Remove duplicate frames from 30FPS video

[midts]

Hi everyone. I purchased this digital video and it's full of duplicate frames and it's very visible when watching it on TV, because it's HD 720p quality. At first I thought it's every 5th frame so I used:

tfm(order=1).tdecimate(cycle=5,cycleR=1)

It converted the FPS to 24 and looked like it's fixed, but I found out that there is still some dupe frames (like e.g. at frame 33-34), so not sure what to do at this point.

Thanks everyone for any help!

[jagabo]

Try TDecimate(mode=2, rate=24000.0/1001.0) to get 23.976 fps. You'll need a longer sample though -- because the difference is only one frame in every 1001. You might need to use the m2PA=true argument too. Or mode 7.

[midts]

Hi @jagabo, I tride your suggestion:

tfm(order=1).tdecimate(mode=2, rate=24000.0/1001.0)

and I don't think it changed anything, same duplicate frame.

Edit: I also tried mode=7 and it did convert to 23.976, but the dupe frame still exist.

tfm(order=1).tdecimate(mode=7, rate=24000.0/1001.0, m2pa=true)

Edit2: Added 45 second long sample with 1350 frames on top post.

Edit3: I think I got the correct output with this:

tfm(order=1).tdecimate(mode=2, rate=24000.0/1001.0, m2PA=true)

The every 5th frame are gone and that one annoying frame is also gone. I tested this on the 45s sample.

So what does m2PA=true exactly do? And mode=2 and mode=7?

[LMotlow]

I tried this:

tdecimate(mode=2, rate=24000.0/1001.0, m2PA=true)

I don't think you need TFM. You're matching frames, not fields. Thanks to both for this solution, I had an old British TV film with the same quirky structure. The above routine seems to clean it up.

[jagabo]

First make sure the output of your source filter is really 30 fps. I used LWLibavVideoSource() and it gave 29.995. Be sure to start well before the problem frame, and end well after it -- say a few thousand frames before and after. It may take a while for TDecimate() to sync up.

You might also try:

TDecimate(Cycle=5, CycleR=1) # 30 fps to 24 fps
TDecimate(Cycle=1001, CycleR=1, m2PA=true) # 24 fps to 23.976 fps

As for what mode and m2PA are -- read the docs.

[LMotlow]

This video is an odd critter. Actually I tried it two ways. This came first:

tdecimate(mode=7, rate=24000.0/1001.0, m2pa=true)
TDecimate(Cycle=30,cycleR=1)
AssumeFPS("ntsc_film")

It gave me 23.177 fps, so I added AssumeFPS().

The second way worked and gave me 23.976fps:

tdecimate(mode=2, rate=24000.0/1001.0, m2PA=true)

[midts]

This video is an odd critter. Actually I tried it two ways. This came first:

tdecimate(mode=7, rate=24000.0/1001.0, m2pa=true)
TDecimate(Cycle=30,cycleR=1)
AssumeFPS("ntsc_film")

It gave me 23.177 fps, so I added AssumeFPS().

The second way worked and gave me 23.976fps:

tdecimate(mode=2, rate=24000.0/1001.0, m2PA=true)

Are you talking about my sample or your British TV film?

[LMotlow]

Both. The Brit film was recorded about 3 months ago on an HD PVR. Same structure. Handy coincidence.

[EDIT] 'Scuse me, it wasn't British. Australian, broadcast on PBS.