Merge pull request #7679 from wanghaox/hard_example

add mine_hard_examples operator

paddle/operators/mine_hard_examples_op.cc

+/* Copyright (c) 2018 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/framework/eigen.h"
+#include "paddle/framework/op_registry.h"
+
+namespace paddle {
+namespace operators {
+
+enum MiningType { kNone = 0, kMaxNegative, kHardExample };
+
+template <typename T>
+bool SortScoreDescend(const std::pair<float, T>& pair1,
+                      const std::pair<float, T>& pair2) {
+  return pair1.first > pair2.first;
+}
+
+inline bool IsEligibleMining(const MiningType mining_type, const int match_idx,
+                             const float match_dist,
+                             const float neg_dist_threshold) {
+  if (mining_type == MiningType::kMaxNegative) {
+    return match_idx == -1 && match_dist < neg_dist_threshold;
+  } else if (mining_type == MiningType::kHardExample) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+inline MiningType GetMiningType(std::string str) {
+  if (str == "max_negative") {
+    return MiningType::kMaxNegative;
+  } else if (str == "hard_example") {
+    return MiningType::kHardExample;
+  } else {
+    return MiningType::kNone;
+  }
+}
+
+template <typename DeviceContext, typename T>
+class MineHardExamplesKernel : public framework::OpKernel<T> {
+ public:
+  void Compute(const framework::ExecutionContext& ctx) const override {
+    auto* in_cls_loss = ctx.Input<framework::Tensor>("ClsLoss");
+    auto* in_loc_loss = ctx.Input<framework::Tensor>("LocLoss");
+    auto* in_matched_indices = ctx.Input<framework::Tensor>("MatchIndices");
+    auto* in_match_dist = ctx.Input<framework::Tensor>("MatchDist");
+    float neg_pos_ratio = ctx.Attr<float>("neg_pos_ratio");
+    T neg_dist_threshold =
+        static_cast<T>(ctx.Attr<float>("neg_dist_threshold"));
+    int sample_size = ctx.Attr<int>("sample_size");
+    MiningType mining_type =
+        GetMiningType(ctx.Attr<std::string>("mining_type"));
+
+    auto out_neg_indices = ctx.Output<framework::LoDTensor>("NegIndices");
+    auto out_match_indices =
+        ctx.Output<framework::Tensor>("UpdatedMatchIndices");
+
+    framework::Copy(*in_matched_indices, ctx.GetPlace(), out_match_indices);
+
+    int batch_size = in_matched_indices->dims()[0];
+    int prior_num = in_matched_indices->dims()[1];
+
+    auto match_indices = framework::EigenMatrix<int>::From(*in_matched_indices);
+
+    auto match_indices_et =
+        framework::EigenMatrix<int>::From(*out_match_indices);
+
+    auto match_dist = framework::EigenMatrix<T>::From(*in_match_dist);
+
+    const T* cls_loss = in_cls_loss->data<T>();
+    const T* loc_loss = nullptr;
+    if (in_loc_loss) {
+      loc_loss = in_loc_loss->data<T>();
+    }
+
+    std::vector<std::vector<int>> all_neg_indices;
+    std::vector<size_t> batch_starts = {0};
+    for (int n = 0; n < batch_size; ++n) {
+      std::vector<std::pair<T, size_t>> loss_idx;
+      int neg_sel = 0;
+      for (int m = 0; m < prior_num; ++m) {
+        if (IsEligibleMining(mining_type, match_indices(n, m), match_dist(n, m),
+                             neg_dist_threshold)) {
+          T loss = cls_loss[n * prior_num + m];
+          if (mining_type == MiningType::kHardExample && loc_loss != nullptr) {
+            loss = cls_loss[n * prior_num + m] + loc_loss[n * prior_num + m];
+          }
+          loss_idx.push_back(std::make_pair(loss, m));
+          ++neg_sel;
+        }
+      }
+
+      if (mining_type == MiningType::kMaxNegative) {
+        int num_pos = 0;
+        for (int m = 0; m < prior_num; ++m) {
+          if (match_indices(n, m) != -1) ++num_pos;
+        }
+        neg_sel = std::min(static_cast<int>(num_pos * neg_pos_ratio), neg_sel);
+      } else if (mining_type == MiningType::kHardExample) {
+        neg_sel = std::min(sample_size, neg_sel);
+      }
+
+      std::sort(loss_idx.begin(), loss_idx.end(), SortScoreDescend<size_t>);
+      std::set<int> sel_indices;
+      std::vector<int> neg_indices;
+      std::transform(loss_idx.begin(), loss_idx.begin() + neg_sel,
