COS uses the imageMogr2 API provided by CI to adjust an image’s contrast, which is the difference in luminance between the brightest and darkest points in an image (i.e., the contrast in grayscale).
|download_url||URL of the input image, formatted as
|/contrast/&dxlt;value>||Adjusts the contrast of an image. The value must be an integer in the range of [−100, 100].
|/ignore-error/1||If this parameter is carried and the image failed to be processed because it is too large, the input image will be returned with no error reported.|
This example reduces the contrast of an image by 50:
This example processes the image in the same way as in the example above except that a signature is added. The signature is joined with other processing parameters using an ampersand (&):
You can obtain the value of
<signature>by referring to Request Signature.