Aesthetics checklist

这一页还没有中文版，下面是英文原文。

Go through this list before delivering any cut. Report each rule as A3 ✓ or A3 ✗ (where: shot / timestamp). Breaking a rule on purpose is fine, but write down which rule you broke and why in the project notes.

The rules cover product promos, vlogs and talking-heads. Audio rules live in SOUND.md.

Rhythm

A1. Hold key information for at least 1 s. A title, place name, price, number or logo must sit fully still for ≥ 1 s after it lands, before the next cut or move. Give the hold to what the viewer should remember, not to filler. Self-check: Pause on every “remember this” moment. Is there a full second of stillness? Did the hold go to the right element?

A2. Speed comes from acceleration, not linear motion. Fly-ins and pans use easing and uneven staggers. A group of items arriving should get faster and faster (cut_plan(..., "accelerate")), then rest about 0.5 s when the frame is full. Constant-speed motion reads as a cheap slideshow. A physical metaphor helps: dealing cards, stamping a passport, pins dropping on a map. Self-check: Is anything moving at a constant speed in a straight line? Does each burst speed up and then rest?

A3. Make the first version slower. First cuts are nearly always too fast. Give the main action of the opening a complete arc of ≥ 3 s. Play real interactions (ordering, walking in, typing) at human speed. Leave hold and rest frames in the timeline budget. Self-check: Watch it as a first-time viewer. Where did you miss something? Could you follow along?

A4. Beat sync sets timing, not size. ≤ 3 full-frame hits per video, ≥ 16 beats apart. A full-frame hit is anything that moves the whole frame or camera at once: frame-wide scale pump, shake, flash frame, invert frame. Treat each as a big slam. Each one goes on a strong hit from b.hits. Other on-beat motion moves only the subject layer: a card, a title, a sticker. Kick detections are a pool of candidates, not triggers. Count one technique use as one slot, even if it flashes several times inside. Self-check: Step through any 8 beats of the busiest section frame by frame. Is the whole frame pulsing on every beat? How many full-frame hits are there in total, and does each sit on a listed strong hit?

A5. One transition per cut, taken from the neighbours’ budgets. A transition’s length is borrowed from the two shots it joins: half from the end of one, half from the start of the next. It does not stretch the video. Use a single transition per cut, never two stacked. A plain hard cut is the default. Use a styled transition only where the story changes place, day or mood. Self-check: Does every transition steal its frames from its neighbours? Do the neighbour shots still keep their A1 holds after the steal? Is any cut wearing two effects?

Look and readability

A6. Readable text is ≥ 5 % of frame height. Test it at 480 px wide. Caption and story text needs an on-screen cap height of at least 5 % of frame height: 54 px on 1080p, about 96 px on a 1920-tall vertical. Secondary text (dates, prices, URLs) needs at least 3 %. Measure the rendered frame, including any scale or perspective applied, not the font size in code. Text is either readable or deliberately decorative, never in between. Self-check: Scale one frame from each texted shot down to 480 px wide. Can you still read every line?

A7. Each technique stars once. A signature move (speed ramp, glint sweep, map fly-through, freeze-frame with stamp, split-screen, crash zoom) is strongest the first time. Use it once as the star moment. If it appears again, make it smaller and quieter. Never apply a glint or glow to every item in a group, and clip any glow to the shape that carries it. Self-check: Count each named technique. Does any appear more than once at full strength? Does any glow spill outside its card’s corners?

A8. One subject in the opening. The hook opens on one hero image or action with a complete arc. A crowd of moving pieces can’t hold attention. Self-check: How many things does the opening shot ask you to look at?

A9. Steady camera by default. Add no fake handheld shake to bright, clean footage. Use shake only for a deliberate documentary feel, keep it tiny, and check rendered frames for wobble you didn’t mean. Self-check: Is there any camera motion that serves no story purpose?

A10. The finale is the energy peak. The ending brings back the best moments, plays on the loudest section of the music, and carries the riser → impact → sparkle sentence. First versions of endings are almost always too timid, so push them one notch further. Self-check: Is the finale the most energetic point of the video? Does it bring back each place or highlight once?

Sound (summary, details in SOUND.md)

A11. Choose sounds by genre, and give real actions matching sounds. Does the soundtrack sound like this kind of video with your eyes closed? Does every distinctive on-screen action have its own sound, trimmed to its length?

A12. Picture first, sound last. Repeated sounds alternate and step down. Did any shot length change after the cue sheet was built? If so, rebuild it. Do repeated hits sound countable?

Delivery

A13. Deliver with-music and without-music versions from the same timeline. Both keep voice and SFX. Self-check: Are both files rendered, and does the no-music version still hold up?

A14. Verify the beat sync on the rendered file. Run beats.verify on the cut times. Any cut

3 frames off is a must-fix. A same-direction offset across all cuts points to an output audio offset, not to the analysis.

Travel-fun quick sheet

beats.energy_arc(duration, "travel-fun", beats=b) gives this layout:

Hook (0-8 %): max energy, the best 5-8 shots, ends on a strong hit.
Intro: where, who and why, with the title held ≥ 1 s.
3-5 place or day blocks. Each block is a fast montage that accelerates into a breather (one moment that gets to breathe: a reaction, food, a view, a line). Energy rises block to block.
Peak finale: accelerate cuts, riser → impact → sparkle.
Outro: a slow wide shot and a sign-off.