The circle feature allows you to crop an image into a circle of a specified radius. The center of the circle is the center of the image. This topic introduces the parameters and provides examples of the circle feature.

Supported parameters

Parameter	Description	Value	Required
r	The radius of the circle.	[1,4096]	Yes

Notes

If the output format does not support an alpha channel, such as JPG or JPEG, the area outside the circle will be filled with white.

If the input format supports an alpha channel, such as PNG, WebP, BMP, or other raster image formats, the area outside the circle will be transparent. We recommend that you save as a PNG file.

If the radius exceeds half of the length of the short side of the original image, it will automatically be set to half of that side.

Examples

Set the radius to 200, the output format to JPG, and fill the area outside the circle with white.

http://tos-tools.tos-cn-beijing.volces.com/misc/sample.png?x-tos-process=image/circle,r_200/format,jpg

Set the radius to 180, the output format to PNG, and make the area outside the circle transparent.

https://tos-tools.tos-cn-beijing.volces.com/misc/sample.png?x-tos-process=image/circle,r_180/format,png

Last updated: 2026.02.03 17:51:49

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