k2pdfopt: optimizes PDFs for viewing on e-readers

[Fedex15]

Originally Posted by willus

Thanks for the PM. The page breaks are happening because you have a bookmark pointing to almost every page. Add -bp-- to your "additional options" box.

It Worked! Thank you so much!

[isaacbh]

Hello, is there a way to darken the text without affecting the images? Currently I use -g 0.3 which is great for the text but not for the images...

[willus]

Originally Posted by isaacbh

Hello, is there a way to darken the text without affecting the images? Currently I use -g 0.3 which is great for the text but not for the images...

Sorry--there is no present way to treat the image differently from the text with regards to darkening.

[MarjaE]

Is there a way to run k2pdfopt without chopping text up?

Sorry if someone else has already asked this. But I've found k2pdf makes it much harder to select text from some pdfs. Sentences end up out of order, and some words end up impossible to select.

[msh2050]

Originally Posted by willus

I haven't tested that feature in quite a while. It looks like it is not working correctly now. I have logged it as a bug.

any update?

[willus]

Originally Posted by msh2050

any update?

No--sorry. I do not have as much time to update k2pdfopt these days.

[Russell.z]

Hi I have a problem with reflow text where the text is reshaped but the lines are not arranged as they overlap with each other as in the pictures

[willus]

Originally Posted by Russell.z

Hi I have a problem with reflow text where the text is reshaped but the lines are not arranged as they overlap with each other as in the pictures

Can you post or PM to me the source PDF? It is hard to tell what is going on from the posted photos.

[Russell.z]

this is ch 6 pdf
the line is overlap i cant use reflow text
please can you give me setting
can used to convert pdf with large font

[Russell.z]

Originally Posted by willus

Can you post or PM to me the source PDF? It is hard to tell what is going on from the posted photos.

😢☹

[willus]

Originally Posted by Russell.z

this is ch 6 pdf
the line is overlap i cant use reflow text
please can you give me setting
can used to convert pdf with large font

Russell--try the command below (settings also in attached screen shot).

k2pdfopt -as -de 2 -dev kv -col 1 -bpc 1 -vls -3 -vb 1.25 -fc- -mag 2 ch6.pdf

I've attached the result. Some comment about your conversions:
1. I don't think the _k2opt file you posted was converted with the options shown in your previous post. When I tried using your exact same options, I got a very different result. You were clearly using a higher output DPI than 300 or a higher -mag value than 1.
2. Do not use -r for English left-to-right text. It is intended for use with Arabic and other languages that are read from right to left. This is the main reason you were seeing the strange word breaks.
3. I added -as to auto-straighten (de-skew) your text. It was slightly skewed, which makes breaking the lines less reliable.
4. I added -de to try and remove speckles / small artifacts since your scan quality is not very good.
5. You don't need to use -ac (autocrop), at least in the example you sent. It's really more for when you have dark edges at the very edge of your PDF due to poor copying of the original.
6. I removed several options you specified that I felt either weren't necessary or were using the default values anyway.
7. You can adjust the value of the -mag option to change the font size in the output.
8. Not sure you really needed the -vls, -vb, or -bpc options, but I left them in. -bpc 1 will make the output file size smaller if that's what you want--it does 1-bit color resolution. Each pixel can therefore be only black or white--no grayscale. The -vls and -vb options don't really impact this particular conversion.

[polarisrising]

I'm having some trouble converting a pdf and I was hoping I could get some advice. My goal is to turn a pdf with varying 2-column and 1-column text blocks, into a single column .epub. My thought process was to first run the pdf through k2pdfopt to generate the ocr correctly, in a single column, then run it through calibre.

I'm using k2pdfopt in terminal, on Arch Linux and I have Tesseract setup correctly. Here are my arguments:

-m 0.1in,0.8in,0.1in,0.2in -ocr t -ocrhmax .4 -ocrvis t -n- -wrap- -ws -.5 inmemoriarichar00kirk.pdf

Attached is the original pdf and the output that I'm getting.

Basically, the ocr font looks very squished and distorted, and when I run it through calibre, it's treating the work gaps as new <p>.

Thanks!

[willus]

Originally Posted by polarisrising

I'm having some trouble converting a pdf and I was hoping I could get some advice. My goal is to turn a pdf with varying 2-column and 1-column text blocks, into a single column .epub. My thought process was to first run the pdf through k2pdfopt to generate the ocr correctly, in a single column, then run it through calibre.

I'm using k2pdfopt in terminal, on Arch Linux and I have Tesseract setup correctly. Here are my arguments:

-m 0.1in,0.8in,0.1in,0.2in -ocr t -ocrhmax .4 -ocrvis t -n- -wrap- -ws -.5 inmemoriarichar00kirk.pdf

Attached is the original pdf and the output that I'm getting.

Basically, the ocr font looks very squished and distorted, and when I run it through calibre, it's treating the work gaps as new <p>.

You don't need to use Tesseract OCR. Your PDF already has an OCR layer. I'd do something like this:

k2pdfopt -m 0.1in,0.34in,0.05in,0.25in -mode 2col inmemoriamrichar00kirk.pdf

Because the page isn't always in the same place, the -m selection is difficult if you want to crop off the page numbers and horizontal lines. You might add -ehl to erase horizontal lines.

[polarisrising]

Thanks a bunch! Those settings seem to be working, but when I go to import it into Calibre, it's a complete mess. None text is showing up and the pdf is only full of images that are distorted. I figure that's just a Calibre problem, which I'll tinker with, but i wondered if it had to do with how the OCR is being handled.

[willus]

Originally Posted by polarisrising

Thanks a bunch! Those settings seem to be working, but when I go to import it into Calibre, it's a complete mess. None text is showing up and the pdf is only full of images that are distorted. I figure that's just a Calibre problem, which I'll tinker with, but i wondered if it had to do with how the OCR is being handled.

You might try adding -n- to turn off native mode and see if that works any better moving it into calibre. You can try it on just a few pages as a test, e.g. -p 10-20. I suggest this just because when you turn off native mode, k2pdfopt saves the PDF very differently--using bitmaps and its own k2pdfopt-generated OCR layer (extracted from the original OCR layer) rather than just "crop instructions" applied to the original source PDF.