comicocr / utils /split_text_region.py
fasdfsa's picture
init
f6f8d06
import cv2, os, re, random
import numpy as np
# import tesserocr
# from tesserocr import PyTessBaseAPI, PSM, OEM
class TextSpan(object):
def __init__(self, top_bnd=None, bottom_bnd=None, left_bnd=None, right_bnd=None):
self.top = top_bnd
self.bottom = bottom_bnd
self.height = self.bottom - self.top if bottom_bnd is not None else None
self.left = left_bnd
self.right = right_bnd
self.width = self.right - self.left if right_bnd is not None else None
def set_top(self, top_bnd):
self.top = top_bnd
return True
def set_bottom(self, bottom_bnd):
if self.top is None or bottom_bnd <= self.top:
return False
self.bottom = bottom_bnd
self.height = self.bottom - self.top
return True
def set_left(self, left_bnd):
self.left = left_bnd
return True
def set_right(self, right_bnd):
if self.left is None or right_bnd <= self.left:
return False
self.right = right_bnd
self.width = right_bnd - self.left
return True
def __getitem__(self, index):
if isinstance(index, int) and index >=0 and index < 4:
return [self.left, self.top, self.right, self.bottom][index]
else:
raise AttributeError(f'Invalid key: {index}')
def split_step0(span, thresh, sumby_yaxis, thresh2=None) -> list[TextSpan]:
candidate_pnts = (np.where(sumby_yaxis[span.top: span.bottom] > thresh)[0] + span.top).tolist()
span_list = []
if len(candidate_pnts) == 0:
return None
stride_tol = 1
span0, span1 = TextSpan(candidate_pnts[0]), TextSpan()
for pnt_ind in range(len(candidate_pnts)-1):
if candidate_pnts[pnt_ind+1] - candidate_pnts[pnt_ind] > stride_tol:
if not span0.set_bottom(candidate_pnts[pnt_ind]):
continue
span_list = split_step1(span0, span_list, thresh=thresh2, sumby_yaxis=sumby_yaxis)
span1.set_top(candidate_pnts[pnt_ind+1])
span0 = span1
span1 = TextSpan()
if len(candidate_pnts)-1 == 0:
if candidate_pnts[0] == candidate_pnts[-1]:
span_list = None
else:
span0 = TextSpan(candidate_pnts[0], candidate_pnts[-1])
span_list = split_step1(span0, span_list, thresh=thresh2, sumby_yaxis=sumby_yaxis)
elif span0.top != candidate_pnts[-1]:
span0.set_bottom(candidate_pnts[-1])
span_list = split_step1(span0, span_list, thresh=thresh2, sumby_yaxis=sumby_yaxis)
return span_list
def split_step1(span, span_list, thresh=None, sumby_yaxis=None):
if thresh is None:
span_list.append(span)
return span_list
else:
subspan_list = split_step0(span, thresh, sumby_yaxis)
# print(np.var(sumby_yaxis[span.top:span.bottom]))
if subspan_list is not None:
_, maxspan = find_span(subspan_list, max)
_, minspan = find_span(subspan_list, min)
sum_height = sum(c.height for c in subspan_list)
if maxspan.height / minspan.height > 2.5 or sum_height / span.height < 0.3 or len(subspan_list) == 1:
subspan_list = None
if subspan_list is not None and len(subspan_list) > 1:
span_list += subspan_list
else:
span_list.append(span)
return span_list
def shrink_span_list(src_img, span_list, shrink_vert_space=True, shrink_hor_space=True):
height, width = src_img.shape[0], src_img.shape[1]
sum_spacing = 0
if shrink_vert_space:
for ii in range(len(span_list)-1):
line_spacing = span_list[ii+1].top - span_list[ii].bottom
sum_spacing += line_spacing
line_spacing = int(round(line_spacing / 2))
span_list[ii+1].top -= line_spacing
span_list[ii].set_bottom(span_list[ii].bottom + line_spacing)
if len(span_list) >= 2:
mean_spacing = int(0.5 * round(sum_spacing / (len(span_list)-1)))
span_list[0].top = max(0, span_list[0].top-mean_spacing)
span_list[0].set_bottom(span_list[0].bottom)
span_list[-1].set_bottom(min(src_img.shape[0], span_list[-1].bottom))
left_var, middle_var = -1, -1
if shrink_hor_space:
