java图像处理实例

一读取bmp图片数据

// 获取待检测图像，数据保存在数组 nData[]，nB[] ，nG[] ，nR[]中

public void getBMPImage(String source) throws Exception {

clearNData(); //清除数据保存区

FileInputStream fs = null;

try {

fs = new FileInputStream(source);

int bfLen = 14;

byte bf[] = new byte[bfLen];

fs.read(bf, 0, bfLen); // 读取14字节BMP文件头

int biLen = 40;

byte bi[] = new byte[biLen];

fs.read(bi, 0, biLen); // 读取40字节BMP信息头

// 源图宽度

nWidth = (((int) bi[7] & 0xff) << 24)

| (((int) bi[6] & 0xff) << 16)

| (((int) bi[5] & 0xff) << 8) | (int) bi[4] & 0xff;

// 源图高度

nHeight = (((int) bi[11] & 0xff) << 24)

| (((int) bi[10] & 0xff) << 16)

| (((int) bi[9] & 0xff) << 8) | (int) bi[8] & 0xff;

// 位数

nBitCount = (((int) bi[15] & 0xff) << 8) | (int) bi[14] & 0xff;

// 源图大小

int nSizeImage = (((int) bi[23] & 0xff) << 24)

| (((int) bi[22] & 0xff) << 16)

| (((int) bi[21] & 0xff) << 8) | (int) bi[20] & 0xff;

// 对24位BMP进行解析

if (nBitCount == 24){

int nPad = (nSizeImage / nHeight) - nWidth * 3;

nData = new int[nHeight * nWidth];

nB=new int[nHeight * nWidth];

nR=new int[nHeight * nWidth];

nG=new int[nHeight * nWidth];

byte bRGB[] = new byte[(nWidth + nPad) * 3 * nHeight]; fs.read(bRGB, 0, (nWidth + nPad) * 3 * nHeight);

int nIndex = 0;

for (int j = 0; j < nHeight; j++){

for (int i = 0; i < nWidth; i++) {

nData[nWidth * (nHeight - j - 1) + i] = (255 & 0xff) << 24

| (((int) bRGB[nIndex + 2] & 0xff) << 16) | (((int) bRGB[nIndex + 1] & 0xff) << 8)

| (int) bRGB[nIndex] &

0xff;

nB[nWidth * (nHeight - j - 1) + i]=(int) bRGB[nIndex]& 0xff;

nG[nWidth * (nHeight - j - 1) + i]=(int) bRGB[nIndex+1]& 0xff;

nR[nWidth * (nHeight - j - 1) + i]=(int) bRGB[nIndex+2]& 0xff;

nIndex += 3;

}

nIndex += nPad;

}

// Toolkit kit = Toolkit.getDefaultToolkit();

// image = kit.createImage(new MemoryImageSource(nWidth, nHeight,

// nData, 0, nWidth));

/*

//调试数据的读取

FileWriter fw = new FileWriter("C://Documents and Settings//Administrator//My Documents//nDataRaw.txt");//创建新文件

PrintWriter out = new PrintWriter(fw);

for(int j=0;j

for(int i=0;i

out.print((65536*256+nData[nWidth * (nHeight - j - 1) + i])+"_"

+nR[nWidth * (nHeight - j - 1) + i]+"_"

+nG[nWidth * (nHeight - j - 1) + i]+"_"

+nB[nWidth * (nHeight - j - 1) + i]+" ");

}

out.println("");

}

out.close();

*/