好的，那么您将面临的基本问题。大多数图像格式都对图像数据进行某种压缩，它们还可能将有关图像的重要数据附加到文件的末尾，例如颜色模型信息，这使得在读取它们时渲染它们有些困难。
您需要通过某种方式将图像的“块”写入文件，以便轻松读回但不会显着增加文件大小。
我的测试图像从 301.68 kb 开始，我的“块”文件格式最终为 1.42 mb，直到我测试了一个最终为 5.63 mb 的未压缩文件时我才特别满意......我想我可以活下去暂时。
该示例使用内置的GZip 压缩，您可以通过使用Apache-Commons-Compress 之类的方式获得更好的压缩
在纸面上，这基本上是做什么的......
- 读取像素数据块，将其写入以逗号分隔的
String，其中每个值都是图像中的给定像素值。该示例读取每个块 10% 的文件。
- 然后使用
GZip 压缩对每个块进行压缩
- 然后使用
Base64 编码对生成的压缩字节进行编码。我个人更喜欢使用Apache-Commons-Encode，因为它减少了对内部/私人课程的依赖。
- 然后将生成的编码
String 写入File，并在行尾放置一个新行。
图片是反向加载的……
- 从文件中读取一行（Base64 编码
String）
-
String 被解码（到压缩的byte 数组）
- 然后将
byte 数组解压缩为逗号分隔的String
- 逗号分隔的
String 是split，生成的像素数据被绘制到后备缓冲区
- 生成的后备缓冲区更新到屏幕...
理论都很好，实现...有点混乱，抱歉，可能会更整洁一些，但你明白了。
这个想法的目的不是一次读取整个Image.dat 文件，而是将其留在原处并一次读取一行......这允许延迟。
现在，在这个例子中，我使用了javax.swing.Timer 来注入一点暂停，老实说，使用SwingWorker 会更好......但我相信你明白了。 ..
import com.sun.org.apache.xerces.internal.impl.dv.util.Base64;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class ConvertImage {
public static void main(String[] args) {
try {
exportImage(new File("/path/to/your/image.jpg"), new File("Image.dat"));
} catch (IOException ex) {
ex.printStackTrace();
}
new ConvertImage();
}
public ConvertImage() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException ex) {
} catch (InstantiationException ex) {
} catch (IllegalAccessException ex) {
} catch (UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame("Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLayout(new BorderLayout());
frame.add(new TestPane());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
public class TestPane extends JPanel {
private int imgWidth = 0;
private int imgHeight = 0;
private BufferedReader br = null;
private BufferedImage imgBuffer;
private int offset;
public TestPane() {
try {
br = new BufferedReader(new FileReader(new File("Image.dat")));
String header = br.readLine();
String[] parts = header.split("x");
imgWidth = Integer.parseInt(parts[0]);
imgHeight = Integer.parseInt(parts[1]);
imgBuffer = new BufferedImage(imgWidth, imgHeight, BufferedImage.TYPE_INT_ARGB);
Timer timer = new Timer(1000, new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
Graphics2D g2d = null;
try {
String text = br.readLine();
if (text != null) {
// Decode the String back to a compressed byte array
byte[] decode = Base64.decode(text);
GZIPInputStream zis = null;
try {
// Decompress the byte array
zis = new GZIPInputStream(new ByteArrayInputStream(decode));
// Build the text representation of the pixels
StringBuilder sb = new StringBuilder(128);
byte[] buffer = new byte[1024];
int bytesRead = -1;
while ((bytesRead = zis.read(buffer)) > -1) {
sb.append(new String(buffer, 0, bytesRead, "UTF-8"));
}
// Split the pixels into individual packed ints
String[] elements = sb.toString().split(",");
g2d = imgBuffer.createGraphics();
for (String element : elements) {
Point p = getPointAt(offset, imgWidth, imgHeight);
g2d.setColor(new Color(Integer.parseInt(element), true));
g2d.drawLine(p.x, p.y, p.x, p.y);
offset++;
}
g2d.dispose();
repaint();
} catch (Exception exp) {
exp.printStackTrace();
}
} else {
try {
br.close();
} catch (Exception exp) {
}
((Timer) e.getSource()).stop();
}
} catch (IOException ex) {
ex.printStackTrace();
try {
br.close();
} catch (Exception exp) {
}
((Timer) e.getSource()).stop();
} finally {
try {
g2d.dispose();
} catch (Exception exp) {
}
}
}
});
timer.start();
} catch (IOException ex) {
ex.printStackTrace();
try {
br.close();
} catch (Exception e) {
}
}
}
@Override
public Dimension getPreferredSize() {
return new Dimension(imgWidth, imgHeight);
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
int x = (getWidth() - imgBuffer.getWidth()) / 2;
int y = (getHeight() - imgBuffer.getHeight()) / 2;
g.drawImage(imgBuffer, x, y, this);
}
}
protected static void exportImage(File in, File out) throws IOException {
BufferedImage img = ImageIO.read(in);
int width = img.getWidth();
int height = img.getHeight();
// Calculate the total "length" of the image
int imageLength = width * height;
// Calculate the length of each line we will produce
// This is the number of pixels per chunk
int runLength = Math.round((width * height) * 0.1f);
// The place to write the output
BufferedWriter bw = null;
try {
bw = new BufferedWriter(new FileWriter(out));
bw.write(width + "x" + height);
bw.newLine();
// Start converting the pixels...
int offset = 0;
while (offset < imageLength) {
// Calculate the size of the next buffer run, we don't want to
// over run the end of the image
int bufferSize = runLength;
if (offset + bufferSize > imageLength) {
bufferSize = imageLength - offset;
}
// Create a buffer to store the pixel results in...
StringBuilder sb = new StringBuilder(bufferSize * 2);
for (int index = 0; index < bufferSize; index++) {
Point p = getPointAt(offset + index, width, height);
if (sb.length() > 0) {
sb.append(",");
}
// Store the pixel
sb.append(img.getRGB(p.x, p.y));
}
// Write the contents to a compressed stream...
ByteArrayOutputStream baos = new ByteArrayOutputStream();
GZIPOutputStream zos = new GZIPOutputStream(baos);
zos.write(sb.toString().getBytes());
zos.flush();
zos.close();
// Encode the compressed results to Base64
String encoded = Base64.encode(baos.toByteArray());
// Write the content...
bw.write(encoded);
bw.newLine();
// Jump to the next "chunk"
offset += bufferSize;
}
} catch (IOException exp) {
exp.printStackTrace();
} finally {
try {
bw.close();
} catch (Exception e) {
}
}
}
public static Point getPointAt(int index, int width, int height) {
Point p = new Point();
p.y = index / width;
p.x = index % width;
return p;
}
}