Explainer

At the end of this page you have an explainer filmA film is the mp4 file that the renderer makes from one page. of 9 s to 3 min. Each beatA beat is one part of the story with one idea, such as the hook, a feature or the end. shows one idea, and a facts list that you checked backs every claim.

You need a source: a link, a paper, a recipe or an outline.

What this film needs

An explainer teaches. It has no product to sell and no capture to show, so the agent invents the visuals. The picture is the explanation: a diagram that builds, a number that counts, or a process that fills from empty to complete. Type is for labels and one sentence for each beat, never for paragraphs.

The length is 9 s to 3 min (prompts/story-explainer.md). Over 60 s, use the director’s brief (prompts/directors-brief-long-form.md) and one chapter file for each agent. A common length is 30 s in 16:9.

Plan the beat count from the length. The scene-budget rule gives 5 to 7 beats of 3 to 6 s for 30 s, and 8 to 12 beats of 4 to 7 s for 60 s. Beat length varies, and the payoff holds longest.

The hook-payoff rule puts the question in the first 3 s and the payoff, the beat where the idea becomes clear, at 77 to 90 percent of the length. Do not spend the best fact in the hook.

Steps

bin/vawe new fsync --from prompts/story-explainer.md --length 30 --aspect 16:9

bin/vawe dev films/fsync/page.html

Narration and captions

Narration is an <audio src="vo.mp3" data-at="0" data-role="vo"> tag that you supply. data-role="vo" ducks the bedA bed is a music track that plays under the whole film, marked by the loop attribute on an <audio> tag.. Put music under it at a lower gain. Read Audio.

Captions are one <p> for each line, timed with the same table as the narration. The caption-karaoke and caption-editorial moves are built versions. Do not write an em dash on screen.

The agent cannot hear the narration it rendered. Write “pronunciation not checked by the model” in the hand-off, and have a person listen once.

Pitfalls from the taste digest

• Show real things working (show-real-thing). The viewer watches the thing work. A value changes and the output updates. A word in a box is not a beat.
• Text breathing (text-breathing). Readable text fills at most 84 percent of a film. Leave one or two beats with no words.
• Read lines (readable-hold). A caption of 4 words or more holds 0.6 s a word. A diagram that finishes building in 300 ms was not seen.
• Every claim is backed (claim-backed). Show each number in the same beat that states it.
• One thread (thread). Keep one palette and one accent, for the thing explained right now.

A formula with a glyph the font lacks renders a box, so check the glyphs. A count that ends on a rounded number lies: count to the sourced value. Captions and diagram must not share the caption band.

Common mistakes

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