Formatting scanned document PDF’s for Kobo Glo eReader¶
If, like me, you want to reformat some scanned documents so you can read them on the Kobo Glo eReader, you will find a pain of aliasing and Morié patterns.
I finally spent an afternoon constructing artificial TIFF files to get to the bottom of why it gave me aliasing no matter what I did.
It transpired that there is a one-off bug in the Kobo PDF viewer, but it is easy to circumvemt it.
In landscape mode, the first page must have the dimensions 941x751 and all subsequent pages must be 942x751.
The first page will get aliasing errors, but all the rest will not.
To assemble a pile of TIFF files, I use:
tiffcp input*.tif tmp.tif
tiff2pdf -n -f -F -z tmp.tif > output.pdf
Device details:¶
Kobo Glo, Software 3.3.0 (8eb9c1f8b2) 4/17/14
Formatting scanned document PDF’s for Kobo Aura H2O eReader¶
I bought a new and bigger Kobo, it seems the optimal dimension for bitmap PDFs are 1080x1306 for that one.