generate_proposal_labels_op.cc 21.9 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515
/* Copyright (c) 2018 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 <math.h>
#include <algorithm>
#include <string>
#include <vector>
#include "paddle/fluid/framework/op_registry.h"
#include "paddle/fluid/operators/gather.h"
#include "paddle/fluid/operators/math/concat.h"
#include "paddle/fluid/operators/math/math_function.h"

namespace paddle {
namespace operators {

using Tensor = framework::Tensor;
using LoDTensor = framework::LoDTensor;
const int kBoxDim = 4;

template <typename T>
void AppendRois(LoDTensor* out, int64_t offset, Tensor* to_add) {
  auto* out_data = out->data<T>();
  auto* to_add_data = to_add->data<T>();
  memcpy(out_data + offset, to_add_data, to_add->numel() * sizeof(T));
}

class GenerateProposalLabelsOp : public framework::OperatorWithKernel {
 public:
  using framework::OperatorWithKernel::OperatorWithKernel;

  void InferShape(framework::InferShapeContext* ctx) const override {
    PADDLE_ENFORCE(ctx->HasInput("RpnRois"),
                   "Input(RpnRois) shouldn't be null.");
    PADDLE_ENFORCE(ctx->HasInput("GtClasses"),
                   "Input(GtClasses) shouldn't be null.");
    PADDLE_ENFORCE(ctx->HasInput("GtBoxes"),
                   "Input(GtBoxes) shouldn't be null.");
    PADDLE_ENFORCE(ctx->HasInput("ImScales"),
                   "Input(ImScales) shouldn't be null.");

    PADDLE_ENFORCE(ctx->HasOutput("Rois"),
                   "Output(Rois) of RpnTargetAssignOp should not be null");
    PADDLE_ENFORCE(
        ctx->HasOutput("LabelsInt32"),
        "Output(LabelsInt32) of RpnTargetAssignOp should not be null");
    PADDLE_ENFORCE(
        ctx->HasOutput("BboxTargets"),
        "Output(BboxTargets) of RpnTargetAssignOp should not be null");
    PADDLE_ENFORCE(
        ctx->HasOutput("BboxInsideWeights"),
        "Output(BboxInsideWeights) of RpnTargetAssignOp should not be null");
    PADDLE_ENFORCE(
        ctx->HasOutput("BboxOutsideWeights"),
        "Output(BboxOutsideWeights) of RpnTargetAssignOp should not be null");

    auto rpn_rois_dims = ctx->GetInputDim("RpnRois");
    auto gt_classes_dims = ctx->GetInputDim("GtClasses");
    auto gt_boxes_dims = ctx->GetInputDim("GtBoxes");
    auto im_scales_dims = ctx->GetInputDim("ImScales");

    PADDLE_ENFORCE_EQ(rpn_rois_dims.size(), 2,
                      "The rank of Input(RpnRois) must be 2.");
    PADDLE_ENFORCE_EQ(gt_classes_dims.size(), 1,
                      "The rank of Input(GtClasses) must be 1.");
    PADDLE_ENFORCE_EQ(gt_boxes_dims.size(), 2,
                      "The rank of Input(GtBoxes) must be 2.");
    PADDLE_ENFORCE_EQ(im_scales_dims.size(), 1,
                      "The rank of Input(ImScales) must be 1.");

    int class_nums = ctx->Attrs().Get<int>("class_nums");

    ctx->SetOutputDim("Rois", {-1, 4});
    ctx->SetOutputDim("LabelsInt32", {-1});
    ctx->SetOutputDim("BboxTargets", {-1, 4 * class_nums});
    ctx->SetOutputDim("BboxInsideWeights", {-1, 4 * class_nums});
    ctx->SetOutputDim("BboxOutsideWeights", {-1, 4 * class_nums});
  }

 protected:
  framework::OpKernelType GetExpectedKernelType(
      const framework::ExecutionContext& ctx) const override {
    auto data_type = framework::GetDataTypeOfVar(ctx.InputVar("RpnRois"));
    return framework::OpKernelType(data_type, platform::CPUPlace());
  }
};

