Files
video/skills/creative/cinematic.md
T
calesthio fdd6457fed docs(prompting): adopt 5-aspect video specification across skills
Incorporate the structured taxonomy from Lin et al. "Building a Precise
Video Language with Human-AI Oversight" (CMU/Harvard, arXiv 2604.21718v2).
The paper proves prompts structured around five aspects (Subject /
Subject Motion / Scene / Spatial Framing / Camera) unlock controllable
cinematography in fine-tuned video generation models. Off-the-shelf VLMs
already nail subject and scene; the gains live in motion, spatial, and
camera, which prompts routinely omit.

Universal layer (skills/creative/video-gen-prompting.md, +125 lines):
- 5-aspect prompt skeleton replaces flat formula
- Camera movements regrouped (translation / rotation / lens-only) with
  dolly!=zoom, pan!=truck, bird's-eye!=aerial disambiguations
- New primitive tables: camera height, camera angle, POV, lens
  distortion (fisheye vs barrel), focus / DoF (rack / pull / tracking),
  playback speed (6 modes), subject transitions
- Order-matters and self-contained-prompt rules
- Identity anchoring rule for multi-shot
- Strict static-shot rule, anti-subjective callout, overlays-not-depth
- Per-model word-count guidance

Per-model guides (sora, veo, hunyuan, ltx, seedance):
- Add the primitives each model honors literally
- Word-count sweet spots per model
- Strengthen seedance verbatim-identity and subject-transition guidance

Pipeline directors (cinematic / explainer / animation scene-director,
cinematic / explainer asset-director):
- 5-aspect scene-plan checklist (per-pipeline adapted)
- Overlays-not-depth callout
- Pre / critique / post self-review loop for generation prompts

Reviewer (skills/meta/reviewer.md):
- CHAI critique-quality rules: accurate / complete / constructive
- Critical findings now require a proposed_fix

Storytelling, cinematic, broll, video-reference-analyst:
- Anti-subjective rule (replace mood adjectives with visual causes)
- Camera-intent-per-beat for script writers
- POV column in stock-footage query templates
- 5-aspect structured output mandatory for reference-video analysis

skills/INDEX.md: video-gen-prompting marked as canonical 5-aspect spec.
2026-04-28 08:11:31 -07:00

7.1 KiB

Cinematic Video Pipeline

Sources: No Film School editorial guides, StudioBinder filmmaking resources, Film Riot production tutorials, CinematographyDB shot databases, Walter Murch "In the Blink of an Eye"

For the universal cinematography vocabulary (camera, lens, motion, focus primitives, plus the 5-aspect Subject / Subject Motion / Scene / Spatial Framing / Camera spec), see skills/creative/video-gen-prompting.md. This file layers cinematic-specific conventions on top of those primitives — it does not redefine them.

Quick Reference Card

ASPECT RATIO:     2.39:1 (widescreen cinematic) or 16:9 with letterbox
LETTERBOX:        Black bars at top/bottom — 1920x800 active area in 1920x1080 frame
FRAME RATE:       24fps (cinematic standard)
SHOT DURATION:    4-8 seconds average (longer than explainer, shorter than documentary)
COLOR GRADE:      cinematic_warm or cinematic_cool profile
AUDIO:            Layered: dialogue + ambient + Foley + score
MUSIC:            60-90 BPM, orchestral or ambient, dynamic (not loop-based)
TARGET LUFS:      -14 LUFS integrated, -24 LUFS for quiet moments

Replace Mood Adjectives with Visual Causes

"Cinematic" and "epic" don't constrain pixels. The cinematic look comes from concrete choices: aspect ratio, lens, lighting key, color grade, shot duration, and audio layer count. State those — the rest is decoration.

The CMU/Harvard CHAI study showed subjective phrasing varies wildly across annotators and model interpretations, which means a beat tagged "moody" routes to a different visual every render. Replace the adjective with the lighting + grade + shot-duration combination that produces moodiness. See skills/creative/storytelling.md "Anti-Subjective Rule" for the script-side equivalent.

