Merge videos

Merge multiple media files.

POST /merge
Content-Type: application/json

{
  "fileIds": ["string", "string"],
  "outputFormat": "string"
}

Uses the first file (fileIds[0]) as the base, and swaps it with the results
Haven't tested it properly so I don't know what happens if some of the files are audio
Automatically detects and matches resolution
Preserves aspect ratio with padding
Uses complex filter chain for proper concatenation
Output encoding:
- Video: H.264 (libx264) with fast preset, CRF 22
- Audio: AAC at 192kbps