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I created a video clip using ffmpeg (vcodec: mpeg2video, acodec: AC3 5.1).

The file can be played normally on Ubuntu, but when I play it on an XP machine, there is no sound. I can play AC3 files and other movies with AC3 sound. I already tried many codec packs and many players.

When I compare the MediaInfo tab of the Properties window of the file with another playable movie, I see that the Audio Identifier of the audio stream in my file is 0x80 while it is 0x02 in the other movie.

So I guess that's why players on XP can't recognize the audio codec. When I use an MKV container instead of MPEG (still mpeg2video codec), then the result is OK on both Ubuntu and XP (with the correct Audio ID). I really need MPEG though.

Any idea?

This is the command I used:

~/ffmpeg/ffmpeg/ffmpeg -loop_input \
  -t 97 -r 30000/1001 -i v%4d.tga -i final.ac3 \
  -vcodec mpeg2video -qscale 1 -s 400x400 -r 30000/1001 \
  -acodec copy -y out6.mpeg 2

This is the output of mediainfo (on Ubuntu):

General
Complete name                    : out6.mpeg
Format                           : MPEG-PS
File size                        : 6.86 MiB
Duration                         : 1mn 37s
Overall bit rate                 : 593 Kbps

Video
ID                               : 224 (0xE0)
Format                           : MPEG Video
Format version                   : Version 2
Format profile                   : Main@Main
Format settings, BVOP            : No
Format settings, Matrix          : Default
Format_Settings_GOP              : M=1, N=12
Duration                         : 1mn 37s
Bit rate mode                    : Variable
Bit rate                         : 122 Kbps
Width                            : 400 pixels
Height                           : 400 pixels
Display aspect ratio             : 1.000
Frame rate                       : 29.970 fps
Resolution                       : 8 bits
Colorimetry                      : 4:2:0
Scan type                        : Progressive
Bits/(Pixel*Frame)               : 0.025
Stream size                      : 1.41 MiB (21%)

Audio
ID                               : 128 (0x80)
Format                           : AC-3
Format/Info                      : Audio Coding 3
Duration                         : 1mn 36s
Bit rate mode                    : Constant
Bit rate                         : 448 Kbps
Channel(s)                       : 6 channels
Channel positions                : Front: L C R, Side: L R, LFE
Sampling rate                    : 44.1 KHz
Stream size                      : 5.18 MiB (75%)
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What players have you tried on Windows? For example in VLC, what does it say in the "Info" window about your file? What do you see under Audio » Audio Track or Channels? –  slhck Nov 22 '11 at 8:45
    
Hi slhck, I tried VLC, Nero, WMP, WM Classic. The Info window of VLC does not contain anything (except filename). But the Codecs tab shows a long list of 110 streams. The first one is video with MPEG2 codec, second is subtitle, others are audio with different codecs. The Tracks menu shows 18 tracks with a check mark on Track 1. –  Andy Le Nov 22 '11 at 21:16
    
110 streams? There's definitely something wrong there. I can't think of anything else to try at the moment though. I wonder if VLC shows the same on Ubuntu? –  slhck Nov 22 '11 at 21:31
    
To my surprise, on Ubuntu, the Codecs tab shows 37 streams, while Tracks menu shows 22 tracks :) Probably this is a bug of ffmpeg? –  Andy Le Nov 23 '11 at 4:16
    
Could very well be! Do you have the latest version? –  slhck Nov 23 '11 at 8:05
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1 Answer

up vote 0 down vote accepted

After long time struggling with the problem, I found a way to work around:

first encode using ffmpeg without sound

ffmpeg -loop_input -t 97 -r 30000/1001 -i v%4d.tga -s 400x400 \
-vcodec mpeg2video -acodec copy -f mpeg -y -r 30000/1001 test7.mpeg

then use mencoder to merge the video and the sound

mencoder -of mpeg -ovc copy test7.mpeg \
-audiofile Final.ac3 -oac copy -o test8.mpeg

The output from mediainfo remains almost the same as before, but the sound is now OK. I don't know why. I tried to compare the two files with cmp, but there are too many differences so I couldn't figure out anything.

I hope in the future I can use ffmpeg to do all in one step.

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