diff options
Diffstat (limited to 'examples/watermark.py')
| -rwxr-xr-x | examples/watermark.py | 123 |
1 files changed, 21 insertions, 102 deletions
diff --git a/examples/watermark.py b/examples/watermark.py index a4d933c..96b686b 100755 --- a/examples/watermark.py +++ b/examples/watermark.py @@ -3,112 +3,31 @@ ''' Simple example of watermarking using form xobjects (pdfrw). -usage: watermark.py my.pdf single_page.pdf +usage: watermark.py [-u] my.pdf single_page.pdf Creates watermark.my.pdf, with every page overlaid with -first page from single_page.pdf +first page from single_page.pdf. If -u is selected, watermark +will be placed underneath page (painted first). + +NB: At one point, this example was extremely complicated, with + multiple options. That only led to errors in implementation, + so it has been re-simplified in order to show basic principles + of the library operation and to match the other examples better. ''' import sys import os -import find_pdfrw -from pdfrw import PdfReader, PdfWriter, PdfDict, PdfName, IndirectPdfDict, PdfArray -from pdfrw.buildxobj import pagexobj - -def fixpage(page, watermark): - - # Find the page's resource dictionary. Create if none - resources = page.inheritable.Resources - if resources is None: - resources = page.Resources = PdfDict() - - # Find or create the parent's xobject dictionary - xobjdict = resources.XObject - if xobjdict is None: - xobjdict = resources.XObject = PdfDict() - - # Allow for an infinite number of cascaded watermarks - index = 0 - while 1: - watermark_name = '/Watermark.%d' % index - if watermark_name not in xobjdict: - break - index += 1 - xobjdict[watermark_name] = watermark - - # Turn the contents into an array if it is not already one - contents = page.Contents - if not isinstance(contents, PdfArray): - contents = page.Contents = PdfArray([contents]) - - # Save initial state before executing page - contents.insert(0, IndirectPdfDict(stream='q\n')) - - # Restore initial state and append the watermark - contents.append(IndirectPdfDict(stream='Q %s Do\n' % watermark_name)) - return page - -def watermark(input_fname, watermark_fname, output_fname=None): - outfn = output_fname or ('watermark.' + os.path.basename(input_fname)) - w = pagexobj(PdfReader(watermark_fname).pages[0]) - pages = PdfReader(input_fname).pages - PdfWriter().addpages([fixpage(x, w) for x in pages]).write(outfn) - return outfn - -def fix_pdf(fname, watermark_fname, indir, outdir): - from os import mkdir, path - if not path.exists(outdir): - mkdir(outdir) - watermark = pagexobj(PdfReader(watermark_fname).pages[0]) - trailer = PdfReader(path.join(indir, fname)) - for page in trailer.pages: - fixpage(page, watermark) - PdfWriter().write(path.join(outdir, fname), trailer) - return len(trailer.pages) - -def batch_watermark(pdfdir, watermark_fname, outputdir='tmp'): - import traceback - from glob import glob - from os import path - fnames=glob(pdfdir+"/*.pdf") - total_pages = 0 - good_files = 0 - - for fname in fnames: - fname = fname.replace(pdfdir+'/','') - try: - total_pages += fix_pdf(fname, watermark_fname, pdfdir, outputdir) - good_files += 1 - print "%s OK" %fname - except Exception: - print "%s Failed miserably" %fname - print traceback.format_exc()[:2000] - #raise - - print "success %.2f%% %s pages" %((float(good_files)/len(fnames))*100, total_pages) - -if __name__ == "__main__": - - from optparse import OptionParser - parser = OptionParser(description = __doc__) - parser.add_option('-i', dest='input_fname', help='file name to be watermarked (pdf)') - parser.add_option('-w', dest='watermark_fname', help='watermark file name (pdf)') - parser.add_option('-d', dest='pdfdir', help='watermark all pdf files in this directory') - parser.add_option('-o', dest='outdir', help='outputdir used with option -d', default='tmp') - options, args = parser.parse_args() - - if options.input_fname and options.watermark_fname: - watermark = pagexobj(PdfReader(options.watermark_fname).pages[0]) - outfn = 'watermark.' + os.path.basename(options.input_fname) - pages = PdfReader(options.input_fname).pages - - PdfWriter().addpages([fixpage(x, watermark) for x in pages]).write(outfn) - - elif options.pdfdir and options.watermark_fname: - batch_watermark(options.pdfdir, options.watermark_fname, options.outdir) - - else: - parser.print_help() - -
\ No newline at end of file +from pdfrw import PdfReader, PdfWriter, PageMerge + +argv = sys.argv[1:] +underneath = '-u' in argv +if underneath: + del argv[argv.index('-u')] +inpfn, wmarkfn = argv +outfn = 'watermark.' + os.path.basename(inpfn) +wmark = PageMerge().add(PdfReader(wmarkfn).pages[0])[0] +trailer = PdfReader(inpfn) +for page in trailer.pages: + PageMerge(page).add(wmark, prepend=underneath).render() +PdfWriter().write(outfn, trailer) |