template <typename T>
void Concat(const platform::CPUDeviceContext& context,
            const Tensor& in_tensor_a, const Tensor& in_tensor_b,
            Tensor* out_tensor) {
  int axis = 0;
  std::vector<Tensor> inputs;
  inputs.emplace_back(in_tensor_a);
  inputs.emplace_back(in_tensor_b);
  math::ConcatFunctor<platform::CPUDeviceContext, T> concat_functor;
  concat_functor(context, inputs, axis, out_tensor);
}

template <typename T>
void BboxOverlaps(const Tensor& r_boxes, const Tensor& c_boxes,
                  Tensor* overlaps) {
  auto r_boxes_et = framework::EigenTensor<T, 2>::From(r_boxes);
  auto c_boxes_et = framework::EigenTensor<T, 2>::From(c_boxes);
  auto overlaps_et = framework::EigenTensor<T, 2>::From(*overlaps);
  int r_num = r_boxes.dims()[0];
  int c_num = c_boxes.dims()[0];
  auto zero = static_cast<T>(0.0);
  T r_box_area, c_box_area, x_min, y_min, x_max, y_max, inter_w, inter_h,
      inter_area;
  for (int i = 0; i < r_num; ++i) {
    r_box_area = (r_boxes_et(i, 2) - r_boxes_et(i, 0) + 1) *
                 (r_boxes_et(i, 3) - r_boxes_et(i, 1) + 1);
    for (int j = 0; j < c_num; ++j) {
      c_box_area = (c_boxes_et(j, 2) - c_boxes_et(j, 0) + 1) *
                   (c_boxes_et(j, 3) - c_boxes_et(j, 1) + 1);
      x_min = std::max(r_boxes_et(i, 0), c_boxes_et(j, 0));
      y_min = std::max(r_boxes_et(i, 1), c_boxes_et(j, 1));
      x_max = std::min(r_boxes_et(i, 2), c_boxes_et(j, 2));
      y_max = std::min(r_boxes_et(i, 3), c_boxes_et(j, 3));
      inter_w = std::max(x_max - x_min + 1, zero);
      inter_h = std::max(y_max - y_min + 1, zero);
      inter_area = inter_w * inter_h;
      overlaps_et(i, j) = inter_area / (r_box_area + c_box_area - inter_area);
    }
  }
}

template <typename T>
void BoxToDelta(int box_num, const Tensor& ex_boxes, const Tensor& gt_boxes,
                const std::vector<float>& weights, Tensor* box_delta) {
  auto ex_boxes_et = framework::EigenTensor<T, 2>::From(ex_boxes);
  auto gt_boxes_et = framework::EigenTensor<T, 2>::From(gt_boxes);
  auto box_delta_et = framework::EigenTensor<T, 2>::From(*box_delta);
  T ex_w, ex_h, ex_ctr_x, ex_ctr_y, gt_w, gt_h, gt_ctr_x, gt_ctr_y;
  for (int64_t i = 0; i < box_num; ++i) {
    ex_w = ex_boxes_et(i, 2) - ex_boxes_et(i, 0) + 1;
    ex_h = ex_boxes_et(i, 3) - ex_boxes_et(i, 1) + 1;
    ex_ctr_x = ex_boxes_et(i, 0) + 0.5 * ex_w;
    ex_ctr_y = ex_boxes_et(i, 1) + 0.5 * ex_h;

    gt_w = gt_boxes_et(i, 2) - gt_boxes_et(i, 0) + 1;
    gt_h = gt_boxes_et(i, 3) - gt_boxes_et(i, 1) + 1;
    gt_ctr_x = gt_boxes_et(i, 0) + 0.5 * gt_w;
    gt_ctr_y = gt_boxes_et(i, 1) + 0.5 * gt_h;

    box_delta_et(i, 0) = (gt_ctr_x - ex_ctr_x) / ex_w / weights[0];
    box_delta_et(i, 1) = (gt_ctr_y - ex_ctr_y) / ex_h / weights[1];
    box_delta_et(i, 2) = log(gt_w / ex_w) / ex_w / weights[2];
    box_delta_et(i, 3) = log(gt_h / ex_h) / ex_h / weights[3];
  }
}

template <typename T>
std::vector<std::vector<int>> SampleFgBgGt(
    const platform::CPUDeviceContext& context, Tensor* iou,
    const int batch_size_per_im, const float fg_fraction, const float fg_thresh,
    const float bg_thresh_hi, const float bg_thresh_lo,
    std::minstd_rand engine) {
  std::vector<int> fg_inds;
  std::vector<int> bg_inds;
  std::vector<int> gt_inds;
  T* proposal_to_gt_overlaps = iou->mutable_data<T>(context.GetPlace());
  int64_t row = iou->dims()[0];
  int64_t col = iou->dims()[1];
  float epsilon = 0.00001;

  // Follow the Faster RCNN's implementation
  for (int64_t i = 0; i < row; ++i) {
    const T* v = proposal_to_gt_overlaps + i * col;
    T max_overlap = *std::max_element(v, v + col);
    if (max_overlap > fg_thresh) {
      for (int64_t j = 0; j < col; ++j) {
        T val = proposal_to_gt_overlaps[i * col + j];
        auto diff = std::abs(max_overlap - val);
        if (diff < epsilon) {
          fg_inds.emplace_back(i);
          gt_inds.emplace_back(j);
          break;
        }
      }
    } else {
      if ((max_overlap >= bg_thresh_lo) && (max_overlap < bg_thresh_hi)) {
        bg_inds.emplace_back(i);
      }
    }
  }

  // Reservoir Sampling
  int fg_rois_per_im = std::floor(batch_size_per_im * fg_fraction);
  int fg_rois_this_image = fg_inds.size();
  int fg_rois_per_this_image = std::min(fg_rois_per_im, fg_rois_this_image);
  std::uniform_real_distribution<float> uniform(0, 1);
  const int64_t fg_size = static_cast<int64_t>(fg_inds.size());
  if (fg_size > fg_rois_per_this_image) {
    for (int64_t i = fg_rois_per_this_image; i < fg_size; ++i) {
      int rng_ind = std::floor(uniform(engine) * i);
      if (rng_ind < fg_rois_per_this_image) {
        std::iter_swap(fg_inds.begin() + rng_ind, fg_inds.begin() + i);
        std::iter_swap(gt_inds.begin() + rng_ind, gt_inds.begin() + i);
      }
    }
  }
  std::vector<int> new_fg_inds(fg_inds.begin(),
                               fg_inds.begin() + fg_rois_per_this_image);
  std::vector<int> new_gt_inds(gt_inds.begin(),
                               gt_inds.begin() + fg_rois_per_this_image);

  int bg_rois_per_image = batch_size_per_im - fg_rois_per_this_image;
  int bg_rois_this_image = bg_inds.size();
  int bg_rois_per_this_image = std::min(bg_rois_per_image, bg_rois_this_image);
  const int64_t bg_size = static_cast<int64_t>(bg_inds.size());
  if (bg_size > bg_rois_per_this_image) {
    for (int64_t i = bg_rois_per_this_image; i < bg_size; ++i) {
      int rng_ind = std::floor(uniform(engine) * i);
      if (rng_ind < fg_rois_per_this_image)
        std::iter_swap(bg_inds.begin() + rng_ind, bg_inds.begin() + i);
    }
  }
  std::vector<int> new_bg_inds(bg_inds.begin(),
                               bg_inds.begin() + bg_rois_per_this_image);
  std::vector<std::vector<int>> res;
  res.emplace_back(new_fg_inds);
  res.emplace_back(new_bg_inds);
  res.emplace_back(new_gt_inds);
  return res;
}

template <typename T>
void GatherBoxesLabels(const platform::CPUDeviceContext& context,
                       const Tensor& boxes, const Tensor& gt_boxes,
                       const Tensor& gt_classes,
                       const std::vector<int>& fg_inds,
                       const std::vector<int>& bg_inds,
                       const std::vector<int>& gt_inds, Tensor* sampled_boxes,
                       Tensor* sampled_labels, Tensor* sampled_gts) {
  int fg_num = fg_inds.size();
  int bg_num = bg_inds.size();
  int gt_num = fg_num + bg_num;
  Tensor fg_inds_t, bg_inds_t, gt_box_inds_t, gt_label_inds_t;
  int* fg_inds_data = fg_inds_t.mutable_data<int>({fg_num}, context.GetPlace());
  int* bg_inds_data = bg_inds_t.mutable_data<int>({bg_num}, context.GetPlace());
  int* gt_box_inds_data =
      gt_box_inds_t.mutable_data<int>({gt_num}, context.GetPlace());
  int* gt_label_inds_data =
      gt_label_inds_t.mutable_data<int>({fg_num}, context.GetPlace());
  std::copy(fg_inds.begin(), fg_inds.end(), fg_inds_data);
  std::copy(bg_inds.begin(), bg_inds.end(), bg_inds_data);
  std::copy(gt_inds.begin(), gt_inds.end(), gt_box_inds_data);
  std::copy(gt_inds.begin(), gt_inds.end(), gt_label_inds_data);

  Tensor fg_boxes, bg_boxes, fg_labels, bg_labels;
  fg_boxes.mutable_data<T>({fg_num, kBoxDim}, context.GetPlace());
  CPUGather<T>(context, boxes, fg_inds_t, &fg_boxes);
  bg_boxes.mutable_data<T>({bg_num, kBoxDim}, context.GetPlace());
  CPUGather<T>(context, boxes, bg_inds_t, &bg_boxes);
  Concat<T>(context, fg_boxes, bg_boxes, sampled_boxes);
  CPUGather<T>(context, gt_boxes, gt_box_inds_t, sampled_gts);
  fg_labels.mutable_data<int>({fg_num}, context.GetPlace());
  CPUGather<int>(context, gt_classes, gt_label_inds_t, &fg_labels);
  bg_labels.mutable_data<int>({bg_num}, context.GetPlace());
  math::set_constant(context, &bg_labels, 0);
  Concat<int>(context, fg_labels, bg_labels, sampled_labels);
}

template <typename T>
std::vector<Tensor> SampleRoisForOneImage(
    const platform::CPUDeviceContext& context, Tensor* rpn_rois,
    Tensor* gt_classes, Tensor* gt_boxes, Tensor* im_scale,
    const int batch_size_per_im, const float fg_fraction, const float fg_thresh,
    const float bg_thresh_hi, const float bg_thresh_lo,
    const std::vector<float>& bbox_reg_weights, const int class_nums,
    std::minstd_rand engine) {
  auto rpn_rois_et = framework::EigenTensor<T, 2>::From(*rpn_rois);
  auto im_scale_data = im_scale->data<T>()[0];
  rpn_rois_et = rpn_rois_et / im_scale_data;

  Tensor boxes;
  int proposals_num = gt_boxes->dims()[0] + rpn_rois->dims()[0];
  boxes.mutable_data<T>({proposals_num, kBoxDim}, context.GetPlace());
  Concat<T>(context, *gt_boxes, *rpn_rois, &boxes);

  // Overlaps
  Tensor proposal_to_gt_overlaps;
  proposal_to_gt_overlaps.mutable_data<T>({proposals_num, gt_boxes->dims()[0]},
                                          context.GetPlace());
  BboxOverlaps<T>(boxes, *gt_boxes, &proposal_to_gt_overlaps);

  // Generate proposal index
  std::vector<std::vector<int>> fg_bg_gt = SampleFgBgGt<T>(
      context, &proposal_to_gt_overlaps, batch_size_per_im, fg_fraction,
      fg_thresh, bg_thresh_hi, bg_thresh_lo, engine);
  std::vector<int> fg_inds = fg_bg_gt[0];
  std::vector<int> bg_inds = fg_bg_gt[1];
  std::vector<int> gt_inds = fg_bg_gt[2];

