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installed ffmpeg and it shows version and all correctly.

but even info ffmpeg command itself shows

ffmpeg -i Alice_In_Wonderland.mp4

gives messgae like

FFmpeg version 0.5, Copyright (c) 2000-2009 Fabrice Bellard, et al.
configuration: --prefix=/usr --libdir=/usr/lib64 --shlibdir=/usr/lib64 --mandir=/usr/share/man --incdir=/usr/include --extra-cflags=-fPIC --enable-libamr-nb --enable-libamr-wb --enable-libdirac --enable-libfaac --enable-libfaad --enable-libmp3lame --enable-libtheora --enable-libx264 --enable-gpl --enable-nonfree --enable-postproc --enable-pthreads --enable-shared --enable-swscale --enable-x11grab libavutil 49.15. 0 / 49.15. 0 libavcodec 52.20. 0 / 52.20. 0 libavformat 52.31. 0 / 52.31. 0 libavdevice 52. 1. 0 / 52. 1. 0 libswscale 0. 7. 1 / 0. 7. 1 libpostproc 51. 2. 0 / 51. 2. 0 built on Nov 6 2009 19:11:04, gcc: 4.1.2 20080704 (Red Hat 4.1.2-46)

Seems stream 1 codec frame rate differs from container frame rate: 49.93 (9986/200) -> 49.92 (599/12) Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Alice_In_Wonderland.mp4':
Duration: 00:01:39.65, start: 0.000000, bitrate: 542 kb/s Stream #0.0(und): Audio: aac, 44100 Hz, stereo, s16 Stream #0.1(und): Video: h264, yuv420p, 480x270, 49.92 tbr, 24.96 tbn, 49.93 tbc At least one output file must be specified

Please tell me whats the problem

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up vote 2 down vote accepted

Just like the error message says, you need to give it an output file. The basic syntax would be

ffmpeg -i Alice_In_Wonderland.mp4 Alice_In_Wonderland.avi

You can (and probably should) add options such as in this:

ffmpeg -i Alice_In_Wonderland.mp4 -vcodec mpeg4 -vtag divx -vb 5000k -aspect 2.424 -r 23.976 -acodec ac3 -ac 6 -ab 384k Alice_In_Wonderland.avi

That will create a DIVX format file.

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thanks for your reply @gorilla. Actually it expects three more packages, i tried with some packaes installations , nothing worked. OS reinstalled everything and its working now. Thanks – Ela Apr 6 '10 at 11:31

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