1 /* 2 * Copyrightm (C) 2010 The Android Open Source Project 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 #ifndef __ECHO_SUPPRESSOR_H__ 18 #define __ECHO_SUPPRESSOR_H__ 19 20 #include <stdint.h> 21 22 class EchoSuppressor 23 { 24 public: 25 // The sampleCount must be power of 2. 26 EchoSuppressor(int sampleCount, int tailLength); 27 ~EchoSuppressor(); 28 void run(int16_t *playbacked, int16_t *recorded); 29 30 private: 31 int mShift; 32 int mScale; 33 int mSampleCount; 34 int mWindowSize; 35 int mTailLength; 36 int mRecordLength; 37 int mRecordOffset; 38 39 uint16_t *mXs; 40 uint32_t *mXSums; 41 uint32_t *mX2Sums; 42 uint16_t *mXRecords; 43 44 uint32_t mYSum; 45 uint32_t mY2Sum; 46 uint32_t *mYRecords; 47 uint32_t *mY2Records; 48 49 uint32_t *mXYSums; 50 uint32_t *mXYRecords; 51 52 int32_t mLastX; 53 int32_t mLastY; 54 55 float mWeight; 56 }; 57 58 #endif 59