  // Gather boxes and labels
  Tensor sampled_boxes, sampled_labels, sampled_gts;
  int boxes_num = fg_inds.size() + bg_inds.size();
  framework::DDim bbox_dim({boxes_num, kBoxDim});
  sampled_boxes.mutable_data<T>(bbox_dim, context.GetPlace());
  sampled_labels.mutable_data<int>({boxes_num}, context.GetPlace());
  sampled_gts.mutable_data<T>(bbox_dim, context.GetPlace());
  GatherBoxesLabels<T>(context, boxes, *gt_boxes, *gt_classes, fg_inds, bg_inds,
                       gt_inds, &sampled_boxes, &sampled_labels, &sampled_gts);

  // Compute targets
  Tensor bbox_targets_single;
  bbox_targets_single.mutable_data<T>(bbox_dim, context.GetPlace());
  BoxToDelta<T>(boxes_num, sampled_boxes, sampled_gts, bbox_reg_weights,
                &bbox_targets_single);

  // Scale rois
  Tensor sampled_rois;
  sampled_rois.mutable_data<T>(sampled_boxes.dims(), context.GetPlace());
  auto sampled_rois_et = framework::EigenTensor<T, 2>::From(sampled_rois);
  auto sampled_boxes_et = framework::EigenTensor<T, 2>::From(sampled_boxes);
  sampled_rois_et = sampled_boxes_et * im_scale_data;

  // Expand box targets
  Tensor bbox_targets, bbox_inside_weights, bbox_outside_weights;
  framework::DDim bbox_expand_dim({boxes_num, kBoxDim * class_nums});
  bbox_targets.mutable_data<T>(bbox_expand_dim, context.GetPlace());
  bbox_inside_weights.mutable_data<T>(bbox_expand_dim, context.GetPlace());
  bbox_outside_weights.mutable_data<T>(bbox_expand_dim, context.GetPlace());
  math::set_constant(context, &bbox_targets, 0.0);
  math::set_constant(context, &bbox_inside_weights, 0.0);
  math::set_constant(context, &bbox_outside_weights, 0.0);

  auto* bbox_targets_single_data = bbox_targets_single.data<T>();
  auto* sampled_labels_data = sampled_labels.data<int>();
  auto* bbox_targets_data = bbox_targets.data<T>();
  auto* bbox_inside_weights_data = bbox_inside_weights.data<T>();
  auto* bbox_outside_weights_data = bbox_outside_weights.data<T>();
  int width = kBoxDim * class_nums;
  for (int64_t i = 0; i < boxes_num; ++i) {
    int label = sampled_labels_data[i];
    if (label > 0) {
      int dst_idx = i * width + kBoxDim * label;
      int src_idx = kBoxDim * i;
      bbox_targets_data[dst_idx] = bbox_targets_single_data[src_idx];
      bbox_targets_data[dst_idx + 1] = bbox_targets_single_data[src_idx + 1];
      bbox_targets_data[dst_idx + 2] = bbox_targets_single_data[src_idx + 2];
      bbox_targets_data[dst_idx + 3] = bbox_targets_single_data[src_idx + 3];
      bbox_inside_weights_data[dst_idx] = 1;
      bbox_inside_weights_data[dst_idx + 1] = 1;
      bbox_inside_weights_data[dst_idx + 2] = 1;
      bbox_inside_weights_data[dst_idx + 3] = 1;
      bbox_outside_weights_data[dst_idx] = 1;
      bbox_outside_weights_data[dst_idx + 1] = 1;
      bbox_outside_weights_data[dst_idx + 2] = 1;
      bbox_outside_weights_data[dst_idx + 3] = 1;
    }
  }
  std::vector<Tensor> res;
  res.emplace_back(sampled_rois);
  res.emplace_back(sampled_labels);
  res.emplace_back(bbox_targets);
  res.emplace_back(bbox_inside_weights);
  res.emplace_back(bbox_outside_weights);
  return res;
}

