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.
29class 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