Phase 5 — Final Assembly
Subtitle styling, optical transitions, AI Match-Cuts, and timeline export.
Phase 5 reviews rendered scene clips, renders burnt-in subtitles, applies optical transitions, generates optional AI Match-Cut bridges, and delivers production files.
1. Status Bar and Scene Review
The assembly dashboard summarizes readiness:
- Global Metrics: Displays ready scene count, active AI transitions, calculated total project duration, and export resolution.
- Scene Cards with Real-time Preview: Playback clips directly in the browser with burnt-in subtitles and optical transitions rendered on the fly.
- Inter-Scene Bridge: Each gap between adjacent scenes contains a MATCH-CUT button to configure an AI camera transition.
2. Code-Rendered Subtitles
Subtitles are generated directly in browser canvas code without altering Google Flow video prompts or degrading image clarity:
| Option | Available Values | Description |
|---|---|---|
| Visibility | HIDDEN (Default) or ACTIVE | Enable or disable burnt-in subtitles. |
| Typography | Inter, Montserrat, Roboto, Oswald, Courier | Clean web font rendering. |
| Text Sizing | Small, Medium (Default), Large | Scaled in pixels relative to 720p or 360p canvas dimensions. |
| Text & Box Colors | Blue, Yellow (Default), Green, Red, Orange, Black | Supports high-contrast opaque bounding boxes. |
| Synchronization | BY PHRASE (Default) or BY WORD | Chunked lines (up to 6 words) or dynamic word-by-word timing. |
3. Optical Transitions (Zero AI Credits)
Optical transitions are deterministic client-side image transformations executed during export requiring zero Flow credits:
| Style | Visual Behavior | Transition Window |
|---|---|---|
| Continuous Stitch (Default) | Subtle 2–2.5% micro-zoom and 12–14% gentle darkening at boundaries | 0.28 s |
| Soft Edges | Smooth gradual darkening (up to 45%) entering and exiting scene | 0.22 s |
| Cinematic Fade | Deep cinematic fade to near-black (up to 85% opacity) | 0.30 s |
| Kinetic Push-In | Forward dynamic scale transition (1.0x to 1.06x) into the cut | 0.38 s |
| Hard Cut | Direct cut with no edge transformation | Instant |
4. AI Match-Cut Transitions
For dynamic narrative shifts, generate an AI-rendered transition clip bridging the end of scene A and the beginning of scene B:
- Boundary Extraction: Displays the exact final frame of scene A and the first frame of scene B.
- SUGGEST MOTION (AI): An intelligent assistant inspects both frames and writes a kinetic camera movement prompt (whip pans, zoom-throughs, continuous tracking).
- Draft and Master Resolutions: Render draft transitions in 360p on Omni 1.1 Flash, then promote to 720p master once approved.
5. Exports, Downloads, and Delivery Packages
Serelius Flow Video exports distinct production assets ready for publishing or NLE editing:
| Action Button | Delivery Asset | Format & Notes |
|---|---|---|
| DOWNLOAD SCENE | Single scene video clip | MP4 with burnt-in captions and optical transitions applied. |
| DOWNLOAD ALL | All scene clips and Match-Cut transitions | Individual MP4 files numbered in chronological sequence. |
| EXPORT JSON | Complete project state | Lightweight JSON backup file. |
| EDL EXPORT | CMX 3600 Edit Decision List | Timeline file for DaVinci Resolve and Adobe Premiere. |
| SUBTITLES & TRANSCRIPT | Subtitle and transcript files | Clean SRT, VTT, and plain text transcript copied or downloaded. |
6. Client-Side Rendering Engine
Video processing executes natively inside your browser:
- Primary Pipeline: Frame-by-frame canvas processing via WebCodecs / MediaBunny, burning captions and transitions while preserving native Google Flow audio tracks without re-compression.
- Fallback Recording: Automatically switches to native MediaRecorder capture if WebCodecs hardware acceleration is unavailable.
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