Это действительно базовая гистограмма, и, честно говоря, я не знаю, насколько она правильная ... но я надеюсь, что она вам пригодится
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Histogram extends JPanel {
private int SIZE = 256;
// Red, Green, Blue
private int NUMBER_OF_COLOURS = 3;
public final int RED = 0;
public final int GREEN = 1;
public final int BLUE = 2;
private int[][] colourBins;
private volatile boolean loaded = false;
private int maxY;
/**
*
* @param Path
* of image to create Histogram of.
*/
public Histogram() {
colourBins = new int[NUMBER_OF_COLOURS][];
for (int i = 0; i < NUMBER_OF_COLOURS; i++) {
colourBins[i] = new int[SIZE];
}
loaded = false;
}
public void load(String path) throws IOException {
BufferedImage bi = ImageIO.read(new File(path));
// Reset all the bins
for (int i = 0; i < NUMBER_OF_COLOURS; i++) {
for (int j = 0; j < SIZE; j++) {
colourBins[i][j] = 0;
}
}
for (int x = 0; x < bi.getWidth(); x++) {
for (int y = 0; y < bi.getHeight(); y++) {
Color c = new Color(bi.getRGB(x, y));
colourBins[RED][c.getRed()]++;
colourBins[GREEN][c.getGreen()]++;
colourBins[BLUE][c.getBlue()]++;
}
}
maxY = 0;
for (int i = 0; i < NUMBER_OF_COLOURS; i++) {
for (int j = 0; j < SIZE; j++) {
if (maxY < colourBins[i][j]) {
maxY = colourBins[i][j];
}
}
}
loaded = true;
}
@Override
public void paint(Graphics g) {
if (loaded) {
Graphics2D g2 = (Graphics2D)g;
g2.setColor(Color.white);
g2.fillRect(0, 0, getWidth(), getHeight());
g2.setStroke(new BasicStroke(2));
int xInterval = (int) ((double)getWidth() / ((double)SIZE+1));
g2.setColor(Color.black);
for (int i = 0; i < NUMBER_OF_COLOURS; i++) {
// Set the graph
if (i == RED) {
g2.setColor(Color.red);
} else if (i == GREEN) {
g2.setColor(Color.GREEN);
} else if (i == BLUE) {
g2.setColor(Color.blue);
}
// draw the graph for the spesific colour.
for (int j = 0; j < SIZE - 1 ; j++) {
int value = (int) (((double)colourBins[i][j] / (double)maxY) * getHeight());
int value2 = (int) (((double)colourBins[i][j+1] / (double)maxY) * getHeight());
g2.drawLine(j * xInterval, getHeight() - value, (j+1)*xInterval, getHeight() - value2);
}
}
} else {
super.paint(g);
}
}
public static void main(String[] args) {
JFrame frame = new JFrame("Debug Frame");
frame.setSize(200, 200);
frame.setLayout(new BorderLayout());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Histogram his = new Histogram();
try {
his.load("c:/scratch/andriod.png");
} catch (IOException e) {
e.printStackTrace();
}
frame.add(his,BorderLayout.CENTER);
frame.setVisible(true);
}
}