plomlompom.com Git - misc/blob - bookmaker.py

   1 #!/usr/bin/env python3
   2 import pypdf
   3 import argparse
   4 import io
   5 from reportlab.lib.pagesizes import A4
   6 a4_width, a4_height = A4
   7
   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 parser.add_argument("-s", "--second", dest="second", help="append second file as input to append")
  17 parser.add_argument("-r", "--rotate", dest="rotate", help="rotate page of number by 90°")
  18 args = parser.parse_args()
  19
  20 with open(args.input_file, 'rb') as file:
  21     reader = pypdf.PdfReader(file)
  22
  23     # determine page range
  24     start_page = 0
  25     end_page = len(reader.pages)
  26     if args.page_range:
  27         start, end = args.page_range.split('-')
  28         if not (len(start) == 0 or start == "start"):
  29             start_page = int(start) - 1
  30         if not (len(end) == 0 or end == "end"):
  31             end_page = int(end)
  32     pages_to_add = []
  33     for page_num in range(start_page, end_page):
  34         page = reader.pages[page_num]
  35         pages_to_add += [page]
  36         print("read in page number", page_num+1)
  37
  38     # add pages of second PDF
  39     if args.second:
  40         file2 = open(args.second, 'rb')
  41         reader2 = pypdf.PdfReader(file2)
  42         page_num = 1
  43         for page in reader2.pages:
  44             pages_to_add += [page]
  45             print("read second PDF's page number", page_num)
  46             page_num += 1
  47
  48     # rotate page canvas
  49     if args.rotate:
  50         page = pages_to_add[int(args.rotate) - 1]
  51         page.add_transformation(pypdf.Transformation().translate(tx=-a4_width/2, ty=-a4_height/2))
  52         page.add_transformation(pypdf.Transformation().rotate(-90))
  53         page.add_transformation(pypdf.Transformation().translate(tx=a4_width/2, ty=a4_height/2))
  54
  55     # normalize all pages to portrait A4
  56     for page in pages_to_add:
  57         if "/Rotate" in page:
  58             page.rotate(360 - page["/Rotate"])
  59         page.mediabox.left = 0
  60         page.mediabox.bottom = 0
  61         page.mediabox.top = a4_height
  62         page.mediabox.right = a4_width
  63         page.cropbox = page.mediabox
  64
  65     # determine page crop
  66     crop_left, crop_bottom, crop_right, crop_top = 0, 0, 0, 0
  67     if args.crop_range:
  68         crop_left, crop_bottom, crop_right, crop_top = [float(x) for x in  args.crop_range.split(',')]
  69     cropped_width  = a4_width - crop_left - crop_right
  70     cropped_height = a4_height - crop_bottom - crop_top
  71     zoom = 1
  72     if args.crop_range:
  73         zoom_horizontal = a4_width / (a4_width - crop_left - crop_right)
  74         zoom_vertical = a4_height / (a4_height - crop_bottom - crop_top)
  75         if (zoom_horizontal > 1 and zoom_vertical < 1) or (zoom_horizontal < 1 and zoom_vertical > 1):
  76             print("Error: opposing zooms.")
