🎉 Fun fact about MiniMax H3: doubling your video length doesn't double the render time, it nearly triples it! 🎉

tl;dr: In the time it takes to render one 20-second clip, you could have rendered nine 5-second ones.

On a beefy GPU, at 768x1280, 20 steps:

• 5s → 6.5 s/it → 2 min gen time
• 10s → 18.5 s/it → 6 min gen time
• 15s → 35.5 s/it → 12 min gen time
• 20s → 60 s/it → 20 min gen time
• 30s → 130 s/it → 43 min gen time

H3 chops video into a grid. Each frame becomes (W÷32) × (H÷32) tokens, and 24fps video compresses down to about 7 of those frames per second.

At 768×1280 that's 24 × 40 = 960 tokens per frame, so roughly 6,700 tokens per second of video.

5 seconds ≈ 36,000 tokens. 20 seconds ≈ 138,000

Count tokens in units of "one 5-second clip" (call it n), and:

seconds per step ≈ 3.3n² + 3.2n

The n² is attention: every token comparing itself to every other token. The n is everything else. Plug in n = 1 and you get 6.5 s/it. Plug in n = 3.8 (a 20s clip) and you get 60.

How many seconds of rendering you pay per second of finished video:

Every second you add makes every previous second more expensive. The first second of a 30-second clip costs three times what the first second of a 5-second clip costs.