graphic-overlays

Graphic Overlays

Graphic Overlays takes a local video that plays in full and layers a sequence of timed, designed graphic cards onto it — titles, lower-thirds, data callouts, quotes, side panels, picture-in-picture — synced to what's being said. The agent designs the cards (timing + content) and writes each card's HTML directly in the conversation, then assembles a single composition HTML and renders it to MP4 via hyperframes. There is no fixed archetype list and no prescribed card structure — the overlays emerge from what the transcript actually says.

> Confirm the route before you build. This skill packages an existing talking-head clip with designed graphic cards (titles, lower-thirds, data callouts, quotes, side panels, PiP). If the user wants plain captions / subtitles (the spoken words as text) → /embedded-captions; a single short unnarrated element (one logo sting / lower-third) → /motion-graphics. The clip plays untouched — re-timing, recoloring, reframing, reordering, or audio is NLE editing and out of scope. Building from a URL / topic / PR → the creation workflows. Unsure overlays-vs-captions? Read `/hyperframes-read-first` first.

> Graphic-packaging sibling of `embedded-captions`. Captions add the _spoken words_ > as a readable subtitle; this adds _designed graphics_ on top of the playing video. > Plain subtitles → embedded-captions. Build a video from scratch → the creation > workflows (product-launch-video / faceless-explainer / …).

Inspectable intermediate files in the work directory:

• metadata.json — duration / width / height / fps
• audio.mp3 — extracted audio
• transcript.json — a flat word array [{ text, start, end }, …] (Whisper; no segments, no words wrapper)
• storyboard.json — lightweight card outline (the agent's plan)
• public/cards/card-XX.html — one HTML fragment per card
• public/index.html — final assembled composition
• output.mp4 — rendered video

CLI Resolution

# hyperframes — transcription (local Whisper) + rendering the assembled HTML to MP4
npx hyperframes --help

This skill runs entirely on the hyperframes CLI plus system ffmpeg / ffprobe. Transcription is local Whisper via hyperframes transcribe — no third-party service, API key, or rate-limited proxy.

Workflow

1. Check Environment

npx hyperframes doctor          # ffmpeg, headless browser, render deps
# confirm bundled assets:
ls "<SKILL_DIR>/assets/fonts" "<SKILL_DIR>/assets/vendor/gsap.min.js"

Required:

• ffmpeg / ffprobe (system)
• <SKILL_DIR>/assets/fonts/*.woff2, <SKILL_DIR>/assets/vendor/gsap.min.js (bundled inside this skill, staged to work dir in Step 9)

Transcription needs no key — hyperframes transcribe runs Whisper locally (Step 4).

Strongly recommended on macOS for hyperframes render:

export PRODUCER_BROWSER_GPU_MODE=hardware

2. Create a Work Directory

All artifacts live under videos/<project-name>/ — the same convention as the other video workflows (product-launch-video / faceless-explainer / pr-to-video). Keep the cwd at the workspace root; everything below writes under this one subdirectory.

VIDEO_PATH="/absolute/path/input.mp4"
WORK_DIR="videos/$(basename "$VIDEO_PATH" | sed 's/\.[^.]*$//')"
mkdir -p "$WORK_DIR"

3. Extract Audio and Metadata

# metadata — duration / width / height / fps
ffprobe -v error -select_streams v:0 \
  -show_entries stream=width,height,r_frame_rate \
  -show_entries format=duration -of json "$VIDEO_PATH" > "$WORK_DIR/metadata.json"
# audio
ffmpeg -y -i "$VIDEO_PATH" -vn -acodec libmp3lame -q:a 2 "$WORK_DIR/audio.mp3"

Outputs: metadata.json (read width/height/duration; fps = the r_frame_rate fraction evaluated, e.g. 30000/1001 → 29.97) + audio.mp3.

4. Transcribe

npx hyperframes transcribe "$WORK_DIR/audio.mp3" -d "$WORK_DIR" --json --model small.en

Local Whisper — no API key, no proxy, no rate limit. Writes a word-level transcript.json into the work dir (word text + start / end timestamps). Read it for the word / sentence timings that drive card timing in Step 6; group words into sentences yourself at punctuation / pauses if you need segment-level chunks.

Clamp to media duration. Whisper can return the final word's end a hair past the actual clip length — clamp every card endSec and composition.durationSeconds to the metadata.json duration, or the render will show a black tail past the video.

