k2pdfopt: optimizes PDFs for viewing on e-readers

[willus]

Originally Posted by JensW

Just wanted to throw in some greetings. Really nice to see that you still find ways to enhance k2pdfopt Willus.
All the best
Jens

Jens--Hello, and thank you! Yes, I am still finding time to tinker with it, much to my wife's chagrin. Drop me a line anytime. You have my e-mail.

[aarora610]

Originally Posted by willus

I appreciate the sentiment. I usually tell people that they should donate the money to some other open source effort or to charity. I am fortunate enough that I don't need it. You have already helped me by giving me a good test case.

The planet needs a lot more people like this. Bless you.

[agelos100]

Hello, Willus,

I have a problem with the conversion with a pdf file. There are both some large gaps at the and of the page, and top and bottom lines half deleted.

I have the latest version of your software, win 7, 32 bit and the following options:

-dev kpw -mode fw -ls-

I enclose sample files before and after conversion.

Thank you in advance.

Angelos

[willus]

Originally Posted by agelos100

I have a problem with the conversion with a pdf file. There are both some large gaps at the and of the page, and top and bottom lines half deleted...

@Angelos -- add this to the "Additional options" box:

-gtr 0.1

That will lower the threshold for breaking lines apart which will allow for better selection of page breaks. The lines in your document are quite close together, plus you are squeezing them into a 3-inch wide screen. That is what is causing the issue. I will look into making this process more robust so it doesn't need such fine tweaking.

[agelos100]

Thank you Willus.

Your suggestion worked like charm!

[danilo93]

Hi! It's me again! I would really like to thank you for all your work! It's amazing! Can you help me to solve this problem: I'm trying to scan one book, but the result that I get is really unsatisfying. See for yourself:

[Image violates guidelines for size - MODERATOR]

As you can see, the picture is not cropped and I have an "empty space" on the left and on the bottom side. I've already tried option "Automatically crop scanned documents" in my scanner's software (in Advanced Document Settings), but the result was not satisfying too. See here:

[Image violates guidelines for size - MODERATOR]

The next thing that I tried was 'Deskewing' the document with Adobe Acrobat Pro, but it didn't work as well. I would really like to know how to solve this problem. I know there's always option to crop page by page in Adobe Acrobat Pro, but this is really huge book and it would take a lot of time and efforts. Then I remembered your "K2pdfopt" software. I knew there was an option of auto-straightening, but it didn't work too... Can you tell me how to solve this problem... Just to know, I don't want to optimize this document for any ebook reader. I just want to optimize IT. Thanks in advance!

Here you can download this problematic pdf:

https://mega.co.nz/#!CEIQQLxQ!9tyO0n...70mvgUg95adEt4

[markom]

Originally Posted by danilo93

Hi! It's me again! I would really like to thank you for all your work! It's amazing! Can you help me to solve this problem: I'm trying to scan one book, but the result that I get is really unsatisfying. See for yourself:

...

You can use Briss or Pdfscissors beforehand (see the first attachment) because it is probably easier for beginners to use its graphic cropping method by fitting a rectangle on the visually overlaid pages (separately for left and right pages if needed) than k2pdfopt's commands.

https://www.mobileread.com/forums/sho...&postcount=704

and then since the text width is about 120 mm i.e. the width of 6" readers in landscape mode you can use k2pdfopt for Kindles 1-5, landscape, native mode, reflow turned off (the second attachment) or without native mode so that you get B&W pdf and smaller file size (the third attachment).

[willus]

Originally Posted by danilo93

Hi! It's me again! I would really like to thank you for all your work! It's amazing! Can you help me to solve this problem: I'm trying to scan one book, but the result that I get is really unsatisfying. See for yourself:

Markom's method of using Briss to crop your PDF before using k2pdfopt is probably the easiest. It can also be done using k2pdfopt's new -cbox option. You can put this in the "Additional Options" box:

-cbox3-o .7,.6,5.6,8.3 -cbox1,2-e 2.3,.5,6,8.5

This crops pages 3 and 5 with one crop box and pages 1, 2, 4, and 6 with another crop box. The other options you then select with k2pdfopt (e.g. -mode fitwidth) will then apply to those cropped regions.

See the -cbox option on my command-line usage page.

[danilo93]

Thank you so much guys!!! This was really helpful. I've tried all 3 programs - Briss, Pdfscissors and K2pdfopt, but does this mean that I need to use different crop tools on each page? As I understood I need to crop page by page and I was wondering if I could crop this document with some software that can do "auto-cropping"... Is there such a thing? Of course, this document is not the whole book. This book contains over 350 pages, so it is really difficult for me to crop each page separately... Is there any way to solve this problem? As I understand, even in K2pdfopt I need to specify all parameters for each page... Am I right?

[quanom]

Hi,

Firstly, I create an optimized PDF file with k2pdfopt. Then, I convert that file to MOBI to use Vocabulary Builder while reading it.

