POST /v1/audio/speech returned synthetic audio without the AudioSeal
provenance watermark while /generate marked the same text — and the
audit behind #1169 found the same class of gap in five more producers.
EU AI Act Art. 50(2) (applicable 2026-08-02, expressly carved out of
the open-source exemption in Art. 2(12)) makes machine-readable marking
of synthetic audio a provider obligation, so per-door coverage gaps are
compliance bugs.
Root cause: coverage grew call-site-by-call-site (three separate
embed_watermark calls) with nothing forcing a new producer to opt in.
The fix, per the whole-class rule:
* services/watermark.py grows `mark_synthetic(wav, sr, *, context,
force=False)` — THE named chokepoint (delegates to embed_watermark:
pref-gated, no-op without AudioSeal, never raises / degrades to
unmarked) — plus `will_mark()` for cache-key derivation.
* Gaps closed at the tensor stage, before any encoding:
- openai_compat `_run_tts` (the reported gap; all response_formats)
- tts_stream /ws/tts (per-sentence, before PCM16 framing)
- generation stream=true preview chunks (marked streamed copy; the
saved take keeps its single whole-take mark in finalize)
- batch dub pipeline (assembled track, before WAV write / aac mux)
- longform chapter render — covers /audiobook, /longform/render
(Stories), /audiobook/preview and /audiobook/resume; the chapter
cache key now carries a watermark tag so stale unmarked cache
entries can never be served for a marked-on render
- dub preview-segment (docstring had declared it exempt)
- archetype render (served preview + materialized profile reference)
* Already-covered paths (generate finalize, dub segments, persona
bundles) migrated onto the same chokepoint.
* Documented non-producers/gaps instead of fake coverage:
/stories/encode is a pure transcoder of user uploads (must NOT mark);
the opt-in SoniTranslate sidecar synthesizes+muxes externally and is
a documented provenance gap at its route.
* Regression tests: tests/test_synthetic_audio_watermark_1169.py runs
detect_watermark() on the actual response audio of every producing
route (real watermark service, fake AudioSeal nets, fake engine;
verified fail-before on the pre-fix tree — 11 of 13 fail).
* Recurrence-proofing: tests/test_watermark_route_coverage.py
structurally asserts every synthesis call site references
mark_synthetic (justified allowlist), producers keep their call,
and embed_watermark is never called outside the chokepoint.
Settings toggle semantics are unchanged (the issue's two legal
questions stay flagged for a lawyer, deliberately unanswered here).
Adds a content-addressed segment cache (segment_cache_key + SegmentCache,
cache_dir/segments/) under the existing chapter cache: a changed chapter now
reuses every untouched span's WAV and synthesizes only the edited/missing
ones, and an interrupted chapter render resumes from the segments that already
finished (each persists the moment it renders). The chapter key derivation is
unchanged so on-disk caches from released versions keep hitting, a fully-
unchanged chapter never touches segment files, and prune_cache_dir now walks
both layers so one byte cap bounds the whole cache. Chapter SSE events gain
additive segments/cached_segments counts.
Co-authored-by: mergetest <test@local>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* fix(longform): correctness + robustness fixes from adversarial review
Fixes the confirmed findings from a multi-agent review of the convergence:
HIGH (correctness/output):
- MP3 + cover produced a corrupt file (-map 2:v -c:v copy is invalid for mp3).
Cover art is now embedded for M4B only; mp3 skips it (m4b is the cover format).
- Chapter cache key omitted ref_text — editing only a profile's ref_text served
stale audio. ref_text is now part of the voice signature.
- Preview wrote audiobook_cache/ but the render reads longform_cache/ (rename
missed in PR 5) → cache-warming silently broke. Unified to longform_cache/.
Robustness (DoS/OOM guards):
- /audiobook/import caps upload at 64 MB; epub_to_chapter_script bounds per-entry
(25 MB) and cumulative (300 MB) uncompressed reads (zip-bomb guard).
- /longform/render rejects > 10,000 chapters (422).
Frontend leaks:
- StoriesEditor.removeTrack revokes the line's preview blob URL.
- AudiobookTab revokes the cover blob URL on replace/unmount.
Deferred fast-follows (also from review): render-cache disk eviction; restoring
the standalone chapter cue-sheet export (needs chapter times in the done event).
Tests: mp3-drops-cover, epub entry/total caps, import + chapter-count limits;
updated the cache-hit test for the 4-field voice sig. 70 backend + 334 frontend green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* test(longform): pass EPUB caps as params, not monkeypatch (CI import-path fix)
The cap tests monkeypatched module constants, but in the full-suite CI context
the module loads under a different import path so the patch missed the function
(it used the real 300 MB cap → tests failed). epub_to_chapter_script now takes
max_entry_bytes/max_total_bytes kwargs (default to the constants); tests pass
small values directly — deterministic regardless of import path.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* feat(audiobook): per-chapter preview + resume + chapter fault-isolation (PR 3/8)
Builds on the shared core (#408) and metadata UI (#409). Chapter-level control,
the spec's PR 3.
Shared core:
- chapter_cache_key(spans, sr, engine_id, voice_sig) — deterministic content
hash of a chapter's audio inputs. Same inputs → reuse; any change (text,
voice, order, pauses, sr, engine, resolved-voice signature) → re-render.
Backend (audiobook router):
- Chapter WAVs are now content-addressed in OUTPUTS_DIR/audiobook_cache. A
re-run after a failure/interruption reuses already-rendered chapters and only
synthesizes the missing/changed ones (resume). Job emits `cached` per chapter
and `cached_chapters`/`failed_chapters` on done.
- Per-chapter fault isolation: a chapter that throws emits `chapter_error` and
the job continues; the m4b assembles from the successful chapters. Re-running
retries only the failed (un-cached) chapters.
- POST /audiobook/preview — render a single chapter to audition it; shares the
same cache so a preview warms the full run and a re-preview is instant.
- _build_synth now exposes resolve + engine_id; _prepare_synth unifies the
omnivoice/generic paths for both the job and preview.
Frontend:
- Plan view: a ▶ preview button per chapter with inline playback.
- Done panel: "reused N chapters" + "N failed — click Create to retry" notes.
Tests: chapter_cache_key determinism + sensitivity (8); preview validation +
cache-hit-skips-synth (3). 55 backend + 326 frontend green; build clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
* fix(audiobook): mark cache-key SHA1 usedforsecurity=False (bandit B324)
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
debpalash