[x264-devel] Regarding claiming for standard approval

[Loren Merritt]

On Thu, 31 Jan 2008, mahesh k wrote:

> I do find some difference in the quantization of X264 and our.

http://mailman.videolan.org/pipermail/x264-devel/2007-November/003729.html

> I think they are using function pointers. But my results are matching with
> JM.

Of course your results aren't identical to JM. Every encoder is different. 
What kind of screwed up standard would allow only a single possible 
encoder algorithm? Not even JM is identical to JM; it has tons of options, 
including multiple quantization algorithms.

> please let me know whether X264 is as per H.264 standard or not.

The definition of a compliant encoder is one that generates compliant 
bitstreams. So try this thought experiment: Given a h264 stream (and only 
the compressed stream, assume you don't have access to the original source 
video), can you tell what quantization algorithm was used to generate it? 
No? Then quantization can't have any impact on standards compliance.

--Loren Merritt