{
  "asset_id": "mermaid_wild",
  "tool": "Seedance via Anijam (ByteDance)",
  "tool_version": "1.x",
  "model_native_resolution": "1440x1440",
  "model_native_fps": 24,
  "source_image": "../../sources/mermaid_wild__source.png",
  "prompt_used": "../../prompts/RICA_ANIME_PROMPT_v3.md",
  "prompt_iteration": "v4 (chroma green BG hardcoded at top of prompt)",
  "date_utc": "2026-05-16",
  "duration_seconds": 5,
  "background_color_intended": "neon green #00FF00 chroma key",
  "background_color_actual": "dark green RGB(~10,50,30) — model rendered green-dominant but darker than #00FF00, still chroma-key extractable",
  "chroma_key_method": "ffmpeg chromahold + colorkey 0x0a3a1e + despill type=green mix=0.2 (REFINED, was 0.7 too aggressive)",
  "transparent_output_HEVC": "seedance_v4_30fps_TRANSPARENT_hevc_REFINED.mov (HEVC alpha yuva420p, Safari/iOS friendly)",
  "transparent_output_WEBM": "seedance_v4_30fps_TRANSPARENT_REFINED.webm (VP9 alpha)",
  "outputs": {
    "native_24fps.mp4": "raw Seedance output (dark green BG)",
    "30fps_mci.mp4": "ffmpeg 24→30 motion-compensated interpolation",
    "60fps_mci.mp4": "ffmpeg 24→60",
    "30fps_loop_pingpong.mp4": "forward+reverse seamless 10s loop",
    "30fps_TRANSPARENT_hevc.mov": "v1 alpha (despill too aggressive — blue tint)",
    "30fps_TRANSPARENT_hevc_REFINED.mov": "v2 refined alpha (despill 0.2, original colors preserved)",
    "30fps_TRANSPARENT.webm": "VP9 alpha v1",
    "30fps_TRANSPARENT_REFINED.webm": "VP9 alpha v2 refined",
    "alpha_sample/frame_alpha_t2.5s.png": "PNG mid-frame proof — A=0 transparent borders confirmed"
  },
  "verification": "Alpha confirmed: PNG sample shows corner pixels with A=0 (transparent) and center with A=255 (opaque)",
  "user_feedback": "Major improvement vs v3 black BG. Chroma extraction works clean now."
}