Known limitations (1.0 programme)

Concise user-facing limits for TranscriptX 0.9.x → 1.0. Deeper audit rows live in developer docs; this page is the single public summary. Do not duplicate claims elsewhere — link here.

Experimental analyses

Some modules are experimental classifiers or heuristics (notably contextual emotion and fine-grained emotion). They are kept off Balanced defaults; opt in via Thorough / Custom presets if you want them. Outputs are not definitive affect labels.

Optional BERTopic and compiled dependencies

BERTopic requires the optional [bertopic] (or [full]) stack (bertopic / hdbscan / umap-learn). Core installs deliberately omit that stack so clean installs are not blocked by umap-learn → numba → llvmlite source builds on some hosts (especially certain macOS arm64 environments without usable wheels).

Without the extra, the module stays listed and runs report a stable missing_extra:bertopic / broken_extra:bertopic skip — the pipeline continues. Docker / requirements.txt images still ship the fuller stack where the image build succeeds.

See bertopic_optional_module.md and the install verification matrix.

Large library / performance measurements

Documented corpus sizes and a measurement recipe ship in developer performance envelopes. Large-library UI soak passed on maintainer hardware (2026-08-07): UI remained responsive with 200+ library transcripts. Medium-corpus Balanced batch also measured 2026-08-07 (~9.3 min wall for 6 transcripts on Docker Compose; all succeeded) — see performance_envelopes_1_0.md and manual_acceptance_1_0.md §3.12.

Voice identity privacy

Voice fingerprint / speaker-match features are identity-sensitive. Read the in-app voice privacy notice before enabling. Local processing does not remove the sensitivity of biometric-like embeddings stored on disk.

Optional auto-name / auto-link on ingest writes display names and may create auto_identified profile links when fusion is confident. It does not enrol new voice samples. Thresholds remain provisional; conflicts and collisions leave SPEAKER_* labels. Style-only apply is off by default. Operator guide: auto-identify.md.

Stochastic Local AI output

Optional Ollama / Local AI modules are stochastic. Re-runs can differ. Artifacts carry model identity fields where available; treat Local AI text as assistive, not ground truth. Principal surfaces label Local AI vs deterministic summaries.

Overview export EPUB

Full behaviour: runtime/export.md.

Overview artifact ZIP export writes index.epub beside index.html when the optional ebooklib dependency is available (pip install -e '.[visualization]' or .[full]; also in Docker / requirements.txt images). Content is selection-scoped — the same artifacts copied into the ZIP that feed the HTML index — not a silent full-run book.

Static chart rasters (PNG/JPEG/WebP/GIF) are embedded when valid; interactive HTML charts appear as captions/notes only (e-readers cannot run them). Generated index.html / index.epub files are exempt from the ZIP source hard-cap and are excluded from feeding subsequent export resolvers if re-selected.

Charts-only ZIP export remains HTML-only (no EPUB) in this release.

Speaker ID Components v2 workspace

An experimental Streamlit Components v2 Speaker Identification workspace ships in the transcriptx-workspaces package (installed in Docker images; optional for native GUI). It is default-on when the package is present. Roll back with TX_SPEAKER_ID_WORKSPACE_COMPONENT=0. If the package is missing, Speaker ID falls through to the classic fragment UI automatically. See theme_c_workspaces_ccv2.md.

Install honesty (Mac MPS)

Native Apple MPS is supported-with-caveats, not universally validated for every optional model. Prefer Docker CPU for predictable installs. If MPS initialisation or model execution fails, use TRANSCRIPTX_FORCE_CPU=1 (documented in installation.md). Do not assume every optional model runs reliably on MPS.