[V1.3] Add the calibration tool code for int8 inference and focus test. (#15062)

* Add the calibration tool code for int8 inference and focus test.

* Fix the calibration tool per the review comments.

test=develop

* Update the calibrator doc and remove extra line.

* Fix the invalid is_negative_input attr set on Mobilenet.

* Add the comments and fix the format issue.

test=develop

* Update the CMakelist.txt for Calibration PR.Disable the Calibration UT if not enable MKLDNN.

test=develop

* Update the CMakeList.txt.

test=develop

* Disable the test_calibration case on WIN and MAC.

test=develop

* Add the missing brackets.

test=develop

* Remove the outdated map operator which not supported on Python3.

test=develop

* Fix the style issue.

test=develop

* 1.Update the CMakeList.txt to disable calibration tool ut when the WITH_MKL is not set;
2.Add the workaround to enable the FLAGS_use_mkldnn for PR_CI(PADDLE).

test=develop

* Fix the typo and format the License header.

test=develop

* 1.Add and Update TODOs per review comments.
2.Code clean.

test=develop

python/paddle/fluid/contrib/int8_inference/__init__.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.

python/paddle/fluid/contrib/tests/CMakeLists.txt

 file(GLOB TEST_OPS RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}" "test_*.py")
 string(REPLACE ".py" "" TEST_OPS "${TEST_OPS}")
 
+if(APPLE OR WIN32 OR NOT WITH_MKL)
+    list(REMOVE_ITEM TEST_OPS test_calibration)
+endif()
+
 foreach(src ${TEST_OPS})
     py_test(${src} SRCS ${src}.py)
 endforeach()

