[Ffmpeg-devel] [PATCH] ac3 decoder

Justin Ruggles jruggle
Tue Oct 3 02:52:49 CEST 2006


Justin Ruggles wrote:
> Fabrice Bellard wrote:
> 
>>Benjamin Larsson wrote:
>>
>>
>>>Here is the patch with the ac3 decoder from SoC. Included is the patch
>>>to enable the sse imdct from Loren Merrit.
>>>
>>>MvH
>>>Benjamin Larsson
>>
>>
>>IMHO, the AC3 decoder bit allocation should be factorized with the 
>>encoder one (it should be by construction exactly the same function !).
>>
>>Regards,
>>
>>Fabrice.
> 
> 
> The decoder & encoder bit allocation functions definitely have identical
> results, but they are implemented slightly differently.  Unless someone
> else does it first, I'll make an attempt at a common version this
> weekend.  Also, there is some opportunity for optimization in both the
> encoder and decoder implementations.  For example, when exponents & bit
> allocation parameters are reused from the previous block, most of the
> bit allocation routine can be skipped.

I've been doing some work on this, and I've come to realize it will take
quite a bit of reworking to reduce code duplication since the decoder
passes the whole context into the bit allocation function.  Also, since
this is not my patch, I don't want to step on any toes here.  Is
Kartikey still working on this?  Should I submit my suggestions as an
alternate patch?  or a patch against the patched version?

-Justin




More information about the ffmpeg-devel mailing list