Thread: Cropping Pages Permanently with Acrobat Pro
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Old 11-08-2015, 09:57 PM   #20
willus
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Quote:
Originally Posted by PHC View Post
The data doesn't mean anything. An image and its copy can have identical specs but be very different in quality. ...
You are correct. What I discovered doing more experimentation is that if the source PDF has lossless bitmap encodings (e.g. LZW/Flate, as I had in my example), then the ghostscript output with "pdfwrite" is a lossless replica. But if the source PDF has bitmaps with lossy encodings, this is not the case--the ghostscript output will be different. Since k2pdfopt defaults to writing LZW/Flate bitmaps, this method has always worked fine on k2pdfopt output, but it is not as effective for PDFs with lossy encodings. (Also, ghostscript does not support writing PDFs with JBIG2/JPX encodings, which you had in your source PDF, due to patent issues, so it had to change these encodings to something else entirely.)
Last edited by willus; 11-08-2015 at 10:37 PM. Reason: Changed response after more testing.
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