Surround → stereo downmix:
- render_from_file folds multichannel sources (5.1/7.1/…) down to stereo with
proper coefficients (full level for the matching front channel, 1/√2 for centre
+ each surround, LFE dropped), normalized per row to avoid clipping (matching
ffmpeg's default). Applied uniformly to both the direct-copy and sinc-resample
paths and to every storage type (PCM, compressed, video audio), only when
dst==2 && src>2; unknown layouts fall back to front L/R. Previously it just took
FL/FR, dropping centre dialog + surrounds.
Proper video-audio reload:
- A video's audio track is now stored as a path reference to the video (never
packed/embedded as audio media) and re-probed via FFmpeg on load into a
streaming VideoAudio entry, so multichannel audio survives reload (the old
Symphonia reconstitution collapsed it, breaking the downmix). Driven by a new
AudioPoolEntry.is_video_audio flag across serialize / save_beam / load. Also
removes the decode-whole-video-to-RAM + temp-file path on load.
Fix video scaling:
- Any video with dimensions larger than the stage was being scaled down into the corner incorrectly; we now bake the frame-clip scale into the instance transform.
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