template <typename T>
class GenerateProposalLabelsKernel : public framework::OpKernel<T> {
 public:
  void Compute(const framework::ExecutionContext& context) const override {
    auto* rpn_rois = context.Input<LoDTensor>("RpnRois");
    auto* gt_classes = context.Input<LoDTensor>("GtClasses");
    auto* gt_boxes = context.Input<LoDTensor>("GtBoxes");
    auto* im_scales = context.Input<LoDTensor>("ImScales");

    auto* rois = context.Output<LoDTensor>("Rois");
    auto* labels_int32 = context.Output<LoDTensor>("LabelsInt32");
    auto* bbox_targets = context.Output<LoDTensor>("BboxTargets");
    auto* bbox_inside_weights = context.Output<LoDTensor>("BboxInsideWeights");
    auto* bbox_outside_weights =
        context.Output<LoDTensor>("BboxOutsideWeights");

    int batch_size_per_im = context.Attr<int>("batch_size_per_im");
    float fg_fraction = context.Attr<float>("fg_fraction");
    float fg_thresh = context.Attr<float>("fg_thresh");
    float bg_thresh_hi = context.Attr<float>("bg_thresh_hi");
    float bg_thresh_lo = context.Attr<float>("bg_thresh_lo");
    std::vector<float> bbox_reg_weights =
        context.Attr<std::vector<float>>("bbox_reg_weights");
    int class_nums = context.Attr<int>("class_nums");

    PADDLE_ENFORCE_EQ(rpn_rois->lod().size(), 1UL,
                      "GenerateProposalLabelsOp rpn_rois needs 1 level of LoD");
    PADDLE_ENFORCE_EQ(
        gt_classes->lod().size(), 1UL,
        "GenerateProposalLabelsOp gt_classes needs 1 level of LoD");
    PADDLE_ENFORCE_EQ(gt_boxes->lod().size(), 1UL,
                      "GenerateProposalLabelsOp gt_boxes needs 1 level of LoD");
    int64_t n = static_cast<int64_t>(rpn_rois->lod().back().size() - 1);

    rois->mutable_data<T>({n * batch_size_per_im, kBoxDim}, context.GetPlace());
    labels_int32->mutable_data<int>({n * batch_size_per_im},
                                    context.GetPlace());
    bbox_targets->mutable_data<T>({n * batch_size_per_im, kBoxDim * class_nums},
                                  context.GetPlace());
    bbox_inside_weights->mutable_data<T>(
        {n * batch_size_per_im, kBoxDim * class_nums}, context.GetPlace());
    bbox_outside_weights->mutable_data<T>(
        {n * batch_size_per_im, kBoxDim * class_nums}, context.GetPlace());

    std::random_device rnd;
    std::minstd_rand engine;
    int seed =
        context.Attr<bool>("fix_seed") ? context.Attr<int>("seed") : rnd();
    engine.seed(seed);

    framework::LoD lod;
    std::vector<size_t> lod0(1, 0);

    int64_t num_rois = 0;
    auto& dev_ctx = context.device_context<platform::CPUDeviceContext>();

