Video Delivery Specs

Video Delivery Specs

Deliver motion content correctly across platforms: produce per-platform spec sheets, repurpose one master into every aspect ratio safely, handle captions and accessibility, and run a pre-delivery QC and collect-files pass before handover.

When to use

Use when exporting or delivering finished motion, when targeting multiple platforms from one master, when checking safe areas for UI-overlay platforms, when deciding caption strategy, or when packaging a project for handover/archive.

Decision tree — master strategy and spec path

Two judgments: what to build as the master so it survives every crop, and which delivery path each platform needs. Decide the master before animating — re-cropping after the fact is where deliveries break.

How many ratios does the brief's distribution need?
├─ One ratio only → animate native to that ratio; no spine needed.
└─ Multiple ratios → build a 16:9 master with a centre 1:1 "title-safe
    spine"; expect to RE-LAYOUT (not just crop) for 9:16.

Per target, which path?
├─ Social (Reels/TikTok/Shorts/Story) → 9:16 1080×1920, H.264 8-12 Mbps,
│   burn in captions, keep action out of top/bottom/right UI zones.
├─ Feed → 4:5 (1080×1350) for most screen real estate.
├─ YouTube long-form → 16:9, upload high-bitrate / ProRes, .srt sidecar.
├─ Broadcast → follow the broadcaster's spec PDF EXACTLY: ProRes 422 HQ,
│   region frame rate, R128/A85 loudness, title-safe 90%, textless + slate.
├─ OOH/signage → pixel-exact to the screen, silent, oversize type.
└─ Web hero → MP4+WebM, muted autoplay loop, compress hard, poster frame.

Rule of thumb: if a platform overlays UI (all vertical social), the safe-area map governs layout before the spec governs export. Get the layout wrong and no bitrate fixes it.

Workflow

1. List target platforms from the brief's distribution line (Reels, Feed, Story, TikTok, YouTube, Shorts, broadcast, OOH, web).
2. Pull each platform's spec (table below; full detail in references/platform-specs.md).
3. Plan the master + cutdowns using the repurposing matrix so the 16:9 master survives the crop to 9:16 and 1:1.
4. Decide captions/accessibility — burned-in vs uploaded, styling, safe placement.
5. Run QC against the checklist, then collect files for handover/archive.

Per-platform spec sheet (essentials)

| Platform | Ratio | Pixels | Duration | Container/codec | Notes | |---|---|---|---|---|---| | IG Reels | 9:16 | 1080×1920 | ≤90s (up to 3min) | MP4/MOV, H.264 | UI overlays bottom + right; keep action centre | | IG Feed | 4:5 or 1:1 | 1080×1350 / 1080×1080 | ≤60s | MP4, H.264 | 4:5 gives most feed real estate | | IG Story | 9:16 | 1080×1920 | ≤60s/card | MP4, H.264 | Top + bottom ~250px reserved for UI | | TikTok | 9:16 | 1080×1920 | 15s-10min | MP4/MOV, H.264 | Heavy right-side + bottom UI; caption-safe centre | | YouTube (horiz) | 16:9 | 1920×1080 (4K 3840×2160) | flexible | MP4, H.264/H.265 | High bitrate; full frame usable | | YouTube Shorts | 9:16 | 1080×1920 | ≤60s | MP4, H.264 | Bottom UI for title/controls | | Broadcast (HD) | 16:9 | 1920×1080 | exact to spec | ProRes 422 (HQ) / per broadcaster | Title-safe 90%, action-safe 93%; legal/loudness | | OOH / digital screen | varies (often 9:16 or custom) | per-site | loop, often 10-15s | MP4/ProRes per vendor | No sound; high legibility; supplied pixel-exact | | Web (hero/embed) | 16:9 or custom | responsive | short loop | MP4 (H.264) + WebM; poster frame | Compress hard; muted autoplay; provide fallback |

Bitrate guidance (H.264): 1080p social 8-12 Mbps; 1080p high-quality 16-20 Mbps; 4K 35-45 Mbps. Audio AAC 320 kbps stereo, 48 kHz. For broadcast/archive use ProRes 422 HQ, not H.264. Full codec/bitrate detail in references/platform-specs.md.

Safe areas and UI danger zones

Social platforms overlay UI on top of the video. Keep titles and key action out of these zones:

• 9:16 (Reels/TikTok/Shorts/Story): reserve top ~250px (handle/close) and bottom ~250-400px (caption, CTA, controls). On TikTok also reserve the right ~120px column (icons). Keep essential text within the centre ~1080×1080 region.
• 16:9 broadcast: title-safe = inner 90%, action-safe = inner 93%. Nothing critical outside title-safe.
• OOH: follow the vendor's exact pixel map and bleed; assume viewing distance — oversize type.

A visual map of each zone is in references/safe-areas.md.

Cutdown / repurposing matrix (one master → all ratios)

Design the 16:9 master so the centre survives cropping. Plan it before animating, not after.

| From → To | Method | Watch for | |---|---|---| | 16:9 → 1:1 | Crop sides to centre 1080 | Text near left/right edges gets cut | | 16:9 → 9:16 | Crop hard to centre + re-stack elements vertically | Wide compositions break; reflow text/logos | | 16:9 → 4:5 | Light side-crop | Usually safe if action is centred | | Master → 6s/15s cutdown | Pick the hook + payoff; drop middle | Re-time, don't just trim; keep brand + CTA |

Best practice: build a "title-safe 1:1 spine" down the centre of the 16:9 master so every crop keeps the message. For 9:16, expect to re-layout rather than crop — budget time for it. Full matrix and a reflow recipe in references/repurposing-matrix.md.

