1/*
2 ** Copyright 2003-2010, VisualOn, Inc.
3 **
4 ** Licensed under the Apache License, Version 2.0 (the "License");
5 ** you may not use this file except in compliance with the License.
6 ** You may obtain a copy of the License at
7 **
8 **     http://www.apache.org/licenses/LICENSE-2.0
9 **
10 ** Unless required by applicable law or agreed to in writing, software
11 ** distributed under the License is distributed on an "AS IS" BASIS,
12 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 ** See the License for the specific language governing permissions and
14 ** limitations under the License.
15 */
16/*******************************************************************************
17	File:		spreading.c
18
19	Content:	Spreading of energy function
20
21*******************************************************************************/
22
23#include "basic_op.h"
24#include "oper_32b.h"
25#include "spreading.h"
26
27/*********************************************************************************
28*
29* function name: SpreadingMax
30* description:  spreading the energy
31*				 higher frequencies thr(n) = max(thr(n), sh(n)*thr(n-1))
32*				 lower frequencies  thr(n) = max(thr(n), sl(n)*thr(n+1))
33*
34**********************************************************************************/
35void SpreadingMax(const Word16 pbCnt,
36                  const Word16 *maskLowFactor,
37                  const Word16 *maskHighFactor,
38                  Word32       *pbSpreadedEnergy)
39{
40  Word32 i;
41
42  /* slope to higher frequencies */
43  for (i=1; i<pbCnt; i++) {
44    pbSpreadedEnergy[i] = max(pbSpreadedEnergy[i],
45                                L_mpy_ls(pbSpreadedEnergy[i-1], maskHighFactor[i]));
46  }
47  /* slope to lower frequencies */
48  for (i=pbCnt - 2; i>=0; i--) {
49    pbSpreadedEnergy[i] = max(pbSpreadedEnergy[i],
50                                L_mpy_ls(pbSpreadedEnergy[i+1], maskLowFactor[i]));
51  }
52}
53