1/*
2 * Copyright (C) 2009 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 AUDIO_SOURCE_H_
18
19#define AUDIO_SOURCE_H_
20
21#include <media/AudioRecord.h>
22#include <media/AudioSystem.h>
23#include <media/stagefright/MediaSource.h>
24#include <media/stagefright/MediaBuffer.h>
25#include <utils/List.h>
26
27#include <system/audio.h>
28
29namespace android {
30
31class AudioRecord;
32
33struct AudioSource : public MediaSource, public MediaBufferObserver {
34    // Note that the "channels" parameter _is_ the number of channels,
35    // _not_ a bitmask of audio_channels_t constants.
36    AudioSource(
37            audio_source_t inputSource,
38            uint32_t sampleRate,
39            uint32_t channels = 1);
40
41    status_t initCheck() const;
42
43    virtual status_t start(MetaData *params = NULL);
44    virtual status_t stop() { return reset(); }
45    virtual sp<MetaData> getFormat();
46
47    // Returns the maximum amplitude since last call.
48    int16_t getMaxAmplitude();
49
50    virtual status_t read(
51            MediaBuffer **buffer, const ReadOptions *options = NULL);
52
53    status_t dataCallback(const AudioRecord::Buffer& buffer);
54    virtual void signalBufferReturned(MediaBuffer *buffer);
55
56protected:
57    virtual ~AudioSource();
58
59private:
60    enum {
61        kMaxBufferSize = 2048,
62
63        // After the initial mute, we raise the volume linearly
64        // over kAutoRampDurationUs.
65        kAutoRampDurationUs = 300000,
66
67        // This is the initial mute duration to suppress
68        // the video recording signal tone
69        kAutoRampStartUs = 0,
70    };
71
72    Mutex mLock;
73    Condition mFrameAvailableCondition;
74    Condition mFrameEncodingCompletionCondition;
75
76    AudioRecord *mRecord;
77    status_t mInitCheck;
78    bool mStarted;
79    int32_t mSampleRate;
80
81    bool mTrackMaxAmplitude;
82    int64_t mStartTimeUs;
83    int16_t mMaxAmplitude;
84    int64_t mPrevSampleTimeUs;
85    int64_t mInitialReadTimeUs;
86    int64_t mNumFramesReceived;
87    int64_t mNumClientOwnedBuffers;
88
89    List<MediaBuffer * > mBuffersReceived;
90
91    void trackMaxAmplitude(int16_t *data, int nSamples);
92
93    // This is used to raise the volume from mute to the
94    // actual level linearly.
95    void rampVolume(
96        int32_t startFrame, int32_t rampDurationFrames,
97        uint8_t *data,   size_t bytes);
98
99    void queueInputBuffer_l(MediaBuffer *buffer, int64_t timeUs);
100    void releaseQueuedFrames_l();
101    void waitOutstandingEncodingFrames_l();
102    status_t reset();
103
104    AudioSource(const AudioSource &);
105    AudioSource &operator=(const AudioSource &);
106};
107
108}  // namespace android
109
110#endif  // AUDIO_SOURCE_H_
111