在 Java 中有效地对图像进行颜色循环
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【中文标题】在 Java 中有效地对图像进行颜色循环【英文标题】：Efficiently color cycling an image in Java 【发布时间】：2011-11-24 13:34:19 【问题描述】：我正在编写一个 Mandelbrot 分形查看器，我想以一种智能的方式实现颜色循环。给定一张图片，我想修改它的 IndexColorModel。
据我所知，无法修改 IndexColorModel，也无法为图像赋予新的 IndexColorModel。事实上，我认为没有办法提取它的颜色模型或图像数据。
似乎唯一的解决方案是保留用于创建图像的原始图像数据和调色板，手动创建一个带有旋转颜色的新调色板，创建一个新的 IndexColorModel，然后创建一个全新的图像来自数据和新的颜色模型。
这一切看起来工作量太大了。有没有更简单快捷的方法？
这是我能想到的最佳解决方案。此代码创建一个 1000x1000 像素的图像，并显示颜色以每秒 30 帧左右的速度循环的动画。
（旧）
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;
public class ColorCycler
public static void main(String[] args)
SwingUtilities.invokeLater(new Runnable()
public void run()
createAndShowGUI();
);
private static void createAndShowGUI()
JFrame jFrame = new JFrame("Color Cycler");
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jFrame.add(new MyPanel());
jFrame.pack();
jFrame.setVisible(true);
class MyPanel extends JPanel implements ActionListener
private byte[] reds = new byte[216];
private byte[] greens = new byte[216];
private byte[] blues = new byte[216];
private final byte[] imageData = new byte[1000 * 1000];
private Image image;
public MyPanel()
generateColors();
generateImageData();
(new Timer(35, this)).start();
// The window size is 1000x1000 pixels.
public Dimension getPreferredSize()
return new Dimension(1000, 1000);
// Generate 216 unique colors for the color model.
private void generateColors()
int index = 0;
for (int i = 0; i < 6; i++)
for (int j = 0; j < 6; j++)
for (int k = 0; k < 6; k++, index++)
reds[index] = (byte) (i * 51);
greens[index] = (byte) (j * 51);
blues[index] = (byte) (k * 51);
// Create the image data for the MemoryImageSource.
// This data is created once and never changed.
private void generateImageData()
for (int i = 0; i < 1000 * 1000; i++)
imageData[i] = (byte) (i % 216);
// Draw the image.
protected void paintComponent(Graphics g)
super.paintComponent(g);
g.drawImage(image, 0, 0, 1000, 1000, null);
// This method is called by the timer every 35 ms.
// It creates the modified image to be drawn.
@Override
public void actionPerformed(ActionEvent e) // Called by Timer.
reds = cycleColors(reds);
greens = cycleColors(greens);
blues = cycleColors(blues);
IndexColorModel colorModel = new IndexColorModel(8, 216, reds, greens, blues);
image = createImage(new MemoryImageSource(1000, 1000, colorModel, imageData, 0, 1000));
repaint();
// Cycle the colors to the right by 1.
private byte[] cycleColors(byte[] colors)
byte[] newColors = new byte[216];
newColors[0] = colors[215];
System.arraycopy(colors, 0, newColors, 1, 215);
return newColors;
编辑 2：
现在我预先计算 IndexColorModels。这意味着在每一帧上我只需要使用新的 IndexColorModel 更新 MemoryImageSource。这似乎是最好的解决方案。
（我还刚刚注意到，在我的分形资源管理器中，我可以在生成的每张图像上重复使用一组预先计算的 IndexColorModel。这意味着 140K 的一次性成本让我可以实时对所有内容进行颜色循环。这是太好了。）
代码如下：
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;
public class ColorCycler
public static void main(String[] args)
SwingUtilities.invokeLater(new Runnable()
public void run()
createAndShowGUI();
);
private static void createAndShowGUI()
JFrame jFrame = new JFrame("Color Cycler");
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jFrame.add(new MyPanel());
jFrame.pack();
jFrame.setVisible(true);
class MyPanel extends JPanel implements ActionListener
private final IndexColorModel[] colorModels = new IndexColorModel[216];
private final byte[] imageData = new byte[1000 * 1000];
private final MemoryImageSource imageSource;
private final Image image;
private int currentFrame = 0;
public MyPanel()
generateColorModels();
generateImageData();
imageSource = new MemoryImageSource(1000, 1000, colorModels[0], imageData, 0, 1000);
imageSource.setAnimated(true);
image = createImage(imageSource);
(new Timer(35, this)).start();
// The window size is 1000x1000 pixels.
public Dimension getPreferredSize()
return new Dimension(1000, 1000);
// Generate 216 unique colors models, one for each frame.
private void generateColorModels()
byte[] reds = new byte[216];
byte[] greens = new byte[216];
byte[] blues = new byte[216];
int index = 0;
for (int i = 0; i < 6; i++)
for (int j = 0; j < 6; j++)
for (int k = 0; k < 6; k++, index++)
reds[index] = (byte) (i * 51);
greens[index] = (byte) (j * 51);
blues[index] = (byte) (k * 51);
for (int i = 0; i < 216; i++)
colorModels[i] = new IndexColorModel(8, 216, reds, greens, blues);
reds = cycleColors(reds);
greens = cycleColors(greens);
blues = cycleColors(blues);
// Create the image data for the MemoryImageSource.
