本文介紹了如何在BufferedImage中設置RGB像素以顯示16位深度的PNG？的處理方法，對大家解決問題具有一定的參考價值，需要的朋友們下面隨著小編來一起學習吧！
問題描述
我正在嘗試讀取并顯示PNG文件。
我可以輕松處理8位深度的圖像。
我按如下方式進行：
BufferedImage result = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
然后我讀取每個像素的3*8=24位，將它們保存在一個字節數組data中，并使用：
將它們放入圖像中
for (int y = 0; y < height; y++)
for (int x = 0; x < width; x++)
result.setRGB(x, y, ((data[x * 3 + 0] & 0xff) << 16)
+ ((data[x * 3 + 1] & 0xff) << 8)
+ ((data[x * 3 + 2] & 0xff)));
現在問題出在16位深度圖像上。當然，data現在更大了，它包含48位，分為6個字節，每個RGB三元組：來自調試器的data具有我期望的值。
如何設置RGB像素？我必須更改BufferedImage聲明嗎？可以使用：
BufferedImage result = new BufferedImage(width, height, BufferedImage.TYPE_USHORT_565_RGB);
提前表示感謝！
附注：按照PNG標準，圖像的顏色類型為2(不含Alpha的RGB)。
也許我將不得不使用http://docs.oracle.com/javase/7/docs/api/java/awt/image/ColorModel.html
推薦答案
@haraldK指向了正確的方向。我提供了一些來自”icafe”Java圖像庫的PNGReader的工作代碼。
if(bitsPerPixel == 16) {
if(interlace_method==NON_INTERLACED)
spixels = generate16BitRGBPixels(compr_data, false);
else {
spixels = generate16BitRGBInterlacedPixels(compr_data, false);
}
int[] off = {0, 1, 2}; //band offset, we have 3 bands
int numOfBands = 3;
boolean hasAlpha = false;
int trans = Transparency.OPAQUE;
int[] nBits = {16, 16, 16};
if(alpha != null) { // Deal with single color transparency
off = new int[] {0, 1, 2, 3}; //band offset, we have 4 bands
numOfBands = 4;
hasAlpha = true;
trans = Transparency.TRANSLUCENT;
nBits = new int[] {16, 16, 16, 16};
}
db = new DataBufferUShort(spixels, spixels.length);
raster = Raster.createInterleavedRaster(db, width, height, width*numOfBands, numOfBands, off, null);
cm = new ComponentColorModel(colorSpace, nBits, hasAlpha, false, trans, DataBuffer.TYPE_USHORT);
}
return new BufferedImage(cm, raster, false, null);
以下是Generate16BitRGBPixels()方法：
private short[] generate16BitRGBPixels(byte[] compr_data, boolean fullAlpha) throws Exception {
//
int bytesPerPixel = 0;
byte[] pixBytes;
if (fullAlpha)
bytesPerPixel = 8;
else
bytesPerPixel = 6;
bytesPerScanLine = width*bytesPerPixel;
// Now inflate the data.
pixBytes = new byte[height * bytesPerScanLine];
// Wrap an InflaterInputStream with a bufferedInputStream to speed up reading
BufferedInputStream bis = new BufferedInputStream(new InflaterInputStream(new ByteArrayInputStream(compr_data)));
apply_defilter(bis, pixBytes, height, bytesPerPixel, bytesPerScanLine);
short[] spixels = null;
if(alpha != null) { // Deal with single color transparency
spixels = new short[width*height*4];
short redMask = (short)((alpha[1]&0xff)|(alpha[0]&0xff)<<8);
short greenMask = (short)((alpha[3]&0xff)|(alpha[2]&0xff)<<8);;
short blueMask = (short)((alpha[5]&0xff)|(alpha[4]&0xff)<<8);
for(int i = 0, index = 0; i < pixBytes.length; index += 4) {
short red = (short)((pixBytes[i++]&0xff)<<8|(pixBytes[i++]&0xff));
short green = (short)((pixBytes[i++]&0xff)<<8|(pixBytes[i++]&0xff));
short blue = (short)((pixBytes[i++]&0xff)<<8|(pixBytes[i++]&0xff));
spixels[index] = red;
spixels[index + 1] = green;
spixels[index + 2] = blue;
if(spixels[index] == redMask && spixels[index + 1] == greenMask && spixels[index + 2] == blueMask) {
spixels[index + 3] = (short)0x0000;
} else {
spixels[index + 3] = (short)0xffff;
}
}
} else
spixels = ArrayUtils.toShortArray(pixBytes, true);
return spixels;
}
和ArrayUtils.toShortArray()方法：
public static short[] toShortArray(byte[] data, int offset, int len, boolean bigEndian) {
ByteBuffer byteBuffer = ByteBuffer.wrap(data, offset, len);
if (bigEndian) {
byteBuffer.order(ByteOrder.BIG_ENDIAN);
} else {
byteBuffer.order(ByteOrder.LITTLE_ENDIAN);
}
ShortBuffer shortBuf = byteBuffer.asShortBuffer();
short[] array = new short[shortBuf.remaining()];
shortBuf.get(array);
return array;
}
這篇關于如何在BufferedImage中設置RGB像素以顯示16位深度的PNG？的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，
