aac_dec_ltp_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.

/*
//
//                  INTEL CORPORATION PROPRIETARY INFORMATION
//     This software is supplied under the terms of a license agreement or
//     nondisclosure agreement with Intel Corporation and may not be copied
//     or disclosed except in accordance with the terms of that agreement.
//          Copyright(c) 2003-2005 Intel Corporation. All Rights Reserved.
//
//     Intel(R) Integrated Performance Primitives AAC Decode Sample for Windows*
//
//  By downloading and installing this sample, you hereby agree that the
//  accompanying Materials are being provided to you under the terms and
//  conditions of the End User License Agreement for the Intel(R) Integrated
//  Performance Primitives product previously accepted by you. Please refer
//  to the file ipplic.htm located in the root directory of your Intel(R) IPP
//  product installation for more information.
//
//  MPEG-4 and AAC are international standards promoted by ISO, IEC, ITU, ETSI
//  and other organizations. Implementations of these standards, or the standard
//  enabled platforms may require licenses from various entities, including
//  Intel Corporation.
//
*/

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

#include "aac_dec_ltp_int.h"

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

static int g_ltp_coef[] = {
  0x2488765c, 0x2c955b46, 0x340841ee, 0x3a52ce03,
  0x3f089a02, 0x44586013, 0x4c7457c1, 0x57a66dbd
};

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

static void mulScale(Ipp16s* pSrc,
                     Ipp32s  val,
                     Ipp32s* pDst,
                     int     len)
{
  int i;

  for (i = 0; i < len; i++) {
    pDst[i] = (Ipp32s)((val * (Ipp64s)pSrc[i] + 32768) >> 16);
  }
}
/********************************************************************/

void ics_apply_ltp_I(sLtp *p_data,
                     s_SE_Individual_channel_stream *p_stream,
                     Ipp32s *p_spectrum)
{
  int     i, j;
  Ipp32s  filterbank_in[2048], *pTmp;
  Ipp32s  filterbank_out[1024];
  Ipp32s  real_coef;
  int     lag_size;
  int     lag;
  int     num;
  int     start;
  int     in_counter;
  int     sfb;

  if (0 == p_stream->ltp_data_present)
    return;

  real_coef = g_ltp_coef[p_stream->ltp_coef];
  lag = p_stream->ltp_lag;

  if (EIGHT_SHORT_SEQUENCE == p_stream->window_sequence) {
    int     max_sfb = p_stream->max_sfb;

    if (MAX_LTP_SFB_SHORT < max_sfb)
      max_sfb = MAX_LTP_SFB_SHORT;

    for (i = 0; i < 8; i++) {
      if (p_stream->ltp_short_used[i]) {
        int     delay = lag + p_stream->ltp_short_lag[i] - 8;

        start = 3 * 1024 - 2 * 128 - delay;
        lag_size = 2 * 128;

        pTmp = filterbank_in;

        if (start < 1024) {
          num = 1024 - start;
          if (num > lag_size)
            num = lag_size;

          mulScale(p_data->p_samples_1st_part + start, real_coef, pTmp, num);

          lag_size -= num;
          start = 1024;
          pTmp += num;
        }

        if ((start < 2 * 1024) && (lag_size > 0)) {
          num = 2 * 1024 - start;
          if (num > lag_size)
            num = lag_size;

          mulScale(p_data->p_samples_2nd_part + start - 1024, real_coef, pTmp, num);

          lag_size -= num;
          start = 2 * 1024;
          pTmp += num;
        }

        if (lag_size > 0) {
          num = 3 * 1024 - start;
          if (num > lag_size)
            num = lag_size;

          mulScale(p_data->p_samples_3rd_part + start - 2 * 1024, real_coef, pTmp, num);

          lag_size -= num;
        }

        if (lag_size > 0) {
          ippsZero_32s(pTmp, lag_size);
        }

        FilterbankEncInt(p_data->p_filterbank_data, filterbank_in,
                         &filterbank_in[1024], p_stream->window_sequence,
                         p_stream->window_shape, p_data->prev_windows_shape,
                         filterbank_out);

        if (0 != p_stream->tns_data_present) {
          ics_apply_tns_enc_I(p_data->p_tns_data, filterbank_out);
        }

        for (sfb = 0; sfb < max_sfb; sfb++) {
          int     begin = p_stream->sfb_offset_short_window[sfb];
          int     end = p_stream->sfb_offset_short_window[sfb + 1];

          for (j = begin; j < end; j++) {
            p_spectrum[i * 128 + j] += filterbank_out[j];
          }
        }
      }
    }
  } else {
    int     delay = lag;

    lag_size = 2048;
    in_counter = 0;
    start = 2048 - delay;
    pTmp = filterbank_in;

    if (start < 1024) {
      num = 1024 - start;

      mulScale(p_data->p_samples_1st_part + start, real_coef, pTmp, num);

      lag_size -= num;
      start = 1024;
      pTmp += num;
    }

    num = 2 * 1024 - start;

    mulScale(p_data->p_samples_2nd_part + start - 1024, real_coef, pTmp, num);

    lag_size -= num;
    pTmp += num;

    if (lag_size > 0) {
      num = lag_size > 1024 ? 1024 : lag_size;

      mulScale(p_data->p_samples_3rd_part, real_coef, pTmp, num);

      lag_size -= num;
      pTmp += num;
    }

    if (lag_size > 0) {
      ippsZero_32s(pTmp, lag_size);
    }

    FilterbankEncInt(p_data->p_filterbank_data, filterbank_in,
                     &filterbank_in[1024], p_stream->window_sequence,
                     p_stream->window_shape, p_data->prev_windows_shape,
                     filterbank_out);

    if (0 != p_stream->tns_data_present) {
      ics_apply_tns_enc_I(p_data->p_tns_data, filterbank_out);
    }

    for (sfb = 0; sfb < p_stream->max_sfb; sfb++) {
      if (p_stream->ltp_long_used[sfb]) {
        int     begin = p_stream->sfb_offset_long_window[sfb];
        int     end = p_stream->sfb_offset_long_window[sfb + 1];

        for (i = begin; i < end; i++) {
          p_spectrum[i] += filterbank_out[i];
        }
      }
    }
  }
}

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