OSS Image Service (IMG) is an image processing service that features massive capacity, high security, low costs, and high reliability. By uploading and storing original images in OSS, you can process images anytime, anywhere, on any Internet device through a simple RESTful API.IMG offers image processing APIs.

For more information, see Image processing.

Basic features of Image Service

OSS IMG provides the following features:

Usage of Image Service

Image Service uses the standard HTTP GET request for access. All processing parameters are encoded in the QueyString in the URL.

If the ACL for an image is private read and write, only authorized users are allowed can access the image.

  • Anonymous access

    If the access permission of the image object is public read, as shown in the following table, you can access Image Service anonymously.

    Bucket ACL Object ACL
    Public-read or Public-read-write Default
    Any ACL Public-read or Public-read-write

    Access Image Service anonymously using the third-level domain in the following format:

    http://<yourBucketName>.<yourEndpoint>/<yourObjectName>?x-oss-process=image/<yourAction>,<yourParamValue>
    Parameter Description
    bucket Name of the user’s bucket
    endpoint The access domain name for the data center of the user’s bucket
    object The image object uploaded by the user to the OSS
    image The identifier reserved by Image Service
    action Operations by the user on images, such as scaling, cropping, and rotating
    param Parameters corresponding to the operations by the user on images
    • Basic operations

      For example, scale an image to a width of 100 px and adjust the height based on the ratio. 

      http://image-demo.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=image/resize,w_100
    • Customize image styles

      You can use a level-3 domain name in the following format to access a processed image:

      http://<yourBucketName>.<yourEndpoint>/<yourObjectName>?x-oss-process=style/<yourStyleName>
      • style: The identifier reserved by the system for the user’s custom style
      • yourStyleName: specifies the name of a custom image style. It is the name specified in the rule that is created on the OSS console.

      For example:

      http://image-demo.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=style/oss-pic-style-w-100
    • Cascade operations

      With the cascading processing, you can implement multiple operations on an image. The format is as follows: 

      http://<yourBucketName>.<yourEndpoint>/<yourObjectName>?x-oss-process=image/<yourAction1>,<yourParamValue1>/<yourAction2>,<yourParamValue2>/...

      For example:

      http://image-demo.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=image/resize,w_100/rotate,90
    • Image Service also supports HTTPS access.

      For example,

      https://image-demo.oss-cn-hangzhou.aliyuncs.com/example.jpg?x-oss-process=image/resize,w_100
  • Authorized access

    For objects with private permissions, as shown in the following table, you must be authorized to access Image Service.

    Bucket ACL Object ACL
    private default
    Any ACL private

    The Image Service URL code generated with signature is as follows:

    let OSS = require('ali-oss');
let client = new OSS({
  accessKeyId: '<accessKeyId>',
  accessKeySecret: '<accessKeySecret>',
  bucket: '<bucketName>',
  endpoint: '<endpoint, for exmaple, http://oss-cn-hangzhou.aliyuncs.com>'
});
// Expire after 10 minutes. The image processing style is: "image/resize,w_300".
let signUrl = client.signatureUrl('example.jpg', {expires: 600, 'process' : 'image/resize,w_300'});
console.log("signUrl="+signUrl);
    Note
    • Authorized access supports custom styles, HTTPS, and cascading processing.
    • Expiration time (expires) is measured in seconds.
  • SDK access

    You can directly use SDK to access and process image objects with any ACLs.

    Note The image object processing using SDKs supports custom styles, HTTPS, and cascading processing.
    • Basic operations

      Run the following code to perform basic operations on an image:

      let OSS = require('ali-oss');

let client = new OSS({
  accessKeyId: '<accessKeyId>',
  accessKeySecret: '<accessKeySecret>',
  bucket: '<bucketName>',
  endpoint: '<endpoint, for example, http://oss-cn-hangzhou.aliyuncs.com>'
});

// Scale the image.
async function scale () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/resize,m_fixed,w_100,h_100'})
  } catch (e) {
    console.log(e);
  }
}

scale();

// Crop the image.
async function crop () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/crop,w_100,h_100,x_100,y_100,r_1'})
  } catch (e) {
    console.log(e);
  }
}

crop();

// Rotate the image.
async function rotate() {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/rotate,90'})
  } catch (e) {
    console.log(e);
  }
}

rotate();

// Sharpen the image.
async function sharpen () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/sharpen,100'})
  } catch (e) {
    console.log(e);
  }
}

sharpen();

// Add watermarks.
async function watermark () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/watermark,text_SGVsbG8g5Zu-54mH5pyN5YqhIQ'})
  } catch (e) {
    console.log(e);
  }
}

watermark();

// Convert the image format.
async function format () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/format,png'})
  } catch (e) {
    console.log(e);
  }
}

format();

// Obtain image information.
async function info () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/info})
  } catch (e) {
    console.log(e)
  }
}

info();
    • Customize image styles

      You can run the following code to customize an image style:

      let OSS = require('ali-oss');

let client = new OSS({
  accessKeyId: '<accessKeyId>',
  accessKeySecret: '<accessKeySecret>',
  bucket: '<bucketName>',
  endpoint: '<endpoint, for example, http://oss-cn-hangzhou.aliyuncs.com>'
});

// Custom styles
async function style () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'style/example-sytle'});
  } catch (e) {
    console.log(e);
  }
}

style();
      Note You must first log on to the OSS console to add the custom style 'example-style'.
    • Cascade operations

      Run the following code to perform cascade operations on an image:

      let OSS = require('ali-oss');

let client = new OSS({
  accessKeyId: '<accessKeyId>',
  accessKeySecret: '<accessKeySecret>',
  bucket: '<bucketName>',
  endpoint: '<endpoint, for example, http://oss-cn-hangzhou.aliyuncs.com>'
});

// Cascading processing
async function resize () {
  try {
    let result = await client.signatureUrl('example.jpg', {expires: 3600, process: 'image/resize,m_fixed,w_100,h_100/rotate,90'})
  } catch (e) {
    console.log(e);
  }
}

resize();