Welcome to WebmasterWorld, powerflash.

What is the issue you are having? What are you trying to accomplish? Are you trying to run this command using a PHP function then?

No,no I run this script in console like the root login

I tried with 3gp format but this is problem

ffmpeg -i /home/user/www/video/3gp.3gp -y -acodec mp3 -ar 22050 /home/user/www/video/vid.flv

FFmpeg version SVN-r8630, Copyright (c) 2000-2007 Fabrice Bellard, et al.
configuration: --enable-libmp3lame --enable-libogg --enable-libvorbis --disable-mmx --enable-shared --enable-amr-nb --enable-amr-wb --enable-gpl --enable-liba52 --enable-xvid
libavutil version: 49.4.0
libavcodec version: 51.40.2
libavformat version: 51.11.0
built on Apr 6 2007 11:01:20, gcc: 3.2.3 20030502 (Red Hat Linux 3.2.3-56)
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from '/home/user/www/video/3gp.3gp':
Duration: 00:00:12.0, start: 0.000000, bitrate: 77 kb/s
Stream #0.0(und): Video: h263, yuv420p, 176x144, 29.97 fps(r)
Stream #0.1(und): Audio: samr / 0x726D6173, 8000 Hz, mono
Output #0, flv, to '/home/user/www/video/vid.flv':
Stream #0.0: Video: flv, yuv420p, 176x144, q=2-31, 200 kb/s, 29.97 fps(c)
Stream #0.1: Audio: mp3, 22050 Hz, mono, 64 kb/s
Stream mapping:
Stream #0.0 -> #0.0
Stream #0.1 -> #0.1
Unsupported codec (id=73728) for input stream #0.1

Well, it's beyond me, I'll tell you that much. I'll move the thread over to the WebmasterWorld Site Graphics and Multimedia Design [webmasterworld.com] forum to see if perhaps any of the folks there might have some insight.

I checked the ffmpeg site - it doesn't look like it supports the 3gp codec. 3gp is a nokia codec used in their mobile phones.

Also, you are forcing ffmpeg to convert the audio using the "MP3" codec - but for that you need to have the LAME library installed. Check the ffmpeg documentation.