PaddleOCR/ppocr/modeling/heads/det_db_head.py

207 lines
7.4 KiB
Python

#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.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import math
import paddle.fluid as fluid
class DBHead(object):
"""
Differentiable Binarization (DB) for text detection:
see https://arxiv.org/abs/1911.08947
args:
params(dict): super parameters for build DB network
"""
def __init__(self, params):
self.k = params['k']
self.inner_channels = params['inner_channels']
self.C, self.H, self.W = params['image_shape']
print(self.C, self.H, self.W)
def binarize(self, x):
conv1 = fluid.layers.conv2d(
input=x,
num_filters=self.inner_channels // 4,
filter_size=3,
padding=1,
param_attr=fluid.initializer.MSRAInitializer(uniform=False),
bias_attr=False)
conv_bn1 = fluid.layers.batch_norm(
input=conv1,
param_attr=fluid.initializer.ConstantInitializer(value=1.0),
bias_attr=fluid.initializer.ConstantInitializer(value=1e-4),
act="relu")
conv2 = fluid.layers.conv2d_transpose(
input=conv_bn1,
num_filters=self.inner_channels // 4,
filter_size=2,
stride=2,
param_attr=fluid.initializer.MSRAInitializer(uniform=False),
bias_attr=self._get_bias_attr(0.0004, conv_bn1.shape[1], "conv2"),
act=None)
conv_bn2 = fluid.layers.batch_norm(
input=conv2,
param_attr=fluid.initializer.ConstantInitializer(value=1.0),
bias_attr=fluid.initializer.ConstantInitializer(value=1e-4),
act="relu")
conv3 = fluid.layers.conv2d_transpose(
input=conv_bn2,
num_filters=1,
filter_size=2,
stride=2,
param_attr=fluid.initializer.MSRAInitializer(uniform=False),
bias_attr=self._get_bias_attr(0.0004, conv_bn2.shape[1], "conv3"),
act=None)
out = fluid.layers.sigmoid(conv3)
return out
def thresh(self, x):
conv1 = fluid.layers.conv2d(
input=x,
num_filters=self.inner_channels // 4,
filter_size=3,
padding=1,
param_attr=fluid.initializer.MSRAInitializer(uniform=False),
bias_attr=False)
conv_bn1 = fluid.layers.batch_norm(
input=conv1,
param_attr=fluid.initializer.ConstantInitializer(value=1.0),
bias_attr=fluid.initializer.ConstantInitializer(value=1e-4),
act="relu")
conv2 = fluid.layers.conv2d_transpose(
input=conv_bn1,
num_filters=self.inner_channels // 4,
filter_size=2,
stride=2,
param_attr=fluid.initializer.MSRAInitializer(uniform=False),
bias_attr=self._get_bias_attr(0.0004, conv_bn1.shape[1], "conv2"),
act=None)
conv_bn2 = fluid.layers.batch_norm(
input=conv2,
param_attr=fluid.initializer.ConstantInitializer(value=1.0),
bias_attr=fluid.initializer.ConstantInitializer(value=1e-4),
act="relu")
conv3 = fluid.layers.conv2d_transpose(
input=conv_bn2,
num_filters=1,
filter_size=2,
stride=2,
param_attr=fluid.initializer.MSRAInitializer(uniform=False),
bias_attr=self._get_bias_attr(0.0004, conv_bn2.shape[1], "conv3"),
act=None)
out = fluid.layers.sigmoid(conv3)
return out
def _get_bias_attr(self, l2_decay, k, name, gradient_clip=None):
regularizer = fluid.regularizer.L2Decay(l2_decay)
stdv = 1.0 / math.sqrt(k * 1.0)
initializer = fluid.initializer.Uniform(-stdv, stdv)
bias_attr = fluid.ParamAttr(
regularizer=regularizer,
gradient_clip=gradient_clip,
initializer=initializer,
name=name + "_b_attr")
return bias_attr
def step_function(self, x, y):
return fluid.layers.reciprocal(1 + fluid.layers.exp(-self.k * (x - y)))
def __call__(self, conv_features, mode="train"):
c2, c3, c4, c5 = conv_features
param_attr = fluid.initializer.MSRAInitializer(uniform=False)
in5 = fluid.layers.conv2d(
input=c5,
num_filters=self.inner_channels,
filter_size=1,
param_attr=param_attr,
bias_attr=False)
in4 = fluid.layers.conv2d(
input=c4,
num_filters=self.inner_channels,
filter_size=1,
param_attr=param_attr,
bias_attr=False)
in3 = fluid.layers.conv2d(
input=c3,
num_filters=self.inner_channels,
filter_size=1,
param_attr=param_attr,
bias_attr=False)
in2 = fluid.layers.conv2d(
input=c2,
num_filters=self.inner_channels,
filter_size=1,
param_attr=param_attr,
bias_attr=False)
out4 = fluid.layers.elementwise_add(
x=fluid.layers.resize_nearest(
input=in5, scale=2), y=in4) # 1/16
out3 = fluid.layers.elementwise_add(
x=fluid.layers.resize_nearest(
input=out4, scale=2), y=in3) # 1/8
out2 = fluid.layers.elementwise_add(
x=fluid.layers.resize_nearest(
input=out3, scale=2), y=in2) # 1/4
p5 = fluid.layers.conv2d(
input=in5,
num_filters=self.inner_channels // 4,
filter_size=3,
padding=1,
param_attr=param_attr,
bias_attr=False)
p5 = fluid.layers.resize_nearest(input=p5, scale=8)
p4 = fluid.layers.conv2d(
input=out4,
num_filters=self.inner_channels // 4,
filter_size=3,
padding=1,
param_attr=param_attr,
bias_attr=False)
p4 = fluid.layers.resize_nearest(input=p4, scale=4)
p3 = fluid.layers.conv2d(
input=out3,
num_filters=self.inner_channels // 4,
filter_size=3,
padding=1,
param_attr=param_attr,
bias_attr=False)
p3 = fluid.layers.resize_nearest(input=p3, scale=2)
p2 = fluid.layers.conv2d(
input=out2,
num_filters=self.inner_channels // 4,
filter_size=3,
padding=1,
param_attr=param_attr,
bias_attr=False)
fuse = fluid.layers.concat(input=[p5, p4, p3, p2], axis=1)
shrink_maps = self.binarize(fuse)
if mode != "train":
return {"maps": shrink_maps}
threshold_maps = self.thresh(fuse)
binary_maps = self.step_function(shrink_maps, threshold_maps)
y = fluid.layers.concat(
input=[shrink_maps, threshold_maps, binary_maps], axis=1)
predicts = {}
predicts['maps'] = y
return predicts