Dynamic Route for CDN (DCDN) allows you to edit images stored on DCDN nodes. For example, you can add watermarks to images and convert image formats. This topic describes how to edit images and the benefits of this feature.

Note
  • To use image editing, you must first submit a ticket to activate this feature.
  • Image editing is a paid service. It is currently free of charge until further notice.

Benefits

  • Accelerated delivery

    After a base image is cached on CDN nodes, the CDN nodes directly resize the image based on requests and return resized images to clients. This improves delivery efficiency.

  • Reduced loads on origin servers

    If images are edited and stored on origin servers, the images consume storage and computing resources of the origin servers and increase the expense on maintaining origin servers. The image editing feature allows you to edit and cache images on DCDN nodes. This reduces the loads on origin servers.

  • Improved refresh and prefetch efficiency

    After a base image expires, all images edited based on the base image are expired and become unavailable. To address this issue, images are edited and cached on CDN nodes. This solution reduces the frequency of refresh and prefetch tasks and the amount of bandwidth resources consumed by requests that are redirected to origin servers. Newly edited mages are cached on CDN nodes to ensure the availability of base images and edited images.

  • Image editing on CDN nodes

    This feature can recognize image editing parameters and edit images to adapt to different browsers and clients. It helps you meet the requirements of different users.

Configure image editing

DCDN allows you to edit images that are cached on DCDN nodes by passing the image_process parameter to requests. Then, you can specify one or more actions, such as crop and rotate, to edit an image in various ways. Separate multiple actions with forward slashes (/).

  • Format: image_process=action1,param_value1/action2,param_value2.
  • Example: image_process=resize,l_200/quality,q_90/format,webp.

Actions

You can specify one or more actions to edit an image. The following table describes the actions that you can specify to edit images stored on DCDN nodes.

Feature Action Description
Convert image formats format Converts images to a specified format.
Change image quality quality Adjusts the quality of images.
Crop images crop Crops images based on a specified size.
Resize images resize Resizes images to a specified size.
Rotate images
  • auto-orient: automatically rotates images
  • rotate: rotates images to a specified orientation
Automatically rotates images to a proper orientation if the images carry the orientation property, or rotates images clockwise based on a specified angle.
Change the color of an image
  • bright: specifies the brightness of images
  • contrast: specifies the contrast of images
  • sharpen: specifies the sharpness of images
Changes the brightness, contrast, and sharpness of images.
Manage image watermarks watermark Adds picture or text watermarks to images.
Query image information info Queries image information, including the width, height, format, and quality.