This topic describes the image URL rules for image processing.
The image processing service uses standard HTTP GET requests, and all processing parameters are encoded in the URL.
Access the original image
You can access images in two ways:
Third-level domain name
Custom domain name
URL for a third-level domain name
http://channel.<endpoint>/object@action.format<endpoint> specifies the endpoint of the image processing service for the region where your image is stored. For more information, see Endpoints. The object specifies the original image file stored in the associated channel.
URL for a custom domain name
Alternatively, you can access the image using a custom domain name that is attached to the image processing service. The format is as follows:
http://userdomain/objectuserdomain specifies the custom domain name that is attached to the image processing service and associated with a channel. This topic assumes that userdomain is mapped to the `channel.endpoint` third-level domain name using a canonical name (CNAME) record. The object specifies the original image file stored in the associated channel.
Access an image using processing parameters
When you process an original image, the result is returned in one of two URL formats, as follows:
Using a third-level domain name:
http://channel.<endpoint>/object@action.formatchannel: The IMG channel for the user.
endpoint: The endpoint of the data center where your channel is located.
object: The image file that you upload to Object Storage Service (OSS).
action: The operation to perform on the image.
format: The format of the processed image.
Using a custom domain name:
http://userdomain/object@action.format
The following is an example of a typical URL:
http://bucket.endpoint/object@100w_100h_90Q.jpg (Third-level domain name)
http://userdomain/object@100w_100h_90Q.jpg (Custom domain name)
In these examples, @100w_100h_90Q is the transform action, and jpg is the transform format. The combined string 100w_100h_90Q.jpg is called a transform string. It specifies the operation to perform on the target image. When you specify a transform string, a new, processed image is generated and returned.
A typical transform string, such as @100w_100h_90Q.jpg, specifies an image that is 100 px in width (w), 100 px in height (h), has an absolute quality (Q) of 90%, and is in JPG format.
Access an image using a style
You can save a processing method as a style for easier use. To apply the method, specify the style name in the URL. The URL format is as follows:
http://userdomain/object@!style
@! is the supported style separator, and style is the name of the style. For example:
http://image-demo.img.aliyuncs.com/example.jpg@!pipe1
In this example, pipe1 is the style name.