Remotion motion graphics

Remotion Motion Graphics

Remotion renders React components frame-by-frame into video. Code quality is not the bottleneck — motion design craft is. Untrained generation produces linear easing, opacity-only fades, simultaneous entrances, flat colors, and no texture. That is the "generic AI video" look. This skill exists to prevent it.

Non-negotiable rules (apply to EVERY composition)

1. NEVER use linear interpolation. Every interpolate() gets an easing curve; every entrance prefers spring(). Always extrapolateLeft/Right: "clamp".
2. Entrances animate 2–3 properties together (opacity + translateY + scale). A lone fade is forbidden.
3. Stagger everything. Lists, words, rays, cards: 3–6 frame offsets. Nothing enters simultaneously.
4. Exits exist and are faster than entrances (~10 frames vs ~20).
5. Five-layer stack in every scene, bottom to top: background mesh → assets → graphics/type → color grade → grain + vignette. Never a flat solid background.
6. Every still image gets Ken Burns (slow scale 1→1.08 + pan). Every video asset uses <OffthreadVideo>, never <Video>.
7. Idle elements breathe: anything on screen >2s gets sin-wave micro-motion.
8. All timing derives from fps via useVideoConfig(). No magic frame numbers.
9. One theme object at the top of the project (colors, easings, spring presets, fonts). Never inline a hex color or easing in a component.
10. Render, extract frames, LOOK at them, fix, re-render. Never deliver an unverified render. This loop is mandatory — see Verification below.

Workflow

Step 1 — Scope

Determine: duration, fps (30 default; 60 only for heavy fast motion), dimensions (1080×1920 Reels/Shorts, 1920×1080 landscape), what assets exist (images, footage, audio, logos), and whether this is a new composition or an edit to an existing project. If editing an existing project: read src/ fully first, find the theme (or create one), and refactor violations of the rules above before adding features.

Step 2 — Setup

New project:

npm install remotion @remotion/cli react react-dom
# optional: @remotion/transitions @remotion/motion-blur @remotion/google-fonts

Copy assets/theme.ts from this skill into src/theme.ts and adjust the palette to the user's brand. Structure: src/index.ts (registerRoot) → src/Root.tsx (Composition, duration/fps/size) → src/scenes/*.tsx → src/components/*.tsx. User assets go in public/, loaded via staticFile().

Step 3 — Build

Read references/motion-patterns.md for the reusable component implementations (BgMesh, Grade, Grain, Vignette, KenBurns, WordReveal, Stagger, Counter, Spark, transitions, parallax). Compose scenes from those patterns. For pacing, rhythm, typography, color palettes, and sound design rules, read references/design-rules.md.

Scene rhythm: HIT → hold (15–20 still frames) → build → HIT. Something must move in the first 15 frames. Never >90 frames without a new visual element.

Step 4 — Render

npx remotion render src/index.ts <CompId> out/video.mp4 --codec h264 --crf 17

Remotion needs a Chromium binary. If its auto-download fails (sandboxes, offline CI), find one and pass it explicitly:

which chromium chromium-browser google-chrome 2>/dev/null
ls /opt/pw-browsers 2>/dev/null   # Playwright installs live here
npx remotion render ... --browser-executable=<path>

If full Chrome errors with "Old Headless mode has been removed", use a headless_shell binary instead (Playwright ships one as chromium_headless_shell-*/chrome-linux/headless_shell).

Step 5 — VERIFY (mandatory, never skip)

Extract frames at key moments and visually inspect each one:

ffmpeg -v error -i out/video.mp4 -vf "select='eq(n\,15)+eq(n\,45)+eq(n\,90)+eq(n\,N-10)'" \
  -vsync 0 check_%d.png

Look for, and fix, in order of frequency:

• Spacing bugs: gap/margin in em resolves against the PARENT font-size (often 16px), not the text size — use px values in flex containers around big type.
• Text overflowing or touching frame edges (keep critical content in middle 75% vertically for 9:16 — platform UI covers top/bottom).
• Elements visible before their entrance or after their exit (missing clamp).
• Color/contrast failures: hero color on >1 element per frame, dim text unreadable over the grade.
• Layer order mistakes (grain/vignette must be on top, grade above content). Fix → re-render → re-extract → re-inspect. Only deliver after a clean pass. Then run the final checklist at the bottom of references/design-rules.md.

Editing the user's existing footage

To enhance an existing mp4 (captions, grade, intro/outro) rather than build from scratch: put the file in public/, render it as the asset layer with <OffthreadVideo src={staticFile("clip.mp4")} />, set composition duration from the clip length, and stack graphics/grade/grain above it. Get the clip's duration and fps with ffprobe before setting up the composition. For word-synced captions over speech, see the captions section of references/motion-patterns.md.

Reference files

• references/motion-patterns.md — copy-paste component library: backgrounds, grade/grain/vignette, Ken Burns, text reveals, counters, transitions, parallax, audio sync, captions. Read before writing components.
• references/design-rules.md — palettes, typography rules, scene architecture, sound design, pre-delivery checklist. Read before designing scenes and before final delivery.
• assets/theme.ts — the theme template to copy into every project.

Common failure modes to actively avoid

• Generating one giant component instead of themed, reusable pieces.
• durationInFrames mismatch between Composition and scene content (dead air).
• Forgetting --overwrite on re-renders, then inspecting the stale file.
• Fonts: never rely on system defaults for hero text; load a display font via @remotion/google-fonts or @font-face + staticFile.
• Trying to "describe" the result to the user instead of rendering and verifying it.