Directly on the code:
package org.bruce.vertices.asist.utils;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.MemoryImageSource;
import java.io.File;
import java.io.FileInputStream;
/**
* @author Bruce Yang
*
*/
public class BitmapPaser {
/**
* loadbitmap() method converted from Windows C code. Reads only
* uncompressed 24- and 8-bit images. Tested with images saved using
* Microsoft Paint in Windows 95. If the image is not a 24- or 8-bit image,
* the program refuses to even try. I guess one could include 4-bit images
* by masking the byte by first 1100 and then 0011. I am not really
* interested in such images. If a compressed image is attempted, the
* routine will probably fail by generating an IOException. Look for
* variable ncompression to be different from 0 to indicate compression is
* present.
*
* Arguments: sdir and sfile are the result of the FileDialog()
* getDirectory() and getFile() methods.
*
* Returns: Image Object, be sure to check for (Image)null !!!!
*/
public static Image loadbitmap(File imgFile) {
Image image;
System.out.println("loading:" + imgFile.getName());
try {
FileInputStream fis = new FileInputStream(imgFile);
int bflen = 14; // 14 byte BITMAPFILEHEADER
byte bf[] = new byte[bflen];
fis.read(bf, 0, bflen);
int bilen = 40; // 40-byte BITMAPINFOHEADER
byte bi[] = new byte[bilen];
fis.read(bi, 0, bilen);
// Interperet data.
int nsize = (((int) bf[5] & 0xff) << 24)
| (((int) bf[4] & 0xff) << 16)
| (((int) bf[3] & 0xff) << 8) | (int) bf[2] & 0xff;
System.out.println("File type is :" + (char) bf[0] + (char) bf[1]);
System.out.println("Size of file is :" + nsize);
// Head info data
int nbisize = (((int) bi[3] & 0xff) << 24)
| (((int) bi[2] & 0xff) << 16)
| (((int) bi[1] & 0xff) << 8) | (int) bi[0] & 0xff;
System.out.println("Size of bitmapinfoheader is :" + nbisize);
int nwidth = (((int) bi[7] & 0xff) << 24)
| (((int) bi[6] & 0xff) << 16)
| (((int) bi[5] & 0xff) << 8) | (int) bi[4] & 0xff;
System.out.println("Width is :" + nwidth);
int nheight = (((int) bi[11] & 0xff) << 24)
| (((int) bi[10] & 0xff) << 16)
| (((int) bi[9] & 0xff) << 8) | (int) bi[8] & 0xff;
System.out.println("Height is :" + nheight);
// number of planes in this bitmap
int nplanes = (((int) bi[13] & 0xff) << 8) | (int) bi[12] & 0xff;
System.out.println("Planes is :" + nplanes);
// bits per pixel used to store palette entry
// information. this also identifies in an indirect way
// the number of possible colors. possible values are: 1, 4, 8, 16,
// 24, 32
int nbitcount = (((int) bi[15] & 0xff) << 8) | (int) bi[14] & 0xff;
System.out.println("BitCount is :" + nbitcount);
// Look for non-zero values to indicate compression
int ncompression = (((int) bi[19]) << 24) | (((int) bi[18]) << 16)
| (((int) bi[17]) << 8) | (int) bi[16];
System.out.println("Compression is :" + ncompression);
int nsizeimage = (((int) bi[23] & 0xff) << 24)
| (((int) bi[22] & 0xff) << 16)
| (((int) bi[21] & 0xff) << 8) | (int) bi[20] & 0xff;
System.out.println("SizeImage is :" + nsizeimage);
int nxpm = (((int) bi[27] & 0xff) << 24)
| (((int) bi[26] & 0xff) << 16)
| (((int) bi[25] & 0xff) << 8) | (int) bi[24] & 0xff;
System.out.println("X-Pixels per meter is :" + nxpm);
int nypm = (((int) bi[31] & 0xff) << 24)
| (((int) bi[30] & 0xff) << 16)
| (((int) bi[29] & 0xff) << 8) | (int) bi[28] & 0xff;
System.out.println("Y-Pixels per meter is :" + nypm);
int nclrused = (((int) bi[35] & 0xff) << 24)
| (((int) bi[34] & 0xff) << 16)
| (((int) bi[33] & 0xff) << 8) | (int) bi[32] & 0xff;
System.out.println("Colors used are :" + nclrused);
int nclrimp = (((int) bi[39] & 0xff) << 24)
| (((int) bi[38] & 0xff) << 16)
| (((int) bi[37] & 0xff) << 8) | (int) bi[36] & 0xff;
System.out.println("Colors important are :" + nclrimp);
// Some bitmaps do not have the sizeimage field calculated
// Ferret out these cases and fix 'em.
