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 parser.add_argument("-t", "--symmetry", dest="symmetry", action="store_true", help="alternate horizontal crops between odd and even pages")
16 args = parser.parse_args()
18 with open(args.input_file, 'rb') as file:
19 reader = pypdf.PdfReader(file)
21 # determine page range
23 end_page = len(reader.pages)
25 start, end = args.page_range.split('-')
26 if not (len(start) == 0 or start == "start"):
27 start_page = int(start) - 1
28 if not (len(end) == 0 or end == "end"):
31 for page_num in range(start_page, end_page):
32 page = reader.pages[page_num]
33 pages_to_add += [page]
34 print("read in page number", page_num+1)
36 # normalize all pages to A4
37 for page_num in range(start_page, end_page):
38 page = reader.pages[page_num]
39 page.mediabox.left = 0
40 page.mediabox.bottom = 0
41 page.mediabox.top = a4_height
42 page.mediabox.right = a4_width
43 page.cropbox = page.mediabox
46 crop_left, crop_bottom, crop_right, crop_top = 0, 0, 0, 0
48 crop_left, crop_bottom, crop_right, crop_top = [float(x) for x in args.crop_range.split(',')]
49 cropped_width = a4_width - crop_left - crop_right
50 cropped_height = a4_height - crop_bottom - crop_top
53 zoom_horizontal = a4_width / (a4_width - crop_left - crop_right)
54 zoom_vertical = a4_height / (a4_height - crop_bottom - crop_top)
55 if (zoom_horizontal > 1 and zoom_vertical < 1) or (zoom_horizontal < 1 and zoom_vertical > 1):
56 print("Error: opposing zooms.")
58 elif zoom_horizontal + zoom_vertical > 2:
59 zoom = min(zoom_horizontal, zoom_vertical)
61 zoom = max(zoom_horizontal, zoom_vertical)
63 writer = pypdf.PdfWriter()
66 for page in pages_to_add:
67 if args.symmetry and odd_page:
68 page.add_transformation(pypdf.Transformation().translate(tx=-crop_left, ty=-crop_bottom))
70 page.add_transformation(pypdf.Transformation().translate(tx=-crop_right, ty=-crop_bottom))
71 page.add_transformation(pypdf.Transformation().scale(zoom, zoom))
72 page.mediabox.right = cropped_width * zoom
73 page.mediabox.top = cropped_height * zoom
75 odd_page = not odd_page
78 points_per_mm = 2.83465
79 printable_margin = 4.3 * points_per_mm
80 printable_scale = (a4_width - 2*printable_margin)/a4_width
81 spine_limit = 10 * points_per_mm
82 half_width = a4_width / n_pages_per_axis
83 half_height = a4_height / n_pages_per_axis
84 section_scale_factor = 1 / n_pages_per_axis
85 spine_part_of_page = (spine_limit / half_width) / printable_scale
86 bonus_shrink_factor = 1 - spine_part_of_page
89 mod_to_8 = len(pages_to_add) % 8
91 for _ in range(8 - mod_to_8):
92 new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
93 pages_to_add += [new_page]
95 for page in pages_to_add:
102 new_page_order += [eight_pack[3]] # page front, upper left
103 new_page_order += [eight_pack[0]] # page front, upper right
104 new_page_order += [eight_pack[7]] # page front, lower left
105 new_page_order += [eight_pack[4]] # page front, lower right
106 new_page_order += [eight_pack[1]] # page back, upper left
107 new_page_order += [eight_pack[2]] # page back, upper right
108 new_page_order += [eight_pack[5]] # page back, lower left
109 new_page_order += [eight_pack[6]] # page back, lower right
113 for page in new_page_order:
115 new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
117 # in-section transformations: align pages on top, left-hand pages to left, right-hand to right
118 page.add_transformation(pypdf.Transformation().translate(ty=(a4_height / zoom - (a4_height - crop_top))))
121 page.add_transformation(pypdf.Transformation().translate(tx=-crop_right))
123 page.add_transformation(pypdf.Transformation().translate(tx=-crop_left))
124 elif i == 1 or i == 3:
