Can't re-render video without it outputting the wrong amount of frames

[Rathma]

I have a video that's too long so i'm just re-rendering the first half, and while I'm inputting the same FPS, the total amount of frames come out wrong. It creates duplicate frames throughout so the sequence is like this (1,2,3,4,4,5,6,7,8,8,9, etc.) You can see the original file on top and the re-render below:



Why is this happening?

[manono]

Did you forget to mention the name of the program you're using?

And rather than rerender and degrade the video quality, can't you just cut it in half?

[Rathma]

Did you forget to mention the name of the program you're using?

And rather than rerender and degrade the video quality, can't you just cut it in half?

The first thing I did instead of rerender was to cut it using avidemux, but it had the same problem.

The render above was done using Adobe Premiere Pro.

[manono]

Assuming your cut using AVIDemux didn't reencode, then I don't believe you. They'll both have the same frame pattern. Do you have any video samples of the 2?

[Rathma]

Assuming your cut using AVIDemux didn't reencode, then I don't believe you. They'll both have the same frame pattern. Do you have any video samples of the 2?

Ah, it's the source video that's messed up from the start. I thought by trimming it or re-rendering it was creating that problem. I've seen this happen twice in videos and I don't know why it happens. Did the producer input the wrong framerate from the start and it's just trying to "fill in" missing frames by creating duplicates?

[manono]

Did the producer input the wrong framerate from the start and it's just trying to "fill in" missing frames by creating duplicates?

Perhaps the duplicate frames were purposely added for television broadcast. You can remove the duplicate frames easily enough using AviSynth's TDecimate filter. It's part of the TIVTC package.

[Rathma]

Did the producer input the wrong framerate from the start and it's just trying to "fill in" missing frames by creating duplicates?

Perhaps the duplicate frames were purposely added for television broadcast. You can remove the duplicate frames easily enough using AviSynth's TDecimate filter. It's part of the TIVTC package.

I think I used something very similar to this: decimate in ffmpeg.


Fixed the problem though you have to figure out what the true fps is before you write in the command. My 29.970 video had a true framerate of 23.976fps. Completely wrong! No wonder I was seeing so many duplicate frames.