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tritical · 14th November 2004, 20:29

@Mug Funky
Double rate output can be added pretty easily so I'll go ahead and do that. The other options that TFM is currently missing and that will be added at some point are post-processing of combed frames and an exclusion band for ignoring subtitles or a logo.

@Chainmax
My original idea was for something similar in operation to fdecimate/changefps with a few modifications (mainly dealing with the radius around the calculated frame in which it will look for the frame to return). The nice thing about it is it is simple, pretty fast, and allows decimation to any framerate. However, there are downsides of such a method compared to 1-in-N decimation when you can achieve the desired framerate with 1-in-N decimation. Namely, 1-in-N decimation doesn't require setting a duplicate threshold or even trying to find duplicates if simply removing the most similar frame in each N frame cycle. This type of method usually works well with normal movies, but not anime/cartoons where for correct decimation you do need to detect duplicates. Also, when doing 1-in-N decimation and tracking duplicates (requires a duplicate threshold like the first method) you can correctly handle scenerios like this: http://neuron2.net/ipw-web/bulletin/...cimate+pattern which is not possible with a changefps/fdecimate type of method or with simply removing the most similar frame in a cycle. User overrides of the decimation would be easier to support with 1-in-N decimation then the other method, as well. So after thinking about it, I am planning on adding both an arbitrary frame rate decimation mode and a 1-in-N decimation mode since they each have advantages. I am also planning a two-pass mode for use with hybrid material (film, 60i, and 30fps progressive in one clip) and mkv's vfr support. If anyone else has ideas for a decimation filter don't be shy

.

A new thread might be useful, but thats more work then simply posting in this one

. Once TFM gets double rate output, post-processing, and an exclusion band I will definitely start a new one.

EDIT: Forgot to mention this, but there is also the possibility of having an N-in-M decimation mode, where like the 1-in-N method (and unlike the fdecimate/changefps method) you consider full cycles at a time. It would offer some advantages (maybe the best of both worlds?), but also has new problems and I haven't had time to think about it enough.

14th November 2004, 20:29	#60 \| Link
tritical Registered User Join Date: Dec 2003 Location: MO, US Posts: 999	@Mug Funky Double rate output can be added pretty easily so I'll go ahead and do that. The other options that TFM is currently missing and that will be added at some point are post-processing of combed frames and an exclusion band for ignoring subtitles or a logo. @Chainmax My original idea was for something similar in operation to fdecimate/changefps with a few modifications (mainly dealing with the radius around the calculated frame in which it will look for the frame to return). The nice thing about it is it is simple, pretty fast, and allows decimation to any framerate. However, there are downsides of such a method compared to 1-in-N decimation when you can achieve the desired framerate with 1-in-N decimation. Namely, 1-in-N decimation doesn't require setting a duplicate threshold or even trying to find duplicates if simply removing the most similar frame in each N frame cycle. This type of method usually works well with normal movies, but not anime/cartoons where for correct decimation you do need to detect duplicates. Also, when doing 1-in-N decimation and tracking duplicates (requires a duplicate threshold like the first method) you can correctly handle scenerios like this: http://neuron2.net/ipw-web/bulletin/...cimate+pattern which is not possible with a changefps/fdecimate type of method or with simply removing the most similar frame in a cycle. User overrides of the decimation would be easier to support with 1-in-N decimation then the other method, as well. So after thinking about it, I am planning on adding both an arbitrary frame rate decimation mode and a 1-in-N decimation mode since they each have advantages. I am also planning a two-pass mode for use with hybrid material (film, 60i, and 30fps progressive in one clip) and mkv's vfr support. If anyone else has ideas for a decimation filter don't be shy . A new thread might be useful, but thats more work then simply posting in this one . Once TFM gets double rate output, post-processing, and an exclusion band I will definitely start a new one. EDIT: Forgot to mention this, but there is also the possibility of having an N-in-M decimation mode, where like the 1-in-N method (and unlike the fdecimate/changefps method) you consider full cycles at a time. It would offer some advantages (maybe the best of both worlds?), but also has new problems and I haven't had time to think about it enough. Last edited by tritical; 14th November 2004 at 20:43.