1 /* 2 * Copyright (C) 2004-2010 NXP Software 3 * Copyright (C) 2010 The Android Open Source Project 4 * 5 * Licensed under the Apache License, Version 2.0 (the "License"); 6 * you may not use this file except in compliance with the License. 7 * You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 /********************************************************************************** 19 INCLUDE FILES 20 ***********************************************************************************/ 21 22 #include "VectorArithmetic.h" 23 24 /********************************************************************************** 25 FUNCTION DelayMix_16x16 26 ***********************************************************************************/ 27 28 void DelayMix_16x16(const LVM_INT16 *src, /* Source 1, to be delayed */ 29 LVM_INT16 *delay, /* Delay buffer */ 30 LVM_INT16 size, /* Delay size */ 31 LVM_INT16 *dst, /* Source/destination */ 32 LVM_INT16 *pOffset, /* Delay offset */ 33 LVM_INT16 n) /* Number of stereo samples */ 34 { 35 LVM_INT16 i; 36 LVM_INT16 Offset = *pOffset; 37 LVM_INT16 temp; 38 39 for (i=0; i<n; i++) 40 { 41 /* Left channel */ 42 temp = (LVM_INT16)((LVM_UINT32)((LVM_INT32)(*dst) + (LVM_INT32)delay[Offset]) >> 1); 43 *dst = temp; 44 dst++; 45 46 delay[Offset] = *src; 47 Offset++; 48 src++; 49 50 51 /* Right channel */ 52 temp = (LVM_INT16)((LVM_UINT32)((LVM_INT32)(*dst) - (LVM_INT32)delay[Offset]) >> 1); 53 *dst = temp; 54 dst++; 55 56 delay[Offset] = *src; 57 Offset++; 58 src++; 59 60 /* Make the reverb delay buffer a circular buffer */ 61 if (Offset >= size) 62 { 63 Offset = 0; 64 } 65 } 66 67 /* Update the offset */ 68 *pOffset = Offset; 69 70 return; 71 } 72 73 /**********************************************************************************/ 74
