k2pdfopt: optimizes PDFs for viewing on e-readers

[pdurrant]

Academic papers are often still in copyright. This one even had a copyright notice on each page. Removed. Please be more careful about uploading.

[willus]

Originally Posted by pdurrant

Academic papers are often still in copyright. This one even had a copyright notice on each page. Removed. Please be more careful about uploading.

My attachments replaced with small samples (less than one page of the source document).

[Shohreh]

I find sans serif fonts easier to read on my e-reader.

Unless I missed it, it looks like k2 doesn't support setting the fonts in the output.

Is there a utility that can replace them in the input file?

For instance, here are the fonts in a book I'm currently reading:

.SFNS-Regular_wdth_opsz110000_GRAD_wght (TrueType; embedded)
.SFNS-Regular_wdth_opsz110000_GRAD_wght (TrueType; Roman; embedded)
Alegreya-Regular (TrueType; Roman; embedded)

Thank you.

[Shohreh]

I have another question.

The original PDF is an image-only file — meaning: In SumatraPDF, I can't select text with the mouse.

After running that original file through k2, the output on my e-reader is fine.

However, I'm having a problem with inputs that I ran through Abbyy Fine Reader:
- Saved as "searchable" PDF: The output from k2 inserts carriage returns about half-way through each line
- Saved as "image" PDF: I only get empty pages.

I zipped a sample of each file (original, searchable, image). I used the following commands:

#mt to remove header
#good
k2pdfopt.exe -w 758 -h 1024 -dpi 213 -mode fw -ls- -mt 1.02 -fc- input.original.pdf
#wrong carriage returns
k2pdfopt.exe -w 758 -h 1024 -dpi 213 -mode fw -ls- -mt 1.02 -fc- input.OCR.searchable.pdf
#only empty pages
k2pdfopt.exe -w 758 -h 1024 -dpi 213 -mode fw -ls- -mt 1.02 -fc- input.OCR.image.pdf

Thank you.

[rkomar]

Originally Posted by Shohreh

I find sans serif fonts easier to read on my e-reader.

Unless I missed it, it looks like k2 doesn't support setting the fonts in the output.

Is there a utility that can replace them in the input file?

For instance, here are the fonts in a book I'm currently reading:

.SFNS-Regular_wdth_opsz110000_GRAD_wght (TrueType; embedded)
.SFNS-Regular_wdth_opsz110000_GRAD_wght (TrueType; Roman; embedded)
Alegreya-Regular (TrueType; Roman; embedded)

Thank you.

It is generally a bad idea to replace the fonts in a PDF. When the PDF is constructed, the characters are precisely positioned (i.e. kerned) according to their shapes in the original font. If you change the font, then you get weird spacings between the characters in words (some have bigger gaps, others overlap). It just looks bad.

EPUBs are rendered completely differently from PDFs. There is no kerning information in EPUBs, so swapping fonts doesn't lead to weird character spacing.

[Shohreh]

Too bad. Thanks.

I'm struggling at getting k2 to convert a searchable PDF to something that displays on my reader as well as it does on the computer. For some reason, the output has carriage returns in the middle, along with garbage characters like #, and the font size changes occasionally. Unreadable.

I'm suprised since the doco says that by default, k2 converts PDFs to bitmaps so the output should be clean without having anything fancier to do than this:

k2pdfopt.exe -w 758 -h 1024 input.pdf