[FFmpeg-devel] [PATCH] Adjusting accel flag of liba52

Rich Felker dalias
Thu Jan 17 19:11:23 CET 2008

On Fri, Jan 18, 2008 at 02:58:33AM +0900, KO Myung-Hun wrote:
> > not a generic API
> Should I use a API such as mm_support() instead of global variable? Or
> what do you mean ?

He means the API needs to be the same for all codecs. Codec-specific
APIs are not acceptable in ffmpeg. Also ffmpeg already has a way of
handling cpu capabilities for its own codecs, which should be reused.

> > non constant global
> Hmm... Do you mean 'a52_aceel' is not a constant global, or macros are
> need ?

Global variables are not allowed in ffmpeg unless they're pure
constants or always initialized to the same constant values
algorithmically in a way that's reentrant/threadsafe without the use
of any locking.

> What I intended was that user should initialize a52_accel variable with
> macros defined in 'mm_accel.h'.

The user should not have to initialize an a52-specific variable to
begin with. The user should not even know or care whether liba52 is
linked into libavcodec or not.


More information about the ffmpeg-devel mailing list