Nevermind, the *4 factor messes up other tests. I guess the real
driver latency should not be hacked.

On Nov 11, 11:11 am, RockNCode <[email protected]> wrote:
> HI.
>
> I'm currently working on anAVsyncissue seen on froyo, seen mainly
> with low audio sampling rates. Basically, I'm seeing that the video is
> about 300 ms ahead of the audio. Now I've narrowed down the issue to
> this formula in AudioTrack.cpp
>
> mLatencyUs= afLatency + frameCount*1000/sampleRate.
>
> mLatencyUs is used to calculate the realTimeClock, used by the avsync
> algorithm in the Awesome player.
>
> The afLatency is the audio latency reported by our audio HAL. For our
> case it is reporting 92.8 ms (4096 buffer, 44100 sampling rate). The
> second term of this formula is always giving me 371.5-372, which is 4
> times the latency reported by the audio HAL. By doing experiments,
> I've found that multiplying afLatency by 4 at audio HAL level (so
> mLatency would be 372 + 372), is giving me goodavsync.
>
> does it makes sense to anyone what I'm doing ?
> is mLatency just used foravsync?
> Could I have other bad consequences to increase the afLatency value ?
> So far I haven't seen any.
>
> Thanks.

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