[Ffmpeg-devel] aac adts input

Justin Ruggles jruggle
Wed Aug 10 04:12:13 CEST 2005

Justin Ruggles wrote:
> As an odd side note, I have an aac audio clip with samplerate 22050 Hz,
> and FFplay is playing it at half-speed.  FFplay reports the correct
> samplerate...it just sounds funny.  When muxed into mp4 with video, it
> plays both the audio & video at half-speed.  It plays correctly in
> MPlayer and with faad.

I think I've solved this.  It seems that faad automatically upsamples
the 22050 Hz to 44100 Hz.  The avctx->sample_rate is changed to 44100 by
the faad configuration.  The problem lies in that SDL is initialized
before the codec, so it plays at 22050 while faad outputs at 44100.

Patch coming soon.

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