ImageSharpen

Description

Sharpens a ColdFusion image by using the unsharp mask filter.

Returns

Nothing.

Category

Image functions

Function syntax

ImageSharpen(name [, gain])

See also

ImageBlur, ImageSetAntialiasing, IsImageFile

History

ColdFusion 8: Added this function.

Parameters

Parameter

Description

name

Required. The ColdFusion image on which this operation is performed.

gain

Optional. -1 <= gain <= 2.

Gain values can be integers or real numbers. The default value is 1.0.

The value determines whether the image is blurred or sharpened:

  • If > 0, the image is sharpened.

  • If = 0, no effect

  • If < 0, the image is blurred.

Usage

Use this function to sharpen outlines in photographs. Use the ImageSetAntialiasing function to improve the quality of the rendered image.

Example

<!--- Create a ColdFusion image from an existing JPEG file. ---> 
<cfimage source="../cfdocs/images/artgallery/paul01.jpg" name="myImage"> 
<!--- Turn on antialiasing to improve image quality. ---> 
<cfset ImageSetAntialiasing(myImage,"on")> 
<!--- Sharpen myImage by 2. ---> 
<cfset ImageSharpen(myImage,2)> 
<!--- Write the sharpened image to a file. ---> 
<cfimage source="#myImage#" action="write" destination="test_myImage.jpg" overwrite="yes"> 
<!--- Display the original and the sharpened images. ---> 
<img src="../cfdocs/images/artgallery/paul01.jpg"/> 
<img src="test_myImage.jpg"/>