[MPlayer-users] problem with Too many audio packets in the buffer

[Philip Walden]

I am trying to use mencoder as as transcoder for a minidlna. Basically 
mencoder get called to transcode the source video into mpeg2 DVD format. 
This works great except for some mp4 files I download from PBS.org. 
Other mp4/flv work fine. When I transcode these I get the "Too many 
audio packets in the buffer" error and it stops. I understand that one 
can encode the video and audio separately and then remux them in a 
second step, but the transcoder has to do it in one step.

If use ffmpeg to transcode, I have no problems. However, ffmpeg seems to 
be 2-3x slower on my system and I have trouble with some files that are 
very HD or have lots of noise/artifacts causing the bitrate to spike.

If anyone can suggest a different set of prarmeters I would appreciate 
the help. Here is the failing run. Dropping the harddup causes huge A/V 
sync issues. I have a Intel i3 3 GHz and 2GB of memory, so I don't think 
lack of machine resources is a problem.

$ mencoder -oac lavc -of mpeg -mpegopts 
format=mpeg2:muxrate=25000:vbuf_size=1194:abuf_size=64 -vf 
scale=720:480,harddup -ovc lavc -lavdopts debug=0 -lavcopts 
autoaspect=1:vcodec=mpeg2video:vbitrate=8000:acodec=ac3:abitrate=128:keyint=18:vqscale=1:vqmin=2 
-subdelay 20000 -ofps 30000/1001 -mc 0 -noskip -af lavcresample=48000 
-srate 48000 -o test.mpg NOSN_CanWeMakeItToMars.mp4
MEncoder SVN-r31628-4.4.4 (C) 2000-2010 MPlayer Team
success: format: 0  data: 0x0 - 0x1135caeb
libavformat file format detected.
[flv @ 0x9ebcdd0] Estimating duration from bitrate, this may be inaccurate
[lavf] stream 0: video (h264), -vid 0
[lavf] stream 1: audio (aac), -aid 0
VIDEO:  [H264]  512x288  0bpp  15.000 fps    0.0 kbps ( 0.0 kbyte/s)
[V] filefmt:44  fourcc:0x34363248  size:512x288  fps:15.000  ftime:=0.0667
==========================================================================
Opening audio decoder: [faad] AAC (MPEG2/4 Advanced Audio Coding)
FAAD: compressed input bitrate missing, assuming 128kbit/s!
AUDIO: 44100 Hz, 2 ch, s16le, 128.0 kbit/9.07% (ratio: 16000->176400)
Selected audio codec: [faad] afm: faad (FAAD AAC (MPEG-2/MPEG-4 Audio))
==========================================================================
PACKET SIZE: 2048 bytes, deltascr: 17694
Opening video filter: [expand osd=1]
Expand: -1 x -1, -1 ; -1, osd: 1, aspect: 0.000000, round: 1
Opening video filter: [harddup]
Opening video filter: [scale w=720 h=480]
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffh264] vfm: ffmpeg (FFmpeg H.264)
==========================================================================
[ac3 @ 0x9fecd50] No channel layout specified. The encoder will guess 
the layout, but it might be incorrect.
Limiting audio preload to 0.4s.
Increasing audio density to 4.
Movie-Aspect is 1.78:1 - prescaling to correct movie aspect..000 [0:0]
[swscaler @ 0xa06b0a0] BICUBIC scaler, from yuv420p to yuv420p using MMX2
videocodec: libavcodec (720x480 fourcc=3267706d [mpg2])
[VE_LAVC] Using constant qscale = 1.000000 (VBR).
Writing header...
INITV: 0.200, 0.167, fps: 29.970
Pos:  95.7s   2868f ( 6%) 154.90fps Trem:   4min 1082mb  A-V:0.000 
[5747:128]
Too many audio packets in the buffer: (4096 in 3776561 bytes).
Maybe you are playing a non-interleaved stream/file or the codec failed?
For AVI files, try to force non-interleaved mode with the -ni option.

Flushing video frames.
Writing index...

Overhead: 1.397% (940131 / 67305373)
Writing header...

Video stream: 5747.125 kbit/s  (718390 B/s)  size: 68722852 bytes  
95.662 secs  2868 frames

Audio stream:  128.000 kbit/s  (16000 B/s)  size: 1537024 bytes  96.064 secs
[pwalden at walden8 NovaScienceNow]$ mencoder -demuxer help
MEncoder SVN-r31628-4.4.4 (C) 2000-2010 MPlayer Team
No file given

Exiting... (error parsing command line)


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