Correctly IVTCing ~20fps silent films

Hey folks, So I've been working with a lot of old silent films recently. My sources are relatively good MPEG-2 encodes at 60i. There are lots of "old film" artifacts, but I'm leaving those in. I will be encoding with x264 at ~1.3 mbit, which usually looks okay. Most of these silent films appear to have a true frame rate of 19.98fps progressive. When I bob-deinterlace and inspect the fields, I get a 3:3 (AAA:BBB) pattern, which seems simple enough. Now, I've been performing IVTC by just decimating the result like this: Code:

Your post has inconsistences and ambiguities. E.g., you talk about throwing away 4/6 of the fields, but you also say that the base frame rate is 19.97. That doesn't compute. Have you tried: telecide(post=0) decimate(3) You should post a link to an unprocessed source sample with good motion for a definitive analysis.

Neuron2, Sorry to confuse! I merely mean that when I bob-deinterlace, I end up throwing away 4 of the 6 interpolated frames to recover the original frame rate. I'm not totally familiar with IVTC. That much is apparent! From what I understand, a field matcher like telecide or TFM attempts to re-create the original frames by matching fields, as opposed to interpolation. Compare this to bob-deinterlacing, which interpolates a full frame from each field. From my understanding, since a bobber like tdeint(mode=1) interpolates each field to re-create frames, there would be less spatial resolution in each of these frames than if I had successfully field matched them. In that case, no interpolation would have been performed. This situation would have been considerably simpler for me to understand / explain if bobbing the input would have literally produced a clean pattern of 3:3. This wasn't the case, as some of these frames were blended and weren't spatially identical. I guess I'll stop trying to explain what I don't fully understand! Here's an unprocessed sample from a Charlie Chaplin film. The artifacts I mentioned can be clearly seen with a simple tdeint(mode=1). Your suggested telecide/decimate works well, but leaves a few combs. Vinverse terminates them. Thank you very much for your time and input. I may be the expert where I work, but I'm definitely still learning - as you can tell! I appreciate your teaching. ~MiSfit

Here's another sample - this one has a very different pattern. I couldn't get a lock on it...

@Blue_MiSfit, Well first up you should not be using a bobber. Bobbing is for completing frames out of fields for genuinly interlaced content, e.g. sports broadcasts, etc. You have chosen the right term IVTC, InVerse TeleCine, this involves matching top and bottom fields together to recover original progressive frames. No interpolation is required you have complete top and bottom fields for each frame, you just need to match them up. If the original film was captured appropriatly then each field should be from 1 original film frame, i.e. there should be no blending or film gate transition junk. Use this script to inspect the nature of fields in your stream. Code: