[MEncoder-users] rip dvd to mkv, ogm, mp4 script

[James Hastings-Trew]

Martin Matusiak wrote:
> Hello James,
>
> That was quite a handful. Is this "it" on deinterlacing? As in all of
> the possible cases that can be used as a universal strategy?
>
>   
It's not perfect - nothing is. I've encoded a lot of DVDs into .avi and 
.mp4 formats, and you can always be thrown a curve-ball or find 
something in a title that goes outside norm.

Examples:
Just about every Disney DVD I've encountered has the main film at 
23.976, but the very start of the movie has several frame rate switches 
from video to film for the various logo and title cards that come up 
first. This could confuse the algorithm I outlined into believing that 
the title is "mixed" frame rate, when it is just film with some wonky 
stuff at the start. The best workaround is to do the detection on the 
2nd chapter, rather than the first.

Every Simpsons episode is done at film rate, but the intro has several 
video edits and inserts (the part where Bart draws on the blackboard is 
interlaced video, for example), and there will be several edits that 
break telecine cadence throughout the episode. The thing should be 
treated as "mixed" because the vast bulk of the video is actually 
progressive film but there are so many edits at the start that it will 
fool the algorithm into thinking it is video.

Japanese Anime DVDs can be particularly problematic, especially if the 
material was originally done for TV, because they have a tendency to 
hard telecine the progressive material, and then mix in video-rate 
scenes and edits. The algorithm might decide that these are "mixed" 
rate, but really should be treated as video.

Aside from those examples, the method has proven to be very good for my 
purposes.