+                     std::inserter(sel_indices, sel_indices.begin()),
+                     [](std::pair<T, size_t>& l) -> int {
+                       return static_cast<int>(l.second);
+                     });
+
+      if (mining_type == MiningType::kHardExample) {
+        for (int m = 0; m < prior_num; ++m) {
+          if (match_indices(n, m) > -1) {
+            if (sel_indices.find(m) == sel_indices.end()) {
+              match_indices_et(n, m) = -1;
+            }
+          } else {
+            if (sel_indices.find(m) != sel_indices.end()) {
+              neg_indices.push_back(m);
+            }
+          }
+        }
+      } else {
+        neg_indices.resize(sel_indices.size());
+        std::copy(sel_indices.begin(), sel_indices.end(), neg_indices.begin());
+      }
+
+      all_neg_indices.push_back(neg_indices);
+      batch_starts.push_back(batch_starts.back() + neg_indices.size());
+    }
+
+    framework::LoD out_neg_indices_lod;
+    out_neg_indices_lod.emplace_back(batch_starts);
+    int neg_offset = 0;
+    auto neg_data = out_neg_indices->mutable_data<int>(
+        framework::make_ddim({static_cast<int>(batch_starts.back()), 1}),
+        ctx.GetPlace());
+
+    for (auto neg_indices : all_neg_indices) {
+      std::copy(neg_indices.begin(), neg_indices.end(), neg_data + neg_offset);
+      neg_offset += neg_indices.size();
+    }
+    out_neg_indices->set_lod(out_neg_indices_lod);
+    return;
+  }
+};
+
+class MineHardExamplesOp : public framework::OperatorWithKernel {
+ public:
+  using framework::OperatorWithKernel::OperatorWithKernel;
+
+ protected:
+  void InferShape(framework::InferShapeContext* ctx) const override {
+    PADDLE_ENFORCE(ctx->HasInput("ClsLoss"),
+                   "Input(ClsLoss) of MineHardExamplesOp should not be null.");
+    PADDLE_ENFORCE(
+        ctx->HasInput("MatchIndices"),
+        "Input(MatchIndices) of MineHardExamplesOp should not be null.");
+    PADDLE_ENFORCE(
+        ctx->HasInput("MatchDist"),
+        "Input(MatchDist) of MineHardExamplesOp should not be null.");
+    PADDLE_ENFORCE(
+        ctx->HasOutput("NegIndices"),
+        "Output(NegIndices) of MineHardExamplesOp should not be null.");
+    PADDLE_ENFORCE(ctx->HasOutput("UpdatedMatchIndices"),
+                   "Output(UpdatedMatchIndices) of MineHardExamplesOp should "
+                   "not be null.");
+
+    auto cls_loss_dims = ctx->GetInputDim("ClsLoss");
+    auto idx_dims = ctx->GetInputDim("MatchIndices");
+    auto dis_dims = ctx->GetInputDim("MatchDist");
+
+    PADDLE_ENFORCE_EQ(cls_loss_dims.size(), 2UL,
+                      "The shape of ClsLoss is [N, Np].");
+    PADDLE_ENFORCE_EQ(idx_dims.size(), 2UL,
+                      "The shape of MatchIndices is [N, Np].");
+    PADDLE_ENFORCE_EQ(dis_dims.size(), 2UL,
+                      "The shape of MatchDist is [N, Np].");
+
+    if (ctx->HasInput("LocLoss")) {
+      auto loc_loss_dims = ctx->GetInputDim("LocLoss");
+      PADDLE_ENFORCE_EQ(loc_loss_dims.size(), 2UL,
+                        "The shape of LocLoss is [N, Np].");
+      PADDLE_ENFORCE_EQ(cls_loss_dims[0], loc_loss_dims[0],
+                        "Batch size of ClsLoss and LocLoss must be the same.");
+      PADDLE_ENFORCE_EQ(
+          cls_loss_dims[1], loc_loss_dims[1],
+          "Prior box number of ClsLoss and LocLoss must be the same.");
+    }
+
+    PADDLE_ENFORCE_EQ(
+        cls_loss_dims[0], idx_dims[0],
+        "Batch size of ClsLoss and MatchIndices must be the same.");
+    PADDLE_ENFORCE_EQ(
+        cls_loss_dims[1], idx_dims[1],
+        "Prior box number of ClsLoss and MatchIndices must be the same.");
+
+    PADDLE_ENFORCE_EQ(cls_loss_dims[0], dis_dims[0],
+                      "Batch size of ClsLoss and MatchDist must be the same.");
+    PADDLE_ENFORCE_EQ(
+        cls_loss_dims[1], idx_dims[1],
+        "Prior box number of ClsLoss and MatchDist must be the same.");
+
+    auto mining_type =
+        GetMiningType(ctx->Attrs().Get<std::string>("mining_type"));
+
+    PADDLE_ENFORCE_NE(mining_type, MiningType::kNone,
+                      "mining_type must be hard_example or max_negative");
+
+    if (mining_type == MiningType::kMaxNegative) {
+      auto neg_pos_ratio = ctx->Attrs().Get<float>("neg_pos_ratio");
+      auto neg_dist_threshold = ctx->Attrs().Get<float>("neg_dist_threshold");
+      PADDLE_ENFORCE_GT(
+          neg_pos_ratio, 0.0f,
+          "neg_pos_ratio must greater than zero in max_negative mode");
+      PADDLE_ENFORCE_GT(
+          neg_dist_threshold, 0.0f,
+          "neg_dist_threshold must greater than zero in max_negative mode");
+    } else if (mining_type == MiningType::kHardExample) {
+      auto sample_size = ctx->Attrs().Get<int>("sample_size");
+      PADDLE_ENFORCE_GT(
+          sample_size, 0,
+          "sample_size must greater than zero in hard_example mode");
+    }
+
+    ctx->SetOutputDim("UpdatedMatchIndices", idx_dims);
+  }
+
+ protected:
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        framework::ToDataType(ctx.Input<framework::Tensor>("ClsLoss")->type()),
+        ctx.device_context());
+  }
+};
+
+class MineHardExamplesOpMaker : public framework::OpProtoAndCheckerMaker {
+ public:
+  MineHardExamplesOpMaker(OpProto* proto, OpAttrChecker* op_checker)
+      : OpProtoAndCheckerMaker(proto, op_checker) {
+    AddInput(
+        "ClsLoss",
+        "(Tensor, default Tensor<float>), The classification loss with shape "
+        "[N, Np], N is the batch size and Np is the number of prior box.");
+    AddInput("LocLoss",
+             "(Tensor, optional, default Tensor<float>), The localization loss "
+             "with shape [N, Np], N is the batch size and Np is the number of "
+             "prior box.")
+        .AsDispensable();
+    AddInput("MatchIndices",
+             "(Tensor, Tensor<int>), Matched indices with shape [N, Np], N is "
+             "the batch size and Np is the number of prior box. "
+             "MatchIndices[i][j] equal -1 means the j-th prior box in i-th "
+             "instance does not match any entity, otherwise means it is "
+             "matched to row.");
+    AddInput("MatchDist",
+             "(Tensor, default Tensor<float>) Matched indices with shape [N, "
+             "Np], N is the batch size and Np is the number of prior box.");
+    AddAttr<float>("neg_pos_ratio",
+                   "(float) The ratio of the negative box to the positive "
+                   "box. Use only when mining_type is max_negative.")
+        .SetDefault(1.0);
+    AddAttr<float>("neg_dist_threshold",
+                   "(float) The negative overlap upper bound for the unmatched "
+                   "predictions. Use only when mining_type is max_negative.")
+        .SetDefault(0.5);
+    AddAttr<int>("sample_size",
+                 "(float) The max sample size of negative box. Use only when "
+                 "mining_type is hard_example.")
+        .SetDefault(0);
+    AddAttr<std::string>("mining_type",
+                         "(float) The mining algorithm name, the value is "
+                         "hard_example or max_negative.")
+        .SetDefault("max_negative")
+        .InEnum({"hard_example", "max_negative"});
+
+    AddOutput(
+        "NegIndices",
+        "(LoDTensor<int>) The output of negative example indices. a LoDTensor "
+        "with shape [Neg, 1]. The size of lod[0] minus 1 is batch size, "
+        "and each element is the prior box index. "
+        "For example, the batch size is 2, the lod is [[0, 1, 2]], "
+        "the sample 0's box 1(MatchIndices[0][1]) is selected, "
+        "and sample 1's box 0 is selected. The output NegIndices is "
+        "[[1], [0]].");
+
+    AddOutput("UpdatedMatchIndices",
+              "(Tensor<int>) The output of updated MatchIndices, a tensor with "
+              "shape [N, Np]. Only update when mining_type is "
+              "hard_example. The input MatchIndices elements will be update to "
+              "-1 when it is not in the candidate high loss list of negative "
+              "examples.");
+
+    AddComment(R"DOC(
+Mine hard examples Operator.
