1 /* 2 * Copyright (C) 2011 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 FRAMEWORKS_EX_VARIABLESPEED_JNI_DECODE_BUFFER_H_ 18 #define FRAMEWORKS_EX_VARIABLESPEED_JNI_DECODE_BUFFER_H_ 19 20 #include <integral_types.h> 21 #include <macros.h> 22 #include <stdlib.h> 23 #include <vector> 24 25 // DecodeBuffer is used to store arrays of int16 values for audio. 26 // 27 // This class is not thread-safe. You should provide your own 28 // synchronization if you wish to use it from multiple threads. 29 class DecodeBuffer { 30 public: 31 DecodeBuffer(size_t sizeOfOneBuffer, size_t maxSize); 32 virtual ~DecodeBuffer(); 33 size_t GetSizeInBytes() const; 34 void AddData(int8_t* pointer, size_t lengthInBytes); 35 void Clear(); 36 void AdvanceHeadPointerShorts(size_t numberOfShorts); 37 int16 GetAtIndex(size_t index); 38 bool IsTooLarge() const; 39 size_t GetTotalAdvancedCount() const; 40 41 private: 42 void PushValue(int16 value); 43 44 size_t sizeOfOneBuffer_; 45 size_t maxSize_; 46 size_t start_; 47 size_t end_; 48 size_t advancedCount_; 49 // This vector isn't ideal because we perform a number of queue-like 50 // operations: namely removing from the front and appending at the back. 51 // However we also need constant-time access to the elements of this 52 // vector, and therefore it's not good enough to use a std::queue. 53 // In practice this data structure choice doesn't seem to be a bottleneck. 54 std::vector<int16*> data_; 55 56 DISALLOW_COPY_AND_ASSIGN(DecodeBuffer); 57 }; 58 59 #endif // FRAMEWORKS_EX_VARIABLESPEED_JNI_DECODE_BUFFER_H_ 60
