Files
platform-external-webrtc/webrtc/modules/audio_coding/codecs/ilbc/window32_w32.c
bjornv@webrtc.org 4ab23d0e8f Refactor audio_coding/ilbc: removes usage of macro WEBRTC_SPL_LSHIFT_W32
The macro is defined as
#define WEBRTC_SPL_LSHIFT_W32(a, b) ((a) << (b))
It is a trivial operation that need no macro. In fact it may be confusing for to the user, since it can be interpreted as having an implicit cast to int32_t.

Also removes unnecessary casts to int32_t from int16_t.

BUG=3348,3353
TESTED=locally on linux and trybots
R=kwiberg@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/48519004

Cr-Commit-Position: refs/heads/master@{#8800}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8800 4adac7df-926f-26a2-2b94-8c16560cd09d
2015-03-20 06:01:43 +00:00

63 lines
1.8 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(
int32_t *z, /* Output */
int32_t *x, /* Input (same domain as Output)*/
const int32_t *y, /* Q31 Window */
int16_t N /* length to process */
) {
int16_t i;
int16_t x_low, x_hi, y_low, y_hi;
int16_t left_shifts;
int32_t temp;
left_shifts = (int16_t)WebRtcSpl_NormW32(x[0]);
WebRtcSpl_VectorBitShiftW32(x, N, x, (int16_t)(-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 = (int16_t)(x[i] >> 16);
y_hi = (int16_t)(y[i] >> 16);
/* Extract lower bytes, defined as (w32 - hi<<16)>>1 */
x_low = (int16_t)((x[i] - (x_hi << 16)) >> 1);
y_low = (int16_t)((y[i] - (y_hi << 16)) >> 1);
/* Calculate z by a 32 bit multiplication using both low and high from x and y */
temp = ((x_hi * y_hi) << 1) + ((x_hi * y_low) >> 14);
z[i] = temp + ((x_low * y_hi) >> 14);
}
WebRtcSpl_VectorBitShiftW32(z, N, z, left_shifts);
return;
}