if use c44 - add --crcb options

[GoogleCodeExporter]

-crcbnormal 
-crcbhalf 
-crcbdelay n 
-crcbfull 
-crcbnormal and -crcbdelay 0. 
-crcbnone 

may be useful to get higher image quality
sometimes your pdf2djvu produces awful images

Original issue reported on code.google.com by mivan...@gmail.com on 18 Nov 2012 at 6:45

[GoogleCodeExporter]

and comment - what crcb opt uses your pdf2djvu

Original comment by mivan...@gmail.com on 18 Nov 2012 at 8:42

[GoogleCodeExporter]

pdf2djvu uses c44 only in very exceptional situations: to create a solid-color 
(non-white) background. It doesn't call it with any --crcb* options, so the 
default --crcbnormal is being used.

In all other cases, pdf2djvu uses csepdjvu to create IW44 layers, which doesn't 
have any options to control resolution of chrominance encoding.

Original comment by jwilk@jwilk.net on 5 Dec 2012 at 7:21

• Changed state: WontFix
• Added labels: Type-Enhancement, Priority-Low, OpSys-All, Component-Logic, Usability

[GoogleCodeExporter]

i convert pdf with raster images and c44 opts has great effect on img quality
images was lowcolor (32color) and it was hard to obtain acceptable quality with 
same size
so the idea is to code such pdf with lowcolor opts of c44 to reach high 
compression with same quality.
present 0.7.14 codes such images in excessible sized iw44 chunks... why crcb 
opts omitted? it can be helpful...

Original comment by mivan...@gmail.com on 6 Dec 2012 at 3:22

[GoogleCodeExporter]

--bg-subsample=n
Specifies the background subsampling ratio. The default is 3. Valid values are 
integers between 1 and 12, inclusive

so that option provided by what?

question created by wierd results - screenshots good compressed with 300-1000% 
increased file size...

Original comment by mivan...@gmail.com on 6 Dec 2012 at 4:22