k2pdfopt: optimizes PDFs for viewing on e-readers

[willus]

Originally Posted by kulmam92

Hi Willus,

I'm trying to convert pdf book(not scanned) for the optimal format for kindle voyage. One of the issues that I'm having is that bookmarks information that I can see when I open the original pdf is gone after the conversion. If I open the converted file using adobe reader, bookmarks are missing from the navigation pane.

Below is the option that I used.
-ui- -x -dev kpw -col 1 -f2p -n

Can you help me out?

Bookmarks should work. Can you post or PM me the source PDF file?

[kulmam92]

I sent PM

[willus]

Originally Posted by kulmam92

Hi Willus,

I'm trying to convert pdf book(not scanned) for the optimal format for kindle voyage. One of the issues that I'm having is that bookmarks information that I can see when I open the original pdf is gone after the conversion. If I open the converted file using adobe reader, bookmarks are missing from the navigation pane.

Below is the option that I used.
-ui- -x -dev kpw -col 1 -f2p -n

Can you help me out?

The bookmarks show up fine for me, though I tried it in Windows, and I'm using Sumatra PDF reader to look at the file, not Adobe Reader. I'll send you a sample of my output. What is your OS (and OS version)?

Also, the -f2p option needs a value after it. It is ignored the way you have it. You might want to use this:

-ui- -x -dev kpw -mode fw

I think it will give you the best results for your book provided the text is still large enough to make out on your reader.

[kulmam92]

I checked your file and toc was there. However, when I convert using the same option you provided from my desktop, it's still missing. OS is windows 8.1 enterprise edition. I also tried to convert your sample file but no luck.

I tried to convert using macbook and conversion failed with the below error.
SOURCE PAGE 264 of 494 (8.0 x 9.2 in) ... Segmentation fault: 11

[kulmam92]

I'm posting this to clear out the confusion.
I was using k2pdfoptgui 2.0.exe and it doesn't handle TOC well.
As soon as I use k2pdfopt.exe on windows, everything worked as expected.
Willus thank you for following up this.

[norweger]

Originally Posted by thomass

K2pdfopt optimizes PDF/DJVU files for mobile e-readers (e.g. the Kindle) and smartphones. It works well on multi-column PDF/DJVU files. K2pdfopt is open source.

HOW TO USE K2PDFOPT:
No install is required and no extra files or packages are necessary to run k2pdfopt. Just drag and drop your PDF/DJVU file icon onto the k2pdfopt icon to convert it. You will be prompted for conversion options (as of v1.16). Press <Enter> to convert the file using the default settings. A new PDF file with _k2opt at the end of the name will be created. The output file is optimized for viewing on Kindles and other mobile readers with 6-inch screens (if the settings are not customized). Or drop a folder full of PDF/DJVU files onto the k2pdfopt icon to batch process. You can even drop a folder full of bitmap images to have them converted into a single PDF as if they were pages of a PDF file.


Now it has built-in GUI for Windows version:


k2pdfopt GUI on Linux using Wine: https://www.mobileread.com/forums/sho...17#post2844617

homepage: http://www.willus.com/k2pdfopt/

how to: http://willus.com/archive/k2pdfopt/help/

can be used on Windows, Linux and OS X

Alternative GUIs for k2pdfopt

Do you have a link to the sample file in the OP, before and after? Would like to try both on the cell phone and see/feel the difference.

[agelos100]

Hello Willus,

I am trying to convert a pdf file with k2pdf and I have a minor problem, which you may be able to help.

I attach test.pdf and test_k2opt.pdf files. I have circled the problematic words.

I use re-flow option (which I haven't used much until now) and when a word is divided at the end of a line at the input file, I get quite a big gap when the whole word is repositioned on a single line.

I played with -gtw and -ws option without any success.

I have win7, k2pdf version 2.32 and:
-dev kp2 -de 1.5 -col 1 -odpi 232

Thank you in advance,

Angelos

[willus]

Originally Posted by norweger

Do you have a link to the sample file in the OP, before and after? Would like to try both on the cell phone and see/feel the difference.

Yes--they are both available at http://willus.com/k2pdfopt/ near the top of the page--click on the thumbnail of each file to get the PDF.

[willus]

Originally Posted by agelos100

I use re-flow option (which I haven't used much until now) and when a word is divided at the end of a line at the input file, I get quite a big gap when the whole word is repositioned on a single line.

I played with -gtw and -ws option without any success.

It looks like the hyphen detection algorithm (which has to detect the hyphen purely graphically) needs some tweaking. I will take a look when I get a chance and modify it for the next release if I can improve it.

[Dr. Drib]

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Thanks.

[amiroo]

Hi Willus
I have a kindle paperwhite 2 that you know the same as other readers has problem with A4 pdfs that your valuable software solved it. But kindle paperwhite 2 in comparison with Kindle keyboard has two other problems for SCANNED pdfs.
First it doesn't show some letters of a word in different location of a page. I specifically speak about Persian books but as the are scanned and seen as image I think language is not a matter. By your software this problem solved completely. Thanks

But there is another problem that the quality of a scanned pdf book in Paperwhite is much lower than Kindle keyboard in spite the resolution in Paperwhite is much higher. (212 DPI for Paperwhite and 167 for DPI for keyboard). So it is not a matter of screen resolution. In other words in Kindle Keyboard the edge of fonts are smoother with more quality. (see attached pic and I hope by zooming it you can see the difference)

The k2pdfopt didn't recover this problem (as far as I know and use default options of software and even by increasing resolution) and I suppose maybe this is not the aim of your software and the problem is due to bad software of Kindle Paperwhite!
I think based on your experience maybe you have a remedy or solution for this as I have investigated a lot but no one can give a clear answer even Amazon staffs.
I appreciate any guide on this and again appreciate you for your valuable software.
Cheers

[amiroo]

Hi willus
by help of a guy a good solution found:

Argoniton
Junior Member
Argoniton began at the beginning.

Posts: 1
Karma: 10
Join Date: Jul 2015
Device: Kindle touch 6, Kindle NT 4, ipad, sony xperia s.

Hi everyone I've just solved this problem, merely by using additional option in Acrobat Text Recognition called ClearScan (Tools->Text Recognition-> In this File->Edit-> Clear Scan)

Note: Amazon e-book intentionally reduces quality in scanned pdfs (i.e. images of real pages) beginning from 4 gen, thus you should omit using pictures in pdf. And that acrobat tool successfully deals with.



can you invorporate above step as an option in your software?

cheets

[amiroo]

I checked it on some more pdf file and it seems that the 'clear scan' OCR by Adobe Acrobat only make some of the files better not all of the. Anyway i still wait for the best solution.
Thanks

[willus]

Originally Posted by amiroo

I checked it on some more pdf file and it seems that the 'clear scan' OCR by Adobe Acrobat only make some of the files better not all of the. Anyway i still wait for the best solution.
Thanks

Welcome to MobileRead. It's difficult for me to see a difference in the photo of the two kindles that you posted. Can you do a screen capture from both of them and post those images? And also post the converted PDFs for each kindle? You should be able to google the proper sequence to do a screen capture on each type of kindle. Are you using the paperwhite setting (-dev kpw) so that k2pdfopt saves the images inside the PDF at the exact resolution of the paperwhite? If you can do that, and post the screen capture from the paperwhite, and also the converted PDF file, that would be very helpful.

[amiroo]

Hi Willus
Unfortunately It is not very clear in picture. Please see the two pages of this thread that may clear the matter.
http://www.mobileread.mobi/forums/sh...=215598&page=1
Cheers