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 **********************************************************************************/ 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