left_pnts, middle_pnts = [], []
for ii in range(len(span_list)):
s = span_list[ii]
im = src_img[s.top: s.bottom, 0: width]
sumby_yaxis = np.mean(im, axis=0)
content_array = np.where(sumby_yaxis > 10)[0].tolist()
left, right = 0, width
if len(content_array) != 0:
left, right = content_array[0], content_array[-1]
span_list[ii].set_left(left)
span_list[ii].set_right(right)
s = span_list[ii]
left_pnts.append(left)
middle_pnts.append((left+right)/2)
left_var, middle_var = np.var(np.array(left_pnts)), np.var(np.array(middle_pnts))
return span_list, (left_var, middle_var)
def find_span(span_list, max_or_min=max, key="height"):
if key=="height":
return max_or_min(enumerate(span_list), key=(lambda x: span_list[x[0]].height), default = -1)
else:
return max_or_min(enumerate(span_list), key=(lambda x: span_list[x[0]].width), default = -1)
def discard_spans(span_list, thresh_ratio=0.3):
index, max_span = find_span(span_list, max)
max_height = max_span.height
height_thresh = max_height * thresh_ratio
new_spanlist = []
for sp in span_list:
if sp.height < height_thresh:
continue
new_spanlist.append(sp)
return new_spanlist
def plot_mapresult(sumbyvector, xlength, span_list=None, thresh=None):
'''for experiment'''
try:
import matplotlib.pyplot as plt
plt.plot(sumbyvector)
plt.ylabel('div pnt value')
plt.xlabel('div pnt coord')
s = [0, 255]
x_cords = []
if span_list is not None:
for sp in span_list:
x_cords.append(sp.top)
x_cords.append(sp.bottom)
if thresh is not None:
for tr in thresh:
plt.vlines(x = x_cords, ymin = 0, ymax = max(s),
colors = 'purple',
label = 'vline_multiple - full height')
plt.hlines(y = tr * sumbyvector.mean(), xmin = 0, xmax = xlength, linestyles='--')
plt.show()
except:
pass
def box(width, height):
return np.ones((height, width), dtype=np.uint8)
def crop_img(img, crop_ratio=0.2, clip_width=True, dilate=False):
h, w = img.shape[:2]
moments = cv2.moments(img)
area = moments['m00']
if area != 0:
mean_x = int(round(moments['m10'] / area))
mean_y = int(round(moments['m01'] / area))
crop_r = int(round(crop_ratio * w))
if clip_width:
crop_x0 = np.clip(mean_x - crop_r, 0, w)
crop_x1 = np.clip(mean_x + crop_r, 0, w)
if crop_x1 > crop_x0:
img = img[:, crop_x0: crop_x1]
else:
crop_r = np.clip(crop_r * 2, 0, w - 1)
img = img[:, crop_r:]
img = np.copy(img)
if clip_width and dilate:
w = int(round(w/7))
if w > 1:
img = cv2.dilate(img, box(w, 1), 1)
return img, img.shape[0], img.shape[1]
def split_textblock(src_img, crop_ratio=0.2, blur=False, show_process=False, discard=True, shrink=True, recheck=False, clip_width=True, dilate=True):
if blur:
src_img = cv2.GaussianBlur(src_img,(3,3),cv2.BORDER_DEFAULT)
if crop_ratio > 0:
img, height, width = crop_img(src_img, crop_ratio=crop_ratio, clip_width=clip_width, dilate=dilate)
else:
img, height, width = src_img, src_img.shape[0], src_img.shape[1]
sumby_yaxis = img.mean(axis=1)
bound0 = np.where(sumby_yaxis > sumby_yaxis.mean() * 0.1)[0].tolist()
vars = (-1, -1)
if len(bound0) < 2:
return [TextSpan(0, height-1, 0, width - 1)], vars
base_span = TextSpan(bound0[0], bound0[-1])
meanby_yaxis = sumby_yaxis.mean()
thresh_ratio = [0.4, 0.8]
thresh0 = meanby_yaxis * thresh_ratio[0]
thresh2 = meanby_yaxis * thresh_ratio[1]
span_list = split_step0(base_span, thresh0, sumby_yaxis, thresh2=thresh2)
if span_list is None:
return None, None
if discard:
span_list = discard_spans(span_list)
if shrink:
span_list, vars = shrink_span_list(src_img, span_list)
'''for experiment'''
if show_process:
plot_mapresult(sumby_yaxis, height, span_list=span_list, thresh=thresh_ratio)
if recheck and len(span_list) == 1 and crop_ratio > 0:
