A simple Linux DVD HOWTO in a command line

Posted on by acme

The Problem

You’ve got two .avi video files, and tovid didn’t work for you, but you need a DVD, because the person who wants to play this back only got an DVD-player.
Note:All the commands mentioned below are in the default Ubuntu Repo. I’m using Kubuntu 8.10 Intrepid Ibex right now, but it should work for every other Distro, too. If a command does not work for you, because it’s not installed, use on Debian-systems apt-get search application-name ( aka aptitude search application-name ) to install the missing application.

Analyzing the footage

Please first have a look at all possible aspect ratios. These are the available aspect ratios, but other rations are also possible, but only ratio 4/3 and 16/9 are valid ratios for dvdauthor. You can see easily how much information is lost if you have to crop or expand (reduce).

  • 4/3 – old TV-set (Cathode Ray Tube -> CRT)
  • 16/9 – CRTs, Plasmas and TFT TV-sets
  • 2.21 – Cinema
aspect ration 4/3 on old CRTs aspect ratio 16/9 on recent plasmas or TFTs anamorphic aspect 2.21:1 usually for cinema not a big loss: 2.21:1 on 16/9

Now it’s getting a little difficult. First you have to make up your mind about the result you want to have. Do you want to crop (cut out) the image, if your TV-set can’t handle anamorphic widescreen (I don’t know of one, who does 😉 )? Or do you want do add black bars to your screen, so the whole picture get smaller? Well, if you really have got anamorphic widescreen (2.21:1), or even worse (see example below (2.50:1), it’s recommended to crop the center part of the video, although you are throwing away information which are to the left and to the right of the screen. How much it is, can be seen on the pictures at this page.

If you made up your mind, whether it is better to drop information from the left or the right side, or drop information by constantly throw away every nth pixel by scaling down the whole picture, then you have to choose from these two methods:

  • crop: cutting off edges from the left and right side
  • expand: adding black bars at top and bottom of screen

Start the analyzing process just by simple starting the mplayer and hitting after mplayer started the Ctrl+c. Look for “Movie-Aspect is“, and please consider, that “2.21” ratio is not a valid ratio for dvdauthor. If you should use aspect=2.21 or even 2.50 like in this example, dvdauthor will prompt this warning:

WARN: unknown mpeg2 aspect ratio 4

mplayer my_input_video.avi
MPlayer dev-SVN-r27800-4.3.2 (C) 2000-2008 MPlayer Team
CPU: Intel(R) Core(TM)2 Quad CPU Q6600 @ 2.40GHz (Family: 6, Model: 15, Stepping: 11)
CPUflags: MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 1
Compiled for x86 CPU with extensions: MMX MMX2 SSE SSE2
129 audio & 259 video codecs

Playing my_input_video.avi.
AVI file format detected.
.
.
.
Starting playback...
VDec: vo config request - 640 x 256 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 2.50:1 - prescaling to correct movie aspect.
VO: [xv] 640x256 => 640x256 Planar YV12

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