[FFmpeg-devel] [PATCH] force mono for speex in flv

Justin Ruggles justin.ruggles
Sun Jun 21 21:27:58 CEST 2009

Michael Niedermayer wrote:
> On Sun, Jun 21, 2009 at 02:43:25PM -0400, Justin Ruggles wrote:
>> Hi,
>> FLV only supports mono Speex audio.  This patch forces mono, ignoring
>> the SoundType flag, which is what should be done according to the SWF
>> and FLV specifications.
> does this fix something with an actual file?

The sample files I've seen all have the correct SoundType value, but the
spec explicitly says that it should be ignored.

"The SoundType and SoundSize fields are also ingored[sic] in the case of
Speex. Speex in SWF is always mono and always decodes to 16-bit audio
samples internally."


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