5 from reportlab.lib.pagesizes import A4
6 a4_width, a4_height = A4
8 parser = argparse.ArgumentParser(description="build print-ready book PDF")
9 parser.add_argument("-i", "--input", dest="input_file", required=True, help="input PDF file")
10 parser.add_argument("-o", "--output", dest="output_file", required=True, help="output PDF file")
11 parser.add_argument("-p", "--pages", dest="page_range", help="page range, e.g., '3-end'")
12 parser.add_argument("-c", "--crop", dest="crop_range", help="crops left, bottom, right, top – e.g., '10,10,10,10'")
13 parser.add_argument("-n", "--nup4", dest="nup4", action='store_true', help="puts 4 input pages onto 1 output page")
14 parser.add_argument("-a", "--analyze", dest="analyze", action="store_true", help="print lines identifying spine, page borders")
15 args = parser.parse_args()
17 with open(args.input_file, 'rb') as file:
18 reader = pypdf.PdfReader(file)
20 # determine page range
22 end_page = len(reader.pages)
24 start, end = args.page_range.split('-')
25 if not (len(start) == 0 or start == "start"):
26 start_page = int(start) - 1
27 if not (len(end) == 0 or end == "end"):
30 for page_num in range(start_page, end_page):
31 page = reader.pages[page_num]
32 pages_to_add += [page]
33 print("read in page number", page_num+1)
35 # normalize all pages to A4
36 for page_num in range(start_page, end_page):
37 page = reader.pages[page_num]
38 page.mediabox.left = 0
39 page.mediabox.bottom = 0
40 page.mediabox.top = a4_height
41 page.mediabox.right = a4_width
42 page.cropbox = page.mediabox
45 crop_left, crop_bottom, crop_right, crop_top = 0, 0, 0, 0
47 crop_left, crop_bottom, crop_right, crop_top = [float(x) for x in args.crop_range.split(',')]
48 cropped_width = a4_width - crop_left - crop_right
49 cropped_height = a4_height - crop_bottom - crop_top
52 zoom_horizontal = a4_width / (a4_width - crop_left - crop_right)
53 zoom_vertical = a4_height / (a4_height - crop_bottom - crop_top)
54 if (zoom_horizontal > 1 and zoom_vertical < 1) or (zoom_horizontal < 1 and zoom_vertical > 1):
55 print("Error: opposing zooms.")
57 elif zoom_horizontal + zoom_vertical > 2:
58 zoom = min(zoom_horizontal, zoom_vertical)
60 zoom = max(zoom_horizontal, zoom_vertical)
62 writer = pypdf.PdfWriter()
64 for page in pages_to_add:
65 page.add_transformation(pypdf.Transformation().translate(tx=-crop_left, ty=-crop_bottom))
66 page.add_transformation(pypdf.Transformation().scale(zoom, zoom))
67 page.mediabox.right = cropped_width * zoom
68 page.mediabox.top = cropped_height * zoom
72 points_per_mm = 2.83465
73 printable_margin = 4.3 * points_per_mm
74 printable_scale = (a4_width - 2*printable_margin)/a4_width
75 spine_limit = 10 * points_per_mm
76 half_width = a4_width / n_pages_per_axis
77 half_height = a4_height / n_pages_per_axis
78 section_scale_factor = 1 / n_pages_per_axis
79 spine_part_of_page = (spine_limit / half_width) / printable_scale
80 bonus_shrink_factor = 1 - spine_part_of_page
83 mod_to_8 = len(pages_to_add) % 8
85 for _ in range(8 - mod_to_8):
86 new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
87 pages_to_add += [new_page]
89 for page in pages_to_add:
96 new_page_order += [eight_pack[3]] # page front, upper left
97 new_page_order += [eight_pack[0]] # page front, upper right
98 new_page_order += [eight_pack[7]] # page front, lower left
99 new_page_order += [eight_pack[4]] # page front, lower right
100 new_page_order += [eight_pack[1]] # page back, upper left
101 new_page_order += [eight_pack[2]] # page back, upper right
102 new_page_order += [eight_pack[5]] # page back, lower left
103 new_page_order += [eight_pack[6]] # page back, lower right
107 for page in new_page_order:
109 new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
111 # in-section transformations: align pages on top, left-hand pages to left, right-hand to right