if (nsizeimage == 0) {
nsizeimage = ((((nwidth * nbitcount) + 31) & ~31) >> 3);
nsizeimage *= nheight;
System.out.println("nsizeimage (backup) is" + nsizeimage);
}
if (nbitcount == 32) {
// No Palatte data for 32-bit format but scan lines are
// padded out to even 4-byte boundaries.
int npad = (nsizeimage / nheight) - nwidth * 4;
int ndata[] = new int[nheight * nwidth];
byte brgb[] = new byte[(nwidth + npad) * 4 * nheight];
fis.read(brgb, 0, (nwidth + npad) * 4 * 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;
/*
* System.out.println("Encoded Color at (" + i + "," + j
* + ")is:" + brgb + " (R,G,B)= (" + ( (int) (brgb[2]) &
* 0xff) + "," + ( (int) brgb[1] & 0xff) + "," + ( (int)
* brgb[0] & 0xff) + ")");
*/
nindex += 4;
}
nindex += npad;
}
image = Toolkit.getDefaultToolkit().createImage(
new MemoryImageSource(nwidth, nheight, ndata, 0, nwidth));
} else if (nbitcount == 24) {
// No Palatte data for 24-bit format but scan lines are
// padded out to even 4-byte boundaries.
int npad = (nsizeimage / nheight) - nwidth * 3;
int ndata[] = new int[nheight * nwidth];
byte brgb[] = new byte[(nwidth + npad) * 3 * nheight];
fis.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;
/*
* System.out.println("Encoded Color at (" + i + "," + j
* + ")is:" + brgb + " (R,G,B)= (" + ( (int) (brgb[2]) &
* 0xff) + "," + ( (int) brgb[1] & 0xff) + "," + ( (int)
* brgb[0] & 0xff) + ")");
*/
nindex += 3;
}
nindex += npad;
}
image = Toolkit.getDefaultToolkit().createImage(
new MemoryImageSource(nwidth, nheight, ndata, 0, nwidth));
} else if (nbitcount == 16) {
// No Palatte data for 16-bit format but scan lines are
// padded out to even 4-byte boundaries.
int npad = (nsizeimage / nheight) - nwidth * 2;
int ndata[] = new int[nheight * nwidth];
byte brgb[] = new byte[(nwidth + npad) * 2 * nheight];
fis.read(brgb, 0, (nwidth + npad) * 2 * 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 + 1] >>> 2) & 0x3f) | 0x60) << 3 << 16)
| ((((int) (((brgb[nindex + 1] & 0x3) << 3) | ((brgb[nindex] & 0xe0) >>> 5))) | 0x60) << 3 << 8)
| ((((int) brgb[nindex] & 0x1f) | 0x60) << 3);
nindex += 2;
}
nindex += npad;
}
image = Toolkit.getDefaultToolkit().createImage(
new MemoryImageSource(nwidth, nheight, ndata, 0, nwidth));
} else if (nbitcount == 8) {
// Have to determine the number of colors, the clrsused
// parameter is dominant if it is greater than zero. If
// zero1, calculate colors based on bitsperpixel.
int nNumColors = 0;
if (nclrused > 0) {
nNumColors = nclrused;
} else {
nNumColors = (1 & 0xff) << nbitcount;
}
System.out.println("The number of Colors is" + nNumColors);
// Read the palatte colors.
