public static boolean equalsPixelData(File f1, File f2) throws IOException {
InputStream in1 = new BufferedInputStream(new FileInputStream(f1));
try {
InputStream in2 = new BufferedInputStream(new FileInputStream(f2));
try {
Dataset attrs = DcmObjectFactory.getInstance().newDataset();
DcmParserFactory pf = DcmParserFactory.getInstance();
DcmParser p1 = pf.newDcmParser(in1);
DcmParser p2 = pf.newDcmParser(in2);
p1.setDcmHandler(attrs.getDcmHandler());
p1.parseDcmFile(FileFormat.DICOM_FILE, Tags.PixelData);
p2.parseDcmFile(FileFormat.DICOM_FILE, Tags.PixelData);
int samples = attrs.getInt(Tags.SamplesPerPixel, 1);
int frames = attrs.getInt(Tags.NumberOfFrames, 1);
int rows = attrs.getInt(Tags.Rows, 1);
int columns = attrs.getInt(Tags.Columns, 1);
int bitsAlloc = attrs.getInt(Tags.BitsAllocated, 8);
int bitsStored = attrs.getInt(Tags.BitsStored, bitsAlloc);
int frameLength = rows * columns * samples * bitsAlloc / 8;
int pixelDataLength = frameLength * frames;
if (pixelDataLength > p1.getReadLength() || pixelDataLength > p2.getReadLength()) {
return false;
}
byte[] b1 = new byte[BUFFER_SIZE];
byte[] b2 = new byte[BUFFER_SIZE];
int[] mask = {0xff, 0xff};
int len, len2;
if (bitsAlloc == 16 && bitsStored < 16) {
mask[p1.getDcmDecodeParam().byteOrder == ByteOrder.LITTLE_ENDIAN ? 1 : 0] =
0xff >>> (16 - bitsStored);
}
int pos = 0;
while (pos < pixelDataLength) {
len = in1.read(b1, 0, Math.min(pixelDataLength - pos, BUFFER_SIZE));
if (len < 0) // EOF
return false;
int off = 0;
while (off < len) {
off += len2 = in2.read(b2, off, len - off);
if (len2 < 0) // EOF
return false;
}
for (int i = 0; i < len; i++, pos++)
if (((b1[i] - b2[i]) & mask[pos & 1]) != 0) return false;
}
return true;
} finally {
in2.close();
}
} finally {
in1.close();
}
}
public static int maxDiffPixelData(File f1, File f2) throws IOException {
int maxDiff = 0;
InputStream in1 = new BufferedInputStream(new FileInputStream(f1));
try {
InputStream in2 = new BufferedInputStream(new FileInputStream(f2));
try {
DcmObjectFactory df = DcmObjectFactory.getInstance();
DcmParserFactory pf = DcmParserFactory.getInstance();
Dataset attrs1 = df.newDataset();
Dataset attrs2 = df.newDataset();
DcmParser p1 = pf.newDcmParser(in1);
DcmParser p2 = pf.newDcmParser(in2);
p1.setDcmHandler(attrs1.getDcmHandler());
p2.setDcmHandler(attrs2.getDcmHandler());
p1.parseDcmFile(FileFormat.DICOM_FILE, Tags.PixelData);
p2.parseDcmFile(FileFormat.DICOM_FILE, Tags.PixelData);
int samples = attrs1.getInt(Tags.SamplesPerPixel, 1);
int frames = attrs1.getInt(Tags.NumberOfFrames, 1);
int rows = attrs1.getInt(Tags.Rows, 1);
int columns = attrs1.getInt(Tags.Columns, 1);
int bitsAlloc = attrs1.getInt(Tags.BitsAllocated, 8);
int bitsStored = attrs1.getInt(Tags.BitsStored, bitsAlloc);
int bitsStored2 = attrs2.getInt(Tags.BitsStored, bitsAlloc);
int pixelRepresentation1 = attrs1.getInt(Tags.PixelRepresentation, 0);
int pixelRepresentation2 = attrs2.getInt(Tags.PixelRepresentation, 0);
int frameLength = rows * columns * samples * bitsAlloc / 8;
int pixelDataLength = frameLength * frames;
if (pixelDataLength > p1.getReadLength() || pixelDataLength > p2.getReadLength()) {
return Integer.MAX_VALUE;
}
byte[] b1 = new byte[BUFFER_SIZE];
byte[] b2 = new byte[BUFFER_SIZE];
byte lsb1 = 0, lsb2 = 0;
int w1, w2, len, len2;
int bitmask1 = 0xffff >>> (bitsAlloc - bitsStored);
int bitmask2 = 0xffff >>> (bitsAlloc - bitsStored2);
int signed1 = pixelRepresentation1 != 0 ? (-1 & ~bitmask1) >> 1 : 0;
int signed2 = pixelRepresentation2 != 0 ? (-1 & ~bitmask2) >> 1 : 0;
int pos = 0;
while (pos < pixelDataLength) {
len = in1.read(b1, 0, Math.min(pixelDataLength - pos, BUFFER_SIZE));
if (len < 0) // EOF
return Integer.MAX_VALUE;
int off = 0;
while (off < len) {
off += len2 = in2.read(b2, off, len - off);
if (len2 < 0) // EOF
return Integer.MAX_VALUE;
}
if (bitsAlloc == 8)
for (int i = 0; i < len; i++, pos++)
maxDiff = Math.max(maxDiff, Math.abs((b1[i] & 0xff) - (b2[i] & 0xff)));
else {
for (int i = 0; i < len; i++, pos++)
// TODO assumes LE Byte Order
if ((pos & 1) == 0) {
lsb1 = b1[i];
lsb2 = b2[i];
} else {
if (((w1 = ((b1[i] << 8) | (lsb1 & 0xff)) & bitmask1) & signed1) != 0)
w1 |= signed1;
if (((w2 = ((b2[i] << 8) | (lsb2 & 0xff)) & bitmask2) & signed2) != 0)
w2 |= signed2;
maxDiff = Math.max(maxDiff, Math.abs(w1 - w2));
}
}
}
return maxDiff;
} finally {
in2.close();
}
} finally {
in1.close();
}
}