// This data is created once and never changed.
private void generateImageData()
for (int i = 0; i < 1000 * 1000; i++)
imageData[i] = (byte) (i % 216);
// Draw the image.
protected void paintComponent(Graphics g)
super.paintComponent(g);
g.drawImage(image, 0, 0, 1000, 1000, null);
// This method is called by the timer every 35 ms.
// It updates the ImageSource of the image to be drawn.
@Override
public void actionPerformed(ActionEvent e) // Called by Timer.
currentFrame++;
if (currentFrame == 216)
currentFrame = 0;
imageSource.newPixels(imageData, colorModels[currentFrame], 0, 1000);
repaint();
// Cycle the colors to the right by 1.
private byte[] cycleColors(byte[] colors)
byte[] newColors = new byte[216];
newColors[0] = colors[215];
System.arraycopy(colors, 0, newColors, 1, 215);
return newColors;
编辑：（旧）
Heisenbug 建议我使用 MemoryImageSource 的 newPixels() 方法。答案已被删除，但事实证明这是一个好主意。现在我只创建了一个 MemoryImageSource 和一个 Image。在每一帧上，我都会创建一个新的 IndexColorModel 并更新 MemoryImageSource。
这是更新后的代码：（旧）
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import javax.swing.*;
public class ColorCycler
public static void main(String[] args)
SwingUtilities.invokeLater(new Runnable()
public void run()
createAndShowGUI();
);
private static void createAndShowGUI()
JFrame jFrame = new JFrame("Color Cycler");
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
jFrame.add(new MyPanel());
jFrame.pack();
jFrame.setVisible(true);
class MyPanel extends JPanel implements ActionListener
private byte[] reds = new byte[216];
private byte[] greens = new byte[216];
private byte[] blues = new byte[216];
private final byte[] imageData = new byte[1000 * 1000];
private final MemoryImageSource imageSource;
private final Image image;
public MyPanel()
generateColors();
generateImageData();
IndexColorModel colorModel = new IndexColorModel(8, 216, reds, greens, blues);
imageSource = new MemoryImageSource(1000, 1000, colorModel, imageData, 0, 1000);
imageSource.setAnimated(true);
image = createImage(imageSource);
(new Timer(35, this)).start();
// The window size is 1000x1000 pixels.
public Dimension getPreferredSize()
return new Dimension(1000, 1000);
// Generate 216 unique colors for the color model.
private void generateColors()
int index = 0;
for (int i = 0; i < 6; i++)
for (int j = 0; j < 6; j++)
for (int k = 0; k < 6; k++, index++)
reds[index] = (byte) (i * 51);
greens[index] = (byte) (j * 51);
blues[index] = (byte) (k * 51);
// Create the image data for the MemoryImageSource.
// This data is created once and never changed.
private void generateImageData()
for (int i = 0; i < 1000 * 1000; i++)
imageData[i] = (byte) (i % 216);
// Draw the image.
protected void paintComponent(Graphics g)
super.paintComponent(g);
g.drawImage(image, 0, 0, 1000, 1000, null);
// This method is called by the timer every 35 ms.
// It updates the ImageSource of the image to be drawn.
@Override
public void actionPerformed(ActionEvent e) // Called by Timer.
reds = cycleColors(reds);
greens = cycleColors(greens);
blues = cycleColors(blues);
IndexColorModel colorModel = new IndexColorModel(8, 216, reds, greens, blues);
imageSource.newPixels(imageData, colorModel, 0, 1000);
repaint();
// Cycle the colors to the right by 1.
private byte[] cycleColors(byte[] colors)
byte[] newColors = new byte[216];
newColors[0] = colors[215];
System.arraycopy(colors, 0, newColors, 1, 215);
return newColors;
【问题讨论】：
如何预先计算一个循环然后为图像设置动画？ @thomas 上面的代码示例以 1000x1000 像素显示 216 帧。计算的帧每个像素使用 4 个字节。那是 864 MB。我已经尝试过了，我现在特别避免它。 不要预先计算所有帧，只做三个 cluts：3 * 216 * 216 = ~140K 为sscce+1。 @trashgod 你的意思是我应该预先计算 216 个 IndexColorModels，然后为每一帧选择一个使用？ 【参考方案1】：除了预先计算循环之外，作为@Thomas cmets，还可以分解出幻数 1000。下面是您可能喜欢的 Changing the ColorModel of a BufferedImage 和 project 的相关示例。
附录：分解出 magic numbers 将允许您在分析时可靠地更改它们，这是查看您是否取得进展所必需的。
附录：虽然我建议每帧使用三个颜色查找表，但您预先计算 IndexColorModel 实例的想法更好。作为数组的替代方案，可以考虑使用Queue<IndexColorModel>，将LinkedList<IndexColorModel> 作为具体实现。这简化了您的模型旋转，如下所示。
@Override
public void actionPerformed(ActionEvent e) // Called by Timer.
