PaddleOCR/ppocr/data/imaug/east_process.py

439 lines
17 KiB
Python

#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.
import math
import cv2
import numpy as np
import json
import sys
import os
__all__ = ['EASTProcessTrain']
class EASTProcessTrain(object):
def __init__(self,
image_shape = [512, 512],
background_ratio = 0.125,
min_crop_side_ratio = 0.1,
min_text_size = 10,
**kwargs):
self.input_size = image_shape[1]
self.random_scale = np.array([0.5, 1, 2.0, 3.0])
self.background_ratio = background_ratio
self.min_crop_side_ratio = min_crop_side_ratio
self.min_text_size = min_text_size
def preprocess(self, im):
input_size = self.input_size
im_shape = im.shape
im_size_min = np.min(im_shape[0:2])
im_size_max = np.max(im_shape[0:2])
im_scale = float(input_size) / float(im_size_max)
im = cv2.resize(im, None, None, fx=im_scale, fy=im_scale)
img_mean = [0.485, 0.456, 0.406]
img_std = [0.229, 0.224, 0.225]
# im = im[:, :, ::-1].astype(np.float32)
im = im / 255
im -= img_mean
im /= img_std
new_h, new_w, _ = im.shape
im_padded = np.zeros((input_size, input_size, 3), dtype=np.float32)
im_padded[:new_h, :new_w, :] = im
im_padded = im_padded.transpose((2, 0, 1))
im_padded = im_padded[np.newaxis, :]
return im_padded, im_scale
def rotate_im_poly(self, im, text_polys):
"""
rotate image with 90 / 180 / 270 degre
"""
im_w, im_h = im.shape[1], im.shape[0]
dst_im = im.copy()
dst_polys = []
rand_degree_ratio = np.random.rand()
rand_degree_cnt = 1
if 0.333 < rand_degree_ratio < 0.666:
rand_degree_cnt = 2
elif rand_degree_ratio > 0.666:
rand_degree_cnt = 3
for i in range(rand_degree_cnt):
dst_im = np.rot90(dst_im)
rot_degree = -90 * rand_degree_cnt
rot_angle = rot_degree * math.pi / 180.0
n_poly = text_polys.shape[0]
cx, cy = 0.5 * im_w, 0.5 * im_h
ncx, ncy = 0.5 * dst_im.shape[1], 0.5 * dst_im.shape[0]
for i in range(n_poly):
wordBB = text_polys[i]
poly = []
for j in range(4):
sx, sy = wordBB[j][0], wordBB[j][1]
dx = math.cos(rot_angle) * (sx - cx)\
- math.sin(rot_angle) * (sy - cy) + ncx
dy = math.sin(rot_angle) * (sx - cx)\
+ math.cos(rot_angle) * (sy - cy) + ncy
poly.append([dx, dy])
dst_polys.append(poly)
dst_polys = np.array(dst_polys, dtype=np.float32)
return dst_im, dst_polys
def polygon_area(self, poly):
"""
compute area of a polygon
:param poly:
:return:
"""
edge = [(poly[1][0] - poly[0][0]) * (poly[1][1] + poly[0][1]),
(poly[2][0] - poly[1][0]) * (poly[2][1] + poly[1][1]),
(poly[3][0] - poly[2][0]) * (poly[3][1] + poly[2][1]),
(poly[0][0] - poly[3][0]) * (poly[0][1] + poly[3][1])]
return np.sum(edge) / 2.