5. Correct Transcript

transcript.json is a flat array of word objects — [{ "text": "...", "start": s, "end": s }, …] (no segments array, no words wrapper; the per-word key is `text`). Read it and fix obvious ASR errors:

• Homophones, product names, technical terms, punctuation
• Edit a word's text in place; preserve its `start` / `end` timestamps
• There is no pre-grouped segments array — group words into sentences yourself (split at terminal punctuation / pauses) when you need segment-level chunks for card timing

6. Draft a Lightweight Storyboard (in chat)

No CLI involved. Read transcript.json + metadata.json and design cards directly. storyboard.json is an agent-internal planning artifact — no CLI command consumes it; it exists so you can think clearly about timing and content before writing each card's HTML. Keep the shape consistent with the example below so the same outline can drive the composition you author in Step 9:

{
  "schemaVersion": 3,
  "composition": {
    "fps": 30,
    "width": 1080,
    "height": 1920,
    "durationSeconds": 121.2,
    "layout": "portrait",
    "themeId": "noir",
    "seed": 42
  },
  "videoTrack": {
    "sourcePath": "input-video.mp4",
    "startSec": 0,
    "endSec": 121.2,
    "bounds": { "x": 0, "y": 0, "width": 1080, "height": 1920 }
  },
  "subtitles": { "enabled": false },
  "cards": [
    {
      "id": "card-01",
      "intent": "Hook with the speaker's anxious midnight question",
      "startSec": 0.5,
      "endSec": 13.0,
      "accentIndex": 0,
      "zone": "fullscreen",
      "contentHints": {
        "kicker": "AN HONEST QUESTION",
        "title": "The soul-searching question at 11 PM",
        "detail": "Client's 60-second voice message: 'If the RMB appreciates, does that mean my USD policy is a terrible loss?'"
      }
    }
  ]
}

Required Card fields:

Five `zone` values:

When you assemble the composition in Step 9, resolve each card's zone into pixel bounds on the card-host wrapper following the table above. Video bounds are set once at composition level (videoTrack.bounds); to make video appear to "move between cards", author GSAP tweens against #video-wrap in the composition's <script> (see Step 9).

No prescribed card roles, no prescribed narrative arc. Cards emerge from what the video actually says — could be all quotes or all data, could open with a number or with a story. Let the transcript drive the rhythm.

How many takeaways? — auto-infer from duration + density. No fixed upper limit. Pick a base pace from the video duration, then adjust by information density. Only floor is fixed: minimum 5 cards so even short videos have rhythm.

Step 1 — base pace by duration (the natural sec/card for medium density):

Step 2 — density multiplier (multiplies the base pace):

Step 3 — compute:

secPerCard = basePace × densityMultiplier
cardCount  = max(5, round(videoDurationSec / secPerCard))

Examples (notice — no upper clamp; long videos naturally produce more cards):

• 30s reel, single punchline (low density) → 7 × 1.5 = 10.5s/card → round(30/10.5)=3 → floor to 5 cards
• 60s reflective monologue (low density) → 10 × 1.5 = 15s/card → 4 → floor to 5 cards
• 121s talking-head with rich data (high density) → 10 × 0.7 = 7s/card → 17 cards
• 5 min interview, mixed density → 16 × 1.0 = 16s/card → 19 cards
• 10 min deep-dive, high density → 16 × 0.7 = 11s/card → 55 cards
• 30 min lecture, medium density → 28 × 1.0 = 28s/card → 64 cards
• 1 hr podcast, low density → 45 × 1.5 = 67.5s/card → 53 cards

When a card holds longer than ~15s, plan for a richer card (data block, multi-step reveal, several sub-points unfolding with staggered animations) — a static one-liner gets boring past 8s. For long pieces where many cards exceed 30s, consider chunking the timeline into sub-compositions (one .html per chapter, mounted with data-composition-src) so the GSAP timeline per file stays manageable — see the timeline_track_too_dense HyperFrames lint warning.

content can be a plain string ("Title: annualized 5.69%\nNotes: ...") or any JSON shape that captures the data. The agent decides the shape per card.

Optional outro. This skill ships no fixed brand outro. If the user wants a closing card, design a neutral one yourself (wordmark + one-line tagline, ~1.5-2s, fade in -> short hold -> fade out), append it to cards[], and extend composition.durationSeconds to its endSec. Otherwise end on the last content card.

7. Decide Render Strategy

Confirm Visual Direction with User (DO THIS FIRST)

Before you start designing cards or deciding bounds, ask the user to pick the output ratio, the layout, the style, and the card-density preset. Frames are auto-selected from the chosen layout × style combination (see "Auto-pick frame" table below). Before sending the question, precompute two things:

1. `recommendedRatio` from the source video's aspect ratio

(metadata.json width / height):

• sourceAspect = width / height
• sourceAspect ≥ 1.5 (≥ ~3:2 wide) → recommend `16:9`
• sourceAspect ≤ 0.7 (≤ ~9:13 tall) → recommend `9:16`
• 0.7 < sourceAspect < 1.5 (near-square) → recommend `4:5`

Mark the recommended option's label with " (recommended · matches source video X:Y)" so the user sees why it's recommended.

1. `autoCount` from Step 6 (`max(5, round(videoSec / (basePace ×

densityMultiplier)))`) so the "auto" option's label can show the concrete number.

Environment compatibility — pick the best available question channel. Not every runtime exposes the same structured-question tool. Apply this order:

1. `AskUserQuestion` (Claude Code, Anthropic Console) — use the

structured 4-question call below.

1. Other native clarification tool (e.g. ask_question,

request_user_input, IDE-specific prompt) — use that tool with the same 4 question texts and option lists. Preserve the recommendation markers and the precomputed values.

1. No native tool (Codex CLI, plain text-only runtimes) — **ask

directly in normal conversation. Use the plain-text template at the end of this section. Keep it to one message, 4 numbered questions** (the global cap is 2–5 questions per round; we stay inside it).

Rules that apply to every channel:

• Ask at most 2–5 questions per round. Our 4 here fits.
• Even if missing info doesn't block rendering, **ask once to confirm

the parameters that materially affect the final output** (ratio, layout, style, cardCount).

• If the user has already pre-approved defaults ("just use defaults",

"no need to ask", "auto-pick everything") or asked you not to ask — skip the question entirely and use: recommendedRatio, layout="stack" (safest cross-ratio default), style chosen from transcript tone in the most neutral group (editorial/data), autoCount. Tell the user what you picked in one sentence and continue.

Channel A — native `AskUserQuestion`:

// Precompute before the call:
//   recommendedRatio = "16:9" | "9:16" | "4:5"
//   autoCount        = integer (from Step 6)

AskUserQuestion({
  questions: [
    {
      question: "Output video aspect ratio (canvas):",
      header: "Aspect ratio",
      multiSelect: false,
      // Reorder so the recommended option appears FIRST (per AskUserQuestion convention).
      // Append " (recommended · matches source video W×H)" to the recommended option's label.
      options: [
        { label: "16:9 (1920×1080) landscape", description: "TV / YouTube / desktop playback. Most natural when the source video is already landscape; widest canvas." },
        { label: "9:16 (1080×1920) portrait", description: "TikTok / Reels / short-form mobile. Most natural for portrait source; native mobile experience." },
        { label: "4:5 (1080×1350) near-portrait", description: "Instagram feed / WeChat Moments. Best when source is near-square or you want to cover both platforms." }
      ]
    },
    {
      question: "Choose the overall layout: how should the video and cards coexist on the canvas?",
      header: "Layout",
      multiSelect: false,
      options: [
        { label: "side-by-side (split)",  description: "Video and card each take half the canvas. Most stable for interview / data side-by-side; clear visual separation." },
        { label: "top-bottom (stack)",    description: "Video on top (~52%), card below. Classic combo of speaker face + summary card; works well in portrait too." },
        { label: "picture-in-picture (pip)", description: "Card fills the canvas, video shrinks to a rounded corner window. Use when content is primary and speaker is secondary." },
        { label: "full-screen overlay (overlay)", description: "Video plays full-bleed, card floats as a glass layer on top. Strong cinematic / emotional feel." }
      ]
    },
    {
      question: "Choose the card visual style (style):",
      header: "Style group",
      multiSelect: false,
      // NOTE: these 3 groups intentionally match the frame auto-pick matrix
      // rows below, so picking a group resolves both `style` group AND the
      // frame matrix column in one step. Memberships are mutually exclusive.
      options: [
        { label: "warm paper (warm-paper)", description: "academic notebook · editorial big-type · whiteboard hand-drawn · xhs social. Best for interview reflections, product launches, lifestyle, emotional stories." },
        { label: "clinical / cold (clinical)",   description: "audit magazine · swiss grid · terminal CLI · minimal modern. Best for financial analysis, investigative reports, technical tutorials, serious presentations." },
        { label: "experimental / avant-garde (experimental)", description: "geom color-clash geometry · spotlight dark-background. Best for short-form highlights, product launches, strong emotion, cinematic feel." }
      ]
    },
    {
      question: "Card count (takeaway pacing): how many cards to cut?",
      header: "Card count",
      multiSelect: false,
      options: [
        { label: "Auto (recommended) · approx N cards", description: "Inferred automatically from video duration and information density (see Step 6 rules). This run estimates approx N cards. Substitute the real N (your autoCount) into the label." },
        { label: "Fewer · approx round(N × 0.6) cards", description: "Sparser cuts, each card holds longer — suits reflective / slow-paced content." },
        { label: "More · approx round(N × 1.5) cards", description: "Tighter cuts, faster rhythm — suits staccato / data-dense / short-form highlight content." }
      ]
    }
  ]
})

About "Other" — AskUserQuestion automatically adds an "Other" option to the card count question. The user can type a number directly (e.g. "8", "20") as the cardCount target. Parse the input as an integer: if parsing succeeds → use that value (minimum 5 as a floor); if parsing fails → fall back to "auto".

Channel B — plain-text fallback (Codex CLI, runtimes without a native question tool). Post this as one normal message, then wait for the reply. Bullet-style 1/2/3/4 keeps the reply parseable:

I need to confirm four visual