return split_textblock(src_img, crop_ratio==-1, show_process=show_process, discard=discard, shrink=shrink, recheck=False)
valid_span_list = []
for span in span_list:
if span.top is None:
span.set_top(0)
if span.left is None:
span.set_left(0)
if span.right is None:
span.set_right(width)
if span.bottom is None:
span.set_bottom(height)
valid_span_list.append(span)
return valid_span_list, vars
# def tessocr_img2text(img, lang):
# img = Image.fromarray(img)
# if re.findall("vert", lang):
# psm = PSM.SINGLE_BLOCK_VERT_TEXT
# else:
# psm = PSM.SINGLE_LINE
# return tesserocr.image_to_text(img, psm=psm, lang=lang, path=TESSDATA_PATH)
# def tessocr_img2text(img, lang):
# psm = "5" if re.findall("vert", lang) else "7"
# config = r'--tessdata-dir "models\tessdata" --psm ' + psm
# return pytesseract.image_to_string(img, lang=lang, config=config)
def textspan2list(span_list):
converted_list = []
for ii, s in enumerate(span_list):
converted_list.append([])
converted_list[ii].append(s.top)
converted_list[ii].append(s.left)
converted_list[ii].append(s.bottom)
converted_list[ii].append(s.right)
return converted_list
def manga_split(img, bbox=None, show_process=False, clip_width=False) -> list[TextSpan]:
im = cv2.rotate(img, cv2.ROTATE_90_CLOCKWISE)
imh, imw = im.shape[:2]
if bbox is None:
bbox = [0, 0, im.shape[1], im.shape[0]]
bboxes = [bbox]
span_list, _ = split_textblock(im, show_process=show_process, shrink=False, recheck=True, discard=False, crop_ratio=0)
if span_list is None:
return [TextSpan(0, 0, im.shape[1], im.shape[0])]
# span_list, _ = shrink_span_list(im, span_list, shrink_vert_space=False)
for ii, span in enumerate(span_list):
left = span.left
right = span.right
if ii == 0:
span.left = 0
else:
span.left = span.top
if ii == len(span_list) - 1:
span.right = im.shape[0]
else:
span.right = span.bottom
span.top = imw - right
span.bottom = imw - left
span.height = span.bottom - span.top
span.width = span.right - span.left
return span_list
def tessocr_img2text_linemode(img, span_list=None, combine_lines=True, show_process=False, gen_data=False, lang="comic6k", jpn_vert=False):
if jpn_vert:
lang = "jpn_vert"
img = cv2.rotate(img, cv2.ROTATE_90_COUNTERCLOCKWISE)
hig = img.shape[0]
wid = img.shape[1]
if hig * wid < 5:
return '', -1, -1
bw = 3
text = ''
alignment, vars = 0, (-1, -1)
if span_list is None:
span_list, vars = split_textblock(img, show_process=show_process)
_, maxspan = find_span(span_list, max)
maxh = bw*2 + maxspan.height
else:
maxh = max([s[2]-s[0] for s in span_list])
maxh = bw*2 + maxh
long_line = []
word_space = int(round(maxh / 8))
img = 255 - img
for ind, s in enumerate(span_list):
if isinstance(s, list):
im = img[s[0]: s[2], s[1]: s[3]]
else:
im = img[s.top: s.bottom, s.left: s.right]
hw1 = int(round((maxh - im.shape[0])/2))
hw2 = maxh - hw1 - im.shape[0]
dst = cv2.copyMakeBorder(im, hw1, hw2, word_space, word_space, cv2.BORDER_CONSTANT, None, value=[255, 255, 255])
if not combine_lines:
text += tessocr_img2text(dst, lang=lang) +'\n'
else:
long_line.append(dst)
if show_process:
cv2.imshow(str(ind), dst)
if combine_lines:
long_line = cv2.hconcat(long_line)
if jpn_vert:
long_line = cv2.rotate(long_line, cv2.ROTATE_90_CLOCKWISE)
if show_process:
cv2.namedWindow("long line:", cv2.WINDOW_NORMAL)
cv2.imshow("long line:", long_line)
if gen_data:
return long_line
res = tessocr_img2text(long_line, lang=lang)
mean_height = -1
if len(span_list) != 0:
if isinstance(span_list[0], list):
mean_height = np.mean(np.array([s[2]-s[0] for s in span_list]))
else:
mean_height = np.mean(np.array([s.height for s in span_list]))
alignment = 1 if vars[1] < vars[0] else 0
return res, mean_height, alignment