libSBRdec/src/huff_dec.cpp

/* -----------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android

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----------------------------------------------------------------------------- */

/**************************** SBR decoder library ******************************

   Author(s):

   Description:

*******************************************************************************/

/*!
  \file
  \brief  Huffman Decoder
*/

#include "huff_dec.h"

/***************************************************************************/
/*!
  \brief     Decodes one huffman code word

  Reads bits from the bitstream until a valid codeword is found.
  The table entries are interpreted either as index to the next entry
  or - if negative - as the codeword.

  \return    decoded value

  \author

****************************************************************************/
int DecodeHuffmanCW(Huffman h, /*!< pointer to huffman codebook table */
                    HANDLE_FDK_BITSTREAM hBs) /*!< Handle to Bitbuffer */
{
  SCHAR index = 0;
  int value, bit;

  while (index >= 0) {
    bit = FDKreadBits(hBs, 1);
    index = h[index][bit];
  }

  value = index + 64; /* Add offset */

  return value;
}