    auto rpn_rois_lod = rpn_rois->lod().back();
    auto gt_classes_lod = gt_classes->lod().back();
    auto gt_boxes_lod = gt_boxes->lod().back();
    for (size_t i = 0; i < n; ++i) {
      Tensor rpn_rois_slice =
          rpn_rois->Slice(rpn_rois_lod[i], rpn_rois_lod[i + 1]);
      Tensor gt_classes_slice =
          gt_classes->Slice(gt_classes_lod[i], gt_classes_lod[i + 1]);
      Tensor gt_boxes_slice =
          gt_boxes->Slice(gt_boxes_lod[i], gt_boxes_lod[i + 1]);
      Tensor im_scales_slice = im_scales->Slice(i, i + 1);
      std::vector<Tensor> tensor_output = SampleRoisForOneImage<T>(
          dev_ctx, &rpn_rois_slice, &gt_classes_slice, &gt_boxes_slice,
          &im_scales_slice, batch_size_per_im, fg_fraction, fg_thresh,
          bg_thresh_hi, bg_thresh_lo, bbox_reg_weights, class_nums, engine);
      Tensor sampled_rois = tensor_output[0];
      Tensor sampled_labels_int32 = tensor_output[1];
      Tensor sampled_bbox_targets = tensor_output[2];
      Tensor sampled_bbox_inside_weights = tensor_output[3];
      Tensor sampled_bbox_outside_weights = tensor_output[4];

      AppendRois<T>(rois, kBoxDim * num_rois, &sampled_rois);
      AppendRois<int>(labels_int32, num_rois, &sampled_labels_int32);
      AppendRois<T>(bbox_targets, kBoxDim * num_rois * class_nums,
                    &sampled_bbox_targets);
      AppendRois<T>(bbox_inside_weights, kBoxDim * num_rois * class_nums,
                    &sampled_bbox_inside_weights);
      AppendRois<T>(bbox_outside_weights, kBoxDim * num_rois * class_nums,
                    &sampled_bbox_outside_weights);

      num_rois += sampled_rois.dims()[0];
      lod0.emplace_back(num_rois);
    }

    lod.emplace_back(lod0);
    rois->set_lod(lod);
    labels_int32->set_lod(lod);
    bbox_targets->set_lod(lod);
    bbox_inside_weights->set_lod(lod);
    bbox_outside_weights->set_lod(lod);
    rois->Resize({num_rois, kBoxDim});
    labels_int32->Resize({num_rois});
    bbox_targets->Resize({num_rois, kBoxDim * class_nums});
    bbox_inside_weights->Resize({num_rois, kBoxDim * class_nums});
    bbox_outside_weights->Resize({num_rois, kBoxDim * class_nums});
  }
};

class GenerateProposalLabelsOpMaker : public framework::OpProtoAndCheckerMaker {
 public:
  void Make() override {
    // TODO(buxingyuan): Add Document
    AddInput("RpnRois", "RpnRois.");
    AddInput("GtClasses", "GtClasses.");
    AddInput("GtBoxes", "GtBoxes.");
    AddInput("ImScales", "ImScales.");

    AddOutput("Rois", "Rois.");
    AddOutput("LabelsInt32", "LabelsInt32.");
    AddOutput("BboxTargets", "BboxTargets.");
    AddOutput("BboxInsideWeights", "BboxInsideWeights.");
    AddOutput("BboxOutsideWeights", "BboxOutsideWeights.");

    AddAttr<int>("batch_size_per_im", "batch_size_per_im");
    AddAttr<float>("fg_fraction", "fg_fraction");
    AddAttr<float>("fg_thresh", "fg_thresh");
    AddAttr<float>("bg_thresh_hi", "bg_thresh_hi");
    AddAttr<float>("bg_thresh_lo", "bg_thresh_lo");
    AddAttr<std::vector<float>>("bbox_reg_weights", "bbox_reg_weights");
    AddAttr<int>("class_nums", "class_nums");
    AddAttr<bool>("fix_seed", "fix_seed").SetDefault(false);
    AddAttr<int>("seed", "seed").SetDefault(0);

    AddComment(R"DOC(
Generate Proposals Labels Operator.
)DOC");
  }
};

}  // namespace operators
}  // namespace paddle

namespace ops = paddle::operators;
REGISTER_OPERATOR(generate_proposal_labels, ops::GenerateProposalLabelsOp,
                  ops::GenerateProposalLabelsOpMaker,
                  paddle::framework::EmptyGradOpMaker);
REGISTER_OP_CPU_KERNEL(generate_proposal_labels,
                       ops::GenerateProposalLabelsKernel<float>,
                       ops::GenerateProposalLabelsKernel<double>);