def check_and_validate_polys(self, polys, tags, img_height, img_width):
"""
check so that the text poly is in the same direction,
and also filter some invalid polygons
:param polys:
:param tags:
:return:
"""
h, w = img_height, img_width
if polys.shape[0] == 0:
return polys
polys[:, :, 0] = np.clip(polys[:, :, 0], 0, w - 1)
polys[:, :, 1] = np.clip(polys[:, :, 1], 0, h - 1)
validated_polys = []
validated_tags = []
for poly, tag in zip(polys, tags):
p_area = self.polygon_area(poly)
#invalid poly
if abs(p_area) < 1:
continue
if p_area > 0:
#'poly in wrong direction'
if not tag:
tag = True #reversed cases should be ignore
poly = poly[(0, 3, 2, 1), :]
validated_polys.append(poly)
validated_tags.append(tag)
return np.array(validated_polys), np.array(validated_tags)
def draw_img_polys(self, img, polys):
if len(img.shape) == 4:
img = np.squeeze(img, axis=0)
if img.shape[0] == 3:
img = img.transpose((1, 2, 0))
img[:, :, 2] += 123.68
img[:, :, 1] += 116.78
img[:, :, 0] += 103.94
cv2.imwrite("tmp.jpg", img)
img = cv2.imread("tmp.jpg")
for box in polys:
box = box.astype(np.int32).reshape((-1, 1, 2))
cv2.polylines(img, [box], True, color=(255, 255, 0), thickness=2)
import random
ino = random.randint(0, 100)
cv2.imwrite("tmp_%d.jpg" % ino, img)
return
def shrink_poly(self, poly, r):
"""
fit a poly inside the origin poly, maybe bugs here...
used for generate the score map
:param poly: the text poly
:param r: r in the paper
:return: the shrinked poly
"""
# shrink ratio
R = 0.3
# find the longer pair
dist0 = np.linalg.norm(poly[0] - poly[1])
dist1 = np.linalg.norm(poly[2] - poly[3])
dist2 = np.linalg.norm(poly[0] - poly[3])
dist3 = np.linalg.norm(poly[1] - poly[2])
if dist0 + dist1 > dist2 + dist3:
# first move (p0, p1), (p2, p3), then (p0, p3), (p1, p2)
## p0, p1
theta = np.arctan2((poly[1][1] - poly[0][1]),
(poly[1][0] - poly[0][0]))
poly[0][0] += R * r[0] * np.cos(theta)
poly[0][1] += R * r[0] * np.sin(theta)
poly[1][0] -= R * r[1] * np.cos(theta)
poly[1][1] -= R * r[1] * np.sin(theta)
## p2, p3
theta = np.arctan2((poly[2][1] - poly[3][1]),
(poly[2][0] - poly[3][0]))
poly[3][0] += R * r[3] * np.cos(theta)
poly[3][1] += R * r[3] * np.sin(theta)
poly[2][0] -= R * r[2] * np.cos(theta)
poly[2][1] -= R * r[2] * np.sin(theta)
## p0, p3
theta = np.arctan2((poly[3][0] - poly[0][0]),
(poly[3][1] - poly[0][1]))
poly[0][0] += R * r[0] * np.sin(theta)
poly[0][1] += R * r[0] * np.cos(theta)
poly[3][0] -= R * r[3] * np.sin(theta)
poly[3][1] -= R * r[3] * np.cos(theta)
## p1, p2
theta = np.arctan2((poly[2][0] - poly[1][0]),
(poly[2][1] - poly[1][1]))
poly[1][0] += R * r[1] * np.sin(theta)
poly[1][1] += R * r[1] * np.cos(theta)
poly[2][0] -= R * r[2] * np.sin(theta)
poly[2][1] -= R * r[2] * np.cos(theta)
else:
## p0, p3
# print poly
theta = np.arctan2((poly[3][0] - poly[0][0]),
(poly[3][1] - poly[0][1]))
poly[0][0] += R * r[0] * np.sin(theta)
poly[0][1] += R * r[0] * np.cos(theta)
poly[3][0] -= R * r[3] * np.sin(theta)
poly[3][1] -= R * r[3] * np.cos(theta)
## p1, p2
theta = np.arctan2((poly[2][0] - poly[1][0]),
(poly[2][1] - poly[1][1]))
poly[1][0] += R * r[1] * np.sin(theta)
poly[1][1] += R * r[1] * np.cos(theta)
poly[2][0] -= R * r[2] * np.sin(theta)
poly[2][1] -= R * r[2] * np.cos(theta)
## p0, p1
theta = np.arctan2((poly[1][1] - poly[0][1]),
(poly[1][0] - poly[0][0]))
poly[0][0] += R * r[0] * np.cos(theta)
poly[0][1] += R * r[0] * np.sin(theta)
poly[1][0] -= R * r[1] * np.cos(theta)
poly[1][1] -= R * r[1] * np.sin(theta)
## p2, p3
theta = np.arctan2((poly[2][1] - poly[3][1]),
(poly[2][0] - poly[3][0]))
poly[3][0] += R * r[3] * np.cos(theta)
poly[3][1] += R * r[3] * np.sin(theta)
poly[2][0] -= R * r[2] * np.cos(theta)
poly[2][1] -= R * r[2] * np.sin(theta)
return poly
def generate_quad(self, im_size, polys, tags):
"""
Generate quadrangle.
