Alibaba Cloud CDN can automatically convert images to the WebP format. You can also convert images on Alibaba Cloud edge nodes to specified formats. This topic describes how to convert images to specified formats.

Note Image editing is a paid service. It is currently free of charge until further notice.

Automatically convert images to WebP

WebP supports both lossy compression and lossless compression. Alibaba Cloud CDN can automatically convert images to the WebP format. After you enable automatic conversion to WebP, Alibaba Cloud CDN determines whether to convert images to the WebP format based on the Accept header in requests. If image/webp is included in the Accept header, images in the response are converted to the WebP format and then cached on the edge nodes. For more information, see Enable image editing.
Notice After you enable automatic conversion to WebP, the cache hit ratio decreases. It automatically increases after a short period of time. Do not enable this feature during peak hours.
Examples
The Accept header used in this topic is for reference only. The actual Accept header shall prevail. In the following example, image/webp is included in the Accept header. This specifies that Alibaba Cloud CDN automatically converts images to the WebP format. 
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9

Convert images to specified formats

Parameters

Set the action to format.

The following table describes the formats to which images can be converted.
Supported format Description
JPEG Converts base images to the JPG or JPEG format.
PNG Converts base images to the PNG format.
WEBP Converts base images to the WebP format.
BMP Converts base images to the BMP format.
GIF Converts base images to the GIF format.
Note GIF images are animated. If you convert a GIF image to another format, the image is no longer animated and becomes static.
TIFF Converts base images to the TIFF format.
JPEG 2000 Converts base images to the JPEG 2000 format. The suffix of a JPEG 2000 image name is JP2.
Examples
image_process=format,bmp