有一個任務從int RGB矩陣生成BMP文件,並從BMP圖像讀取該矩陣。java從像素矩陣和反向創建BMP圖像
我用這個類來生成BMP文件,但它似乎是難以逆轉這種方法來獲取從圖像rgbValues
陣列:
/**
* Class for creating bmp images from the pixel matrix (an int matrix).
* @author eafkuor
* @link http://forum.codecall.net/topic/62457-creating-a-bmp-image-in-java/
*/
import java.io.File;
import java.io.FileOutputStream;
public class BMP {
private final static int BMP_CODE = 19778;
byte[] bytes;
public void saveBMP(String filename, int[][] rgbValues) {
try {
FileOutputStream fos = new FileOutputStream(new File(filename));
bytes = new byte[54 + 3 * rgbValues.length * rgbValues[0].length + getPadding(rgbValues[0].length) * rgbValues.length];
saveFileHeader();
saveInfoHeader(rgbValues.length, rgbValues[0].length);
saveRgbQuad();
saveBitmapData(rgbValues);
fos.write(bytes);
fos.close();
} catch (Exception ignored) {}
}
private void saveFileHeader() {
byte[] a = intToByteCouple(BMP_CODE);
bytes[0] = a[1];
bytes[1] = a[0];
a = intToFourBytes(bytes.length);
bytes[5] = a[0];
bytes[4] = a[1];
bytes[3] = a[2];
bytes[2] = a[3];
//data offset
bytes[10] = 54;
}
private void saveInfoHeader(int height, int width) {
bytes[14] = 40;
byte[] a = intToFourBytes(width);
bytes[22] = a[3];
bytes[23] = a[2];
bytes[24] = a[1];
bytes[25] = a[0];
a = intToFourBytes(height);
bytes[18] = a[3];
bytes[19] = a[2];
bytes[20] = a[1];
bytes[21] = a[0];
bytes[26] = 1;
bytes[28] = 24;
}
private void saveRgbQuad() {
}
private void saveBitmapData(int[][] rgbValues) {
int i;
for (i = 0; i < rgbValues.length; i++) {
writeLine(i, rgbValues);
}
}
private void writeLine(int row, int[][] rgbValues) {
final int offset = 54;
final int rowLength = rgbValues[row].length;
final int padding = getPadding(rgbValues[0].length);
int i;
for (i = 0; i < rowLength; i++) {
int rgb = rgbValues[row][i];
int temp = offset + 3 * (i + rowLength * row) + row * padding;
bytes[temp] = (byte) (rgb >> 16);
bytes[temp + 1] = (byte) (rgb >> 8);
bytes[temp + 2] = (byte) rgb;
}
i--;
int temp = offset + 3 * (i + rowLength * row) + row * padding + 3;
for (int j = 0; j < padding; j++)
bytes[temp + j] = 0;
}
private byte[] intToByteCouple(int x) {
byte[] array = new byte[2];
array[1] = (byte) x;
array[0] = (byte) (x >> 8);
return array;
}
private byte[] intToFourBytes(int x) {
byte[] array = new byte[4];
array[3] = (byte) x;
array[2] = (byte) (x >> 8);
array[1] = (byte) (x >> 16);
array[0] = (byte) (x >> 24);
return array;
}
private int getPadding(int rowLength) {
int padding = (3 * rowLength) % 4;
if (padding != 0)
padding = 4 - padding;
return padding;
}
}
是否有做這樣的事情在任何Java的lib?或者,也許有人可以建議如何反轉BMP文件?
javax.imageio.ImageIO應該爲您處理。 – BarrySW19 2014-10-27 20:13:28
@ BarrySW19它不提供BMP處理 – ovnia 2014-10-27 20:33:11
它應該 - 在我的系統上「System.out.println(Arrays.toString(ImageIO.getReaderFormatNames()));」 [JPG,BMP,BMP,BMP,BMP,PNG,JPEG,PNG,JPEG,PNG, ,WBMP,GIF,gif]「。你的禮物是什麼?實現者位於所有標準Oracle JDK應具有的com.sun.imageio.plugins.bmp包中。 – BarrySW19 2014-10-28 09:34:59