Chalkboard — our demo

One example among many. Don't reuse its story, arc, shots, props or timings.

Demo: The Story of Chinese Characters 《漢字的故事》 (49.3 s) · chalkboard.mp4 · chalkboard.srt · source in demo/

A child has left a question in the corner of a freshly wiped classroom board: are 射 (shoot) and 矮 (short) swapped? A teacher's voice in Chinese tells the story; a subtitle plate carries each line in Chinese and English. Every fact and its source is in demo/FACTS.md.

Story & structure

Online, people say the two characters got swapped: 射 is 身 + 寸, "one inch tall", so it should mean short; 矮 is 矢 (an arrow) + 委 (to let go), "let an arrow go", so it should mean shoot. The front panel slides away and the back board writes 射 through time: a bow with an arrow, then a hand pulling the string, then the bow bent into 身 and the hand into 寸. 矮 has an arrow because arrows were once used as rulers, and 短 (short) has one too: an orange arrow is laid along a line and ticks off lengths. One wipe removes the wrong readings; the right ones are written in the same place, and after a held beat the answer goes under the child's question: 沒弄反, not swapped. The panel slides back for the end card.

Native moves spent: drying wet streak (opening), second hand (the child's question), write–wipe–rewrite in place (the verdict), tracked component in orange (the bow → 身, the 矢), sliding panel reveal (away and back), chalk as a measuring tool (the arrow-ruler), a line sewing two boards.

Shots

# Time Shot Camera Native move / note
1 0–2.7 title 漢字的故事 / The Story of Chinese Characters written at the top of the front panel close
2 2.7–5.7 the wet streak dries; 射 and 矮 go into their grids; the child's yellow question and the date pull to the question frame drying wet streak, second hand
3 5.7–10.7 射 close: 身 · 寸 underlined and labelled, "一寸高？ / An inch tall?" close, then widen
4 10.7–17.5 矮: 矢 · 委, "放箭？ / Let an arrow fly?", two white crossed arrows locked medium the claim
5 17.5–18.5 front panel slides right; whip to the back board; a timeline is drawn locked, whip sliding panel
6 18.5–21.8 oracle-bone form: an orange bow with a white arrow close pan tracked component
7 21.8–24.4 bronze form: bow and arrow, then a hand lands on the string as the voice names it pan
8 24.4–28.7 seal and regular script, the bow orange in both; 身←弓 · 寸←手 / body ← bow · inch ← hand pan, push out
9 28.7–33.5 短 with an orange 矢; 以矢為正 / the arrow is the ruler; the arrow-ruler; an orange line leaves along the bottom locked medium chalk as a measuring tool
10 33.5–39.7 the line crosses the seam and circles the 矢 under 矮; one wipe; 弓 + 手 / bow + hand, 矢 + 委 / arrow → length · wei → sound; 1.5 s hold same frame as shot 4 write–wipe–rewrite
11 39.7–43.0 沒弄反 ✓ / Not swapped under the child's question same frame the verdict
12 43.0–45.2 the whole front wall: both boards, tray, clock at 7:58, window light pull back, hold summary
13 45.2–49.3 the front panel slides back; on the clean panel: title and sign-off locked end card

Voice

Edge TTS zh-CN-XiaoxiaoNeural at +15 % (demo/lines.json). Readings fixed in say only: 矢 → 史 (shǐ), 委 → 偉 (wěi), 量 → 良 (liáng). Lines start 0.35–0.5 s after the previous one ends; the only longer hold, 1.5 s, comes before the verdict.

# Chinese (spoken) English (subtitle)
1 網上有個說法：射和矮，這兩個字弄反了。 People online say the characters 射 and 矮 got swapped.
2 射字左邊是身，右邊是寸。身高一寸，那不就是矮嗎？ 射 is 身 (body) plus 寸 (inch). One inch tall: isn't that short?
3 矮字左邊是矢，矢就是箭；右邊是委，有放下的意思。把箭放出去，那不就是射嗎？ On the left of 矮 is 矢, an arrow; on the right is 委, to let go. Letting an arrow go: isn't that shooting?
4 其實，射最早畫的是一張弓，弓上搭著一支箭。 In fact, the oldest 射 is a bow with an arrow on it.
5 後來又加了一隻手，在拉弓弦。 Later a hand was added, pulling the string.
6 弓慢慢寫成了身，手寫成了寸。 The bow slowly became 身, and the hand became 寸.
7 那矮裡為什麼有支箭？古人拿箭當尺子，用來量長短。所以短字裡，也有這支箭。 Why is there an arrow in 矮? People once used arrows as rulers to measure length. That is why 短 (short) has one too.
8 射，是拉弓放箭；矮，就是個子短，委只管讀音。 射 means drawing a bow and shooting; 矮 means short, and 委 only gives the sound.
9 所以，沒弄反。 So they were never swapped.

Subtitles split each line at sentence ends (one cue per sentence, Chinese line over English line), timed by each sentence's share of the spoken characters. An English-voice version uses the same picture: en-US-AvaNeural at +10 % (n1, n5, n6 at +14 %, n7 at +12 %; n6 drops "slowly" in the spoken text), the characters read in pinyin (Shè, Ǎi, Shēn, Shǐ, Wěi, Duǎn; 寸 as "Tsun"), each line starting with its Chinese line (demo/lines_en.json, sh demo/build.sh en).

Score structure

Cold open on room tone and chalk. Two guqin notes mark 射 and 矮 finished. From the panel slide, a quiet pulse in D (marimba and pizzicato bass, two notes a second); the oracle-bone bow "sounds" an open A on the guqin and each later form adds a note. A rising marimba run follows the orange line and hangs on a suspended chord through the wipe; the check mark lands on D with a guqin harmonic; the motif plays in full over the wall with a distant bell. The score ducks about 17 dB under the voice and comes up in the pauses. Mix −16 LUFS, true peak −4.0 dBFS before mastering.

Palette & props

Slate #0f1c15 with slow mottling; white chalk, orange chalk (the bow, 身, the 矢, the arrow-ruler and the line), pale yellow for the child. Front panels with two painted tian-zi grids, a back board with one small grid, wooden frame and stiles, a tray with two white sticks and an orange stub, a wall clock at 7:58, a warm white wall and green dado, a faint window patch on the lower left.

End card

The front panel slides back over the rewritten board; on the clean right panel 漢字的故事 / The Story of Chinese Characters and "LemoLab × Claude Opus 5.5" are written in chalk and held about 3.5 s. The licence credit for the chalk recording (Work With Sounds, CC BY 4.0) is already on that panel in small chalk when it slides back: its strokes are dated before the film starts, so they draw whole and add no chalk sound. The sign-off belongs to this library's demo only; a user's film carries no LemoLab credit and no copy of this card.

Build notes