Command Chaining

Run multiple FFmpeg commands sequentially on the same machine. This is efficient for multi-step pipelines as intermediate files stay local.

When to Use This

Use command chaining when a later command needs a file made by an earlier command.

Common uses:

• Create an intermediate encode, then package it.
• Extract frames, then encode a preview.
• Make many outputs from one downloaded input.

Example

{
  "input_files": { "raw": "https://example.com/large.mov" },
  "output_files": ["final.mp4"],
  "ffmpeg_commands": [
    "-i {{raw}} -vf scale=1920:1080 temp.mp4",
    "-i temp.mp4 -c:v libx264 -crf 23 {{final.mp4}}"
  ]
}

Each command in the ffmpeg_commands array runs in order. Files produced by an earlier command, like temp.mp4, can be referenced by later commands.

Output Files

Only list files you want returned in output_files.

Intermediate files can be used in later commands without being listed as outputs.

{
  "output_files": ["final.mp4"],
  "ffmpeg_commands": [
    "-i {{raw}} -vf scale=1920:1080 temp.mp4",
    "-i temp.mp4 -c:v libx264 {{final.mp4}}"
  ]
}

Notes

• Commands stop at the first failure.
• All commands run on the same worker.
• Intermediate files are not uploaded unless they are listed in output_files.