avenc_mpeg2video: Default bitrate too low

Submitted by VanillaMozilla

Link to original bug (#644919)

Description

I was trying to create a video DVD VOB file with ffmux_dvd. The only video encoder listed for that container is ffenc_mpeg2video. The default bitrate is only 300000, which gives a very blocky appearance with poor resolution, especially in darker parts of the image. A more reasonable value of 6548000, which I found somewhere on the "Interwebs", maintains the quality of the original file, and also yields an approximately correct file size for the length of the DVD.

I started with an ordinary NTSC DVD, with 480x360 resolution. Preferred behavior would be for PiTiVi not to degrade the quality of the input files by default. If that's too difficult, an acceptable way to fix the problem would be just to choose a correct value for normal DVD quality.

A word about the severity. Although this should be a simple problem to fix, I'm marking the severity as "major", because it always yields poor quality output for DVDs. The average user (me) is already overwhelmed by the huge number of options and parameters, while simultaneously troubleshooting multiple problems with video software.