[FFmpeg-user] How to decrypt .ts files into separate .ts files with ffmpeg without using a playlist?

Ted Park kumowoon1025 at gmail.com
Fri Feb 14 17:36:06 EET 2020

> No, I didn't change the ts segments or m3u8 at all, they all were downloaded straight from the source.
>> Are the issues on frames 59, 119, 179, 239, 299?
> Well, I'm not quite sure how to check this so precisely to be honest :-(

I can only guess at this point, perhaps it resulted from the conversion from a 59.94 ntsc source to progressive. I was only able to figure out the issue you mentioned by forcing -vsync 0. If I don’t include that option (to preserve original timestamps) the issue disappears. I used this command:
% ffmpeg -i test.ts -f image2 -vsync 0 -copyts -frame_pts true %d.png
To inspect the frames and it doesn’t look like any were dropped or duplicated while muxing at least.

There are also no frame drops when playing back the plain concatenated .ts file; the frame drops when playing back the file muxed using the hls muxer and playlist seem to be an A/V sync issue, adding -sync video when playing with ffplay seems to eliminate them (though I suspect it might cause audio drift with a longer file). I think this is due to the fact that not both the video and audio in each segment is 4.004 seconds long.

At this point I would take all the information gathered/guessed and decide what the best option would be depending on what you are ultimately trying to do.

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