123 lines
4.4 KiB
Python

from itertools import count
import cv2
import numpy as np
import pdf2image
from matplotlib import pyplot as plt
from timeit import timeit
def parse(image: np.array):
gray_scale = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
th1, img_bin = cv2.threshold(gray_scale, 200, 255, cv2.THRESH_BINARY)
img_bin = ~img_bin
line_min_width = 5
kernel_h = np.ones((1, line_min_width), np.uint8)
kernel_v = np.ones((line_min_width, 1), np.uint8)
img_bin_h = cv2.morphologyEx(img_bin, cv2.MORPH_OPEN, kernel_h)
img_bin_v = cv2.morphologyEx(img_bin, cv2.MORPH_OPEN, kernel_v)
# print([cv2.countNonZero(row) for row in img_bin_v])
img_bin_final = img_bin_h | img_bin_v
find_and_close_edges(img_bin_final)
_, labels, stats, _ = cv2.connectedComponentsWithStats(~img_bin_final, connectivity=8, ltype=cv2.CV_32S)
return labels, stats
# def filter_unconnected_cells(stats):
# filtered_cells = []
# for left, middle, right in zip(stats[0:], stats[1:], list(stats[2:])+[None]):
# x, y, w, h, area = middle
# if w > 35 and h > 13 and area > 500:
# if y == left[1] or y == right[1]:
# filtered_cells.append(middle)
# return filtered_cells
def filter_unconnected_cells(stats):
filtered_cells = []
# print(stats)
for left, middle, right in zip(stats[0:], stats[1:], list(stats[2:]) + [np.array([None, None, None, None, None])]):
x, y, w, h, area = middle
if w > 35 and h > 13 and area > 500:
if right[1] is None:
if y == left[1] or x == left[0]:
filtered_cells.append(middle)
else:
if y == left[1] or y == right[1] or x == left[0] or x == right[0]:
filtered_cells.append(middle)
return filtered_cells
# def annotate_image(image, stats):
# stats = filter_unconnected_cells(stats)
# for i,val in enumerate(stats):
# x, y, w, h, area = stats[i][0], stats[i][1], stats[i][2], stats[i][3], stats[i][4]
# cv2.rectangle(image, (x, y), (x + w, y + h), (255, 0, 255), 2)
#
# for i, (s, v) in enumerate(zip(["x", "y", "w", "h"], [x, y, w, h])):
# anno = f"{s} = {v}"
# xann = int(x + 5)
# yann = int(y + h - (20 * (i + 1)))
# cv2.putText(image, anno, (xann, yann), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (255, 0, 255), 2)
#
# return image
def annotate_image(image, stats):
stats = filter_unconnected_cells(stats)
for stat in stats:
x, y, w, h, area = stat
cv2.rectangle(image, (x, y), (x + w, y + h), (255, 0, 255), 2)
for i, (s, v) in enumerate(zip(["x", "y", "w", "h"], [x, y, w, h])):
anno = f"{s} = {v}"
xann = int(x + 5)
yann = int(y + h - (20 * (i + 1)))
cv2.putText(image, anno, (xann, yann), cv2.FONT_HERSHEY_SIMPLEX, 0.7, (255, 0, 255), 2)
return image
def find_and_close_edges(img_bin_final):
contours, hierarchy = cv2.findContours(img_bin_final, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
for cnt in contours:
missing_external_edges = True
left = tuple(cnt[cnt[:, :, 0].argmin()][0])
right = tuple(cnt[cnt[:, :, 0].argmax()][0])
top = tuple(cnt[cnt[:, :, 1].argmin()][0])
bottom = tuple(cnt[cnt[:, :, 1].argmax()][0])
topleft = [left[0] + 1, top[1]]
# print(cnt, left, top, topleft)
bottomright = [right[0] - 1, bottom[1]]
for arr in cnt:
if np.array_equal(arr, np.array([bottomright])) or np.array_equal(arr, np.array([topleft])):
missing_external_edges = False
break
if missing_external_edges and (bottomright[0]-topleft[0])*(bottomright[1]-topleft[1])>= 50000:
topleft[0] -= 1
bottomright[0] += 1
cv2.rectangle(img_bin_final, tuple(topleft), tuple(bottomright), (255,255,255) , 2)
print("missing cell detectet rectangle drawn")
return img_bin_final
def parse_tables_in_pdf(pages):
return zip(map(parse, pages), count())
def annotate_tables_in_pdf(pdf_path, page_index=1):
timeit()
page = pdf2image.convert_from_path(pdf_path, first_page=page_index + 1, last_page=page_index + 1)[0]
page = np.array(page)
_, stats = parse(page)
page = annotate_image(page, stats)
print(timeit())
fig, ax = plt.subplots(1, 1)
fig.set_size_inches(20, 20)
ax.imshow(page)
plt.show()