On 27/08/2021 22:05, Paul Koning wrote:
JPG is the wrong tool for pages with color text or
color line art. As
I've mentioned before, JPG is fit ONLY for photos, not for any image
with hard edges. Text compressed with JPG will suffer badly.
Yes, true. I thought that for colour, all I could get was JPEG. It
certainly seems to be the case that the HP PhotoSmart I have scans
everything as JPEG 300 dpi when you use the front panel to scan to a
memory stick. Post processing wouldn't make that any better, which is
why I thought I was stuck with JPEG.
It turns out though that if you drive it with a computer then you also
get the choice of TIFF or PNG as additional choices. TIFF is likely to
be quite a bit too big. I'll try PNG and see how big the files it
generates are. I've no idea what the default compression is straight out
of the software but as long as it's lossless I can hopefully
post-process to squeeze things down if possible.
If this turns out to work without ballooning file sizes, then I can just
not bother preserving the B&W pages, as lossless colour PNG should OCR
as well as B&W (I would think).
I have a few pages in the scanner now at 600dpi PNG so I'll soon know
how that compares to JPG or B&W.
antonio at acarlini.com