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 **********************************************************************************/
SpreadingMax(const Word16 pbCnt,const Word16 * maskLowFactor,const Word16 * maskHighFactor,Word32 * pbSpreadedEnergy)35 void 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