125 page.add_transformation(pypdf.Transformation().translate(tx=(a4_width / zoom - (a4_width - crop_right))))
126 page.add_transformation(pypdf.Transformation().scale(zoom * bonus_shrink_factor, zoom * bonus_shrink_factor))
128 page.add_transformation(pypdf.Transformation().translate(ty=-2*printable_margin/printable_scale))
130 # outer section transformations
131 page.add_transformation(pypdf.Transformation().translate(ty=(1-bonus_shrink_factor)*a4_height))
133 y_section = a4_height
134 page.mediabox.bottom = half_height
135 page.mediabox.top = a4_height
138 page.mediabox.bottom = 0
139 page.mediabox.top = half_height
142 page.mediabox.left = 0
143 page.mediabox.right = half_width
145 page.add_transformation(pypdf.Transformation().translate(tx=(1-bonus_shrink_factor)*a4_width))
147 page.mediabox.left = half_width
148 page.mediabox.right = a4_width
149 page.add_transformation(pypdf.Transformation().translate(tx=x_section, ty=y_section))
150 page.add_transformation(pypdf.Transformation().scale(section_scale_factor, section_scale_factor))
151 new_page.merge_page(page)
153 print("merged page number", page_count)
156 from reportlab.pdfgen import canvas
159 packet = io.BytesIO()
160 c = canvas.Canvas(packet, pagesize=A4)
162 c.line(0, a4_height, a4_width, a4_height)
163 c.line(0, half_height, a4_width, half_height)
164 c.line(0, 0, a4_width, 0)
165 c.line(0, a4_height, 0, 0)
166 c.line(half_width, a4_height, half_width, 0)
167 c.line(a4_width, a4_height, a4_width, 0)
169 new_pdf = pypdf.PdfReader(packet)
170 new_page.merge_page(new_pdf.pages[0])
171 printable_offset_x = printable_margin
172 printable_offset_y = printable_margin * a4_height / a4_width
173 new_page.add_transformation(pypdf.Transformation().scale(printable_scale, printable_scale))
174 new_page.add_transformation(pypdf.Transformation().translate(tx=printable_offset_x, ty=printable_offset_y))
175 x_left_spine_limit = half_width * bonus_shrink_factor
176 x_right_spine_limit = a4_width - x_left_spine_limit
177 if args.analyze or front_page:
178 packet = io.BytesIO()
179 c = canvas.Canvas(packet, pagesize=A4)
183 c.line(x_left_spine_limit, a4_height, x_left_spine_limit, 0)
184 c.line(x_right_spine_limit, a4_height, x_right_spine_limit, 0)
187 cut_depth = 19.5 * points_per_mm
188 cut_width = 10.5 * points_per_mm
189 middle_point_depth = 4 * points_per_mm
191 start_up_left_left_x = x_left_spine_limit - 0.5 * cut_width
192 start_up_left_right_x = x_left_spine_limit + 0.5 * cut_width
193 middle_point_up_left_y = half_height + middle_point_depth
194 end_point_up_left_y = half_height + cut_depth
195 c.line(start_up_left_right_x, half_height, x_left_spine_limit, end_point_up_left_y)
196 c.line(x_left_spine_limit, end_point_up_left_y, x_left_spine_limit, middle_point_up_left_y)
197 c.line(x_left_spine_limit, middle_point_up_left_y, start_up_left_left_x, half_height)
199 start_down_right_left_x = x_right_spine_limit - 0.5 * cut_width
200 start_down_right_right_x = x_right_spine_limit + 0.5 * cut_width
201 middle_point_down_right_y = half_height - middle_point_depth
202 end_point_down_right_y = half_height - cut_depth
203 c.line(start_down_right_left_x, half_height, x_right_spine_limit, end_point_down_right_y)
204 c.line(x_right_spine_limit, end_point_down_right_y, x_right_spine_limit, middle_point_down_right_y)
205 c.line(x_right_spine_limit, middle_point_down_right_y, start_down_right_right_x, half_height)
207 if args.analyze or front_page:
210 new_pdf = pypdf.PdfReader(packet)
211 new_page.merge_page(new_pdf.pages[0])
212 writer.add_page(new_page)
214 front_page = not front_page
216 with open(args.output_file, 'wb') as output_file:
217 writer.write(output_file)