int npalette[] = new int[nNumColors];
byte bpalette[] = new byte[nNumColors * 4];
fis.read(bpalette, 0, nNumColors * 4);
int nindex8 = 0;
for (int n = 0; n < nNumColors; n++) {
npalette[n] = (255 & 0xff) << 24
| (((int) bpalette[nindex8 + 2] & 0xff) << 16)
| (((int) bpalette[nindex8 + 1] & 0xff) << 8)
| (int) bpalette[nindex8] & 0xff;
/*
* System.out.println("Palette Color " + n + " is:" +
* npalette[n] + " (res,R,G,B)= (" + ( (int)
* (bpalette[nindex8 + 3]) & 0xff) + "," + ( (int)
* (bpalette[nindex8 + 2]) & 0xff) + "," + ( (int)
* bpalette[nindex8 + 1] & 0xff) + "," + ( (int)
* bpalette[nindex8] & 0xff) + ")");
*/
nindex8 += 4;
}
// Read the image data (actually indices into the palette)
// Scan lines are still padded out to even 4-byte
// boundaries.
int npad8 = (nsizeimage / nheight) - nwidth;
System.out.println("nPad is:" + npad8);
int ndata8[] = new int[nwidth * nheight];
byte bdata[] = new byte[(nwidth + npad8) * nheight];
fis.read(bdata, 0, (nwidth + npad8) * nheight);
nindex8 = 0;
for (int j8 = 0; j8 < nheight; j8++) {
for (int i8 = 0; i8 < nwidth; i8++) {
ndata8[nwidth * (nheight - j8 - 1) + i8] = npalette[((int) bdata[nindex8] & 0xff)];
nindex8++;
}
nindex8 += npad8;
}
image = Toolkit.getDefaultToolkit().createImage(
new MemoryImageSource(nwidth, nheight, ndata8, 0, nwidth));
} else if (nbitcount == 4) {
// Have to determine the number of colors, the clrsused
// parameter is dominant if it is greater than zero. If
// zero1, calculate colors based on bitsperpixel.
int nNumColors = 0;
if (nclrused > 0) {
nNumColors = nclrused;
} else {
nNumColors = (1 & 0xff) << nbitcount;
}
System.out.println("The number of Colors is" + nNumColors);
// Read the palatte colors.
int npalette[] = new int[nNumColors];
byte bpalette[] = new byte[nNumColors * 4];
fis.read(bpalette, 0, nNumColors * 4);
int nindex4 = 0;
for (int n = 0; n < nNumColors; n++) {
npalette[n] = (255 & 0xff) << 24
| (((int) bpalette[nindex4 + 2] & 0xff) << 16)
| (((int) bpalette[nindex4 + 1] & 0xff) << 8)
| (int) bpalette[nindex4] & 0xff;
/*
* System.out.println("Palette Color " + n + " is:" +
* npalette[n] + " (res,R,G,B)= (" + ( (int)
* (bpalette[nindex8 + 3]) & 0xff) + "," + ( (int)
* (bpalette[nindex8 + 2]) & 0xff) + "," + ( (int)
* bpalette[nindex8 + 1] & 0xff) + "," + ( (int)
* bpalette[nindex8] & 0xff) + ")");
*/
nindex4 += 4;
}
// Scan line is padded with zeroes to be a multiple of four
// bytes
int scanLineSize = (((nwidth * nbitcount) + 31) & ~31) >> 3;
// Read the image data (actually indices into the palette)
// Scan lines are still padded out to even 4-byte
// boundaries.
