""" Finds panel order for manga page. >> python .\modules\textdetector\panel_finder.py """ import json import sys from pathlib import Path import cv2 as cv import numpy as np from PIL import Image, ImageDraw, ImageFont from shapely import Polygon from shapely.ops import nearest_points KERNEL_SIZE = 7 BORDER_SIZE = 10 def panel_process_image(img: Image.Image): """Preprocesses an image to make it easier to find panels. Args: img: The image to preprocess. Returns: The preprocessed image. """ img_gray = cv.cvtColor(np.array(img), cv.COLOR_RGB2GRAY) img_gray = cv.GaussianBlur(img_gray, (KERNEL_SIZE, KERNEL_SIZE), 0) img_gray = cv.threshold(img_gray, 200, 255, cv.THRESH_BINARY)[1] # Add black border to image, to help with finding contours img_gray = cv.copyMakeBorder( img_gray, BORDER_SIZE, BORDER_SIZE, BORDER_SIZE, BORDER_SIZE, cv.BORDER_CONSTANT, value=255, ) # Invert image img_gray = cv.bitwise_not(img_gray) return img_gray def remove_contained_contours(polygons): """Removes polygons from a list if any completely contain the other. Args: polygons: A list of polygons. Returns: A list of polygons with any contained polygons removed. """ # Create a new list to store the filtered polygons. filtered_polygons = [] # Iterate over the polygons. for polygon in polygons: # Check if the polygon contains any of the other polygons. contains = False for other_polygon in polygons: # Check if the polygon contains the other polygon and that the polygons if np.array_equal(other_polygon, polygon): continue rect1 = cv.boundingRect(other_polygon) rect2 = cv.boundingRect(polygon) # Check if rect2 is completely within rect1 if ( rect2[0] >= rect1[0] and rect2[1] >= rect1[1] and rect2[0] + rect2[2] <= rect1[0] + rect1[2] and rect2[1] + rect2[3] <= rect1[1] + rect1[3] ): contains = True break # If the polygon does not contain any of the other polygons, add it to the # filtered list. if not contains: filtered_polygons.append(polygon) return filtered_polygons def calc_panel_contours(im: Image.Image): img_gray = panel_process_image(im) contours_raw, hierarchy = cv.findContours( img_gray, cv.RETR_EXTERNAL, cv.CHAIN_APPROX_SIMPLE ) contours = contours_raw min_area = 10000 contours = [i for i in contours if cv.contourArea(i) > min_area] contours = [cv.convexHull(i) for i in contours] contours = remove_contained_contours(contours) # Remap the contours to the original image contours = [i + np.array([[-BORDER_SIZE, -BORDER_SIZE]]) for i in contours] # Sort the contours by their y-coordinate. contours = order_panels(contours, img_gray) return contours def calc_panel_bboxes_xyxy(img: Image.Image): contours = calc_panel_contours(img) panel_bboxes = [cv.boundingRect(c) for c in contours] panel_bboxes_xyxy = [xywh_to_xyxy(i) for i in panel_bboxes] return panel_bboxes_xyxy def draw_contours(im, contours): """Debugging, draws the contours on the image.""" colors = [ (255, 0, 0), (0, 255, 0), (0, 0, 255), ] im_contour = np.array(im) for i, contour in enumerate(range(len(contours))): color = colors[i % len(colors)] im_contour = cv.drawContours(im_contour, contours, i, color, 4, cv.LINE_AA) # Draw a number at the top left of contour x, y, _, _ = cv.boundingRect(contours[i]) cv.putText( im_contour, str(i), (x + 50, y + 50), cv.FONT_HERSHEY_SIMPLEX, 1, color, 2, cv.LINE_AA, ) img = Image.fromarray(im_contour) return img def save_draw_contours(path: Path | str): path = Path(path) pth_out = path.parent / (path.stem + "-contours") if not pth_out.exists(): pth_out.mkdir() # Glob get all images in folder pths = [i for i in path.iterdir() if