In various business contexts, you may need to resize, crop, rotate, or compress images from content sharing websites. However, initiating an origin request for each image processing task can substantially increase the number of origin requests and the cache size on POPs. Alibaba Cloud CDN provides the image editing feature, which allows you to edit images and cache the edited images on POPs. This accelerates content delivery, reduces loads on origin servers, and lowers origin traffic.
The image editing feature of Alibaba Cloud CDN, the image editing feature of DCDN, and the Image Processing (IMG) feature of Object Storage Service (OSS) are three different features.
Image editing is free of charge until further notice.
When you use the image editing feature, conversion between different image formats, such as JPEG to WebP, JPEG to PNG, and PNG to WebP, may result in larger image sizes. This is because different image formats use different compression algorithms. If you want to reduce image sizes, we recommend that you configure the
qualityparameter to reduce the image quality.
Scenarios
After you enable image editing, images are edited and cached on POPs. This reduces loads on origin servers.
The following table describes some common scenarios.
Scenario | Description |
E-commerce platforms |
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Social media |
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Online education |
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Design resource websites |
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Benefits
Image editing provides the following benefits:
Accelerated delivery
After source images are cached on POPs, client requests for images of different sizes can be directly handled on the POPs and edited images are returned from the POPs to the clients. This reduces unnecessary trips to the origin server and ensures faster response times.
Reduced loads on origin servers
Image editing on the origin server consumes a large number of storage and computing resources, which increases the maintenance costs of the origin server. Alibaba Cloud CDN supports image processing and caching on POPs, which alleviates strain on the origin server.
Improved purge and prefetch efficiency
If a source image expires, all images that are edited based on the source image also become unavailable. To address this issue, images are edited and cached on POPs. This solution reduces the necessity of frequent purge and prefetch tasks and the amount of bandwidth resources consumed by origin requests. Also, edited images cached on POPs ensure higher availability, mitigating the impact of source image expiration on content delivery.
Custom image editing on POPs
You can specify image editing parameters to edit images to adapt to different browsers and clients.
Limits
Before you use image editing, take note of the following items:
Source images
You can use this feature to edit only images in the following formats: JPEG, JPG, PNG, WebP, BMP, GIF, TIFF, and JPEG 2000.
The size of a source image cannot exceed 10 MB.
The total number of pixels of a source image cannot exceed 16,777,216.
NoteFor a GIF image, the total number of pixels is the sum of all frames. You can use tools such as ImageMagick to query the frame information about a GIF image.
Edited images
The total number of pixels of an edited image cannot exceed 16,777,216.
If you want to convert an image into the WebP format, the total number of pixels of the image cannot exceed 16,777,216, and neither the width nor the height can exceed 16,384 pixels. If a source image is a dynamic image, a static image is generated when you convert the source image to the WebP format.
Enable and use image editing
For information, see Enable and use image editing.