num_classes)])
     return im_results
 
 
-def mstest_box_post_process(result, cfg):
+def mstest_box_post_process(result, config, num_classes):
     """
     Multi-scale Test
     Only available for batch_size=1 now.
@@ -173,7 +215,7 @@ def mstest_box_post_process(result, cfg):
     for k in result.keys():
         if 'bbox' in k:
             boxes = result[k][0]
-            boxes = np.reshape(boxes, (-1, 4 * cfg.num_classes))
+            boxes = np.reshape(boxes, (-1, 4 * num_classes))
             scores = result['score' + k[4:]][0]
             if 'flip' in k:
                 boxes = box_flip(boxes, im_shape)
@@ -183,7 +225,7 @@ def mstest_box_post_process(result, cfg):
 
     ms_boxes = np.concatenate(ms_boxes)
     ms_scores = np.concatenate(ms_scores)
-    bbox_pred = get_nms_result(ms_boxes, ms_scores, cfg)
+    bbox_pred = get_nms_result(ms_boxes, ms_scores, config, num_classes)
     post_bbox.update({'bbox': (bbox_pred, [[len(bbox_pred)]])})
     if use_flip:
         bbox = bbox_pred[:, 2:]
@@ -271,3 +313,15 @@ def mask_encode(results, resolution, thresh_binarize=0.5):
                     im_mask[:, :, np.newaxis], order='F'))[0]
             segms.append(segm)
     return segms
+
+
+def corner_post_process(results, config, num_classes):
+    detections = results['bbox'][0]
+    keep_inds = (detections[:, 1] > -1)
+    detections = detections[keep_inds]
+    labels = detections[:, 0]
+    scores = detections[:, 1]
+    boxes = detections[:, 2:6]
+    cls_boxes = get_nms_result(
+        boxes, scores, config, num_classes, background_label=-1, labels=labels)
+    results.update({'bbox': (cls_boxes, [[len(cls_boxes)]])})