But after conversion, the text in the PDF is not selectable anymore.

Is there a way to overcome this issue?

Thank you.

[willus]

Originally Posted by danilo93

Thank you so much guys!!! This was really helpful. I've tried all 3 programs - Briss, Pdfscissors and K2pdfopt, but does this mean that I need to use different crop tools on each page? As I understood I need to crop page by page and I was wondering if I could crop this document with some software that can do "auto-cropping"... Is there such a thing? Of course, this document is not the whole book. This book contains over 350 pages, so it is really difficult for me to crop each page separately... Is there any way to solve this problem? As I understand, even in K2pdfopt I need to specify all parameters for each page... Am I right?

@Danilo93--Typically k2pdfopt will auto-crop out white spaces around the edges of a document, but because the scanning artifacts (edges of the paper), this will likely not work with your case because of the dark edges. If you can position the book carefully on the scanner so that the odd and even pages are in a consistent position, then my command should still work for the whole book--I figured out one crop box for the even pages (plus the cover page: 1,2e-) and one for the odd pages (3-o).

[willus]

Originally Posted by quanom

Hi,

Firstly, I create an optimized PDF file with k2pdfopt. Then, I convert that file to MOBI to use Vocabulary Builder while reading it.

But after conversion, the text in the PDF is not selectable anymore.

Is there a way to overcome this issue?

Thank you.

@quanom -- Welcome to MR forums. Thank you for posting. The default k2pdfopt conversion should maintain the selectable text in the PDF document if it was selectable to begin with. Can you post a link to the source PDF file you are converting (or a few pages of it, at least)? Or you can send me a private message and I'll tell you how to e-mail it to me so I can investigate.

[danilo93]

Originally Posted by willus

@Danilo93--Typically k2pdfopt will auto-crop out white spaces around the edges of a document, but because the scanning artifacts (edges of the paper), this will likely not work with your case because of the dark edges. If you can position the book carefully on the scanner so that the odd and even pages are in a consistent position, then my command should still work for the whole book--I figured out one crop box for the even pages (plus the cover page: 1,2e-) and one for the odd pages (3-o).

Ok. I'll try to scan whole book in the same way, and then to crop it with tools you gave me... Thank you so muuuch!

[markom]

Originally Posted by danilo93

Thank you so much guys!!! This was really helpful. I've tried all 3 programs - Briss, Pdfscissors and K2pdfopt, but does this mean that I need to use different crop tools on each page? As I understood I need to crop page by page and I was wondering if I could crop this document with some software that can do "auto-cropping"... Is there such a thing? Of course, this document is not the whole book. This book contains over 350 pages, so it is really difficult for me to crop each page separately... Is there any way to solve this problem? As I understand, even in K2pdfopt I need to specify all parameters for each page... Am I right?

No, you can crop the whole book at once, depending whether you have chosen in pdfscissors to show left and right pages stacked together as one pile or separately as two piles so that you adjust one blue rectangle for left-pages stack and then for the right-pages stack.

the same goes for k2pdfopt too, you just copy/paste those commands -cbox3-o .7,.6,5.6,8.3 -cbox1,2-e 2.3,.5,6,8.5 into Additional options box, choose fitwidth mode(under Conversion Mode) and the whole book will be cropped for you at once.


Instructions for Briss:

Start the Briss app by double-clicking its exe file.
Load 801010.pdf file (command under file menu) entering number one (1) at the opened window, for the cover to be excluded from merging (takes about 5-10 seconds for that 801010.pdf file depending on your computer speed).
Draw(adjust) the blue rectangles over those three piles as close to the text as you wish, but there is no need to get too close to the text proper because k2pdfopt will do that later automatically.
You can then preview or just crop the file with commands under Action menu (takes 2-5 seconds for that 801010.pdf file depending on your computer speed).

[danilo93]

@Markom: Thank you so much! I'm going to try this as soon as I scan the whole book!

Originally Posted by willus

Markom's method of using Briss to crop your PDF before using k2pdfopt is probably the easiest. It can also be done using k2pdfopt's new -cbox option. You can put this in the "Additional Options" box:

-cbox3-o .7,.6,5.6,8.3 -cbox1,2-e 2.3,.5,6,8.5

This crops pages 3 and 5 with one crop box and pages 1, 2, 4, and 6 with another crop box. The other options you then select with k2pdfopt (e.g. -mode fitwidth) will then apply to those cropped regions.

See the -cbox option on my command-line usage page.

Hey, Willus! I've just remembered! I'm gonna probably need this tool again... So I wanted to ask you if you could teach me how did you discover this parameters:

-cbox3-o .7,.6,5.6,8.3 -cbox1,2-e 2.3,.5,6,8.5

?

How did you calculated crop boxes, or margins for these 6 pages? Can you teach me how to do it myself? Also, I would like to learn how to write this -cbox command from above. Can you explain it, pls?