huff_dec.cpp - Android社区 - https://www.androidos.net.cn/

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

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the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
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Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
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Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
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www.iis.fraunhofer.de/amm
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----------------------------------------------------------------------------------------------------------- */

/*!
  \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;
}

C++程序 | 121行 | 5.37 KB

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