Sand-Glass (Prompted Compression) - Chinese-English Translation Density: leaderboard

Sand-Glass (Cui, Yu et al., Bilibili, 2026) tests translation for dubbing under duration limits: 1,000 colloquial Mandarin video-transcript segments, in the prompted-compression setting where the prompt gives the source syllable count and the target band for the target/source syllable ratio. Translation into English targets the 0.8-0.9 band; translation density (BLEU-rho) is back-translation BLEU divided by the achieved syllable ratio, averaged over three runs; higher is better.

Metric: BLEU-rho (back-translation BLEU divided by the target/source syllable ratio; Zh-En, target band 0.8-0.9; 1,000 Mandarin video-transcript segments, prompt gives the source syllable count and target ratio band, mean of 3 runs). Source: arxiv.org. Saturation forecast: Around June 2027. 4 models tracked.

Top models

#ModelScoreOverall rank
1Claude Opus 4.10.38#268
2GPT-5 (Low)0.35#163 (GPT-5)

No result here: #1 Claude Fable 5.2, #2 Gemini 4 Carbon, #5 Claude Opus 5.5.

Interactive version: theaggregate.ai/benchmark?slug=sand-glass-prompted-compression-chinese-english-translation-density · How It Works · Data refreshed daily, snapshot 2026-11-12.