Progressive/Interlaced Problem

[RevyJay]

I've ripped a movie from DVD. I ended up converting it to VCD. The last half of the movie ended up not being as smooth as the first. The movie skipped at a constant rate, which right away told me that it missed frames. I used FlaskMPEG preview section to find that about half way through the movie, it switched from Progressive to Interlaced. I also realized that the movie wanted to convert with a 25fps (This is a region 1 movie, U.S.A.). Then I started to calculate the total frames of the movie. The ripper's text file said there were over 165,000+ frames in the movie, but when I figured frame counts @ 23.976 AND 25 AND 29.976, none of the counts matched what the info file stated. My only thought is that the frame rate changed when it went from Progressive to Interlaced. Has anyone else ran into this problem, and if so, how would a person go about getting this to work so everything is smooth? Thanks for your time.

[kahm-jai]

Considering it's a DVD... I've only encountered a weird framerate of 20fps, and since you are converting to VCD, it MUST be 25, 29.97 or 23.something. The Converting program does not drop frames, it just didn't fit it's profile... 20 -->25 frames is not doubling the frames etc.. it does no interpolation so i guess yes.. you are dropping some frames there.. or at least it doubled like 5 of the 20 frames which makes a funny timeline.. or at least JERKY..

I encountered the same problem, but i have no solution to this whatsoever.. I've been fooling around but not having any succes..

about the progressive and interlaced piece.. convert them seperately to progressive OR interlaced and that should work.. yet there is still that problem of a different framerate.. I'm not sure how to handle that.

[stanwebber]

did you enable rebuild progressive? this will **** up if significant parts of your source are ntsc or hard-telecined

[RevyJay]

I tried both reconstruct and leaving it alone, but neither of them worked. It's like the first part of the movie was perfect, no choppyness what so ever. Then when it hit that interlaced part, the frames seem to be left out. I tried 23.976, I tried 29,976, I even tried the Pal format of 25fps, and nothing. It seems very weird. I've ripped DVD's many times, but none like this. Is their a new form of security function out there that is doing this?

[stanwebber]

i'm still not convinced anything is wrong yet. if you specify the correct field-order & encode 29.976fps it should play back identical to the dvd(unless field-order changes between vobs). does the dvd itself exhibit these problems during playback? how are you evaluating your results? software/hardware player?

[homerpez]

I thought interlace artifacts were invisible at VCD resolutions? (240 vertical)

But it's been a while since I worked with VCD or MPEG-1 for that matter, so I should rightly be questioned.

[stanwebber]

interlace artifacts will be eliminated if you completely discard one of the fields, but i'd guess most people resize/blend which produces light ghosting during motion & abrupt scene changes. you can deinterlace before resizing to eliminate the ghosting, but this coupled with the resize is likely to blur the image more than you'd like

[RevyJay]

See, that's the thing. I know it sounds confusing, but I don't really know how to explain it. I rip the movie with SmartRipper. When it's done, it create an info file that has how many frames were ripped. When you take the length of the movie using 23.976 or 25 fps, the frames are too less, and your video gets cut short. If I use 29.976 fps, then there are too many frames, and the movie is too long. When I watch the preview of the movie in FlaskMPEG, in the middle of the movie, it goes from progressive to interlaced. That's where the frame rate changes. The regular DVD didn't do this. It didn't skip or anything.

[stanwebber]

it's not unusual for the # of encoded frames to be less than the # of frames during playback. it means the source is either hybrid or part of it is soft-telecined & the rest hard-coded telecine. if the former encode 29.97fps; if the latter you still have the option to ivtc

[RevyJay]

What is that, and how do you do that?