![]() ![]() However, the results were still not precise, it would lead me to sometimes shorten the video by too few frames, sometimes too many. I would then use Avidemux to count the superfluous frames in the beginning and end of the video, and move the cut points by nFrames * 40 ms inwards. ![]() I tried a two-pass process, in which I would encode the video once with starting the encode slightly earlier than the cut I want, and finishing it slightly after the end I want. ![]() I still wonder at a timestamp like 00:00:00.216, though, because these videos are at 25 fps and 216 is not even a multiple of 40 ms. I assumed that VLC starts the recording immediately, but Avidemux ignores everything until the first I-frame. Then I noticed that for most of these recordings, for the first frame Avidemux actually shows a timestamp that isn't zero (e.g. The drift is different for each file, and can be positive or negative. However, if I put the timestamp of a frame I seeked to (in format HH:MM:SS.mmm) into the FFMPEG parameters, the cut will actually be off by several frames, sometimes over a second. ts files into Avidemux since it allows comfortable frame-by-frame seeking, and displays the timestamp of the current frame in the necessary precision. Here is what I have tried so far: Attempt 1 However, I'm having a difficult time determining the exact, millisecond timestamps I need to pass to FFMPEG's -ss and -to parameters to hit the cutpoints I want precisely. I would like to extract specific clips from these recordings, based on frame-accurate cutpoints. These stream dumps are stored as MPEG-TS files and contain AVC-encoded video with MPEG audio. I have several video recordings from Full HD IPTV channels that I stored using VLC. ![]()
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