"""
h, w = im_size
poly_mask = np.zeros((h, w), dtype=np.uint8)
score_map = np.zeros((h, w), dtype=np.uint8)
# (x1, y1, ..., x4, y4, short_edge_norm)
geo_map = np.zeros((h, w, 9), dtype=np.float32)
# mask used during traning, to ignore some hard areas
training_mask = np.ones((h, w), dtype=np.uint8)
for poly_idx, poly_tag in enumerate(zip(polys, tags)):
poly = poly_tag[0]
tag = poly_tag[1]
r = [None, None, None, None]
for i in range(4):
dist1 = np.linalg.norm(poly[i] - poly[(i + 1) % 4])
dist2 = np.linalg.norm(poly[i] - poly[(i - 1) % 4])
r[i] = min(dist1, dist2)
# score map
shrinked_poly = self.shrink_poly(
poly.copy(), r).astype(np.int32)[np.newaxis, :, :]
cv2.fillPoly(score_map, shrinked_poly, 1)
cv2.fillPoly(poly_mask, shrinked_poly, poly_idx + 1)
# if the poly is too small, then ignore it during training
poly_h = min(
np.linalg.norm(poly[0] - poly[3]),
np.linalg.norm(poly[1] - poly[2]))
poly_w = min(
np.linalg.norm(poly[0] - poly[1]),
np.linalg.norm(poly[2] - poly[3]))
if min(poly_h, poly_w) < self.min_text_size:
cv2.fillPoly(training_mask,
poly.astype(np.int32)[np.newaxis, :, :], 0)
if tag:
cv2.fillPoly(training_mask,
poly.astype(np.int32)[np.newaxis, :, :], 0)
xy_in_poly = np.argwhere(poly_mask == (poly_idx + 1))
# geo map.
y_in_poly = xy_in_poly[:, 0]
x_in_poly = xy_in_poly[:, 1]
poly[:, 0] = np.minimum(np.maximum(poly[:, 0], 0), w)
poly[:, 1] = np.minimum(np.maximum(poly[:, 1], 0), h)
for pno in range(4):
geo_channel_beg = pno * 2
geo_map[y_in_poly, x_in_poly, geo_channel_beg] =\
x_in_poly - poly[pno, 0]
geo_map[y_in_poly, x_in_poly, geo_channel_beg+1] =\
y_in_poly - poly[pno, 1]
geo_map[y_in_poly, x_in_poly, 8] = \
1.0 / max(min(poly_h, poly_w), 1.0)
return score_map, geo_map, training_mask
def crop_area(self,
im,
polys,
tags,
crop_background=False,
max_tries=50):
"""
make random crop from the input image
:param im:
:param polys:
:param tags:
:param crop_background:
:param max_tries:
:return:
"""
h, w, _ = im.shape
pad_h = h // 10
pad_w = w // 10
h_array = np.zeros((h + pad_h * 2), dtype=np.int32)
w_array = np.zeros((w + pad_w * 2), dtype=np.int32)
for poly in polys:
poly = np.round(poly, decimals=0).astype(np.int32)
minx = np.min(poly[:, 0])
maxx = np.max(poly[:, 0])
w_array[minx + pad_w:maxx + pad_w] = 1
miny = np.min(poly[:, 1])
maxy = np.max(poly[:, 1])
h_array[miny + pad_h:maxy + pad_h] = 1
# ensure the cropped area not across a text
h_axis = np.where(h_array == 0)[0]
w_axis = np.where(w_array == 0)[0]
if len(h_axis) == 0 or len(w_axis) == 0:
return im, polys, tags
for i in range(max_tries):
xx = np.random.choice(w_axis, size=2)
xmin = np.min(xx) - pad_w
xmax = np.max(xx) - pad_w
xmin = np.clip(xmin, 0, w - 1)
xmax = np.clip(xmax, 0, w - 1)
yy = np.random.choice(h_axis, size=2)
ymin = np.min(yy) - pad_h
ymax = np.max(yy) - pad_h
ymin = np.clip(ymin, 0, h - 1)
ymax = np.clip(ymax, 0, h - 1)
if xmax - xmin < self.min_crop_side_ratio * w or \
ymax - ymin < self.min_crop_side_ratio * h:
# area too small
continue
if polys.shape[0] != 0:
poly_axis_in_area = (polys[:, :, 0] >= xmin)\
