When I used ffmpeg's concat demuxer to join the clips above I get significant video and audio artifacts on playback. However, I would like there to be smooth transitions between these segments, so I have further split these segments so that the short ends can be used to create a crossfade transition without re-encoding the entire set of files.Ī basic diagram would probably help illustrate this: | (original file) If I use the concat demuxer at this point, the different parts get joined together perfectly- so far so good! Using -ss as input option together with -c:v copy might not be accurate since ffmpeg is forced to only use/split on i-frames.Īs it happens, the splits aren't happening at exactly the right moment, but are close enough for the moment that I can focus on another part of the equation. I have written a python script to find the nearest keyframe to the desired cut point, and cut there, since when doing a stream copy ffmpeg can only use I-frames: I have a file I would like to cut and keep useful parts from. (emphasis mine) My intention 1 is to produce media files with the same codec and parameters so that I can take advantage of concat without incurring a long re-encode. If you have media files with exactly the same codec and codec parameters you can concatenate them 5.2.Ffmpeg can be used to concatenate files together: Users can skip – map and let ffmpeg handle stream selection. It also sets the number of output audio streams.įinally, the -map flag in step 5 allows for a custom stream selection in each output file if there are multiple. Similarly, a (default is 0) sets the number of audio streams in each section. Next, we follow with v (default is 1), which sets the number of output video streams. In step 4, the number of files we want to join is in the value of n (default is 2). Map the resulting audio and video streams to the output.Select the actual streams in a specific order: video and audio from the first, second, and third file.Use -filter_complex to select streams from the input files.Here’s a quick rundown of what’s going on in the command: To explain the contact filter, we’ll use start.mkv, body.mkv, and rear.mkv with a single audio stream: $ ffmpeg -i start.mkv -i body.mkv -i rear.mkv -filter_complex \
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