diff options
Diffstat (limited to 'org.fox.ttcomics/src/main/java/com/github/junrar/unpack/ppm/RangeCoder.java')
| -rw-r--r-- | org.fox.ttcomics/src/main/java/com/github/junrar/unpack/ppm/RangeCoder.java | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/org.fox.ttcomics/src/main/java/com/github/junrar/unpack/ppm/RangeCoder.java b/org.fox.ttcomics/src/main/java/com/github/junrar/unpack/ppm/RangeCoder.java new file mode 100644 index 0000000..734813f --- /dev/null +++ b/org.fox.ttcomics/src/main/java/com/github/junrar/unpack/ppm/RangeCoder.java @@ -0,0 +1,177 @@ +/*
+ * Copyright (c) 2007 innoSysTec (R) GmbH, Germany. All rights reserved.
+ * Original author: Edmund Wagner
+ * Creation date: 31.05.2007
+ *
+ * Source: $HeadURL$
+ * Last changed: $LastChangedDate$
+ *
+ * the unrar licence applies to all junrar source and binary distributions
+ * you are not allowed to use this source to re-create the RAR compression algorithm
+ *
+ * Here some html entities which can be used for escaping javadoc tags:
+ * "&": "&" or "&"
+ * "<": "<" or "<"
+ * ">": ">" or ">"
+ * "@": "@"
+ */
+package com.github.junrar.unpack.ppm;
+
+import java.io.IOException;
+
+import com.github.junrar.exception.RarException;
+import com.github.junrar.unpack.Unpack;
+
+
+/**
+ * DOCUMENT ME
+ *
+ * @author $LastChangedBy$
+ * @version $LastChangedRevision$
+ */
+public class RangeCoder
+{
+ public static final int TOP = 1 << 24;
+
+ public static final int BOT = 1 << 15;
+
+ private static final long uintMask = 0xFFFFffffL;
+
+ // uint low, code, range;
+ private long low, code, range;
+
+ private final SubRange subRange = new SubRange();
+
+ private Unpack unpackRead;
+
+ public SubRange getSubRange()
+ {
+ return subRange;
+ }
+
+ public void initDecoder(Unpack unpackRead) throws IOException, RarException
+ {
+ this.unpackRead = unpackRead;
+
+ low = code = 0L;
+ range = 0xFFFFffffL;
+ for (int i = 0; i < 4; i++) {
+ code = ((code << 8) | getChar())&uintMask;
+ }
+ }
+
+ public int getCurrentCount()
+ {
+ range = (range / subRange.getScale())&uintMask;
+ return (int)((code - low) / (range));
+ }
+
+ public long getCurrentShiftCount(int SHIFT)
+ {
+ range = range >>>SHIFT;
+ return ((code - low) / (range))&uintMask;
+ }
+
+ public void decode()
+ {
+ low = (low + (range * subRange.getLowCount()))&uintMask;
+ range = (range * (subRange.getHighCount() - subRange.getLowCount()))&uintMask;
+ }
+
+ private int getChar() throws IOException, RarException
+ {
+ return (unpackRead.getChar());
+ }
+
+ public void ariDecNormalize() throws IOException, RarException
+ {
+// while ((low ^ (low + range)) < TOP || range < BOT && ((range = -low & (BOT - 1)) != 0 ? true : true))
+// {
+// code = ((code << 8) | unpackRead.getChar()&0xff)&uintMask;
+// range = (range << 8)&uintMask;
+// low = (low << 8)&uintMask;
+// }
+
+ // Rewrote for clarity
+ boolean c2 = false;
+ while ((low ^ (low + range)) < TOP || (c2 = range < BOT)) {
+ if (c2) {
+ range = (-low & (BOT - 1))&uintMask;
+ c2 = false;
+ }
+ code = ((code << 8) | getChar())&uintMask;
+ range = (range << 8)&uintMask;
+ low = (low << 8)&uintMask;
+ }
+ }
+
+ // Debug
+ public String toString() {
+ StringBuilder buffer = new StringBuilder();
+ buffer.append("RangeCoder[");
+ buffer.append("\n low=");
+ buffer.append(low);
+ buffer.append("\n code=");
+ buffer.append(code);
+ buffer.append("\n range=");
+ buffer.append(range);
+ buffer.append("\n subrange=");
+ buffer.append(subRange);
+ buffer.append("]");
+ return buffer.toString();
+ }
+
+ public static class SubRange
+ {
+ // uint LowCount, HighCount, scale;
+ private long lowCount, highCount, scale;
+
+ public long getHighCount()
+ {
+ return highCount;
+ }
+
+ public void setHighCount(long highCount)
+ {
+ this.highCount = highCount&uintMask;
+ }
+
+ public long getLowCount()
+ {
+ return lowCount&uintMask;
+ }
+
+ public void setLowCount(long lowCount)
+ {
+ this.lowCount = lowCount&uintMask;
+ }
+
+ public long getScale()
+ {
+ return scale;
+ }
+
+ public void setScale(long scale)
+ {
+ this.scale = scale&uintMask;
+ }
+
+ public void incScale(int dScale) {
+ setScale(getScale() + dScale);
+ }
+
+ // Debug
+ public String toString() {
+ StringBuilder buffer = new StringBuilder();
+ buffer.append("SubRange[");
+ buffer.append("\n lowCount=");
+ buffer.append(lowCount);
+ buffer.append("\n highCount=");
+ buffer.append(highCount);
+ buffer.append("\n scale=");
+ buffer.append(scale);
+ buffer.append("]");
+ return buffer.toString();
+ }
+ }
+}
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