[patch] - bbsplash applet

Ralf Friedl Ralf.Friedl at online.de
Tue Mar 4 15:54:11 UTC 2008


Paul Fox wrote:
> ralf wrote:
>  > Paul Fox wrote:
>  > > you should replace ppm with just one image format -- a raw binary
>  > > format that exactly matches the framebuffer format.
>  ...
>  > The binary PPM format as almost as raw as it can get, while keeping 
>  > information about the file size.
>
> i don't understand how a single PPM binary format can match various
> framebuffer depths.  (and -- i may be wrong on this -- don't framebuffers
> differ in pixel encoding, as well?  RGB vs. BGR, 565 vs. 556, etc?)
>   
PPM is normally RGB 888.
I assumed that is also the format of the frame buffer, as these days 
every graphics adapter should have enough memory for 24 bit.
>  > The conversion of binary PPM to raw rgb can normally be done with "tail 
>  > -n +4", although a program "ppmtorgb3" is also available for files with 
>  > unusual line breaks or bit depths.
>
> again, i don't understand.  ppmtorgb3 creates three files.  how
> does this help with writing a framebuffer?
I was wrong in my assumption about ppmtorgb3.

Regards
Ralf Friedl



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