[MPlayer-users] Encoding 3gp, how?

[Benjamin Burkhart]

Hi there.

What I want to do is to encode video for a mobile phone. I have a file 
that's been produced by the phone in question. Here's the output from 
'mplayer -identify', and as I presume that the phone can play videos of 
this format, that's what I want to have.



Player 1.0rc2-4.3.3 (C) 2000-2007 MPlayer Team
CPU: Intel(R) Pentium(R) 4 CPU 3.20GHz (Family: 15, Model: 3, Stepping: 
4)
CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled with runtime CPU detection.

Playing 091115_142746_M.3gp.
ISO: File Type Major Brand: 3GPP Profile 5
Quicktime/MOV file format detected.
ID_VIDEO_ID=0
[mov] Video stream found, -vid 0
ID_AUDIO_ID=1
[mov] Audio stream found, -aid 1
VIDEO:  [avc1]  864x480  24bpp  30.303 fps    0.0 kbps ( 0.0 kbyte/s)
ID_FILENAME=091115_142746_M.3gp
ID_DEMUXER=mov
ID_VIDEO_FORMAT=avc1
ID_VIDEO_BITRATE=0
ID_VIDEO_WIDTH=864
ID_VIDEO_HEIGHT=480
ID_VIDEO_FPS=30.303
ID_VIDEO_ASPECT=0.0000
ID_AUDIO_FORMAT=mp4a
ID_AUDIO_BITRATE=16000
ID_AUDIO_RATE=16000
ID_AUDIO_NCH=2
ID_LENGTH=5.57
[ ... ]



What I have is a video from a compact digital camera. mplayer -identify 
says:

Playing CIMG3163.MOV.
ISO: File Type Major Brand: Original QuickTime
Quicktime/MOV file format detected.
ID_VIDEO_ID=0
[mov] Video stream found, -vid 0
ID_AUDIO_ID=1
[mov] Audio stream found, -aid 1
VIDEO:  [avc1]  640x480  24bpp  25.000 fps    0.0 kbps ( 0.0 kbyte/s)
ID_FILENAME=CIMG3163.MOV
ID_DEMUXER=mov
ID_VIDEO_FORMAT=avc1
ID_VIDEO_BITRATE=0
ID_VIDEO_WIDTH=640
ID_VIDEO_HEIGHT=480
ID_VIDEO_FPS=25.000
ID_VIDEO_ASPECT=0.0000
ID_AUDIO_FORMAT=285242221
ID_AUDIO_BITRATE=0
ID_AUDIO_RATE=22050
ID_AUDIO_NCH=1
ID_LENGTH=18.04
[ ... ]



Heres an mencoder command that I played around with:
mencoder CIMG3163.MOV -ovc lavc -lavcopts vcodec=libx264 -vf 
expand=864:480,scale=864:-2 -oac lavc -lavcoptsacodec=adpcm_ima_wav -af 
resample=8000 -srate 8000 -o test.3gp -ofps 12 -lavfopts format=mov

The phone does not play the movie from the digital camera without 
modification.

If anyone could give me pointers ...
Differences between the videos include:
- Width --> black bars on the sides are fine.
- FPS --> target is 30
- Audio format --> target is mp4a
- Audio bitrate -- 16000 vs 22050
- Audio nch (number of channesl?) --> 2

Any pointers, ideas? Thanks already.

Cheers,
Benjamin.