18 lines
665 B
Bash
18 lines
665 B
Bash
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#!/usr/bin/env bash
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# Extract a clip to a PNG sequence for the take builder.
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#
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# Frames are pre-extracted rather than decoded in the page on purpose: browser
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# video seeking by currentTime is approximate and requestVideoFrameCallback only
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# delivers frames at playback speed, so neither gives a deterministic per-frame
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# pass. A PNG sequence is exact, instantly seekable, and reproducible.
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set -euo pipefail
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src="${1:?usage: ./extract.sh CLIP [FPS] [OUTDIR]}"
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fps="${2:-24}"
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out="${3:-frames}"
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rm -rf "$out"
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mkdir -p "$out"
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ffmpeg -hide_banner -loglevel warning -i "$src" -vf "fps=$fps" "$out/%04d.png"
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echo "$(ls -1 "$out" | wc -l) frames at ${fps}fps -> $out/"
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