Quote:
Originally Posted by willus
Below is the output from "pdfinfo" on your PDF file (pdfinfo is in the MuPDF distro). You can see it has a JBIG2 bitmap that is 1 bit-per-pixel in depth (black and white). The compression to get that bitmap down to 22 kB is impressive--30 to 1. Even a 1-bit-depth PNG file compresses to only 96 kB--4 x larger. Clearly JBIG2 compression format for this bitmap is done very well--I'm wondering if it doesn't somehow compress the bitmap for each letter (or common combination of letters) internally and then overlay them? I don't know enough about JBIG2 compression capabilities, but it may well be because the JBIG2 compression used in test1.pdf is doing some "special" tricks that the bug in your paperwhite's firmware has been exposed. I'm guessing there must be other software packages out there that will re-compress images inside a PDF, but I don't know of any that will be able to get to this kind of compression level/quality. Maybe some other folks can chime in? (Or you could start a new thread with the specific question about re-compressing and/or changing decoding of images in a PDF file.)
PDF-1.6
Info object (21 0 R):
<</CreationDate(D:20131209141435+02'00')/Creator(abs)/ModDate(D:20150410155724+03'00')/Producer(K2pdfopt v2.12)/Title<>>>
Pages: 1
Retrieving info from pages 1-1...
Mediaboxes (1):
1 (1 0 R): [ 0 0 223.4717 301.92452 ]
Images (1):
1 (1 0 R): [ JBIG2 ] 1861x2842 1bpc ImageMask (15 0 R)
Form xobjects (1):
1 (1 0 R): Form (13 0 R)
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Hello Willus.
Thank you for your time regarding the problem I have with kindle PW.
I had a chat for second time with Amazon kindle support; they are very friendly but they don't know/understand much about technical issues. They promised to forward the problem to their specialists and they will eventually let me know about it.
With regard to your suggestion to start a new thread, to be honest I do not exactly understand the nature of the problem, I don't know about the structure of pdf files, and for me it would be wrong to start asking details for a problem I cannot comprehend.
If Amazon comes with a follow up email, I will let you know.
Thanks again for your time.
Angelos