Mood adjective Cinematic translation
"epic" 2.39:1 letterbox, 24fps, 8s+ shot duration, orchestral score with crescendo
"moody" moody_dark grade at 0.6, key light at 1/8 fill, 6s+ contemplative shots, ambient bed at -28dB
"intimate" 1.85:1, 40-50mm equivalent, shallow DoF, 2 audio layers (dialogue + room tone), no music under dialogue
"cinematic" (this word is banned — pick one of the above or describe the actual choices)

Aspect Ratios

Ratio Resolution (in 1080p frame) Feel When to Use
2.39:1 (anamorphic) 1920x803 (138px bars each) Epic, cinematic, grand Cinematic explainers, brand films
2.35:1 (scope) 1920x817 (131px bars each) Classic film Similar to 2.39:1, slightly taller
1.85:1 (flat) 1920x1038 (21px bars each) Moderate cinematic Subtle letterbox, less dramatic
16:9 (no letterbox) 1920x1080 Standard Default, no cinematic treatment

Implementing Letterbox in FFmpeg

# Add 2.39:1 letterbox (138px black bars top and bottom)
ffmpeg -i input.mp4 -vf "pad=1920:1080:0:138:black,crop=1920:1080:0:0" output.mp4

# Or render at native ratio and pad:
ffmpeg -i input.mp4 -vf "scale=1920:803,pad=1920:1080:0:138:black" output.mp4

Rule: Only use letterbox when the content genuinely benefits from cinematic framing. Don't letterbox a screen recording or talking head — it just wastes pixels.

Shot Duration and Pacing

Average Shot Length by Style

Style Average Shot Cuts/Minute
Action/intense 2-4s 15-30
Standard cinematic 4-8s 8-15
Documentary 6-12s 5-10
Contemplative 10-20s 3-6
Montage sequence 1-3s 20-40

Pacing Rhythm

Cinematic pacing follows a breathing rhythm — vary shot length deliberately:

Long (8s) → Medium (5s) → Short (3s) → Short (2s) → LONG (10s) → Medium (6s)

Never use the same shot length 3 times in a row — it creates monotony.

The Murch Rule

Walter Murch's editing priorities (in order of importance):

  1. Emotion — does the cut serve the emotional arc?
  2. Story — does the cut advance the narrative?
  3. Rhythm — does the cut feel right in the pacing?
  4. Eye trace — where is the viewer looking?
  5. 2D plane — screen geography (180-degree rule)
  6. 3D space — spatial continuity

For OpenMontage explainers using cinematic style: prioritize rhythm and story over spatial concerns (since we're often cutting between generated images, not continuous footage).

Audio Layering

Cinematic audio has 4 layers (not just voiceover + music):

Layer Level Content
Dialogue/narration -12 dB peak Primary voice
Music/score -24 to -18 dB Orchestral, ambient, dynamic
Ambient/room tone -30 to -24 dB Environmental sound bed
Foley/SFX -18 to -12 dB Specific action sounds

Music for Cinematic

Characteristic Value
BPM 60-90 (slower than standard explainer)
Genre Orchestral, ambient, piano, cinematic electronic
Dynamics Dynamic (crescendos, swells, quiet moments) — NOT loop-based
Key changes At narrative turning points
Silence Deliberately remove music for 3-5s at key reveals

Ambient Sound

Add a subtle ambient layer to fill silence and create depth:

  • Room tone / air conditioning hum (very low, -35 dB)
  • Environmental sounds matching the topic (city, nature, lab)
  • Generates "presence" even during narration pauses

Color Grading for Cinematic

Look Profile Intensity Characteristics
Warm cinematic cinematic_warm 0.85 Orange highlights, lifted shadows
Teal & orange cinematic_cool 0.7 Classic Hollywood blockbuster look
Moody dark moody_dark 0.6 Crushed blacks, low saturation
Vintage film vintage_film 0.7 Faded, warm tint, reduced contrast

Cinematic grading rules:

  • Shadows should be slightly lifted (never pure black)
  • Highlights should be slightly rolled off (never pure white)
  • Skin tones must stay on the vectorscope skin tone line
  • Consistency across all clips — one LUT/profile for the entire video
  • If a beat is described as "moody," rewrite as the lighting + grade + shot-duration combination that produces moodiness. Don't pass mood adjectives to the asset/edit stages.

Applying to OpenMontage

When building cinematic-style content:

  1. Set aspect ratio — use 2.39:1 letterbox for true cinematic, or 16:9 with cinematic_warm grade for subtle
  2. Render at 24fps if the content is purely generated/animated (set in video_compose)
  3. Shot duration 4-8 seconds average — vary deliberately, never same length 3x
  4. Layer audio — narration + music + ambient minimum; add Foley SFX at key moments
  5. Music at 60-90 BPM, dynamic (not looping) — use music_gen with "cinematic orchestral" prompt
  6. Remove music for 3-5 seconds at key reveals — silence is powerful
  7. Color grade with cinematic_warm or cinematic_cool at 0.7-0.85 intensity
  8. Image prompts should include "cinematic lighting, shallow depth of field, film grain" for matching aesthetic
  9. Slower narration — 140-150 WPM (slower than standard 155 WPM explainer pace)