JIU 0.14.3

net.sourceforge.jiu.color.adjustment
Class Contrast

java.lang.Object
  extended by net.sourceforge.jiu.ops.Operation
      extended by net.sourceforge.jiu.ops.ImageToImageOperation
          extended by net.sourceforge.jiu.ops.LookupTableOperation
              extended by net.sourceforge.jiu.color.adjustment.Contrast

public class Contrast
extends LookupTableOperation

Adjusts the contrast of an image. The amount of adjustment is given to the constructor as a percentage value between -100 and 100. -100 will make the resulting image middle-gray, 0 will leave it unchanged, 100 will map it to the eight corners of the color cube.

Usage examples

Both examples increase contrast by 30 percent.

If all you want is to create a new image with adjusted contrast from the image data of an existing image, simply use the static helper method:

PixelImage adjustedImage = Contrast.adjust(inputImage, 30);
This leaves the original image inputImage unchanged and allocates a second image object which is here assigned to the variable adjustedImage.

If you want more control over parameters, create your own Contrast object. You can then reuse image objects, e.g. to write the adjusted image data to the original image object:

 Contrast op = new Contrast();
 op.setInputImage(image);
 op.setOutputImage(image);
 op.setContrast(30);
 op.process();
 // at this point, image will contain the adjusted image data,
 // the original data wil be overwritten 
 

Author:
Marco Schmidt

Constructor Summary
Contrast()
           
 
Method Summary
static PixelImage adjust(PixelImage input, int percentage)
          This static helper method is more simple to use when all you need are the standard options.
 int getContrast()
          Returns the contrast adjustment value associated with this opperation.
 void process()
          This method does the actual work of the operation.
 void setContrast(int newContrast)
          Sets the value for contrast adjustment to be used within this operation.
 
Methods inherited from class net.sourceforge.jiu.ops.LookupTableOperation
getNumTables, getTable, prepareImages, setNumTables, setTable, setTables
 
Methods inherited from class net.sourceforge.jiu.ops.ImageToImageOperation
canInputAndOutputBeEqual, ensureImagesHaveSameResolution, ensureInputImageIsAvailable, ensureOutputImageResolution, getInputImage, getOutputImage, setCanInputAndOutputBeEqual, setInputImage, setOutputImage
 
Methods inherited from class net.sourceforge.jiu.ops.Operation
addProgressListener, addProgressListeners, getAbort, removeProgressListener, setAbort, setProgress, setProgress
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Contrast

public Contrast()
Method Detail

adjust

public static PixelImage adjust(PixelImage input,
                                int percentage)
This static helper method is more simple to use when all you need are the standard options.

Parameters:
input - the image to work on
percentage - contrast modification, from -100 to 100
Returns:
a new image with adjusted contrast

getContrast

public int getContrast()
Returns the contrast adjustment value associated with this opperation. The value lies between -100 and 100 (including both values).

Returns:
contrast adjustment
See Also:
setContrast(int)

process

public void process()
             throws MissingParameterException,
                    WrongParameterException
Description copied from class: Operation
This method does the actual work of the operation. It must be called after all parameters have been given to the operation object.

Overrides:
process in class LookupTableOperation
Throws:
MissingParameterException - if any mandatory parameter was not given to the operation
WrongParameterException - if at least one of the input parameters was not initialized appropriately (values out of the valid interval, etc.)

setContrast

public void setContrast(int newContrast)
Sets the value for contrast adjustment to be used within this operation.

Parameters:
newContrast - new contrast, between -100 and 100 (including both values)
Throws:
IllegalArgumentException - if the new contrast value is not in the above mentioned interval
See Also:
getContrast()

JIU 0.14.3

Copyright © 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 Marco Schmidt