  77             exit(1)
  78         elif zoom_horizontal + zoom_vertical > 2:
  79             zoom = min(zoom_horizontal, zoom_vertical)
  80         else:
  81             zoom = max(zoom_horizontal, zoom_vertical)
  82
  83     writer = pypdf.PdfWriter()
  84     if not args.nup4:
  85         odd_page = True
  86         for page in pages_to_add:
  87             if args.symmetry and odd_page:
  88                 page.add_transformation(pypdf.Transformation().translate(tx=-crop_right, ty=-crop_bottom))
  89             else:
  90                 page.add_transformation(pypdf.Transformation().translate(tx=-crop_left, ty=-crop_bottom))
  91             page.add_transformation(pypdf.Transformation().scale(zoom, zoom))
  92             page.mediabox.right = cropped_width * zoom
  93             page.mediabox.top = cropped_height * zoom
  94             writer.add_page(page)
  95             odd_page = not odd_page
  96     else:
  97         n_pages_per_axis = 2
  98         points_per_mm = 2.83465
  99         printable_margin = 4.3 * points_per_mm
 100         printable_scale = (a4_width - 2*printable_margin)/a4_width
 101         spine_limit = 10 * points_per_mm
 102         half_width = a4_width / n_pages_per_axis
 103         half_height = a4_height / n_pages_per_axis
 104         section_scale_factor = 1 / n_pages_per_axis
 105         spine_part_of_page = (spine_limit / half_width) / printable_scale
 106         bonus_shrink_factor = 1 - spine_part_of_page
 107         new_page_order = []
 108         eight_pack = []
 109         mod_to_8 = len(pages_to_add) % 8
 110         if mod_to_8 > 0:
 111             for _ in range(8 - mod_to_8):
 112                 new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
 113                 pages_to_add += [new_page]
 114         i = 0
 115         for page in pages_to_add:
 116             if i == 0:
 117                 eight_pack = []
 118             eight_pack += [page]
 119             i += 1
 120             if i == 8:
 121                 i = 0
 122                 new_page_order += [eight_pack[3]]  # page front, upper left
 123                 new_page_order += [eight_pack[0]]  # page front, upper right
 124                 new_page_order += [eight_pack[7]]  # page front, lower left
 125                 new_page_order += [eight_pack[4]]  # page front, lower right
 126                 new_page_order += [eight_pack[1]]  # page back, upper left
 127                 new_page_order += [eight_pack[2]]  # page back, upper right
 128                 new_page_order += [eight_pack[5]]  # page back, lower left
 129                 new_page_order += [eight_pack[6]]  # page back, lower right
 130         i = 0
 131         page_count = 0
 132         front_page = True
 133         for page in new_page_order:
 134             if i == 0:
 135                 new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
 136
 137             # in-section transformations: align pages on top, left-hand pages to left, right-hand to right
 138             page.add_transformation(pypdf.Transformation().translate(ty=(a4_height / zoom - (a4_height - crop_top))))
 139             if i == 0 or i == 2:
 140                 if args.symmetry:
 141                     page.add_transformation(pypdf.Transformation().translate(tx=-crop_left))
 142                 else:
 143                     page.add_transformation(pypdf.Transformation().translate(tx=-crop_right))
 144             elif i == 1 or i == 3:
 145                 if args.symmetry:
 146                     page.add_transformation(pypdf.Transformation().translate(tx=(a4_width / zoom - (a4_width - crop_left))))
 147                 else:
 148                     page.add_transformation(pypdf.Transformation().translate(tx=(a4_width / zoom - (a4_width - crop_right))))
 149             page.add_transformation(pypdf.Transformation().scale(zoom * bonus_shrink_factor, zoom * bonus_shrink_factor))
 150             if i == 2 or i == 3:
 151                 page.add_transformation(pypdf.Transformation().translate(ty=-2*printable_margin/printable_scale))
 152
 153             # outer section transformations
 154             page.add_transformation(pypdf.Transformation().translate(ty=(1-bonus_shrink_factor)*a4_height))
 155             if i == 0 or i == 1:
 156                 y_section = a4_height
 157                 page.mediabox.bottom = half_height
 158                 page.mediabox.top    = a4_height
 159             if i == 2 or i == 3:
 160                 y_section = 0
 161                 page.mediabox.bottom = 0
 162                 page.mediabox.top  =   half_height
 163             if i == 0 or i == 2:
 164                 x_section = 0
 165                 page.mediabox.left   = 0
