The rebuild after 1457556 came out byte-identical to the broken file,
which proved the xfade fix never runs for this chapter. An all-cut chapter
goes down the concat demuxer with -c copy, which writes the output in the
FIRST input's time_base and reinterprets every later packet in it. 14 of
49 clips are 30/1 at 1/15360 against 35 at 25/1 at 1/12800, so those 14
play 15360/12800 = 1.2 too long with their audio untouched. collage_cmd
hardcoded -r 30 and yesterday's FPS sweep missed it.
collage_cmd now emits -r FPS, and assemble probes r_frame_rate across the
clips and routes mixed rates through the re-encoding tree. Rebuilt
chapter.mp4 is 364.120s video against 364.122s audio at 25/1, from
436.392 over 363.675.
Also settle the bbox coordinate space, measured over all 113 detections:
47 boxes have x2 past the 900px panel width, none has y2 past 1000 on
panels up to 2307px tall, and the range is exactly [0, 1000]. It is
gemma's normalized grid, not pixels, whatever the prompt asks for.
/vision converts before returning, which fixes identity's crop, the gated
face pairing that was comparing pixel face boxes against grid boxes, the
set-of-mark boxes and the review UI at once. Checked by eye on panel 7:
five of six boxes now land on their subject, including the foreground
character who had no identity.
The registry still holds boxes and embeddings enrolled from the wrong
space. vision and identity have to re-run, which is GPU work and was not
started.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
_xfade_chain positioned every transition using _audio_dur, which probes
format=duration, which is max(video, audio). A clip's audio outlasts its
video by about a frame, so the offset accumulator crept ahead of the real
picture timeline. Once the creep exceeded the transition width, xfade
emitted the transition and silently discarded the second input and every
clip downstream, exiting 0 with nothing on stderr. That is the whole of
the shipped chapter's 436.39s of video over 363.67s of audio.
Offsets now come from min(video, audio). Every input is floored to a
whole frame count and trimmed on both streams, so the accumulator tracks
the real timeline instead of estimating it. _check_assembled verifies
each encode against the predicted length and against its own audio,
because both assembly branches drop stream time without failing.
Verified over the 49 real clips of chapter 7c944dd4: the round that
turned 359s of video into 100s now loses 0.85s, and the chapter comes out
358.76s video against 358.76s audio.
The single-item passthrough was not the cause. Two round-0 groups of 8
fresh clips collapse without one, recorded void in decisions/.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
kami