skills/analyze-any-video/scripts/extract-video-evidence.sh

#!/bin/sh
set -eu

usage() {
  echo "Usage: $0 INPUT_VIDEO OUTPUT_DIR [INTERVAL_SECONDS]" >&2
}

if [ "${1:-}" = "--help" ] || [ "${1:-}" = "-h" ]; then
  usage
  exit 0
fi

if [ "$#" -lt 2 ] || [ "$#" -gt 3 ]; then
  usage
  exit 2
fi

input_video=$1
output_dir=$2
interval_seconds=${3:-5}

if [ ! -f "$input_video" ]; then
  echo "Input video not found: $input_video" >&2
  exit 3
fi

case "$interval_seconds" in
  ''|*[!0-9.]*|.*|*.) echo "Interval must be a positive number." >&2; exit 4 ;;
esac

if ! command -v ffmpeg >/dev/null 2>&1 || ! command -v ffprobe >/dev/null 2>&1; then
  echo "ffmpeg and ffprobe are required but were not found." >&2
  exit 5
fi

mkdir -p "$output_dir/frames-interval" "$output_dir/frames-scenes"

ffprobe -v error -show_format -show_streams -of json "$input_video" > "$output_dir/metadata.json"
ffmpeg -hide_banner -loglevel error -i "$input_video" -map 0:a:0? -ac 1 -ar 16000 -c:a pcm_s16le "$output_dir/audio-analysis.wav"
ffmpeg -hide_banner -loglevel error -i "$input_video" -vf "fps=1/$interval_seconds,scale='min(1280,iw)':-2" -q:v 2 "$output_dir/frames-interval/frame-%06d.jpg"
ffmpeg -hide_banner -loglevel error -i "$input_video" -vf "select='gt(scene,0.30)',scale='min(1280,iw)':-2,showinfo" -vsync vfr -q:v 2 "$output_dir/frames-scenes/scene-%06d.jpg" 2> "$output_dir/scene-log.txt"

{
  echo "source=$input_video"
  echo "interval_seconds=$interval_seconds"
  echo "metadata=$output_dir/metadata.json"
  echo "audio=$output_dir/audio-analysis.wav"
  echo "interval_frames=$output_dir/frames-interval"
  echo "scene_frames=$output_dir/frames-scenes"
  echo "scene_log=$output_dir/scene-log.txt"
} > "$output_dir/manifest.txt"

echo "$output_dir/manifest.txt"