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MP4Box for concatenating MP4 files

Full Documentation: MP4Box Wiki


  "tool": "mp4box:cat",
  "parameters": {
    "fps": "23.976",
    "flat": "True",
    "inputs": [
    "output_dir": "out",
    "output": "file.mp4"
Parameter Properties Default Type Choice Description
fps required Frame rate. type: float
inputs required [list value] List of MP4 files to concatenate, or single path with wildcard expression: *
output required MP4 output file
flat optional true bool store file with all media data first, non-interleaved. This speeds up writing time when creating new files. By default all imports are performed sequentially, and final interleaving is done at the end; this however requires a temporary file holding original ISOBMF file (if any) and added files before creating the final output. Since this can become quite large, it is possible to add media to a new file without temporary storage, using -flat option, but this disables media interleaving.
output_dir optional Output folder