CI uses the watermark API to add text watermarks in real time. An input image cannot be larger than 32 MB, with its width and height not exceeding 30,000 pixels and the total number of pixels not exceeding 250 million. The width and height of the output image cannot exceed 9,999 pixels. For an input animated image, its total number of pixels (Width x Height x Number of frames) cannot exceed 250 million.
An image can be processed:
download_url?watermark/2/text/<encodedText>
/font/<encodedFont>
/fontsize/<fontSize>
/fill/<encodedColor>
/dissolve/<dissolve>
/gravity/<gravity>
/dx/<dx>
/dy/<dy>
/batch/<type>
/degree/<degree>
/shadow/<shadow>
Note:Spaces and line breaks above are for readability only and can be ignored.
PUT /<ObjectKey> HTTP/1.1
Host: <BucketName-APPID>.cos.<Region>.myqcloud.com
Date: GMT Date
Authorization: Auth String
Pic-Operations:
{
"is_pic_info": 1,
"rules": [{
"fileid": "exampleobject",
"rule": "watermark/2/text/<encodedText>
/font/<encodedFont>
/fontsize/<fontSize>
/fill/<encodedColor>
/dissolve/<dissolve>
/gravity/<gravity>
/dx/<dx>
/dy/<dy>
/batch/<type>
/degree/<degree>
/shadow/<shadow>"
}]
}
POST /<ObjectKey>?image_process HTTP/1.1
Host: <BucketName-APPID>.cos.<Region>.myqcloud.com
Date: GMT Date
Content-length: Size
Authorization: Auth String
Pic-Operations:
{
"is_pic_info": 1,
"rules": [{
"fileid": "exampleobject",
"rule": "watermark/2/text/<encodedText>
/font/<encodedFont>
/fontsize/<fontSize>
/fill/<encodedColor>
/dissolve/<dissolve>
/gravity/<gravity>
/dx/<dx>
/dy/<dy>
/batch/<type>
/degree/<degree>
/shadow/<shadow>"
}]
}
Note:Authorization: Auth String (For more information, please see Request Signature.)
In the code above, watermark
is the operation name and the number 2
indicates that the watermark is a text.
Parameter | Description |
---|---|
download_url | URL of the input image, formatted as &dxlt;BucketName-APPID>.cos.&dxlt;Region>.myqcloud.com/&dxlt;picture name> Example: examplebucket-1250000000.cos.ap-shanghai.myqcloud.com/picture.jpeg |
/text/ | Watermark text, which must be URL-safe Base64-encoded |
/font/ | Font of the text, which must be URL-safe Base64-encoded. Default font: Tahoma.ttf (see supported fonts.) |
/fontsize/ | Font size, in pt. Default value: 13 |
/fill/ | Font color. The value must be in hexadecimal format, for example, #FF0000 . For format conversion, please see RGB Color Codes Chart. The value must be URL-safe Base64-encoded. Default value: #3D3D3D (gray) |
/dissolve/ | Text opacity. Value range: 1−100. Default value: 90 (meaning 90% opacity) |
/gravity/ | Position of the text watermark, which is a square in a 3x3 grid. Default value: southeast |
/dx/ | Horizontal offset in pixels. Default value: 0 |
/dy/ | Vertical offset in pixels. Default value: 0 |
/batch/ | Whether to tile the text watermark. If this parameter is set to 1 , the text watermark will be tiled across the input image. |
/degree/ | Angle to rotate text watermarks. This parameter is valid only when /batch/ is set to 1 . Value range: 0−360. Default value: 0 |
/shadow/ | Text shadow effect. Value range: 0−100. Default value: 0 , indicating no shadow. |
The 3x3 grid position diagram is as follows. Once you specify the gravity
parameter to position your watermark, the corresponding red dot becomes the reference point of the square, and offsets will be relative to this point.
Note:
- If
gravity
is set tocenter
,dx
anddy
are invalid.- If
gravity
is set tonorth
orsouth
,dx
is invalid and the watermark will be centered horizontally.- If
gravity
is set towest
oreast
,dy
is invalid and the watermark will be centered vertically.
Note:Processing upon download is used as an example here, which does not store the output image in a bucket. If you need to store the output image, please see Persistent Image Processing and use Processing upon upload or Processing in-cloud data.
http://examples-1251000004.cos.ap-shanghai.myqcloud.com/sample.jpeg?watermark/2/text/6IW-6K6v5LqRwrfkuIfosaHkvJjlm74/fill/IzNEM0QzRA/fontsize/20/dissolve/50/gravity/northeast/dx/20/dy/20/batch/1/degree/45
After text watermarks are added:
This example processes the image in the same way as in the example above except that a signature is carried. The signature is joined with other processing parameters using an ampersand (&):
http://examples-1251000004.cos.ap-shanghai.myqcloud.com/sample.jpeg?q-sign-algorithm=<signature>&watermark/2/text/6IW-6K6v5LqRwrfkuIfosaHkvJjlm74/fill/IzNEM0QzRA/fontsize/20/dissolve/50/gravity/northeast/dx/20/dy/20/batch/1/degree/45
Note:You can obtain the value of
<signature>
by referring to Request Signature.
To prevent unauthorized users from accessing or downloading the input image by using a URL that does not contain any processing parameter, you can add the processing parameters to the request signature, making the processing parameters the key of the parameter with the value left empty. The following is a simple example for your reference (it might have expired or become inaccessible). For more information, please see Request Signature.
http://examples-1251000004.cos.ap-shanghai.myqcloud.com/sample.jpeg?q-sign-algorithm=sha1&q-ak=AKID********************&q-sign-time=1593342360;1593342720&q-key-time=1593342360;1593342720&q-header-list=&q-url-param-list=watermark%252f1%252fimage%252fahr0cdovl2v4yw1wbgvzlteyntewmdawmdqucgljc2gubxlxy2xvdwquy29tl3nodwl5aw4uanbn%252fgravity%252fsoutheast&q-signature=26a429871963375c88081ef60247c5746e834a98&watermark/1/image/aHR0cDovL2V4YW1wbGVzLTEyNTEwMDAwMDQucGljc2gubXlxY2xvdWQuY29tL3NodWl5aW4uanBn/gravity/southeast
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