AVISynth 24p to 60i Telecine

[jelockwood]

I have seen plenty of articles on converting 60i to 24p and in these forums one to convert 24p to 30p, however I have a slightly more complex requirement.

Several years ago now I had a DVD of an old film that was only available as a butchered 4:3 cropped version. At around that time I also came across a very poor quality letterboxed widescreen capture of a LaserDisc version of the same film. Apart from the poor image quality of this capture it also had several timecode breaks in it. After considerable effort I was able to use AVISynth to convert the capture of the 60i LaserDisc frame rate to 24p, simultaneously fix the time code breaks, include steps to convert it to a 16:9 anamorphic display and do some significant image clean up. This along with a few other steps resulted in a DIY widescreen anamorphic DVD complete with menu and an 'extra' in the form of the official movie trailer and was vastly superior to the official commercial DVD. (Which had zero extras.)

I am considering having another go at this to try doing two things. Firstly while the video I produced via AVISynth was 24p and played perfectly and the DVD menu due to the tool I used for that could only be 60i, I don't like this mixture although it does no serious harm. Secondly I would like to improve the color balance if I can and would only bother doing this if I can resolve the frame rate issue.

So why is this going to be more complex? Ideally I would like to do the following in a single AVISynth script.

Input the damaged original video, process it as per my original AVISynth script to convert to 24p and simultaneously fix the time code breaks, do the anamorphic conversion, and then take the final result and convert it back to 60i with no time code breaks.

So my question is how would I do effectively two framerate conversions i.e. first inverse telecine and then redoing telecine all in one script? The reason I was thinking or hoping to take this approach was the assumption that this would save on one layer of encoding and preserve more quality.

[poisondeathray]

It's not necessary to introduce "hard" telecine by adding "physical" repeat extra fields. "Soft" telecine can be used for DVD by using repeat field flags. Every DVD compliant MPEG2 encoder can do this. Additionally, the quality will be higher from progressive encoding and fewer fields