python/paddle/fluid/contrib/tests/test_calibration.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 os
+import numpy as np
+import time
+import sys
+import random
+import paddle
+import paddle.fluid as fluid
+import argparse
+import functools
+import contextlib
+import paddle.fluid.profiler as profiler
+from PIL import Image, ImageEnhance
+import math
+sys.path.append('..')
+import int8_inference.utility as ut
+
+random.seed(0)
+np.random.seed(0)
+
+DATA_DIM = 224
+
+THREAD = 1
+BUF_SIZE = 102400
+
+DATA_DIR = 'data/ILSVRC2012'
+
+img_mean = np.array([0.485, 0.456, 0.406]).reshape((3, 1, 1))
+img_std = np.array([0.229, 0.224, 0.225]).reshape((3, 1, 1))
+
+
+# TODO(guomingz): Remove duplicated code from line 45 ~ line 114
+def resize_short(img, target_size):
+    percent = float(target_size) / min(img.size[0], img.size[1])
+    resized_width = int(round(img.size[0] * percent))
+    resized_height = int(round(img.size[1] * percent))
+    img = img.resize((resized_width, resized_height), Image.LANCZOS)
+    return img
+
+
+def crop_image(img, target_size, center):
+    width, height = img.size
+    size = target_size
+    if center == True:
+        w_start = (width - size) / 2
+        h_start = (height - size) / 2
+    else:
+        w_start = np.random.randint(0, width - size + 1)
+        h_start = np.random.randint(0, height - size + 1)
+    w_end = w_start + size
+    h_end = h_start + size
+    img = img.crop((w_start, h_start, w_end, h_end))
+    return img
+
+
+def process_image(sample, mode, color_jitter, rotate):
+    img_path = sample[0]
+
+    img = Image.open(img_path)
+
+    img = resize_short(img, target_size=256)
+    img = crop_image(img, target_size=DATA_DIM, center=True)
+
+    if img.mode != 'RGB':
+        img = img.convert('RGB')
+
+    img = np.array(img).astype('float32').transpose((2, 0, 1)) / 255
+    img -= img_mean
+    img /= img_std
+
+    return img, sample[1]
+
+
+def _reader_creator(file_list,
+                    mode,
+                    shuffle=False,
+                    color_jitter=False,
+                    rotate=False,
+                    data_dir=DATA_DIR):
+    def reader():
+        with open(file_list) as flist:
+            full_lines = [line.strip() for line in flist]
+            if shuffle:
+                np.random.shuffle(full_lines)
+
+            lines = full_lines
+
+            for line in lines:
+                img_path, label = line.split()
+                img_path = os.path.join(data_dir, img_path)
+                if not os.path.exists(img_path):
+                    continue
+                yield img_path, int(label)
+
+    mapper = functools.partial(
+        process_image, mode=mode, color_jitter=color_jitter, rotate=rotate)
+
+    return paddle.reader.xmap_readers(mapper, reader, THREAD, BUF_SIZE)
+
+
+def val(data_dir=DATA_DIR):
+    file_list = os.path.join(data_dir, 'val_list.txt')
+    return _reader_creator(file_list, 'val', shuffle=False, data_dir=data_dir)
+
+
+class TestCalibration(unittest.TestCase):
+    def setUp(self):
+        # TODO(guomingz): Put the download process in the cmake.
+        # Download and unzip test data set
+        imagenet_dl_url = 'http://paddle-inference-dist.bj.bcebos.com/int8/calibration_test_data.tar.gz'
+        zip_file_name = imagenet_dl_url.split('/')[-1]
+        cmd = 'rm -rf data {}  && mkdir data && wget {} && tar xvf {} -C data'.format(
+            zip_file_name, imagenet_dl_url, zip_file_name)
+        os.system(cmd)
+        # resnet50 fp32 data
+        resnet50_fp32_model_url = 'http://paddle-inference-dist.bj.bcebos.com/int8/resnet50_int8_model.tar.gz'
+        resnet50_zip_name = resnet50_fp32_model_url.split('/')[-1]
+        resnet50_unzip_folder_name = 'resnet50_fp32'
+        cmd = 'rm -rf {} {} && mkdir {} && wget {} && tar xvf {} -C {}'.format(
+            resnet50_unzip_folder_name, resnet50_zip_name,
+            resnet50_unzip_folder_name, resnet50_fp32_model_url,
+            resnet50_zip_name, resnet50_unzip_folder_name)
+        os.system(cmd)
+
+        self.iterations = 100
+        self.skip_batch_num = 5
+
+    def run_program(self, model_path, generate_int8=False, algo='direct'):
+        image_shape = [3, 224, 224]
+        os.environ['FLAGS_use_mkldnn'] = 'True'
+
+        fluid.memory_optimize(fluid.default_main_program())
+
+        exe = fluid.Executor(fluid.CPUPlace())
+
+        [infer_program, feed_dict,
+         fetch_targets] = fluid.io.load_inference_model(model_path, exe)
+
+        t = fluid.transpiler.InferenceTranspiler()
+        t.transpile(infer_program, fluid.CPUPlace())
+
+        val_reader = paddle.batch(val(), batch_size=1)
+
+        if generate_int8:
+            int8_model = os.path.join(os.getcwd(), "calibration_out")
+
+            if os.path.exists(int8_model):
+                os.system("rm -rf " + int8_model)
+                os.system("mkdir " + int8_model)
+
+            print("Start calibration ...")
+
+            calibrator = ut.Calibrator(
+                program=infer_program,
+                pretrained_model=model_path,
+                iterations=100,
+                debug=False,
+                algo=algo)
+
+            sampling_data = {}
+
+            calibrator.generate_sampling_program()
+        test_info = []
+        cnt = 0
+        for batch_id, data in enumerate(val_reader()):
+            image = np.array(
+                [x[0].reshape(image_shape) for x in data]).astype("float32")
+            label = np.array([x[1] for x in data]).astype("int64")
+            label = label.reshape([-1, 1])
+            running_program = calibrator.sampling_program.clone(
+            ) if generate_int8 else infer_program.clone()
+            for op in running_program.current_block().ops:
+                if op.has_attr("use_mkldnn"):
+                    op._set_attr("use_mkldnn", True)
+
+            _, acc1, _ = exe.run(
+                running_program,
+                feed={feed_dict[0]: image,
+                      feed_dict[1]: label},
+                fetch_list=fetch_targets)
+            if generate_int8:
+                for i in calibrator.sampling_program.list_vars():
+                    if i.name in calibrator.sampling_vars:
+                        np_data = np.array(fluid.global_scope().find_var(i.name)
+                                           .get_tensor())
+                        if i.name not in sampling_data:
+                            sampling_data[i.name] = []
+                        sampling_data[i.name].append(np_data)
+
+            test_info.append(np.mean(acc1) * len(data))
+            cnt += len(data)
+
+            if batch_id != self.iterations - 1:
+                continue
+
+            break
+
+        if generate_int8:
+            calibrator.generate_quantized_data(sampling_data)
+            fluid.io.save_inference_model(int8_model, feed_dict, fetch_targets,
+                                          exe, calibrator.sampling_program)
+            print(
+                "Calibration is done and the corresponding files were generated at {}".
+                format(os.path.abspath("calibration_out")))
+        else:
+            return np.sum(test_info) / cnt
+
+    def test_calibration_for_resnet50(self):
+        fp32_acc1 = self.run_program("resnet50_fp32/model")
+        self.run_program("resnet50_fp32/model", True)
+        int8_acc1 = self.run_program("calibration_out")
+        delta_value = np.abs(fp32_acc1 - int8_acc1)
+        self.assertLess(delta_value, 0.01)
+
+
+if __name__ == '__main__':
+    unittest.main()