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FFmpeg Input Recipes

The publisher's preferred fast path is already fragmented MP4 input. You can generate that with ffmpeg by copying compatible AAC-LC, H.264, or HEVC streams and enabling CMAF-style fragmentation flags.

Fragment an Existing MP4

ffmpeg -i input.mp4 \
  -map 0:v -map 0:a \
  -map_metadata -1 \
  -sn -dn \
  -c:v copy \
  -c:a copy \
  -movflags +frag_keyframe+empty_moov+default_base_moof+separate_moof \
  -f mp4 fragmented.mp4

Re-Encode to Compatible H.264 or HEVC

If the source codecs are not already compatible, re-encode instead of copying.

H.264:

ffmpeg -i bbb_sunflower_2160p_60fps_normal.mp4 \
  -map 0:v:0 -map 0:a:0 \
  -map_metadata -1 \
  -sn -dn \
  -c:v libx264 -preset medium -r 30 -g 60 -keyint_min 60 -sc_threshold 0 -bf 0 \
  -c:a aac -b:a 160k -ar 48000 -ac 2 \
  -movflags +frag_keyframe+empty_moov+default_base_moof+separate_moof \
  -f mp4 sunflower-frag.mp4

HEVC:

ffmpeg -i bbb_sunflower_2160p_60fps_normal.mp4 \
  -map 0:v:0 -map 0:a:0 \
  -map_metadata -1 \
  -sn -dn \
  -c:v libx265 -preset medium -r 30 -g 60 -keyint_min 60 -sc_threshold 0 -bf 0 \
  -c:a aac -b:a 160k -ar 48000 -ac 2 \
  -movflags +frag_keyframe+empty_moov+default_base_moof+separate_moof \
  -f mp4 sunflower265-frag.mp4

Practical Notes

  • -map 0:v -map 0:a keeps only video and audio streams, excluding subtitle and other non-A/V tracks
  • -map 0:v:0 -map 0:a:0 uses the first audio stream if multiple exist
  • -sn -dn explicitly disables subtitle and data or text streams
  • -map_metadata -1 drops container-level metadata from the output
  • +frag_keyframe starts a new fragment on keyframes
  • +empty_moov writes initialization metadata up front
  • +default_base_moof and +separate_moof produce a layout that is easier for fragmented-MP4 pipelines to consume
  • omit +separate_moof only if you are sure downstream tooling can parse interleaved multi-track fragments
  • when audio appears in the catalog but no audio media objects are sent, regenerate with +separate_moof
  • for HEVC, prefer streams that are already hvc1-compatible
  • if a source is tagged hev1 but keeps VPS/SPS/PPS only in the init segment, the publisher normalizes the advertised codec and emitted init segment to hvc1
  • if HEVC samples include in-band parameter sets, the publisher preserves hev1
  • if you start from a progressive MP4, this project can remux it internally, but pre-fragmented input is simpler and more efficient

Live Fragmented MP4 Stdin Publishing

For live encoder pipelines, the publisher can consume fragmented MP4 directly from standard input.

This live path expects ffmpeg to emit track-separated fragments, where each moof + mdat pair belongs to a single media track. Use +separate_moof when generating the stream. Without +separate_moof, audio and video may be carried inside the same moof, which is not the intended input layout for the current live parser.

ffmpeg -stream_loop -1 -re -i bbb_sunflower_1080p_30fps_normal.mp4 \
  -map 0:v:0 -map 0:a:0 \
  -c:v libx264 -preset medium -r 30 -g 60 -keyint_min 60 -sc_threshold 0 -bf 0 \
  -c:a aac -b:a 160k -ar 48000 -ac 2 \
  -movflags +frag_keyframe+empty_moov+default_base_moof+separate_moof \
  -f mp4 - | ./build/openmoq-publisher \
    --input - \
    --endpoint moqt://relay.example.com:443/moq \
    --namespace live/demo \
    --timeout 120