NOTES:
+For arguments like -p, page numbers are assumed to start with 1 (not 0, which is treated as an invalid page number value).
+
The target page shape so far is assumed to be A4 in portrait orientation; bookmaker.py normalizes all pages to this format before applying crops, and removes any source PDF /Rotate commands (for their production of landscape orientations).
The --nup4 quartering puts pages into a specific order optimized for no-tumble duplex print-outs that can easily be folded and cut into pages of a small A6 book. Each unit of 8 pages from the source PDF is mapped thus onto two subsequent pages (i.e. front and back of a printed A4 paper):
parser._optionals.title = "OPTIONS"
parser.add_argument("-i", "--input_file", action="append", required=True, help="input PDF file")
parser.add_argument("-o", "--output_file", required=True, help="output PDF file")
-parser.add_argument("-p", "--page_range", action="append", help="page range, e.g., '3-end'")
+parser.add_argument("-p", "--page_range", action="append", help="page range, e.g., '2-9' or '3-end' or 'start-14'")
parser.add_argument("-c", "--crops", action="append", help="cm crops left, bottom, right, top – e.g., '10,10,10,10'; prefix with ':'-delimited page range to limit effect")
parser.add_argument("-r", "--rotate_page", type=int, action="append", help="rotate page of number by 90° (usable multiple times on same page!)")
parser.add_argument("-s", "--symmetry", action="store_true", help="alternate horizontal crops between odd and even pages")
args = parser.parse_args()
# some basic input validation
-for filename in args.input_file:
- if not os.path.isfile(filename):
- raise ValueError("-i: %s is not a file" % filename)
- try:
- with open(filename, 'rb') as file:
- pypdf.PdfReader(file)
- except pypdf.errors.PdfStreamError:
- raise ValueError("-i: cannot interpret %s as PDF file" % filename)
def validate_page_range(p_string, err_msg_prefix):
err_msg = "%s: invalid page range string: %s" % (err_msg_prefix, p_string)
if '-' not in p_string:
- raise ValueError(err_msg)
+ raise ValueError("%s: page range string lacks '-': %s" % (err_msg_prefix, p_string))
tokens = p_string.split("-")
if len(tokens) > 2:
- raise ValueError(err_msg)
+ raise ValueError("%s: page range string has too many '-': %s" % (err_msg_prefix, p_string))
for i, token in enumerate(tokens):
if token == "":
continue
try:
int(token)
except:
- raise ValueError(err_msg)
+ raise ValueError("%s: page range string carries values that are neither integer, nor 'start', nor 'end': %s" % (err_msg_prefix, p_string))
+ if int(token) < 1:
+ raise ValueError("%s: page range string may not carry page numbers <1: %s" % (err_msg_prefix, p_string))
+ start = -1
+ end = -1
+ try:
+ start = int(tokens[0])
+ end = int(tokens[1])
+ except:
+ pass
+ if start > 0 and end > 0 and start > end:
+ raise ValueError("%s: page range starts higher than it ends: %s" % (err_msg_prefix, p_string))
+for filename in args.input_file:
+ if not os.path.isfile(filename):
+ raise ValueError("-i: %s is not a file" % filename)
+ try:
+ with open(filename, 'rb') as file:
+ pypdf.PdfReader(file)
+ except pypdf.errors.PdfStreamError:
+ raise ValueError("-i: cannot interpret %s as PDF file" % filename)
if args.page_range:
for p_string in args.page_range:
validate_page_range(p_string, "-p")
except:
raise ValueError("-c: non-number crop in %s" % c_string)
if args.rotate_page:
- for r in arg.rotate_page:
+ for r in args.rotate_page:
try:
int(r)
except:
raise ValueError("-r: non-integer value: %s" % r)
+ if r < 1:
+ raise ValueError("-r: value must not be <1: %s" % r)
try:
float(args.print_margin)
except:
raise ValueError("-m: non-float value: %s" % arg.print_margin)
-
# select pages from input files
def parse_page_range(range_string, pages):
start_page = 0
if args.page_range and len(args.page_range) > i:
range_string = args.page_range[i]
start_page, end_page = parse_page_range(range_string, reader.pages)
+ if end_page > len(reader.pages): # no need to test start_page cause start_page > end_page is checked above
+ raise ValueError("-p: page range goes beyond pages of input file: %s" % range_string)
for old_page_num in range(start_page, end_page):
new_page_num += 1
page = reader.pages[old_page_num]
pages_to_add += [page]
print("-i, -p: read in %s page number %d as new page %d" % (input_file, old_page_num+1, new_page_num))
-# if necessary, pad pages to multiple of 8
-if args.nup4:
- mod_to_8 = len(pages_to_add) % 8
- if mod_to_8 > 0:
- print("-n: number of input pages %d not multiple of 8, padding to that" % len(pages_to_add))
- for _ in range(8 - mod_to_8):
- new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
- pages_to_add += [new_page]
+# we can do some more input validations now that we know how many pages output should have
+if args.crops:
+ for c_string in args.crops:
+ initial_split = c_string.split(':')
+ if len(initial_split) > 1:
+ start, end = parse_page_range(initial_split[0], pages_to_add)
+ if end > len(pages_to_add):
+ raise ValueError("-c: page range goes beyond number of pages we're building: %s" % initial_split[0])
+if args.rotate_page:
+ for r in args.rotate_page:
+ if r > len(pages_to_add):
+ raise ValueError("-r: page number beyond number of pages we're building: %d" % r)
# rotate page canvas
if args.rotate_page:
page.add_transformation(pypdf.Transformation().translate(tx=a4_width/2, ty=a4_height/2))
print("-r: rotating (by 90°) page", rotate_page)
+# if necessary, pad pages to multiple of 8
+if args.nup4:
+ mod_to_8 = len(pages_to_add) % 8
+ if mod_to_8 > 0:
+ print("-n: number of input pages %d not multiple of 8, padding to that" % len(pages_to_add))
+ for _ in range(8 - mod_to_8):
+ new_page = pypdf.PageObject.create_blank_page(width=a4_width, height=a4_height)
+ pages_to_add += [new_page]
+
# normalize all pages to portrait A4
for page in pages_to_add:
if "/Rotate" in page: