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copied!<p>I've used this class many times to convert diferent bitmaps to bufferedimages</p> <pre><code>import java.awt.image.BufferedImage; import java.awt.image.DataBufferByte; import java.awt.image.DataBufferInt; import java.io.IOException; import java.io.InputStream; /** * Utility class for loading windows bitmap files * <p> * Based on code from author Abdul Bezrati and Pepijn Van Eeckhoudt */ public class BitmapLoader { /** * Static method to load a bitmap file based on the filename passed in. * Based on the bit count, this method will either call the 8 or 24 bit * bitmap reader methods * * @param file The name of the bitmap file to read * @throws IOException * @return A BufferedImage of the bitmap */ public static BufferedImage loadBitmap(String file) throws IOException { BufferedImage image; InputStream input = null; try { input = ResourceRetriever.getResourceAsStream(file); int bitmapFileHeaderLength = 14; int bitmapInfoHeaderLength = 40; byte bitmapFileHeader[] = new byte[bitmapFileHeaderLength]; byte bitmapInfoHeader[] = new byte[bitmapInfoHeaderLength]; input.read(bitmapFileHeader, 0, bitmapFileHeaderLength); input.read(bitmapInfoHeader, 0, bitmapInfoHeaderLength); int nSize = bytesToInt(bitmapFileHeader, 2); int nWidth = bytesToInt(bitmapInfoHeader, 4); int nHeight = bytesToInt(bitmapInfoHeader, 8); int nBiSize = bytesToInt(bitmapInfoHeader, 0); int nPlanes = bytesToShort(bitmapInfoHeader, 12); int nBitCount = bytesToShort(bitmapInfoHeader, 14); int nSizeImage = bytesToInt(bitmapInfoHeader, 20); int nCompression = bytesToInt(bitmapInfoHeader, 16); int nColoursUsed = bytesToInt(bitmapInfoHeader, 32); int nXPixelsMeter = bytesToInt(bitmapInfoHeader, 24); int nYPixelsMeter = bytesToInt(bitmapInfoHeader, 28); int nImportantColours = bytesToInt(bitmapInfoHeader, 36); if (nBitCount == 24) { image = read24BitBitmap(nSizeImage, nHeight, nWidth, input); } else if (nBitCount == 8) { image = read8BitBitmap(nColoursUsed, nBitCount, nSizeImage, nWidth, nHeight, input); } else { System.out.println("Not a 24-bit or 8-bit Windows Bitmap, aborting..."); image = null; } } finally { try { if (input != null) input.close(); } catch (IOException e) { } } return image; } /** * Static method to read a 8 bit bitmap * * @param nColoursUsed Number of colors used * @param nBitCount The bit count * @param nSizeImage The size of the image in bytes * @param nWidth The width of the image * @param input The input stream corresponding to the image * @throws IOException * @return A BufferedImage of the bitmap */ private static BufferedImage read8BitBitmap(int nColoursUsed, int nBitCount, int nSizeImage, int nWidth, int nHeight, InputStream input) throws IOException { int nNumColors = (nColoursUsed > 0) ? nColoursUsed : (1 & 0xff) << nBitCount; if (nSizeImage == 0) { nSizeImage = ((((nWidth * nBitCount) + 31) & ~31) >> 3); nSizeImage *= nHeight; } int npalette[] = new int[nNumColors]; byte bpalette[] = new byte[nNumColors * 4]; readBuffer(input, bpalette); int nindex8 = 0; for (int n = 0; n < nNumColors; n++) { npalette[n] = (255 & 0xff) << 24 | (bpalette[nindex8 + 2] & 0xff) << 16 | (bpalette[nindex8 + 1] & 0xff) << 8 | (bpalette[nindex8 + 0] & 0xff); nindex8 += 4; } int npad8 = (nSizeImage / nHeight) - nWidth; BufferedImage bufferedImage = new BufferedImage(nWidth, nHeight, BufferedImage.TYPE_INT_ARGB); DataBufferInt dataBufferByte = ((DataBufferInt) bufferedImage.getRaster().getDataBuffer()); int[][] bankData = dataBufferByte.getBankData(); byte bdata[] = new byte[(nWidth + npad8) * nHeight]; readBuffer(input, bdata); nindex8 = 0; for (int j8 = nHeight - 1; j8 >= 0; j8--) { for (int i8 = 0; i8 < nWidth; i8++) { bankData[0][j8 * nWidth + i8] = npalette[((int) bdata[nindex8] & 0xff)]; nindex8++; } nindex8 += npad8; } return bufferedImage; } /** * Static method to read a 24 bit bitmap * * @param nSizeImage size of the image in bytes * @param nHeight The height of the image * @param nWidth The width of the image * @param input The input stream corresponding to the image * @throws IOException * @return A BufferedImage of the bitmap */ private static BufferedImage read24BitBitmap(int nSizeImage, int nHeight, int nWidth, InputStream input) throws IOException { int npad = (nSizeImage / nHeight) - nWidth * 3; if (npad == 4 || npad < 0) npad = 0; int nindex = 0; BufferedImage bufferedImage = new BufferedImage(nWidth, nHeight, BufferedImage.TYPE_4BYTE_ABGR); DataBufferByte dataBufferByte = ((DataBufferByte) bufferedImage.getRaster().getDataBuffer()); byte[][] bankData = dataBufferByte.getBankData(); byte brgb[] = new byte[(nWidth + npad) * 3 * nHeight]; readBuffer(input, brgb); for (int j = nHeight - 1; j >= 0; j--) { for (int i = 0; i < nWidth; i++) { int base = (j * nWidth + i) * 4; bankData[0][base] = (byte) 255; bankData[0][base + 1] = brgb[nindex]; bankData[0][base + 2] = brgb[nindex + 1]; bankData[0][base + 3] = brgb[nindex + 2]; nindex += 3; } nindex += npad; } return bufferedImage; } /** * Converts bytes to an int * * @param bytes An array of bytes * @param index * @returns A int representation of the bytes */ private static int bytesToInt(byte[] bytes, int index) { return (bytes[index + 3] & 0xff) << 24 | (bytes[index + 2] & 0xff) << 16 | (bytes[index + 1] & 0xff) << 8 | bytes[index + 0] & 0xff; } /** * Converts bytes to a short * * @param bytes An array of bytes * @param index * @returns A short representation of the bytes */ private static short bytesToShort(byte[] bytes, int index) { return (short) (((bytes[index + 1] & 0xff) << 8) | (bytes[index + 0] & 0xff)); } /** * Reads the buffer * * @param in An InputStream * @param buffer An array of bytes * @throws IOException */ private static void readBuffer(InputStream in, byte[] buffer) throws IOException { int bytesRead = 0; int bytesToRead = buffer.length; while (bytesToRead > 0) { int read = in.read(buffer, bytesRead, bytesToRead); bytesRead += read; bytesToRead -= read; } } } </code></pre>

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