Experimental, with clear limits.
Experimental · not reviewed by a BdSL signer.
SignBridge pairs source-video segments and held frames with sequences assembled from corpus assets. It shows missing critical concepts before signing and saves version-bound tracks that can be reopened without another model call. Rendering a sequence does not establish correct BdSL or comprehension.
Three separate evidence categories
Technical renderability
20 of 20 sampled corpus files were technically render-probed on one Windows host in headless Edge with software WebGL (Phase 2). Phase 5 also played a five-unit, cross-file fixture through the application frame on headless Chromium and Edge. These are laboratory rendering observations, not mobile-hardware results or language assessment.
Linguistic correctness
None. No qualified BdSL signer has judged a specific rendered version acceptable.
User comprehension
None. Deaf/BdSL users have not evaluated the content in a comprehension study.
Limits you can see
Newly composed sequences are experimental. Missing negation, quantities, actors or other critical concepts can change the meaning, so incomplete segments show a blocking card and never count as fully signed. A timeout, missing unit or Skip also never counts as completion. Source confirmation means the creator checked the caption text; it is separate from linguistic review.
The unmodified University of East Anglia renderer remains a remote dependency at replay time. WebGL is required. If it is unavailable, saved captions, transcript and gap markers remain readable. Only the sampled, successfully probed assets are currently eligible; the remaining corpus is not represented as supported vocabulary.
Personal data, sharing and retention
Caption text, context and clip title are sent to OpenAI when real processing is enabled. They may contain names, places, opinions or other personal data. Requests use store: false; this is not a claim that no personal data is sent or that the provider has no retention. Local development uses an explicitly labelled deterministic fake model. Upload only content you have permission to use.
Projects are private until their creator enables an unlisted, view-only link. Anyone holding that link can view the transcript, source video and saved track. Revocation blocks future authorized reads; already issued source-video URLs may remain valid for up to 15 minutes.
Non-pinned videos expire after 72 hours. Cleanup targets 96 hours when reconciliation runs at least daily; scheduling delays or service outages can delay physical removal. Pinned demo media is excluded. Deletion hides the project and revokes sharing immediately; physical purge waits for existing upload URLs to expire and reconciliation to finish. Billing history remains for budget accounting; orphan stage results expire after 30 days and render telemetry after 14 days.
Attribution
Sign data: IsharaKotha v2, DOI 10.17632/6ykgx65ks5.2, CC BY 4.0. Authors: MD. Ashikul Islam; Prato Dewan; Md Fuadul Islam; Md Ataullha Saim; M Shahidur Rahman.
Gloss identifiers are rewritten to lowercase ASCII and sign units are assembled into playback documents. Imported motion content is retained apart from identifier changes. Unsafe or malformed assets are quarantined, rather than silently repaired.
Avatar rendering: UEA CWASA vhg2026, standard Anna avatar, used remotely and unmodified under UEA’s conditions of use. Engine code and avatars are not redistributed. SignBridge does not claim to have invented video-to-avatar or text-to-avatar rendering; earlier work includes SignOLight and IsharaKotha research.
The organizer-supplied official event sticker is displayed in the top banner. The original image is used unchanged.