Re: OT: Why? Using eeePC as digital photo frame with server push...

Jan Panteltje wrote:
On a sunny day (Thu, 04 Sep 2008 21:43:58 +0100) it happened Martin Brown
<|||newspam|||@nezumi.demon.co.uk> wrote in
<da2b8$48c0488a$11340@xxxxxxxxxxxxxxxxx>:

One version of the Fuji Frontier photolab quality colour printer firmware had a curious fault that meant it worked perfectly with any 24bit YCC encoded JPEG but gave a completely surreal random false colour map to pure single channel monochrome 8bit JPEGs (consistent but nothing like an 8 bit greyscale). The effect was highly amusing whilst it lasted.

I suspect at least one JPEG codec still has a quirk when faced with unusually encoded images. The PaintShopPro encoder from v8 onwards is actually terminally broken in chroma subsampling but hardly anyone has noticed. The IJG codec is a pretty good reference JPEG implementation.

In a first test I managed to get some pics working in ffmpeg by using
Imagemagick's 'convert' to first convert from jpg to ppm (RGB format),
and then from ppm to jpg again... but it still got into problems with some BW.
I used libjpeg.so.62.0.0 for my own program, and simply added
code for cinfo.out_color_space == 1, late last night, so simple, worked
to my amazement.
Now no more need to pre-process via 'convert' other then getting all pics the
same size and screen filling on the target screen, and it does create
predictable formats, keeps aspect right.
It is nice to have all the open source libs, and manuals.
There must a be lot of desperate crying users out there trying to do what
the soft does not do :-), and being unable to do anything about it.
For MS windows I mean....
They then usually get recommended an other $$$$$ application.....


Nah. Believe it or not I organize and scale many of my pictures with, gasp, MS-Word. A pretty old version of it to boot. PowerPoint works, too.


In Linux the imagemagick program suite is pretty good for most picture
manipulations, and this is one of the first times ffmpeg failed on me.


--
Regards, Joerg

http://www.analogconsultants.com/

"gmail" domain blocked because of excessive spam.
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