112 page.add_transformation(pypdf.Transformation().translate(ty=(a4_height / zoom - (a4_height - crop_top))))
114 page.add_transformation(pypdf.Transformation().translate(tx=-crop_left))
115 elif i == 1 or i == 3:
116 page.add_transformation(pypdf.Transformation().translate(tx=(a4_width / zoom - (a4_width - crop_right))))
117 page.add_transformation(pypdf.Transformation().scale(zoom * bonus_shrink_factor, zoom * bonus_shrink_factor))
119 page.add_transformation(pypdf.Transformation().translate(ty=-2*printable_margin/printable_scale))
121 # outer section transformations
122 page.add_transformation(pypdf.Transformation().translate(ty=(1-bonus_shrink_factor)*a4_height))
124 y_section = a4_height
125 page.mediabox.bottom = half_height
126 page.mediabox.top = a4_height
129 page.mediabox.bottom = 0
130 page.mediabox.top = half_height
133 page.mediabox.left = 0
134 page.mediabox.right = half_width
136 page.add_transformation(pypdf.Transformation().translate(tx=(1-bonus_shrink_factor)*a4_width))
138 page.mediabox.left = half_width
139 page.mediabox.right = a4_width
140 page.add_transformation(pypdf.Transformation().translate(tx=x_section, ty=y_section))
141 page.add_transformation(pypdf.Transformation().scale(section_scale_factor, section_scale_factor))
142 new_page.merge_page(page)
144 print("merged page number", page_count)
147 from reportlab.pdfgen import canvas
150 packet = io.BytesIO()
151 c = canvas.Canvas(packet, pagesize=A4)
153 c.line(0, a4_height, a4_width, a4_height)
154 c.line(0, half_height, a4_width, half_height)
155 c.line(0, 0, a4_width, 0)
156 c.line(0, a4_height, 0, 0)
157 c.line(half_width, a4_height, half_width, 0)
158 c.line(a4_width, a4_height, a4_width, 0)
160 new_pdf = pypdf.PdfReader(packet)
161 new_page.merge_page(new_pdf.pages[0])
162 printable_offset_x = printable_margin
163 printable_offset_y = printable_margin * a4_height / a4_width
164 new_page.add_transformation(pypdf.Transformation().scale(printable_scale, printable_scale))
165 new_page.add_transformation(pypdf.Transformation().translate(tx=printable_offset_x, ty=printable_offset_y))
166 x_left_spine_limit = half_width * bonus_shrink_factor
167 x_right_spine_limit = a4_width - x_left_spine_limit
168 if args.analyze or front_page:
169 packet = io.BytesIO()
170 c = canvas.Canvas(packet, pagesize=A4)
174 c.line(x_left_spine_limit, a4_height, x_left_spine_limit, 0)
175 c.line(x_right_spine_limit, a4_height, x_right_spine_limit, 0)
178 cut_depth = 19.5 * points_per_mm
179 cut_width = 10.5 * points_per_mm
180 middle_point_depth = 4 * points_per_mm
182 start_up_left_left_x = x_left_spine_limit - 0.5 * cut_width
183 start_up_left_right_x = x_left_spine_limit + 0.5 * cut_width
184 middle_point_up_left_y = half_height + middle_point_depth
185 end_point_up_left_y = half_height + cut_depth
186 c.line(start_up_left_right_x, half_height, x_left_spine_limit, end_point_up_left_y)
187 c.line(x_left_spine_limit, end_point_up_left_y, x_left_spine_limit, middle_point_up_left_y)
188 c.line(x_left_spine_limit, middle_point_up_left_y, start_up_left_left_x, half_height)
190 start_down_right_left_x = x_right_spine_limit - 0.5 * cut_width
191 start_down_right_right_x = x_right_spine_limit + 0.5 * cut_width
192 middle_point_down_right_y = half_height - middle_point_depth
193 end_point_down_right_y = half_height - cut_depth
194 c.line(start_down_right_left_x, half_height, x_right_spine_limit, end_point_down_right_y)
195 c.line(x_right_spine_limit, end_point_down_right_y, x_right_spine_limit, middle_point_down_right_y)
196 c.line(x_right_spine_limit, middle_point_down_right_y, start_down_right_right_x, half_height)
198 if args.analyze or front_page:
201 new_pdf = pypdf.PdfReader(packet)
202 new_page.merge_page(new_pdf.pages[0])
203 writer.add_page(new_page)
205 front_page = not front_page
207 with open(args.output_file, 'wb') as output_file:
208 writer.write(output_file)