--- a/sources/huffman/huffcodec.h Fri May 15 20:10:44 2015 +0300
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,182 +0,0 @@
-/*
- * skulltag::HuffmanCodec class - Huffman encoder and decoder.
- *
- * Copyright 2009 Timothy Landers
- * email: code.vortexcortex@gmail.com
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-#ifndef _HUFFMAN_CODEC_VERSION
-#define _HUFFMAN_CODEC_VERSION 1
-#define _HUFFMAN_CODEC_REV 0
-
-#include "codec.h"
-#include "bitwriter.h"
-#include "bitreader.h"
-
-/** Prevents naming convention problems via encapsulation. */
-namespace skulltag {
-
- /** HuffmanCodec class - Encodes and Decodes data using a Huffman tree. */
- class HuffmanCodec : public Codec {
-
- /** top level node of the Huffman tree used for decoding. */
- HuffmanNode * root;
-
- /** table of Huffman codes and bit lengths used for encoding. */
- HuffmanNode ** codeTable;
-
- /** intermediary destination of huffman codes. */
- BitWriter * writer;
-
- /** When true this HuffmanCodec reverses its bytes after encoding and before decoding to
- * provide compatibility with the backwards bit ordering of the original ST Huffman Encoding.
- * Default value is "false" (do not reverse bits). */
- bool reverseBits;
-
- /** When false this HuffmanCodec return -1 instead of expanding data during encoding.
- * Default value is "true" (allow data expansion). */
- bool expandable;
-
- /** Determines if this HuffmanCodec owns its Huffman tree nodes. */
- bool huffResourceOwner;
-
- /** Reverses the order of bits in a byte.
- * EG: The statement <code>reverseMap[0xAF] == 0xF5</code> is <code>true</code>. <br>
- * The index <code>10101111</code> stores the reverse value: <code>11110101</code>. <br>
- * Note: One array lookup is much faster than Eight bit manipulating loop iterations. */
- static unsigned char const reverseMap[];
-
- /** Number of bits the shortest huffman code in the tree has. */
- int shortestCode;
-
- public:
-
- /** Creates a new HuffmanCodec from the Huffman tree data.
- * @param treeData pointer to a buffer containing the Huffman tree structure definition.
- * @param dataLength length in bytes of the Huffman tree structure data. */
- HuffmanCodec( unsigned char const * const treeData, int dataLength );
-
- /** Creates a new HuffmanCodec that uses the specified Huffman resources.
- * @param treeRootNode The root node of a valid huffman tree.
- * @param leafCodeTable A code lookup table where references to HuffmanNodes are stored with their array index equal to their value.
- * Note: The tree nodes will not be released upon destruction of this HuffmanCodec. */
- HuffmanCodec(
- HuffmanNode * treeRootNode,
- HuffmanNode ** leafCodeTable
- );
-
- /** Frees resources used internally by this HuffmanCodec. */
- virtual ~HuffmanCodec();
-
- /** Decodes data read from an input buffer and stores the result in the output buffer.
- * @return number of bytes stored in the output buffer or -1 if an error occurs while encoding. */
- virtual int encode(
- unsigned char const * const input, /**< in: pointer to the first byte to encode. */
- unsigned char * const output, /**< out: pointer to an output buffer to store data. */
- int const &inLength, /**< in: number of bytes of input buffer to encoded. */
- int const &outLength /**< in: maximum length of data to output. */
- ) const;
-
- /** Decodes data read from an input buffer and stores the result in the output buffer.
- * @return number of bytes stored in the output buffer or -1 if an error occurs while decoding. */
- virtual int decode(
- unsigned char const * const input, /**< in: pointer to data that needs decoding. */
- unsigned char * const output, /**< out: pointer to output buffer to store decoded data. */
- int const &inLength, /**< in: number of bytes of input buffer to read. */
- int const &outLength /**< in: maximum length of data to output. */
- );
-
- /** Enables or Disables backwards bit ordering of bytes.
- * @param backwards "true" enables reversed bit order bytes, "false" uses standard byte bit ordering. */
- void reversedBytes( bool backwards );
-
- /** Check the state of backwards bit ordering for bytes.
- * @return true: bits within bytes are reversed. false: bits within bytes are normal. */
- bool reversedBytes();
-
- /** Enable or Disable data expansion during encoding.
- * @param expandingAllowed "true" allows encoding to expand data. "false" causes failure upon expansion. */
- void allowExpansion( bool expandable );
-
- /** Check the state of data expandability.
- * @return true: data expansion is allowed. false: data is not allowed to expand. */
- bool allowExpansion();
-
- /** Sets the ownership of this HuffmanCodec's resources.
- * @param ownsResources When false the tree will not be released upon destruction of this HuffmanCodec.
- * When true deleting this HuffmanCodec will cause the Huffman tree to be released. */
- void huffmanResourceOwner( bool ownsResources );
-
- /** Checks the ownership state of this HuffmanCodec's resources.
- * @return ownsResources When false the tree will not be released upon destruction of this HuffmanCodec.
- * When true deleting this HuffmanCodec will cause the Huffman tree to be released. */
- bool huffmanResourceOwner();
-
- /** Deletes all sub nodes of a HuffmanNode by traversing and deleting its child nodes.
- * @param treeNode pointer to a HuffmanNode whos children will be deleted. */
- static void deleteTree( HuffmanNode * treeNode );
-
- /** Recursively builds a Huffman Tree. <br>
- * The initial root node should have the following field values: <br>
- * <pre>
- * bitCount : 0
- * code : 0
- * value : -1
- * branch : 0 (NULL)
- * </pre>
- * @param node in/out: branch node of the Huffman Tree.
- * @param treeData in: char array containing the Huffman Tree's byte representation.
- * @param index in: Current array element to read the next tree node from.
- * @param dataLength in: Length of treeData
- * @param codeTable in/out: array of pointers to HuffmanNode structs.
- * @param tableLength in: maximum index allowed in the codeTable.
- * @return the next index to read from or -1 if an error occurs.
- * */
- int buildTree(
- HuffmanNode * node,
- unsigned char const * const treeData,
- int index,
- int dataLength,
- HuffmanNode ** const &codeTable,
- int tableLength
- );
-
- /** Decreases a codeLength to the shortest Huffman code bit length found in the node or any of its children. <br>
- * Set to Zero before calling to determine minimum code bit length.
- * @param node in: The node to begin searching at.
- * @param codeLength out: Variable to hold the longest code bit length found. */
- static void minCodeLength( HuffmanNode const * const node, int &codeLength );
-
- /** Increases a codeLength up to the longest Huffman code bit length found in the node or any of its children. <br>
- * Set to Zero before calling to determine maximum code bit length.
- * @param node in: The node to begin searching at.
- * @param codeLength out: Variable to hold the longest code bit length found. */
- static void maxCodeLength( HuffmanNode const * const node, int &codeLength );
-
- private:
-
- /** Perform initialization procedures common to all constructors. */
- void init();
-
- }; // end class Huffman Codec.
-} // end namespace skulltag
-
-#endif