1 /*
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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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8  * particular file as subject to the "Classpath" exception as provided
9  * by Oracle in the LICENSE file that accompanied this code.
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12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
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25 package com.sun.imageio.plugins.tiff;
26 
27 import java.io.IOException;
28 
29 public class TIFFLSBDecompressor extends TIFFDecompressor {
30 
31     /**
32      * Table for flipping bytes from LSB-to-MSB to MSB-to-LSB.
33      */
34     private static final byte[] flipTable = TIFFFaxDecompressor.flipTable;
35 
TIFFLSBDecompressor()36     public TIFFLSBDecompressor() {}
37 
decodeRaw(byte[] b, int dstOffset, int bitsPerPixel, int scanlineStride)38     public void decodeRaw(byte[] b,
39                           int dstOffset,
40                           int bitsPerPixel,
41                           int scanlineStride) throws IOException {
42         stream.seek(offset);
43 
44         int bytesPerRow = (srcWidth*bitsPerPixel + 7)/8;
45         if(bytesPerRow == scanlineStride) {
46             int numBytes = bytesPerRow*srcHeight;
47             stream.readFully(b, dstOffset, numBytes);
48             int xMax = dstOffset + numBytes;
49             for (int x = dstOffset; x < xMax; x++) {
50                 b[x] = flipTable[b[x]&0xff];
51             }
52         } else {
53             for (int y = 0; y < srcHeight; y++) {
54                 stream.readFully(b, dstOffset, bytesPerRow);
55                 int xMax = dstOffset + bytesPerRow;
56                 for (int x = dstOffset; x < xMax; x++) {
57                     b[x] = flipTable[b[x]&0xff];
58                 }
59                 dstOffset += scanlineStride;
60             }
61         }
62     }
63 }
64