• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 1152
  • Last Modified:

Contrast and Sharpness Code using JAI

Plz tell me code of increase and decrease contrast and sharpen of image using JAI
i have write code for contrast it increase contrast accuratly but decrease code is not giving desired result
  • 2
1 Solution
You basically need to use a JAILookuptable, here's a function that helps you adjust the contrast and brightness of a picture:

public static PlanarImage setColor(PlanarImage source,
int red, int green, int blue,
float contrast,
float brightness)
// Time the process for performance
long beginTime = (new java.util.Date()).getTime();

// Setup the parameter block for the source image and
// the three parameters for the mean operation
ParameterBlock mpb = new ParameterBlock();
mpb.addSource(source); // The source image
mpb.add(null); // null ROI means whole image
mpb.add(1); // check every pixel horizontally
mpb.add(1); // check every pixel vertically
// Perform the mean operation on the source image
PlanarImage meanImage = JAI.create("mean", mpb, null);
// Retrieve the mean pixel value
double[] mean = (double[])meanImage.getProperty("mean");
// Average the mean of all bands
double sum = 0.0D;
for (int i=0; i < mean.length; i++)
sum += mean;
int average = (int) sum / mean.length;

// Create the lookup table based on the average mean
byte[][] lut = new byte[3][256];
for (int i = 0; i < 256; i++ )
lut[0] = clamp((average + (int)((i - average) * contrast)) + red + (int)brightness);
lut[1] = clamp((average + (int)((i - average) * contrast)) + green + (int)brightness);
lut[2] = clamp((average + (int)((i - average) * contrast)) + blue + (int)brightness);
LookupTableJAI lookup = new LookupTableJAI(lut);
// Setup the parameter block for the lookup operation
ParameterBlock pb = new ParameterBlock();

// Calculate processing time and report
long endTime = (new java.util.Date()).getTime();
System.out.println("Time to set colors was " + (endTime - beginTime) + " ms");

// Return the resulting image
return JAI.create("lookup", pb, null);
Another function that could help you:

public void processBrightContrast(int ipParam, Image pImage){

Image mImage = pImage;
//Create parameter block
// java.awt.image.renderable.ParameterBlock mPB = new java.awt.image.renderable.ParameterBlock();
//Add image source to parameter block
// mPB.addSource(mImage);

byte lutData[];
lutData = new byte[256];
for(int j = 0; j < 256; j++)
lutData[j] = clampByte(j + ipParam);

javax.media.jai.LookupTableJAI mLookup = new javax.media.jai.LookupTableJAI(lutData);

// mPB.add(mLookup);

java.awt.image.renderable.ParameterBlock pb = new java.awt.image.renderable.ParameterBlock();
pb.add(mImage); // mImage is a normal image here
PlanarImage im = (PlanarImage)JAI.create("awtImage", pb);

try {
// Process the brightness/ darkness
javax.media.jai.RenderedOp mRenOp = javax.media.jai.JAI.create("lookup", im); //mPB, null); <---- this is where the debug crashes

src = this.toImage(mRenOp.getAsBufferedImage());
catch(IllegalArgumentException e)

Also, check out the JAI programmers guide here for more info:

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Featured Post

Cloud Class® Course: Microsoft Azure 2017

Azure has a changed a lot since it was originally introduce by adding new services and features. Do you know everything you need to about Azure? This course will teach you about the Azure App Service, monitoring and application insights, DevOps, and Team Services.

  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now