Captions and accessibility

• Open (burned-in) captions: baked into the video. Default for social — most users watch muted, and platform auto-captions are unreliable. Always burn captions for Reels/TikTok/Shorts.
• Closed captions (.srt/.vtt sidecar): uploaded separately; user-toggleable. Required for YouTube long-form and broadcast accessibility compliance; good practice everywhere.
• Styling for burned-in: high contrast (white text, subtle shadow or box), legible weight, 1-2 lines max, placed inside the caption-safe zone (above the bottom UI band, not under it). Sync to speech; ~1-2s per line minimum.
• Beyond captions: avoid conveying meaning by colour alone; keep flashing under 3 flashes/sec (photosensitivity); provide a descriptive title/transcript for screen readers where the platform allows.

Pre-delivery QC checklist (top items)

• Correct dimensions, ratio, and duration for each target.
• First and last frames clean (no black flash, no held render frame).
• Audio present, levels sane, no clipping; broadcast: correct loudness target.
• All text spell-checked; legal/super present and held long enough.
• Logo lockup correct; brand colours match; no placeholder assets.
• Safe areas respected; nothing critical under platform UI.
• Captions accurate and inside the caption-safe zone.
• Export matches codec/bitrate spec; file plays on a fresh machine.
• File names follow convention; versions not mixed up.

Full QC + collect-files checklist in references/qc-checklist.md.

Worked examples

GOOD — one master planned for every crop: > Brief needs 16:9 (web), 1:1 (feed), and 9:16 (Reels + TikTok). You animate a 16:9 master keeping all titles and the logo inside a centre 1:1 spine, then crop to 1:1 cleanly and re-layout (not crop) to 9:16 — restacking the headline above the product, captions burned in above the bottom UI band, action clear of TikTok's right column. Each export matches its platform's bitrate; captions sit inside the caption-safe zone.

ANTI-PATTERN — "we'll just crop it later": > A wide 16:9 hero with the logo bottom-left and a tagline spanning the full width gets center-cropped to 9:16 for Reels. The logo is gone, half the tagline is cut, and the burned-in captions land under the platform's CTA bar where no one can read them.

Why it fails: the master wasn't designed for the crop, and the safe-area map was ignored. The fix is the master strategy above — centre spine, re-layout for vertical, captions above the UI band — decided before animation, not after delivery is due.

Common mistakes

| Symptom | Why it happens | Fix | |---|---|---| | Text/logo cut off after crop | Composed wide, no centre spine | Build a centre 1:1 title-safe spine; re-layout for 9:16 | | Captions hidden under platform UI | Placed at frame bottom, not caption-safe zone | Keep captions above the bottom UI band, inside caption-safe | | Broadcast delivery rejected | Used H.264 / wrong loudness / no textless | Follow the broadcaster spec PDF: ProRes, R128/A85, slate, textless | | Video looks soft after upload | Exported at low bitrate; platform re-compresses | Upload high-bitrate / ProRes; let the platform downscale | | Black flash at start/end | Held render frame or stray black frame | QC first/last frames; trim to intended frames | | Colour shifts outside the editor | Gamma/colour-management mismatch | Spot-check the export in a neutral player before handover | | Wrong file delivered | Versions mixed in the folder | Enforce the naming convention; flag CAPTIONED/TEXTLESS/BROADCAST | | Autoplay web hero won't play | Has audio / too large / no fallback | Muted MP4+WebM, compress hard, poster frame |

Deliverable spec — what a good handover contains

The output is a packaged, dated delivery folder plus the QC pass behind it (full structure in references/qc-checklist.md). A good handover:

• Has every deliverable at the correct ratio, pixels, duration, codec, and bitrate for its target.
• Separates final exports, captioned versions (+ .srt/.vtt), textless masters, and stills.
• Includes a README listing deliverables, specs, and every font/music/stock licence with its usage scope.
• Uses the file-naming convention consistently, with the final version clearly flagged.
• Has passed the full pre-delivery QC checklist before it leaves.

Before you finish — checklist

• [ ] Each target's dimensions, ratio, duration, codec, and bitrate verified.
• [ ] First/last frames clean; no dropped frames or artifacts.
• [ ] Audio correct (or correctly absent); broadcast loudness met.
• [ ] Text spell-checked; legal/super held long enough; logo lockup correct.
• [ ] Safe areas respected; nothing critical under platform UI.
• [ ] Captions accurate, synced, inside the caption-safe zone.
• [ ] Plays on a fresh machine; colour correct outside the editor.
• [ ] File names follow the convention; final version flagged; old versions removed.
• [ ] Handover folder structured; README + licence/rights notes included.

Quick reference

| Need | Answer | |---|---| | Reels/TikTok/Shorts ratio | 9:16, 1080×1920 | | Feed best ratio | 4:5 (1080×1350) | | Social bitrate (1080p) | 8-12 Mbps H.264 | | Broadcast codec | ProRes 422 HQ, not H.264 | | Captions for social | Burn them in (open) | | TikTok danger zones | Bottom + right column | | Broadcast title-safe | Inner 90% | | One master strategy | Centre 1:1 spine in the 16:9 |

Reference files

• references/platform-specs.md — full per-platform spec sheet: exact pixels, durations, codecs, bitrates, audio, and file-size limits.
• references/safe-areas.md — ASCII safe-area maps per ratio with pixel measurements for UI danger zones.
• references/repurposing-matrix.md — full cutdown matrix and a step-by-step 16:9→9:16 reflow recipe.
• references/qc-checklist.md — complete pre-delivery QC checklist plus the Collect-Files / handover packaging list and naming convention.

Source & license

This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code.

• Author: iart-ai
• Source: iart-ai/freelance-motion-skills
• License: MIT
• Homepage: https://www.iart.ai

Install and usage instructions live in the source repository linked above.