本ページの本文は英語で提供されています。タイトルと導入は日本語化されています。
これは何か
Imagen is a text-to-image model Google announced in May 2022. Its key move is to use a frozen large language model (T5-XXL) as the text encoder and to generate with cascaded diffusion: a base image at low resolution is produced first, then a series of super-resolution diffusion models enlarge it step by step. The paper showed that scaling the text encoder improved image–text alignment more than scaling the image generator alone. Imagen did not release its weights and was not offered directly to the public.
なぜ覚えておく価値があるか
It showed that the size of the text encoder is a key lever for text–image alignment and pushed the cascaded-diffusion route to the frontier of photorealistic generation, shaping the design of later models.
主な仕様
- Text encoder
- Frozen T5-XXL
- Generation
- Cascaded diffusion (base + super-resolution)
- Output resolution
- 1024×1024
- Open weights
- No