After the demuxer → filter switch, concat still failed with
[fc#0] Error sending frames to consumers: Invalid argument
on Job 8. The filter graph normalised pixels (scale+pad+yuv420p) but
left the time-domain axes mixed:
segment-1: 23.98 fps video, 44100 Hz audio
segment-2: 60 fps video, 48000 Hz audio
segment-3: …
ffmpeg 8's concat filter requires identical frame rate + audio sample
rate + channel layout across inputs. Force them on each leg:
video: fps=<seqFps>, setpts=PTS-STARTPTS
audio: aresample=48000,
aformat=channel_layouts=stereo:sample_fmts=fltp,
asetpts=PTS-STARTPTS
setpts/asetpts re-zero each input's clock so concat's per-input PTS
window resets cleanly between segments.
Target fps comes from the sequence's frame_rate (rounded) — same axis
the sequence editor stores. Sample rate is pinned to 48000 (broadcast
standard) so the AAC encode is consistent.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
fcf4c8bbe7