k2pdfopt: optimizes PDFs for viewing on e-readers

[abe1]

Originally Posted by willus

K2pdfopt v2.51 is released.

Thanks for updating.

I have two request (so far) for future release:

#1. Please allow more than 4 presets. A lot more would be nice..



#2. Please add the ability to manually rename or better yet auto-rename rather than overwrite or cancel!


Thanks for writing this lifesaving app.

[abe1]

Originally Posted by willus

See the k2pdfopt FAQ, fourth from last question: "Sometimes I get multiple rows of text at smaller magnification than the rest of the document. Why?" The bottom line is you'll want to put something like:

-gtr 0.1

In the "Additional Options" box. This will encourage k2pdopt to break lines apart more readily. You may have to adjust the number larger or smaller. The default is 0.006. Larger gives more encouragement to break apart the lines.

Thanks for the help stranger. That helped. 0.05 did the trick for me. Also, some other tweaks like changing Smart line break to 0.001 also helped. Here's my final settings if anybody else needs for editing Bangla or other books.

For Text based books
K2PDFOPT_CUSTOM3=Reflow Text;-dev k2 -wrap+ -ppgs -vb -2 -bp m -ocr- -as -col 1 -dr 1.3 -ws -0.001;-bp -fc- -gtr 0.05

For Image based books
K2PDFOPT_CUSTOM4=Reflow Image;-dev k2 -wrap+ -ppgs -vb -2 -bp m -ocr- -as -col 1 -dr 1.3 -ws -0.001;-bp -fc-

[huzo11]

Hello. I am using a linux machine. I tried so many ways to just simply zoom in pages and breaking them into multiple pages. This is how the pages look in my original pdf file.

I am using a Kindle Paperwhite 3 e-reader. I wish to zoom in to the pages and split each page into multiple pages so that the zoomed part fits the width and the screen. I have tried each mode but none of them worked as I intended it to be. Any ideas?

Thanks!

[willus]

Originally Posted by huzo11

Hello. I am using a linux machine. I tried so many ways to just simply zoom in pages and breaking them into multiple pages. This is how the pages look in my original pdf file.

I am using a Kindle Paperwhite 3 e-reader. I wish to zoom in to the pages and split each page into multiple pages so that the zoomed part fits the width and the screen. I have tried each mode but none of them worked as I intended it to be. Any ideas?

Thanks!

The -mode fitwidth option is designed to do what you are asking. How is it not working? Can you post (or PM to me) a link to the source PDF and the converted PDF and why it is not satisfactory? Your source image looks slightly skewed--you may wish to use the -as option to auto-straighten.

[willus]

Originally Posted by abe1

I have two request (so far) for future release:

#1. Please allow more than 4 presets. A lot more would be nice..

#2. Please add the ability to manually rename or better yet auto-rename rather than overwrite or cancel!

I've made a note of your requests.

[willus]

Originally Posted by galm

Hi Willus

For some reason version 2.50 64 bits is not working, tried in win10 64 bits and is not working, it does nothing, also tried in command line with -gui- , again nothing happens. Version 2.50 32 bits works OK, also version 2.42 64 bits works OK.
I redownloaded this time from willus.org(vs willus.com) and reverified the sha-256 checksum, but does not work.

BY the way out of curiosity, what the fast preview option does ? I've done previews with it selected and unselected and couldn't perceive any difference.

Sorry—I did not notice this post until now. Does v2.51a 64-bit work for you? What exact CPU are you using? v2.5x 64-bit may not work with CPUs more than 9-10 years old (e.g. the first Core-i3/i5/i7’s). I have a core-i5 670 that it works on. In the worst case for very old CPUs, the generic version should work. The binaries on willus.org are identical. It’s just a backup site.

The fast preview turns off a document orientation check that k2 does which takes extra time but auto rotates the source document if the text is rotated 90 degrees.

[Loyd]

Hello,

Please what are the best options to convert such PDF (attached) in order to read it in a Kindle PW3 ?
Thank you

[abe1]

#1 Where is the location settings file of K2pdfopt in windows?

#2 Any way to make the conversion process any faster? Only 50% of CPU osage most of the time..

