Convert Video on Linux for Nokia N97

you can save different configurations as profiles for mencoder use.

1. create configuration file ~/.mplayer/mencoder.conf if there is not.
if in windows, the file should be put in the same folder with config and input.conf

2. edit mencoder.conf

[n97]
profile-desc="MPEG4/AAC"
vf=scale=640:-3,harddup
ovc=lavc=yes
oac=lavc=yes
lavcopts=aglobal=1:vglobal=1:acodec=libfaac:vcodec=mpeg4:abitrate=96:vbitrate=896
af=lavcresample=44100
ofps=25
of=lavf=yes
lavfopts=format=mp4

[profile2]
..
..

the quality of video from the above setting is good enough. but you still can adjust them in the suitable range
abitrate: 96 ~ 192
vbitrate: 896 ~ 4000

3. specify which profile to use

mencoder -profile n97 -o output.mp4 input_file


Convert video by mencoder

mencoder is cross-platform command line video decoding, encoding and filtering tool. it can convert all the formats that MPlayer understands.

a converting example like below

mencoder in.video -oac mp3lame -lameopts preset=64 -ovc lavc -lavcopts vcodec=mpeg4 -ofps 25 -vf scale=320:240 -ni -o out.video

-oac #encode with the given audio codec (no default set).
-oac help #get a list of available audio codecs.
-<codec>opts #codec specific encoding parameters

preset=<value> #ABR encoding at average given kbps bitrate

-ovc #encode with the given video codec (no default set).
-oac help #get a list of available video codecs.

vcodec=<value> #employ the specified codec (default: mpeg4).
#windows media player comptiable format: msmpeg4, msmpeg4v2, wmv7

-ofps #specify a frames per second (fps) value for the output file
-vf scale=x:y #resize video

-ni #force usage of non-interleaved AVI parser (fixes playback of some bad AVI files).

-o #output filename