imageSource.newPixels(imageData, models.peek(), 0, N);
models.add(models.remove());
repaint();
附录：动态更改颜色模型和显示时间的另一种变体。
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.IndexColorModel;
import java.awt.image.MemoryImageSource;
import java.util.LinkedList;
import java.util.Queue;
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
/** @see http://***.com/questions/7546025 */
public class ColorCycler
public static void main(String[] args)
SwingUtilities.invokeLater(new Runnable()
@Override
public void run()
new ColorCycler().create();
);
private void create()
JFrame jFrame = new JFrame("Color Cycler");
jFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
final ColorPanel cp = new ColorPanel();
JPanel control = new JPanel();
final JSpinner s = new JSpinner(
new SpinnerNumberModel(cp.colorCount, 2, 256, 1));
s.addChangeListener(new ChangeListener()
@Override
public void stateChanged(ChangeEvent e)
cp.setColorCount(((Integer) s.getValue()).intValue());
);
control.add(new JLabel("Shades:"));
control.add(s);
jFrame.add(cp, BorderLayout.CENTER);
jFrame.add(control, BorderLayout.SOUTH);
jFrame.pack();
jFrame.setLocationRelativeTo(null);
jFrame.setVisible(true);
private static class ColorPanel extends JPanel implements ActionListener
private static final int WIDE = 256;
private static final int PERIOD = 40; // ~25 Hz
private final Queue<IndexColorModel> models =
new LinkedList<IndexColorModel>();
private final MemoryImageSource imageSource;
private final byte[] imageData = new byte[WIDE * WIDE];
private final Image image;
private int colorCount = 128;
public ColorPanel()
generateColorModels();
generateImageData();
imageSource = new MemoryImageSource(
WIDE, WIDE, models.peek(), imageData, 0, WIDE);
imageSource.setAnimated(true);
image = createImage(imageSource);
(new Timer(PERIOD, this)).start();
// The preferred size is NxN pixels.
@Override
public Dimension getPreferredSize()
return new Dimension(WIDE, WIDE);
public void setColorCount(int colorCount)
this.colorCount = colorCount;
generateColorModels();
generateImageData();
repaint();
// Generate MODEL_SIZE unique color models.
private void generateColorModels()
byte[] reds = new byte[colorCount];
byte[] greens = new byte[colorCount];
byte[] blues = new byte[colorCount];
for (int i = 0; i < colorCount; i++)
reds[i] = (byte) (i * 256 / colorCount);
greens[i] = (byte) (i * 256 / colorCount);
blues[i] = (byte) (i * 256 / colorCount);
models.clear();
for (int i = 0; i < colorCount; i++)
reds = rotateColors(reds);
greens = rotateColors(greens);
blues = rotateColors(blues);
models.add(new IndexColorModel(
8, colorCount, reds, greens, blues));
// Rotate colors to the right by one.
private byte[] rotateColors(byte[] colors)
byte[] newColors = new byte[colors.length];
newColors[0] = colors[colors.length - 1];
System.arraycopy(colors, 0, newColors, 1, colors.length - 1);
return newColors;
// Create some data for the MemoryImageSource.
private void generateImageData()
for (int i = 0; i < imageData.length; i++)
imageData[i] = (byte) (i % colorCount);
// Draw the image.
@Override
protected void paintComponent(Graphics g)
super.paintComponent(g);
long start = System.nanoTime();
imageSource.newPixels(imageData, models.peek(), 0, WIDE);
models.add(models.remove());
double delta = (System.nanoTime() - start) / 1000000d;
g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
g.drawString(String.format("%1$5.3f", delta), 5, 15);
// Called by the Timer every PERIOD ms.
@Override
public void actionPerformed(ActionEvent e) // Called by Timer.
repaint();
【讨论】：
你说“分解出神奇的数字 1000”是什么意思？ 我上面已经详细说明了；216 是另一位候选人。
对不起所有的神奇数字。我认为变量会使代码复杂化，但我想它们是必要的。
感谢您修复神奇数字。在代码变体接近尾声时，newColors[0] = colors[215]; 应该是 newColors[0] = colors[MODEL_SIZE - 1];。
@nIcEcOw：遗憾的是，我更新了代码，但没有更新 cmets！ :-)【参考方案2】：
我会使用带有 Mandelbrot 像素着色器的 LWJGL（OpenGL 接口到 Java），并在着色器中进行颜色循环。比使用 Java2D 高效得多。
http://nuclear.mutantstargoat.com/articles/sdr_fract/
【讨论】：
非常相关和一个好主意，但我编写这个程序是为了体验 Swing 和图像处理。不过，谢谢。以上是关于在 Java 中有效地对图像进行颜色循环的主要内容，如果未能解决你的问题，请参考以下文章