 166                 page.mediabox.right  = half_width
 167             if i == 1 or i == 3:
 168                 page.add_transformation(pypdf.Transformation().translate(tx=(1-bonus_shrink_factor)*a4_width))
 169                 x_section = a4_width
 170                 page.mediabox.left   = half_width
 171                 page.mediabox.right  = a4_width
 172             page.add_transformation(pypdf.Transformation().translate(tx=x_section, ty=y_section))
 173             page.add_transformation(pypdf.Transformation().scale(section_scale_factor, section_scale_factor))
 174             new_page.merge_page(page)
 175             page_count += 1
 176             print("merged page number", page_count)
 177             i += 1
 178             if i > 3:
 179                 from reportlab.pdfgen import canvas
 180                 if args.analyze:
 181                     # borders
 182                     packet = io.BytesIO()
 183                     c = canvas.Canvas(packet, pagesize=A4)
 184                     c.setLineWidth(0.1)
 185                     c.line(0, a4_height, a4_width, a4_height)
 186                     c.line(0, half_height, a4_width, half_height)
 187                     c.line(0, 0, a4_width, 0)
 188                     c.line(0, a4_height, 0, 0)
 189                     c.line(half_width, a4_height, half_width, 0)
 190                     c.line(a4_width, a4_height, a4_width, 0)
 191                     c.save()
 192                     new_pdf = pypdf.PdfReader(packet)
 193                     new_page.merge_page(new_pdf.pages[0])
 194                 printable_offset_x = printable_margin
 195                 printable_offset_y = printable_margin * a4_height / a4_width
 196                 new_page.add_transformation(pypdf.Transformation().scale(printable_scale, printable_scale))
 197                 new_page.add_transformation(pypdf.Transformation().translate(tx=printable_offset_x, ty=printable_offset_y))
 198                 x_left_spine_limit = half_width * bonus_shrink_factor
 199                 x_right_spine_limit = a4_width - x_left_spine_limit
 200                 if args.analyze or front_page:
 201                     packet = io.BytesIO()
 202                     c = canvas.Canvas(packet, pagesize=A4)
 203                 if args.analyze:
 204                     # # spine lines
 205                     c.setLineWidth(0.1)
 206                     c.line(x_left_spine_limit, a4_height, x_left_spine_limit, 0)
 207                     c.line(x_right_spine_limit, a4_height, x_right_spine_limit, 0)
 208                 if front_page:
 209                     c.setLineWidth(0.2)
 210                     cut_depth = 19.5 * points_per_mm
 211                     cut_width = 10.5 * points_per_mm
 212                     middle_point_depth = 4 * points_per_mm
 213
 214                     start_up_left_left_x = x_left_spine_limit - 0.5 * cut_width
 215                     start_up_left_right_x = x_left_spine_limit + 0.5 * cut_width
 216                     middle_point_up_left_y = half_height + middle_point_depth
 217                     end_point_up_left_y = half_height + cut_depth
 218                     c.line(start_up_left_right_x, half_height, x_left_spine_limit, end_point_up_left_y)
 219                     c.line(x_left_spine_limit, end_point_up_left_y, x_left_spine_limit, middle_point_up_left_y)
 220                     c.line(x_left_spine_limit, middle_point_up_left_y, start_up_left_left_x, half_height)
 221
 222                     start_down_right_left_x = x_right_spine_limit - 0.5 * cut_width
 223                     start_down_right_right_x = x_right_spine_limit + 0.5 * cut_width
 224                     middle_point_down_right_y = half_height - middle_point_depth
 225                     end_point_down_right_y = half_height - cut_depth
 226                     c.line(start_down_right_left_x, half_height, x_right_spine_limit, end_point_down_right_y)
 227                     c.line(x_right_spine_limit, end_point_down_right_y, x_right_spine_limit, middle_point_down_right_y)
 228                     c.line(x_right_spine_limit, middle_point_down_right_y, start_down_right_right_x, half_height)
 229
 230                 if args.analyze or front_page:
 231                     c.save()
 232                     # packet.seek(0)
 233                     new_pdf = pypdf.PdfReader(packet)
 234                     new_page.merge_page(new_pdf.pages[0])
 235                 writer.add_page(new_page)
 236                 i = 0
 237                 front_page = not front_page
 238
 239     with open(args.output_file, 'wb') as output_file:
 240         writer.write(output_file)
 241     if args.second:
 242         file2.close()