[davior]

This finishes M2 of the plan of attack. Renders now draw what the VideoSpec already described but M2a only warned about: on-screen text, lower thirds and pictures. They also carry credits, and a finished render can be filed back into GAM.

Pairs with davior/gam#37 (GAM-3). Merge order doesn't matter. Against a GAM without it, Save to GAM still works, and the file lands as an ordinary upload instead of a "Video Creator" export.

What you can do

• Scenes tab: "On screen" per scene. Add text, a name and role (lower third), or a picture from GAM.
  • Settings: position, size and colour for text; width and opacity for a picture; and a fade.
  • Timing: each one shows for the whole scene unless you choose From and Until. Those can be the scene's start or end, any narration line's start or end, or a later scene, each with an offset in seconds. Reaching into a later scene is how you hold a title through a dissolve.
• Render tab: Credits.
  • "Credit the library's pictures, footage and music" pulls each GAM asset's credit, so you correct a credit once in GAM and every video using it follows.
  • Toggles for "Show them on a card at the end" and "Put them in the description".
  • Extra lines of your own.
• Render list:
  • Save to GAM on a finished full render, then an In GAM ↗ link to it. Saving twice files it once; if it was deleted in GAM, it is filed again.
  • The latest render shows its description (chapters as 0:00 Title lines, then credits) with a Copy button.

How

• Overlays are one extra video pass after the stitch (ffmpeg.build_overlay_pass). Each layer is a full-frame PNG drawn by Pillow, looped, alpha-faded at absolute times, and composited with overlay=…:enable='between(t,a,b)'.
  • Doing it per shot would have kept the shot cache, but couldn't draw across a join.
  • The pass only runs when a video has timed overlays, and it copies the sound.
• compile.place_overlays follows place_tracks:
  • anchors default to the overlay's own scene;
  • fades are held to half the window, so the fade in and fade out never cross;
  • an orphaned or backwards span, or a picture overlay given a non-picture, is dropped with a warning and never fails the render.
• Credits:
  • media.resolve now keeps each asset's GAM credit.
  • credits.credit_lines orders them by first use, says each once, and appends the extra lines.
  • credits_units appends end cards, splitting past 18 lines.
  • The estimate counts the card.
• Save to GAM:
  • POST /api/renders/{id}/save-to-gam streams the file as the requester, sending source=gvc_export, origin_project_id and origin_reference_id.
  • It then names the asset "Title (vN)" and sets the description through GAM's PATCH.
  • Previews are refused: they are 480p working copies.
• Migration: render_job.description and render_job.gam_asset_id, run by the entrypoint as usual.
• Refactor: the scene-or-line anchor picker is now shared (AnchorSelect, spec/anchors.ts) between the Soundtrack tab and overlays.

Tests

• Backend: pytest -q passes, 459 tests. New ones include:
  • Real-ffmpeg pixel checks:
    • a text overlay is dark before 1.0 s, drawn at 2.0 s, still drawn inside the dissolve and 1.2 s into the next scene, and gone after;
    • a lower third shows only between 0.5 s and 2.0 s.
  • Credits in a real render: the end card adds its length, and the description lists the chapters and the credits, with a credit two assets share appearing once.
  • Compiler: default spans, own-scene and beat anchors, reaching into the next scene, fade clamping, orphaned and backwards spans, and a picture overlay without a picture.
  • Credit lines and cards: ordering and de-duplication, card splitting, the description format, and the overlay-pass argv.
  • Save to GAM: the token and form fields forwarded, naming and description, idempotency, re-filing after a GAM delete, refusing previews and unfinished renders, and the owner check.
• Migration: upgrade, downgrade and upgrade again on a fresh database.
• Frontend: format, lint, npm test (98 tests) and build pass. New tests cover the overlay helpers, the anchor value round-trip, the editor timing a lower third to a line and a later scene, credits on and off, and Save to GAM to the In GAM link.
• Checked by eye: a lower third with a text overlay, and a credits card, drawn at 720p.

🤖 Generated with Claude Code

https://claude.ai/code/session_016fiRJAt34ag62iPiuMkNhm

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Generated by Claude Code