Scanning Suggestions (Bookmarks & Colour)

[Antonio Carlini]

On 28/08/2021 09:21, æstrid smith via cctalk wrote:
> i've achieved satisfactory results paletteizing scans of low-color-depth material using a tool called 'noteshrink':
>
> https://mzucker.github.io/2016/09/20/noteshrink.html
>
Well as a guide the 66 page AA-CJ39A-TE (VAX-11 RSX Installation Guide 
and Release Notes) is 8.8MB. That's with the front and rear cover 
scanned as 300 dpi JPG and also 12 colour pages as 300 dpi JPG.

Each of the 600dpi PNG pages comes out at 26MB.

I tried optipng first. Even "-o 7" (which I ran overnight but I forgot 
to time ...) only dropped a page down to 19MB. So completely impractical 
for even this small number of pages.


Noteshrink (which I've seen before but never bothered to try!) knocked a 
26MB PNG down to 700kB. The only issue is that the red looks quite a bit 
more brown than it should. I'll look into it a bit more as it looks 
good. Thanks


Antonio


-- 
Antonio Carlini
antonio at acarlini.com