[abe1]

Originally Posted by Loyd

Hello,

Please what are the best options to convert such PDF (attached) in order to read it in a Kindle PW3 ?
Thank you

Try this
M_k2opt.pdf

[Loyd]

Originally Posted by abe1

Try this
Attachment 168929

Thank you !

Please post options used.

[willus]

Originally Posted by Loyd

Thank you !

Please post options used.

Default options (i.e. no special options) seem to work pretty well. Not identical to abe1's conversion, but close.

[willus]

Originally Posted by abe1

#1 Where is the location settings file of K2pdfopt in windows?

#2 Any way to make the conversion process any faster? Only 50% of CPU osage most of the time..

#1. k2pdfopt stores its settings in environment variables.

#2. The only place where I could easily apply parallelization/multithreading was with OCR, which I did (starting with v2.4x). The rest of the operation is very sequentially dependent and therefore difficult to do in parallel. I could have k2pdfopt do chapters of the book in parallel, for example, since they would logically each start on a fresh output page, but I would need to add some kind of library functionality to merge multiple PDF files or internal structures together, which I don't presently have, and I would have to implement some kind of "new chapter" detection mechanism (or force the user to specify the pages). There was a past discussion on this in this thread.

For now: (1) k2pdfopt generates output far faster than it can be read, (2) the user can use the -p option to manually run k2pdfopt in parallel on different sections of a source file and later manually join them, and (3) k2pdfopt is easily batched to run on multiple files overnight. Therefore adding more multithreading is a low priority for me. Of course, k2pdfopt is also open source, so you are welcome to contribute!

[abe1]

Originally Posted by Loyd

Thank you !

Please post options used.

Here You go!



Additional settings:
-bp -fc- -gtr 0.05

Command line:
-wrap+ -ppgs -vb -2 -bp m -ocr- -as -col 1 -odpi 330 -dr 1.3 -ws -0.001

OR

Import from this code

Code:K2PDFOPT_CUSTOM3=KindlPW3;-wrap+ -ppgs -vb -2 -bp m -ocr- -as -col 1 -odpi 330 -dr 1.3 -ws -0.001;-bp -fc- -gtr 0.05

[willus]

Originally Posted by abe1

Command line:
-wrap+ -ppgs -vb -2 -bp m -ocr- -as -col 1 -odpi 330 -dr 1.3 -ws -0.001

A couple of comments on these options:

1. Checking the "Post-process w/Ghostscript" and "Avoid Text Select Overlap" boxes (which result in the -ppgs and -bp m options above, respectively) is really only necessary when native PDF output is selected. Since you also have "Re-flow text" selected, you will not get native PDF output, and these options are of no benefit.

2. The 0.001 value in the "Smart line breaks" numeric entry field (leading to the -ws -0.001 above) is very small for the smart line breaks and would be unlikely to give a good result if actually used (it is only used if the heuristic "smart" algorithm fails to meet a certain decision threshold). I went back and ran your PDF source document from this post through k2pdfopt with both -ws -0.2 and -ws -0.001, and I got an identical result. There was no improvement by using -ws -0.001.

[abe1]

Originally Posted by willus

A couple of comments on these options:

1. Checking the "Post-process w/Ghostscript" and "Avoid Text Select Overlap" boxes (which result in the -ppgs and -bp m options above, respectively) is really only necessary when native PDF output is selected. Since you also have "Re-flow text" selected, you will not get native PDF output, and these options are of no benefit.

2. The 0.001 value in the "Smart line breaks" numeric entry field (leading to the -ws -0.001 above) is very small for the smart line breaks and would be unlikely to give a good result if actually used (it is only used if the heuristic "smart" algorithm fails to meet a certain decision threshold). I went back and ran your PDF source document from this post through k2pdfopt with both -ws -0.2 and -ws -0.001, and I got an identical result. There was no improvement by using -ws -0.001.

I use that settings because that's how converting my bangla books works properly. Check the differance between 0.200 vs 0.001




The other settings are pointless however. I just checked. I don't know which settings does what. Just checked/unchecked settings as I went along till I found a good one. It's not perfect however. But it's good enough.