Want to compress MJPEG videos

xnd · 01-09-2009, 01:50 PM

Hi,

I have a CanonPowershot S5IS and once in a while, I like to take videos. I noticed the oversize of the .avi files. The codec used by my camera to encode the video is MJPEG.

I would like to know if you guys know a (simple?) way to compress those videos in order to make them much smaller, so I can send them to my friends/family? Any (simple?) how-to to follow?

Thanks in advance,

XND

H_TeXMeX_H · 01-09-2009, 02:41 PM

Well, the simplest way is to use avidemux.

You can also use ffmpeg or mencoder.

As I have some movies of this type taken with a digital camera, I'll show you what I do.

First run 'ffmpeg -i' on the video and get:

Code:

bash-3.1$ ffmpeg -i photo-hq.AVI
FFmpeg version SVN-r16141, Copyright (c) 2000-2008 Fabrice Bellard, et al.
...
Input #0, avi, from 'photo-hq.AVI':
  Duration: 00:01:26.80, start: 0.000000, bitrate: 8539 kb/s
    Stream #0.0: Video: mjpeg, yuvj422p, 640x480, 30.00 tb(r)
    Stream #0.1: Audio: pcm_u8, 8000 Hz, mono, s16, 64 kb/s
At least one output file must be specified

This gives you info on the video.

To compress this a bit, encode it using libx264, libxvid, mpeg4, and even flv if you find the quality acceptable.

To do this I run:

Code:

ffmpeg -i 'input.avi' -sameq -aspect 4:3 -vcodec libx264 -r 30 -ab 64k -acodec libmp3lame output.avi

You can also try other audio codecs. Run 'ffmpeg -formats'.

For more on what these options mean see the documentation:
http://ffmpeg.mplayerhq.hu/ffmpeg-doc.html

farslayer · 01-09-2009, 02:42 PM

Have you looked at avidemux ? Depending on what version of Linux you are running it may be in your repositories for easy installation. This is a GUI based application that should make it fairly simple to re-encode video clips.

There are also command line options available, such as ffmpeg.

[edit]
I need to hit the submit button faster....

xnd · 01-09-2009, 02:47 PM

Woaw, thanks everybody. I'll try this tonight!

Thanks for your help!!!

XND