`AudioPool::load_from_serialized` sizes the slot Vec by pool_index and fills gaps
with empty `AudioFile::new(PathBuf::new(), …)` placeholders. Two bugs let a
placeholder reach the next save and abort it with "Is a directory":
- Off-by-one: `entries.max().unwrap_or(0) + 1` made an *empty* pool length 1, so a
project with no audio still got one placeholder. Size by `max(pool_index + 1)`
→ empty entries yield length 0.
- `serialize()` emitted placeholder slots: an empty path round-trips to
`relative_path = Some("")`, which `save_beam` resolves to the project directory
(`join("")`) and tries to read as media. Skip empty-path / no-packed-media slots.
- Defense in `save_beam`: gate referenced-media packing on `full.is_file()` (not
`exists()`), so any blank/dir path falls through to embedded data instead of
reading a directory.
Pre-existing; surfaced by a save → reload → save cycle on a raster-only project.
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.
Migrate the .beam container to SQLite and stream media from it instead of
decoding whole files into RAM on import/load.
Container & large files:
- SQLite .beam container (beam_archive) with in-place transactional saves and an
incremental BlobReader; supports both packed (chunked blobs) and referenced
(external path) media, with a user preference + first-import prompt for files
over the large-media threshold.
Audio streaming:
- Stream packed compressed audio on load via an inversion-of-control blob factory
(AudioBlobSourceFactory): daw-backend defines the trait, core implements it
over BlobReader, so the audio engine stays container-agnostic.
- Bulk-activate disk streaming for all loaded clips after SetProject.
- Sample-accurate compressed seek (SeekMode::Accurate; Coarse mislands on VBR).
Video:
- Video frames decoded/streamed on demand; thumbnails generated asynchronously
on a dedicated decoder so import/load never blocks the UI.
- The video's audio track is streamed on demand via an ffmpeg VideoAudioReader
as a separate editable AudioClip (no /tmp WAV extraction).
Waveform overview:
- Streaming min/max LOD pyramid (waveform_pyramid), bounded memory, configurable
floor B; serialized into the container and restored on load (or generated in
the background from the packed blob when absent), so no re-decode on reload.
- GPU min/max upload path; integer-LOD textureLoad fixes zoom-dependent wobble.
Skyler Lehmkuhl