Aspect ratio
Aspect ratio is the proportional relationship between an image’s width and height, usually set by a model parameter rather than described in words.
Aspect ratio changes composition, not just cropping: a 16:9 frame invites a horizon and negative space, a 1:1 frame centres the subject. Most image models accept it as a flag such as `--ar 16:9` appended to the prompt.
Related terms
- Descriptor stack
- A descriptor stack is the comma-separated list of visual attributes that makes up an image prompt, ordered from subject through environment, composition, lighting, and style.
- Image prompt
- An image prompt is a description given to an image generation model specifying the subject, setting, composition, lighting, and style of the picture to produce.
More on image prompting
See the full glossary, read the guides, or put it into practice in the prompt builder.