i.suffix in [".png", ".jpg", ".jpeg"]] for t in pths: print(t) im = Image.open(t) contours = calc_panel_contours(im) img_panels = draw_contours(im, contours) f_name = t.stem + t.suffix img_panels.save(pth_out / f_name) def order_panels(contours, img_gray): """Orders the panels in a comic book page. Args: contours: A list of contours, where each contour is a list of points. Returns: A list of contours, where each contour is a list of points, ordered by their vertical position. """ # Get the bounding boxes for each contour. bounding_boxes = [cv.boundingRect(contour) for contour in contours] # Generate groups of vertically overlapping bounding boxes. groups_indices = generate_vertical_bounding_box_groups_indices(bounding_boxes) c = [] for group in groups_indices: # Reorder contours based on reverse z-order, cs = [bounding_boxes[i] for i in group] order_scores = order_read_direction_scores(cs) # Sort the list based on the location score value combined_list = list(zip(group, order_scores)) sorted_list = sorted(combined_list, key=lambda x: x[1], reverse=True) c.extend(sorted_list) ordered_contours = [contours[i[0]] for i in c] return ordered_contours def order_read_direction_scores(cs): """ Smaller means read first, larger means read last """ order_scores = [1 * (-i[1]) + i[0] * 1 for i in cs] return order_scores def generate_vertical_bounding_box_groups_indices(bounding_boxes): """Generates groups of vertically overlapping bounding boxes. Args: bounding_boxes: A list of bounding boxes, where each bounding box is a tuple of (x, y, width, height). Returns: A list of groups, where each group is a list of bounding boxes that overlap vertically. """ # Operate on indices Sort the bounding boxes by their y-coordinate. bbox_inds = np.argsort([i[1] for i in bounding_boxes]) # generate groups of vertically overlapping bounding boxes groups = [[bbox_inds[0]]] for i in bbox_inds[1:]: is_old_group = False bbox = bounding_boxes[i] start1 = bbox[1] end1 = bbox[1] + bbox[3] for n, group in enumerate(groups): for ind in group: _bbox = bounding_boxes[ind] start2 = _bbox[1] end2 = _bbox[1] + _bbox[3] # Check for any partial overlapping if check_overlap((start1, end1), (start2, end2)): groups[n] = group + [i] is_old_group = True break if is_old_group: break else: groups.append([i]) return groups def check_overlap(range1, range2): # Check if range1 is before range2 if range1[1] < range2[0]: return False # Check if range1 is after range2 elif range1[0] > range2[1]: return False # If neither of the above conditions are met, the ranges must overlap else: return True # Convert xyxy bounding boxes to shapely polygons def polygon_from_xyxy(x, y, x2, y2): return Polygon([(x, y), (x2, y), (x2, y2), (x, y2)]) def closest_text_to_panel_index(text_bboxes_xyxy, panel_bboxes_xyxy): closest_boxes = [] # Iterate over each text bounding box for t_index, text_box in enumerate(text_bboxes_xyxy): # Initialize minimum distance to a large number min_dist = float("inf") # Initialize nearest box # Convert text bounding box to Polygon text_poly = polygon_from_xyxy(*text_box) # Iterate over each panel bounding box p_index = 0 for p_index, panel_box in enumerate(panel_bboxes_xyxy): # Convert panel bounding box to Polygon panel_poly = polygon_from_xyxy(*panel_box) # Find the nearest points between the text and panel bounding boxes nearest_pts = nearest_points(text_poly, panel_poly) # Calculate the distance between the nearest points dist = nearest_pts[0].distance(nearest_pts[1]) # If the distance is less than the minimum distance if dist < min_dist: # Update the minimum distance min_dist = dist # Update the nearest box if not dist: break # Append the nearest box to the list of closest boxes closest_boxes.append((p_index, t_index)) order_indices_dict = {i: [] for i in range(len(panel_bboxes_xyxy))} for order_index in closest_boxes: order_indices_dict[order_index[0]].append(order_index[1]) return order_indices_dict def xywh_to_xyxy(xywh): return [xywh[0], xywh[1], xywh[0] + xywh[2], xywh[1] + xywh[3]] def xyxy_to_xywh(xyxy): return [xyxy[0], xyxy[1], xyxy[2] - xyxy[0], xyxy[3] - xyxy[1]] def reorder_boxes_indices(text_bboxes_xyxy, panel_bboxes_xyxy): panel_text_order = closest_text_to_panel_index(text_bboxes_xyxy, panel_bboxes_xyxy) box_orders = [] for i in range(len(panel_bboxes_xyxy)): text_inds = panel_text_order[i] orders = order_read_direction_scores( [xyxy_to_xywh(i) for i in [text_bboxes_xyxy[i] for i in text_inds]], ) # print(orders) bbox_inds = np.argsort(orders)[::-1] box_orders.extend([text_inds[i] for i in bbox_inds]) return box_orders def draw_bboxes(img, text_bboxes_xyxy, panel_bboxes_xyxy): image_ = img.copy() # Create a drawing object draw = ImageDraw.Draw(image_) # Draw black boxes on the image for i, box in enumerate(text_bboxes_xyxy): # draw.rectangle(xywh_to_xyxy(box), fill="black") draw.rectangle(box, outline="red") draw.text( box[:2], str(i), fill="red", stroke_width=2, font=ImageFont.truetype("arial.ttf", 50), ) for i, box in enumerate(panel_bboxes_xyxy): # draw.rectangle(xywh_to_xyxy(box), fill="black") draw.rectangle(box, outline="blue") draw.text( box[:2], str(i), fill="blue", stroke_width=2, font=ImageFont.truetype("arial.ttf", 50), ) # Show the image return image_ def extract_text_info_from_ballons(data): pages = data["pages"] extracted_data = { k1: [ {k: v for k, v in d.items() if k in ["text", "xyxy", "_bounding_rect"]} for d in pages[k1] ] for k1 in pages.keys() } return extracted_data def text_bboxes_from_ballons(text_info): text_bboxes_xyxy = [i["xyxy"] for i in text_info] return text_bboxes_xyxy def save_panel_text_order(path: Path | str): path = Path(path) path_json = path / (f"imgtrans_{path.stem}" + ".json") pth_out = path.parent / (path.stem + "-panel-text-order") if not pth_out.exists(): pth_out.mkdir() # Glob get all images in folder with open(path_json, encoding="utf8") as f: data = json.load(f) pages = data["pages"] pages_keys = list(pages.keys()) for k in pages_keys: page_info = pages[k] text_bboxes = text_bboxes_from_ballons(page_info) img = Image.open(path / k) panel_bboxes = calc_panel_bboxes_xyxy(img) text_reorderered_index = reorder_boxes_indices(text_bboxes, panel_bboxes) text_bboxes = [text_bboxes[i] for i in text_reorderered_index] img_out = draw_bboxes(img, text_bboxes, panel_bboxes) img_out.save(pth_out / k) def reorder_text_block_data(path: Path | str): path = Path(path) path_json = path / (f"imgtrans_{path.stem}" + ".json") # Glob get all images in folder with open(path_json, encoding="utf8") as f: data = json.load(f) pages = data["pages"] pages_keys = list(pages.keys()) pages_reordered = {} for k in pages_keys: page_info = pages[k] text_bboxes = text_bboxes_from_ballons(page_info) img = Image.open(path / k) panel_bboxes = calc_panel_bboxes_xyxy(img) text_reorderered_index = reorder_boxes_indices(text_bboxes, panel_bboxes) pages_reordered[k] = [page_info[i] for i in text_reorderered_index] data["pages"] = pages_reordered with open(path_json, 'w', encoding="utf8") as f: json.dump(data, f) if __name__ == "__main__": save_draw_contours(sys.argv[1]) save_panel_text_order(sys.argv[1])