mp3dec_layer3_int.c

这是在PCA下的基于IPP库示例代码例子,在网上下了IPP的库之后,设置相关参数就可以编译该代码.

  {
    17331497,    57555973,   108133460,   174813955,
   536870935,   412195909,   666376477,  1251956820,
  1039402258, -1134308520, -1631581894, -1046001545,
  -791820975, -1296121091,  -554439031,  -487758516,
  -437181022,  -396956545,  -364090208,  -338355488,
  -318280992,  -302629280,  -581104896,  -281462400,
  -272600668,  -250142024,  -213167061,  -163568839,
  -103612219,   -35888559,           0,           0,
           0,           0,           0,           0
  },

  {
           0,           0,           0,           0,
           0,           0,   161882836,   787012958,
   936585517, -1220582009, -1900017357, -1229622214,
  -892684672, -1402911360,  -581345472,  -499601056,
  -440953440,  -397334720,  -363743675,  -335460810,
  -310736462,  -288622674,  -536870920,  -249660198,
  -231892947,  -214801826,  -198099932,  -181525144,
  -164823238,  -147732101,  -129964873,  -222379216,
   -91002380,   -68888615,   -44164253,   -15881392
  }
};


static const Ipp32s _pIMDCTWinShort[]=
{
   280302863,   821806413,  1307305214,  1703713325,
  1984016189,  2129111628,  2129111628,  1984016189,
  1703713325,  1307305214,   821806413,   280302863
};

/*/////////////////////////////////////////////////////////////////////////////
//  Name:
//    _sIMDCT_36_32s
//
//  Description:
//    Performs 36 points IMDCT and windowing for long block.
//
//  Input Arguments:
//    pSrc      - pointer to the input buffer which is the
//                output of alias reduction.
//    blockType - indication of the window type:
//                  0: normal window;
//                  1: start block;
//                  2: short block;
//                  3: stop block.
//
//  Output Arguments:
//    pDst      - pointer to the output buffer of IMDCT for long block.
//
//  Returns:
//    ippStsNoErr     - no error.
//    ippStsBadArgErr - bad arguments.
//
//  Notes:
//    Input 18 data are in Q = IPP_MP3_REQUANT_Q.
//    output 36 data are in Q = IPP_MP3_HYBRID_Q.
//    about 460 cycle(evaluate).
*/

static void _sIMDCT_36_32s(Ipp32s* pSrc, Ipp32s* pDst, int blockType)
{
  int i;

  static const Ipp32s c9_50   =  2017974528;    /* Q30, max 1.9 */
  static const Ipp32s c9_51   =  1645067904;
  static const Ipp32s c9_52   =   372906624;
  static const Ipp32s c9_40   =  2114858496;
  static const Ipp32s c9_41   =  1380375936;
  static const Ipp32s c9_42   =   734482688;
  static const Ipp32s c9_43   =  1859775360;
  static const Ipp32s const_0 =   759250112;
  Ipp64s pSrc64[4];

  /* input aliasing for 36 point IDCT */
  /* stage 1 */
  {
    Ipp32s tmp0, tmp2;
    Ipp32s t0, t1, t2, t3;
    t0 = pSrc[0];
    t1 = pSrc[1];
    pDst[0] = t0;
    tmp0 = t0 + t1;
    pDst[1] = tmp0;

    for(i = 0; i <= 12; i += 4)
    {
      t2 = pSrc[2+i];
      t0 = pSrc[4+i];
      t3 = pSrc[3+i];
      pDst[2+i] = t1 + t2;
      t1 = pSrc[5+i];
      tmp2 = t2 + t3;
      pDst[3+i] = tmp0 + tmp2;
      pDst[4+i] = t3 + t0;
      tmp0 = t0 + t1;
      pDst[5+i] = tmp2 + tmp0;
    }
    /* about 60 cycle */
  }

  {
  /**************************************************************************
  //  Fast 9 Point Inverse Discrete Cosine Transform
  //  By  Francois-Raymond Boyer
  //    mailto:[e-mail]
  //    http://www.iro.umontreal.ca/~boyerf
  //  The code has been optimized for Intel processors
  //  (takes a lot of time to convert float to and from iternal
  //  FPU representation)
  //  It is a simple "factorization" of the IDCT matrix.
  //  ------------------------------------------------------------------------
  //  Then the code was optimized by Vadim Pisarevsky
  //  (two additions saved using <s> variable)
  //
  ***************************************************************************/
  {
    /* stage 2, right shift 2 bits */