+This operator implements hard example mining to select a subset of negative box indices.
+For each image, selects the box with highest losses. subject to the condition that the 
+box cannot have an Matcht > neg_dist_threshold when mining_type is max_negative. 
+The selected number is min(sample_size, max_negative_box_number) when mining_type is 
+hard_example, or min(neg_pos_ratio * positive_box_number, max_negative_box_number) 
+when mining_type is max_negative, where the max_negative_box_number is the count of 
+MatchIndices elements with value -1.
+)DOC");
+  }
+};
+}  // namespace operators
+}  // namespace paddle
+
+namespace ops = paddle::operators;
+REGISTER_OP_WITHOUT_GRADIENT(mine_hard_examples, ops::MineHardExamplesOp,
+                             ops::MineHardExamplesOpMaker);
+
+REGISTER_OP_CPU_KERNEL(
+    mine_hard_examples,
+    ops::MineHardExamplesKernel<paddle::platform::CPUDeviceContext, float>,
+    ops::MineHardExamplesKernel<paddle::platform::CPUDeviceContext, double>);

python/paddle/v2/fluid/tests/test_mine_hard_examples_op.py

+#   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.
+
+import unittest
+import numpy as np
+import sys
+import math
+from op_test import OpTest
+
+
+class TestMineHardExamplesOp(OpTest):
+    def set_data(self):
+        self.init_test_data()
+        self.inputs = {
+            'ClsLoss': self.cls_loss,
+            'LocLoss': self.loc_loss,
+            'MatchIndices': self.match_indices,
+            'MatchDist': self.match_dis
+        }
+
+        self.attrs = {
+            'neg_pos_ratio': self.neg_pos_ratio,
+            'neg_overlap': self.neg_overlap,
+            'sample_size': self.sample_size,
+            'mining_type': self.mining_type
+        }
+
+        self.outputs = {
+            'NegIndices': (self.neg_indices, self.neg_indices_lod),
+            'UpdatedMatchIndices': self.updated_match_indices
+        }
+
+    def test_check_output(self):
+        self.check_output()
+
+    def test_check_grad(self):
+        return
+
+    def setUp(self):
+        self.op_type = "mine_hard_examples"
+        self.set_data()
+
+    def init_test_data(self):
+        self.neg_pos_ratio = 1.0
+        self.neg_overlap = 0.5
+        self.sample_size = 0
+        self.mining_type = "max_negative"
+        self.cls_loss = np.array([[0.1, 0.1, 0.3],
+                                  [0.3, 0.1, 0.1]]).astype('float32')
+
+        self.loc_loss = np.array([[0.1, 0.2, 0.3],
+                                  [0.3, 0.4, 0.1]]).astype('float32')
+
+        self.match_dis = np.array([[0.2, 0.4, 0.8],
+                                   [0.1, 0.9, 0.3]]).astype('float32')
+
+        self.match_indices = np.array([[0, -1, -1],
+                                       [-1, 0, -1]]).astype('int32')
+
+        self.updated_match_indices = self.match_indices
+
+        self.neg_indices_lod = [[0, 1, 2]]
+        self.neg_indices = np.array([[1], [0]]).astype('int32')
+
+
+class TestMineHardExamplesOpHardExample(TestMineHardExamplesOp):
+    def init_test_data(self):
+        super(TestMineHardExamplesOpHardExample, self).init_test_data()
+        self.mining_type = "hard_example"
+        self.sample_size = 2
+
+        self.cls_loss = np.array([[0.5, 0.1, 0.3],
+                                  [0.3, 0.1, 0.1]]).astype('float32')
+
+        self.loc_loss = np.array([[0.2, 0.2, 0.3],
+                                  [0.3, 0.1, 0.2]]).astype('float32')
+
+        self.match_indices = np.array([[0, -1, -1],
+                                       [-1, 0, -1]]).astype('int32')
+
+        self.updated_match_indices = np.array([[0, -1, -1],
+                                               [-1, -1, -1]]).astype('int32')
+
+        self.neg_indices_lod = [[0, 1, 3]]
+        self.neg_indices = np.array([[2], [0], [2]]).astype('int32')
+
+
+if __name__ == '__main__':
+    unittest.main()