[MPlayer-users] [Bug] MPlayer decoded aac stream has longer duration than original

Zhou Zongyi zhouzy at os.pku.edu.cn
Sat Sep 19 18:50:20 CEST 2009

Hi all,

The bug can be reproduced in the following way:

1) Encode a wav file with NeroAacEnc or any other aac encoder.
2) Decode the mp4/m4a file with mplayer by -ao pcm:file=out.wav

out.wav has longer duration than the original wav file. By comparing the two PCM side by side,
I found that a delay is added to beginning of the decoded wav file.

The length of the delay depends on samplerate and settings. HE-AAC and lower samplerate has longer delays.
HEv2 @ 44100Hz has a delay as long as 112ms, which is obviously audible.

NeroAacDec and foobar2000 has no such problem.

Any idea to fix it?


Zhou Zongyi

More information about the MPlayer-users mailing list