Re: YUV format

On Thu, 26 Dec 2002, Holger Waechtler wrote:

> well, IIRC I was able to encode and decode about 20 frames/sec at CIF
> resolution on a Duron with 800 MHz at decent bitrates (about 3-8kBytes
> per frame). Without any optimisation.

I am using an Athalon 1800 for my test machine.  Frame size for this clip
is 512 x 384.

> > also modified the tarkin_sdl_player to use YUV overlays so it can handle
> > the native YUV12 format.  Playback appears to be at 1 frame every 1 - 2
> > seconds, and after a few frames the image degrades into random patterns.
>
> ?!?
>
> > Have I really messed something up, or is this the current state of the
> > codec?  I am running the encoder as
> >
> > tarkin_enc_yuv stream.yuv 100000 2 2
>
> Why do you want to use such high bitrates?

I don't!  But I started out at 1000, and it was only random patterns, so I
went to 3000 and it was only slightly better so I decided to just turn it
way up and see if there was any decent quality at a high extreme.

> > I also tried with 3000 instead of 100000 and it just made larger Moire
> > patterns.
>
> you have to deinterlace your movies before encoding.

I believe this one is already deinterlaced, the same source file works
fine with the Theora code, and it only supports non-interlaced as well.

> After all you should remember that this code is for research, it
> compresses oonly in statial domain and does not exploits any temporal
> coherence.

I realized that is only experimental, hopefully I can help move it along a
bit.

> So you have to compare it to still image comression algorithms, not to
> video codecs unless you add a motion compensation scheme before.

I am hoping to do that, if I can get some decent images and processing
speed to start with.

Ed Okerson

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