[FFmpeg-devel] E-AC-3 in FFmpeg

Justin Ruggles justinruggles
Wed Nov 7 01:30:21 CET 2007


Aurelien Jacobs wrote:
> Bart?omiej Wo?owiec wrote:
> 
>> On sobota, 3 listopada 2007, Michael Niedermayer wrote:
>>> Hi
>>>
>>> On Fri, Nov 02, 2007 at 04:31:51PM +0100, Bart?omiej Wo?owiec wrote:
>>>> Hi,
>>>> During GSoC I wrote E-AC-3 decoder. When I have free time I'll try to
>>>> send next patches to add the code to FFMpeg SVN. I enclose changes which
>>>> are needed in ac3dec.c to allow using parts of code in eac3dec.c.
>>> please split the (ff_ addition and static removial) from the rest!
>>>
>>> also newly added variables should have sensible names, that is
>>> s/flg/flag/
>>> s/bnd/band/
>>>
>>>
>>> [...]
>> Hi,
>> ok, I've split the patch and now I send the first part, where  ff_ac3 prefixes 
>> were added and  static from few functions was 
>> removed.
> 
> Patch looks OK, but I guess Justin is the one who should give
> the final OK (and who should commit ?).
> 
> Aurel

It also looks good to me except 1 thing.  I don't like that do_imdct() 
will be essentially duplicated verbatim in the E-AC-3 decoder.  The 
first solution that comes to mind is a shared AC3MDCT struct to hold 
most of the context variables used in that function:
tmp_output, delay, window, tmp_imdct, imdct_256, imdct_512, dsp

blksw, transform_coeffs, and output could be passed in as arguments to 
the shared function.  ...or everything could all be passed as arguments, 
but that would be pretty messy.

Once everything is approved, Bartek can commit it.

-Justin




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