Class Contrast
java.lang.Object
net.sourceforge.jiu.ops.Operation
net.sourceforge.jiu.ops.ImageToImageOperation
net.sourceforge.jiu.ops.LookupTableOperation
net.sourceforge.jiu.color.adjustment.Contrast
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
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Field Summary
Fields -
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionstatic PixelImage
adjust
(PixelImage input, int percentage) This static helper method is more simple to use when all you need are the standard options.private int[]
createLookupTable
(int numSamples, int contrast) int
Returns the contrast adjustment value associated with this opperation.void
process()
This method does the actual work of the operation.private void
process
(Paletted8Image in, Paletted8Image out) 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
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Field Details
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contrast
private int contrast
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Constructor Details
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Contrast
public Contrast()
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Method Details
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adjust
This static helper method is more simple to use when all you need are the standard options.- Parameters:
input
- the image to work onpercentage
- contrast modification, from -100 to 100- Returns:
- a new image with adjusted contrast
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createLookupTable
private int[] createLookupTable(int numSamples, int 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:
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process
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process
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 classLookupTableOperation
- Throws:
MissingParameterException
- if any mandatory parameter was not given to the operationWrongParameterException
- if at least one of the input parameters was not initialized appropriately (values out of the valid interval, etc.)
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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:
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