/* | |
** Copyright 2003-2010, VisualOn, Inc. | |
** | |
** Licensed under the Apache License, Version 2.0 (the "License"); | |
** you may not use this file except in compliance with the License. | |
** You may obtain a copy of the License at | |
** | |
** http://www.apache.org/licenses/LICENSE-2.0 | |
** | |
** Unless required by applicable law or agreed to in writing, software | |
** distributed under the License is distributed on an "AS IS" BASIS, | |
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
** See the License for the specific language governing permissions and | |
** limitations under the License. | |
*/ | |
/*********************************************************************** | |
File: convolve.c | |
Description:Perform the convolution between two vectors x[] and h[] | |
and write the result in the vector y[] | |
************************************************************************/ | |
#include "typedef.h" | |
#include "basic_op.h" | |
void Convolve ( | |
Word16 x[], /* (i) : input vector */ | |
Word16 h[], /* (i) : impulse response */ | |
Word16 y[], /* (o) : output vector */ | |
Word16 L /* (i) : vector size */ | |
) | |
{ | |
Word32 i, n; | |
Word16 *tmpH,*tmpX; | |
Word32 s; | |
for (n = 0; n < 64;) | |
{ | |
tmpH = h+n; | |
tmpX = x; | |
i=n+1; | |
s = vo_mult32((*tmpX++), (*tmpH--));i--; | |
while(i>0) | |
{ | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
i -= 4; | |
} | |
y[n] = ((s<<1) + 0x8000)>>16; | |
n++; | |
tmpH = h+n; | |
tmpX = x; | |
i=n+1; | |
s = vo_mult32((*tmpX++), (*tmpH--));i--; | |
s += vo_mult32((*tmpX++), (*tmpH--));i--; | |
while(i>0) | |
{ | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
i -= 4; | |
} | |
y[n] = ((s<<1) + 0x8000)>>16; | |
n++; | |
tmpH = h+n; | |
tmpX = x; | |
i=n+1; | |
s = vo_mult32((*tmpX++), (*tmpH--));i--; | |
s += vo_mult32((*tmpX++), (*tmpH--));i--; | |
s += vo_mult32((*tmpX++), (*tmpH--));i--; | |
while(i>0) | |
{ | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
i -= 4; | |
} | |
y[n] = ((s<<1) + 0x8000)>>16; | |
n++; | |
s = 0; | |
tmpH = h+n; | |
tmpX = x; | |
i=n+1; | |
while(i>0) | |
{ | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
s += vo_mult32((*tmpX++), (*tmpH--)); | |
i -= 4; | |
} | |
y[n] = ((s<<1) + 0x8000)>>16; | |
n++; | |
} | |
return; | |
} | |