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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 09:22:09 +0000 |
| commit | 43a97878ce14b72f0981164f87f2e35e14151312 (patch) | |
| tree | 620249daf56c0258faa40cbdcf9cfba06de2a846 /other-licenses/7zstub/src/Java/SevenZip/Compression/RangeCoder/Decoder.java | |
| parent | Initial commit. (diff) | |
| download | firefox-upstream.tar.xz firefox-upstream.zip | |
Adding upstream version 110.0.1.upstream/110.0.1upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'other-licenses/7zstub/src/Java/SevenZip/Compression/RangeCoder/Decoder.java')
| -rw-r--r-- | other-licenses/7zstub/src/Java/SevenZip/Compression/RangeCoder/Decoder.java | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/Java/SevenZip/Compression/RangeCoder/Decoder.java b/other-licenses/7zstub/src/Java/SevenZip/Compression/RangeCoder/Decoder.java new file mode 100644 index 0000000000..7453383483 --- /dev/null +++ b/other-licenses/7zstub/src/Java/SevenZip/Compression/RangeCoder/Decoder.java @@ -0,0 +1,88 @@ +package SevenZip.Compression.RangeCoder;
+import java.io.IOException;
+
+public class Decoder
+{
+ static final int kTopMask = ~((1 << 24) - 1);
+
+ static final int kNumBitModelTotalBits = 11;
+ static final int kBitModelTotal = (1 << kNumBitModelTotalBits);
+ static final int kNumMoveBits = 5;
+
+ int Range;
+ int Code;
+
+ java.io.InputStream Stream;
+
+ public final void SetStream(java.io.InputStream stream)
+ {
+ Stream = stream;
+ }
+
+ public final void ReleaseStream()
+ {
+ Stream = null;
+ }
+
+ public final void Init() throws IOException
+ {
+ Code = 0;
+ Range = -1;
+ for (int i = 0; i < 5; i++)
+ Code = (Code << 8) | Stream.read();
+ }
+
+ public final int DecodeDirectBits(int numTotalBits) throws IOException
+ {
+ int result = 0;
+ for (int i = numTotalBits; i != 0; i--)
+ {
+ Range >>>= 1;
+ int t = ((Code - Range) >>> 31);
+ Code -= Range & (t - 1);
+ result = (result << 1) | (1 - t);
+
+ if ((Range & kTopMask) == 0)
+ {
+ Code = (Code << 8) | Stream.read();
+ Range <<= 8;
+ }
+ }
+ return result;
+ }
+
+ public int DecodeBit(short []probs, int index) throws IOException
+ {
+ int prob = probs[index];
+ int newBound = (Range >>> kNumBitModelTotalBits) * prob;
+ if ((Code ^ 0x80000000) < (newBound ^ 0x80000000))
+ {
+ Range = newBound;
+ probs[index] = (short)(prob + ((kBitModelTotal - prob) >>> kNumMoveBits));
+ if ((Range & kTopMask) == 0)
+ {
+ Code = (Code << 8) | Stream.read();
+ Range <<= 8;
+ }
+ return 0;
+ }
+ else
+ {
+ Range -= newBound;
+ Code -= newBound;
+ probs[index] = (short)(prob - ((prob) >>> kNumMoveBits));
+ if ((Range & kTopMask) == 0)
+ {
+ Code = (Code << 8) | Stream.read();
+ Range <<= 8;
+ }
+ return 1;
+ }
+ }
+
+ public static void InitBitModels(short []probs)
+ {
+ for (int i = 0; i < probs.length; i++)
+ probs[i] = (kBitModelTotal >>> 1);
+ }
+}
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