// same as SubsampleBinaryToGray, and change byteLoop to protected in superclass?
// extends that and save this? using prote
private void byteLoop(Raster source, WritableRaster dest, Rectangle destRect) {
PixelAccessor pa = new PixelAccessor(source.getSampleModel(), null);
PackedImageData pid = pa.getPackedPixels(source, source.getBounds(), false, false);
byte[] sourceData = pid.data;
int sourceDBOffset = pid.offset;
int dx = destRect.x;
int dy = destRect.y;
int dwi = destRect.width;
int dhi = destRect.height;
int sourceTransX = pid.rect.x; // source.getSampleModelTranslateX();
int sourceTransY = pid.rect.y; // source.getSampleModelTranslateY();
int sourceDataBitOffset = pid.bitOffset;
int sourceScanlineStride = pid.lineStride;
PixelInterleavedSampleModel destSM = (PixelInterleavedSampleModel) dest.getSampleModel();
DataBufferByte destDB = (DataBufferByte) dest.getDataBuffer();
int destTransX = dest.getSampleModelTranslateX();
int destTransY = dest.getSampleModelTranslateY();
int destScanlineStride = destSM.getScanlineStride();
byte[] destData = destDB.getData();
int destDBOffset = destDB.getOffset();
int[] sbytenum = new int[dwi];
int[] sstartbit = new int[dwi];
int[] sAreaBitsOn = new int[dwi];
for (int i = 0; i < dwi; i++) {
int x = xValues[dx + i];
int sbitnum = sourceDataBitOffset + (x - sourceTransX);
sbytenum[i] = sbitnum >> 3;
sstartbit[i] = sbitnum % 8;
}
for (int j = 0; j < dhi; j++) {
for (int i = 0; i < dwi; i++) {
sAreaBitsOn[i] = 0;
}
for (int y = yValues[dy + j]; y < yValues[dy + j] + blockY; y++) {
int sourceYOffset = (y - sourceTransY) * sourceScanlineStride + sourceDBOffset;
int delement, selement, sendbiti, sendbytenumi;
for (int i = 0; i < dwi; i++) {
delement = 0;
sendbiti = sstartbit[i] + blockX - 1;
sendbytenumi = sbytenum[i] + (sendbiti >> 3); // byte num of the end bit
sendbiti %= 8; // true src end bit position
selement = 0x00ff & (int) sourceData[sourceYOffset + sbytenum[i]];
int swingBits = 24 + sstartbit[i];
if (sbytenum[i] == sendbytenumi) {
// selement <<= 24 + sstartbit[i];
selement <<= swingBits;
selement >>>= 31 - sendbiti + sstartbit[i];
delement += lut[selement];
} else {
selement <<= swingBits;
selement >>>= swingBits;
// selement >>>= 24;
delement += lut[selement];
for (int b = sbytenum[i] + 1; b < sendbytenumi; b++) {
selement = 0x00ff & (int) sourceData[sourceYOffset + b];
delement += lut[selement];
}
selement = 0x00ff & (int) sourceData[sourceYOffset + sendbytenumi];
selement >>>= 7 - sendbiti;
delement += lut[selement];
}
sAreaBitsOn[i] += delement;
}
}
int destYOffset = (j + dy - destTransY) * destScanlineStride + destDBOffset;
destYOffset += dx - destTransX;
// update dest values for row j in raster
for (int i = 0; i < dwi; i++) {
destData[destYOffset + i] = lutGray[sAreaBitsOn[i]];
}
}
}
// speed up for the case of 4x4
// and data buffer bitOffset is 0 or 4
private void byteLoop4x4(Raster source, WritableRaster dest, Rectangle destRect) {
PixelAccessor pa = new PixelAccessor(source.getSampleModel(), null);
PackedImageData pid = pa.getPackedPixels(source, source.getBounds(), false, false);
if (pid.bitOffset % 4 != 0) {
// special treatment only for offsets 0 and 4
byteLoop(source, dest, destRect);
return;
}
byte[] sourceData = pid.data;
int sourceDBOffset = pid.offset;
int dx = destRect.x;
int dy = destRect.y;
int dwi = destRect.width;
int dhi = destRect.height;
int sourceTransX = pid.rect.x; // source.getSampleModelTranslateX();
int sourceTransY = pid.rect.y; // source.getSampleModelTranslateY();
int sourceDataBitOffset = pid.bitOffset;
int sourceScanlineStride = pid.lineStride;
PixelInterleavedSampleModel destSM = (PixelInterleavedSampleModel) dest.getSampleModel();
DataBufferByte destDB = (DataBufferByte) dest.getDataBuffer();
int destTransX = dest.getSampleModelTranslateX();
int destTransY = dest.getSampleModelTranslateY();
int destScanlineStride = destSM.getScanlineStride();
byte[] destData = destDB.getData();
int destDBOffset = destDB.getOffset();
int[] sAreaBitsOn = new int[2];
for (int j = 0; j < dhi; j++) {
int y = (dy + j) << 2; // int y = (dy + j) * blockY;
int sourceYOffset = (y - sourceTransY) * sourceScanlineStride + sourceDBOffset;
int destYOffset = (j + dy - destTransY) * destScanlineStride + destDBOffset;
destYOffset += dx - destTransX;
int selement, sbitnumi, sstartbiti, sbytenumi;
// sbitnumi - the 1st bit position from the minX of the raster
// sstartbiti - the 1st bit position in the byte data
// sbitnumi = blockX * dx - sourceTransX + sourceDataBitOffset;
sbitnumi = (dx << 2) - sourceTransX + sourceDataBitOffset;
for (int i = 0; i < dwi; ) {
sbytenumi = sbitnumi >> 3;
sstartbiti = sbitnumi % 8;
int byteindex = sourceYOffset + sbytenumi;
sAreaBitsOn[0] = sAreaBitsOn[1] = 0;
for (int k = 0; k < 4; k++, byteindex += sourceScanlineStride) {
selement = 0x00ff & (int) sourceData[byteindex];
sAreaBitsOn[1] += lut[selement & 0x000f];
sAreaBitsOn[0] += lut[selement >> 4];
}
// set dest elements
// count in 4s
// sstartbiti = 0 means the 0th of sAreaBitsOn is added to
// current dest position, ie destYOffset + i;
// sstartbiti = 4 means the 1th of sAreaBitsOn is added to
// current dest position, ie destYOffset + i;
// sstartbiti now means different
// sstartbiti = sstartbiti / 4;
sstartbiti >>= 2;
while (sstartbiti < 2 && i < dwi) {
destData[destYOffset + i] = lutGray[sAreaBitsOn[sstartbiti]];
sstartbiti++;
i++;
sbitnumi += blockX;
}
}
}
}