You can specify Image Processing (IMG) parameters in GetObject requests to process image objects in Object Storage Service (OSS). For example, you can add image watermarks to images or convert image formats.
OSS allows you to use one or more parameters to process images. You can also encapsulate multiple IMG parameters in a style and use the style to process images. For more information about image styles, see Image styles.
If you specify multiple IMG parameters, OSS processes the image based on the parameters in the order they are specified. The following table describes IMG parameters.
Adds image watermarks or text watermarks to images.
Crops rectangular images based on the specified size.
Adjusts the quality of images in the JPG format and WebP format.
Converts the formats of images to specified formats.
Obtains image information, including basic information and Exchangeable Image File Format (EXIF) information.
Crops images into circles of the specified size based on the center point of images.
Crops images along the specified horizontal axis or vertical axis and selects one of the images.
Crops images into rounded rectangles based on the specified rounded radius size.
Rotates images clockwise by a specified angle.
Configures gradual display for JPG images.
Queries the average hue of images.
Adjusts the brightness of images.
Adjusts the contrast of images.
For example, if you add the
quality parameters to process the
example.jpg image, the URL of the image is
https://oss-console-img-demo-cn-hangzhou.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=image/resize,w_300/quality,q_90. You can configure Alibaba Cloud CDN back-to-origin rules to filter out or retain the IMG parameters contained in the URLs of images that you want to retrieve. This way, you can retrieve source images or images that are processed by using IMG parameters.
Retrieve a source image
You can enable the parameter filtering feature of Alibaba Cloud CDN to filter out all parameters that follow the question mark (?) in the URL of the image that you want to retrieve. In this example, the
example.jpgsource image is retrieved.
Retrieve a processed image
You can enable the parameter retaining feature of Alibaba Cloud CDN to retain all parameters that follow the question mark (?) in the URL of the image that you want to retrieve. In this example, the processed image is retrieved.
For more information about Alibaba Cloud CDN back-to-origin rules, see Ignore parameters.
You can use object URLs, API operations, and SDKs to process images. For more information, see IMG implementation modes.
The size of a source image cannot exceed 20 MB.
Image width and height
For the rotate operation, the height or width of a source image cannot exceed 4,096 pixels. For other operations, the width or height of a source image cannot exceed 30,000 pixels, and the total number of pixels of the source image cannot exceed 250 million.
The total pixel number of a dynamic image, such as a GIF image, is calculated based on the following formula:
The width or height of a compressed image cannot exceed 16,384 pixels. The total pixel number of a compressed image cannot exceed 16,777,216.
Advanced image compression
The number of pixels of a compressed HEIC image cannot exceed 4,096 × 4,096. The number of pixels of a compressed AVIF image cannot exceed 4,096 × 2,304.
You can create up to 50 image styles for a bucket. If your business requires more than 50 styles for a bucket, submit a ticket.
You may want to go beyond the preceding limits in computationally intensive business applications, such as encoding WebP, AVIF, or HEIF images at a resolution higher than 1080p. To increase the limits, contact technical support.
You are charged the following fees when you use IMG:
API operation calling fees
A GetObject request is generated each time you use IMG to process an image. You are charged based on the number of generated requests. For more information, see Request fees.
You are charged for the outbound traffic over the Internet based on the size of the processed images. For more information, see Traffic fees.
IMG provides two versions of API operations. This topic describes the new version of the API operations. Update support is no longer provided for the old version. For more information about the compatibility with the new and old versions of API operations, see Differences between the old and new versions of IMG.