66 lines
2.2 KiB
C
66 lines
2.2 KiB
C
|
/*
|
||
|
|
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
|
||
|
|
*
|
||
|
|
* Use of this source code is governed by a BSD-style license
|
||
|
|
* that can be found in the LICENSE file in the root of the source
|
||
|
|
* tree. An additional intellectual property rights grant can be found
|
||
|
|
* in the file PATENTS. All contributing project authors may
|
||
|
|
* be found in the AUTHORS file in the root of the source tree.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/******************************************************************
|
||
|
|
|
||
|
|
iLBC Speech Coder ANSI-C Source Code
|
||
|
|
|
||
|
|
WebRtcIlbcfix_Window32W32.c
|
||
|
|
|
||
|
|
******************************************************************/
|
||
|
|
|
||
|
|
#include "defines.h"
|
||
|
|
|
||
|
|
/*----------------------------------------------------------------*
|
||
|
|
* window multiplication
|
||
|
|
*---------------------------------------------------------------*/
|
||
|
|
|
||
|
|
void WebRtcIlbcfix_Window32W32(
|
||
|
|
WebRtc_Word32 *z, /* Output */
|
||
|
|
WebRtc_Word32 *x, /* Input (same domain as Output)*/
|
||
|
|
const WebRtc_Word32 *y, /* Q31 Window */
|
||
|
|
WebRtc_Word16 N /* length to process */
|
||
|
|
) {
|
||
|
|
WebRtc_Word16 i;
|
||
|
|
WebRtc_Word16 x_low, x_hi, y_low, y_hi;
|
||
|
|
WebRtc_Word16 left_shifts;
|
||
|
|
WebRtc_Word32 temp;
|
||
|
|
|
||
|
|
left_shifts = (WebRtc_Word16)WebRtcSpl_NormW32(x[0]);
|
||
|
|
WebRtcSpl_VectorBitShiftW32(x, N, x, (WebRtc_Word16)(-left_shifts));
|
||
|
|
|
||
|
|
|
||
|
|
/* The double precision numbers use a special representation:
|
||
|
|
* w32 = hi<<16 + lo<<1
|
||
|
|
*/
|
||
|
|
for (i = 0; i < N; i++) {
|
||
|
|
/* Extract higher bytes */
|
||
|
|
x_hi = (WebRtc_Word16) WEBRTC_SPL_RSHIFT_W32(x[i], 16);
|
||
|
|
y_hi = (WebRtc_Word16) WEBRTC_SPL_RSHIFT_W32(y[i], 16);
|
||
|
|
|
||
|
|
/* Extract lower bytes, defined as (w32 - hi<<16)>>1 */
|
||
|
|
temp = WEBRTC_SPL_LSHIFT_W32((WebRtc_Word32)x_hi, 16);
|
||
|
|
x_low = (WebRtc_Word16) WEBRTC_SPL_RSHIFT_W32((x[i] - temp), 1);
|
||
|
|
|
||
|
|
temp = WEBRTC_SPL_LSHIFT_W32((WebRtc_Word32)y_hi, 16);
|
||
|
|
y_low = (WebRtc_Word16) WEBRTC_SPL_RSHIFT_W32((y[i] - temp), 1);
|
||
|
|
|
||
|
|
/* Calculate z by a 32 bit multiplication using both low and high from x and y */
|
||
|
|
temp = WEBRTC_SPL_LSHIFT_W32(WEBRTC_SPL_MUL_16_16(x_hi, y_hi), 1);
|
||
|
|
temp = (temp + (WEBRTC_SPL_MUL_16_16_RSFT(x_hi, y_low, 14)));
|
||
|
|
|
||
|
|
z[i] = (temp + (WEBRTC_SPL_MUL_16_16_RSFT(x_low, y_hi, 14)));
|
||
|
|
}
|
||
|
|
|
||
|
|
WebRtcSpl_VectorBitShiftW32(z, N, z, left_shifts);
|
||
|
|
|
||
|
|
return;
|
||
|
|
}
|