& (polys[:, :, 0] <= xmax)\
& (polys[:, :, 1] >= ymin)\
& (polys[:, :, 1] <= ymax)
selected_polys = np.where(
np.sum(poly_axis_in_area, axis=1) == 4)[0]
else:
selected_polys = []
if len(selected_polys) == 0:
# no text in this area
if crop_background:
im = im[ymin:ymax + 1, xmin:xmax + 1, :]
polys = []
tags = []
return im, polys, tags
else:
continue
im = im[ymin:ymax + 1, xmin:xmax + 1, :]
polys = polys[selected_polys]
tags = tags[selected_polys]
polys[:, :, 0] -= xmin
polys[:, :, 1] -= ymin
return im, polys, tags
return im, polys, tags
def crop_background_infor(self, im, text_polys, text_tags):
im, text_polys, text_tags = self.crop_area(
im, text_polys, text_tags, crop_background=True)
if len(text_polys) > 0:
return None
# pad and resize image
input_size = self.input_size
im, ratio = self.preprocess(im)
score_map = np.zeros((input_size, input_size), dtype=np.float32)
geo_map = np.zeros((input_size, input_size, 9), dtype=np.float32)
training_mask = np.ones((input_size, input_size), dtype=np.float32)
return im, score_map, geo_map, training_mask
def crop_foreground_infor(self, im, text_polys, text_tags):
im, text_polys, text_tags = self.crop_area(
im, text_polys, text_tags, crop_background=False)
if text_polys.shape[0] == 0:
return None
#continue for all ignore case
if np.sum((text_tags * 1.0)) >= text_tags.size:
return None
# pad and resize image
input_size = self.input_size
im, ratio = self.preprocess(im)
text_polys[:, :, 0] *= ratio
text_polys[:, :, 1] *= ratio
_, _, new_h, new_w = im.shape
# print(im.shape)
# self.draw_img_polys(im, text_polys)
score_map, geo_map, training_mask = self.generate_quad(
(new_h, new_w), text_polys, text_tags)
return im, score_map, geo_map, training_mask
def __call__(self, data):
im = data['image']
text_polys = data['polys']
text_tags = data['ignore_tags']
if im is None:
return None
if text_polys.shape[0] == 0:
return None
#add rotate cases
if np.random.rand() < 0.5:
im, text_polys = self.rotate_im_poly(im, text_polys)
h, w, _ = im.shape
text_polys, text_tags = self.check_and_validate_polys(text_polys,
text_tags, h, w)
if text_polys.shape[0] == 0:
return None
# random scale this image
rd_scale = np.random.choice(self.random_scale)
im = cv2.resize(im, dsize=None, fx=rd_scale, fy=rd_scale)
text_polys *= rd_scale
if np.random.rand() < self.background_ratio:
outs = self.crop_background_infor(im, text_polys, text_tags)
else:
outs = self.crop_foreground_infor(im, text_polys, text_tags)
if outs is None:
return None
im, score_map, geo_map, training_mask = outs
score_map = score_map[np.newaxis, ::4, ::4].astype(np.float32)
geo_map = np.swapaxes(geo_map, 1, 2)
geo_map = np.swapaxes(geo_map, 1, 0)
geo_map = geo_map[:, ::4, ::4].astype(np.float32)
training_mask = training_mask[np.newaxis, ::4, ::4]
training_mask = training_mask.astype(np.float32)
data['image'] = im[0]
data['score_map'] = score_map
data['geo_map'] = geo_map
data['training_mask'] = training_mask
# print(im.shape, score_map.shape, geo_map.shape, training_mask.shape)
return data