FFmpeg conversion error: At least one output file must be specified

Question

Installed FFmpeg and it shows version and all correctly.

But even info FFmpeg command itself shows

FFmpeg -i Alice_In_Wonderland.mp4

Gives message 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 what's the problem

Solution

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.

Comments

[John G]

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