// int npad4 = (nsizeimage / nheight) - nwidth / 2;
/*
* int npad4 = 0; if ((nwidth%2) == 0) npad4 = scanLineSize -
* nwidth/2; else npad4 = scanLineSize - nwidth/2 - 1;
* System.out.println("nPad is:" + npad4);
*/
int ndata4[] = new int[nwidth * nheight];
// byte bdata[] = new byte[ scanLineSize * nheight];
byte blinedata[] = new byte[scanLineSize];
// fs.read(bdata, 0, scanLineSize * nheight);
nindex4 = 0;
for (int j4 = 0; j4 < nheight; j4++) {
fis.read(blinedata, 0, scanLineSize);
nindex4 = 0;
for (int i4 = 0; i4 < nwidth; i4++) {
if (nwidth * (nheight - j4 - 1) + i4 > nwidth * nheight - 1) {
break;
}
if (nindex4 > scanLineSize * nheight - 1) {
break;
}
for (int pixPerByte = 0; pixPerByte < 2; pixPerByte++) {
if (pixPerByte == 0) {
ndata4[nwidth * (nheight - j4 - 1) + i4] = npalette[((int) (blinedata[nindex4] >> 4) & 0xf)];
i4 ++;
if (i4 >= nwidth) {
break;
}
} else {
ndata4[nwidth * (nheight - j4 - 1) + i4] = npalette[((int) blinedata[nindex4] & 0xf)];
}
}
nindex4 ++;
}
}
image = Toolkit.getDefaultToolkit().createImage(
new MemoryImageSource(nwidth, nheight, ndata4, 0, nwidth));
} else if (nbitcount == 1) {
// Have to determine the number of colors, the clrsused
// parameter is dominant if it is greater than zero. If
// zero1, calculate colors based on bitsperpixel.
int nNumColors = 0;
if (nclrused > 0) {
nNumColors = nclrused;
} else {
nNumColors = (1 & 0xff) << nbitcount;
}
System.out.println("The number of Colors is" + nNumColors);
// Read the palatte colors.
int npalette[] = new int[nNumColors];
byte bpalette[] = new byte[nNumColors * 4];
fis.read(bpalette, 0, nNumColors * 4);
int nindex1 = 0;
for (int n = 0; n < nNumColors; n++) {
npalette[n] = (255 & 0xff) << 24
| (((int) bpalette[nindex1 + 2] & 0xff) << 16)
| (((int) bpalette[nindex1 + 1] & 0xff) << 8)
| (int) bpalette[nindex1] & 0xff;
nindex1 += 4;
}
// Scan line is padded with zeroes to be a multiple of four
// bytes
int scanLineSize = (((nwidth * nbitcount) + 31) & ~31) >> 3;
int ndata1[] = new int[nwidth * nheight];
// byte bdata[] = new byte[ scanLineSize * nheight];
byte blinedata[] = new byte[scanLineSize];
// fs.read(bdata, 0, scanLineSize * nheight);
nindex1 = 0;
for (int j1 = 0; j1 < nheight; j1++) {
fis.read(blinedata, 0, scanLineSize);
nindex1 = 0;
for (int i1 = 0; i1 < nwidth; i1++) {
if (nwidth * (nheight - j1 - 1) + i1 > nwidth * nheight - 1) {
break;
}
if (nindex1 > scanLineSize * nheight - 1) {
break;
}
for (int pixPerByte = 0; pixPerByte < 8; pixPerByte++) {
int shift = 8 - pixPerByte - 1;
ndata1[nwidth * (nheight - j1 - 1) + i1] = npalette[((int) (blinedata[nindex1] >> shift) & 0x1)];
if (pixPerByte != 7) {
i1 ++;
if (i1 >= nwidth) {
break;
}
}
}
nindex1 ++;
}
}
image = Toolkit.getDefaultToolkit().createImage(
new MemoryImageSource(nwidth, nheight, ndata1, 0, nwidth));
} else {
System.out.println("Not a 32-bit, 24-bit, 16-bit, 8-bit, 4-bit and 1-bit Windows Bitmap, aborting...");
image = (Image) null;
}
fis.close();
return image;
} catch (Exception e) {
e.printStackTrace();
System.out.println("Caught exception in loadbitmap!");
}
return (Image) null;
}
}Reproduced in: https: //www.cnblogs.com/yang3wei/archive/2012/07/07/2739683.html