root@bipul-VirtualBox:~/Workplace/ffmpeg# ffmpeg -i akiyo_qcif.yuv a01.m4v
ffmpeg version 0.8.6-4:0.8.6-0ubuntu0.12.04.1, Copyright (c) 2000-2013 the Libav developers
  built on Apr  2 2013 17:00:59 with gcc 4.6.3
*** THIS PROGRAM IS DEPRECATED ***
This program is only provided for compatibility and will be removed in a future release. Please use avconv instead.
[IMGUTILS @ 0xbfc87144] Picture size 0x0 is invalid
[IMGUTILS @ 0xbfc87074] Picture size 0x0 is invalid
[rawvideo @ 0x858e240] Could not find codec parameters (Video: rawvideo, yuv420p)
[rawvideo @ 0x858e240] Estimating duration from bitrate, this may be inaccurate
akiyo_qcif.yuv: could not find codec parameters
root@bipul-VirtualBox:~/Workplace/ffmpeg# ls
akiyo_qcif.yuv  ffmpeg
root@bipul-VirtualBox:~/Workplace/ffmpeg#