Re: [Linux-uvc-devel] Logitech Quickcam for Notebooks Pro

[Luc S. <lu...@sa...>]

On Tue, Jan 31, 2006 at 08:07:05AM -0800, Binary Xerroz wrote:
 
> Well the jpeg_decoder function found in utils.h seems to be decoding to YUYV
> (v4l format 411P shows an uglier picture than with format YUYV, so this is
> based on this, even though in the function it says 411 encoding)

I've not use the jpeg decoder in utils.c for some reasons:

 - GPL licence impcompatible with MPL (pwlib licence on which ekiga is based)
 - use integer precision for DCT (i prefer to use float, or others)
 - readability (i learn a lot in writing my own tools).
 - can convert directly in RGB24, YUV420P, Gray or only return some
   components without decoding the full image.
 - ... because i like only my code :-)
 
> Also, <mplayer base dir>/postproc/, contains functions and libraries and
> what not to convert YUYV streams into apparently many others.

Yes ffmpeg (libavcodec, libavformat) is cool but sometimes you don't want the
full library as a dependancy or for legal reason (patent).

> Im going to try to find an algorithm from mplayer to convert the YUYV stream
> into i guess YV12  as im told its more umm supported? if i can ill add it to
> my program uvcStreamer and see if it yields any results.

YV12 is YUV420 ? Take a look at my tinyjpegdecoder library :-). Ok it's not
released but i'll send you the files.

Luc