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 AUDIO_SF_DECODER_H_
18 #define AUDIO_SF_DECODER_H_
19 
20 #include <media/stagefright/DataSource.h>
21 #include <media/stagefright/MediaSource.h>
22 #include <media/stagefright/FileSource.h>
23 #include <media/stagefright/MediaDefs.h>
24 #include <media/stagefright/MediaExtractor.h>
25 #include <media/stagefright/MetaData.h>
26 #include "NuCachedSource2.h"
27 #include "ThrottledSource.h"
28 
29 #include "android_GenericPlayer.h"
30 
31 //--------------------------------------------------------------------------------------------------
32 namespace android {
33 
34 // keep in sync with the entries of kPcmDecodeMetadataKeys[]
35 #define ANDROID_KEY_INDEX_PCMFORMAT_NUMCHANNELS   0
36 #define ANDROID_KEY_INDEX_PCMFORMAT_SAMPLERATE    1
37 #define ANDROID_KEY_INDEX_PCMFORMAT_BITSPERSAMPLE 2
38 #define ANDROID_KEY_INDEX_PCMFORMAT_CONTAINERSIZE 3
39 #define ANDROID_KEY_INDEX_PCMFORMAT_CHANNELMASK   4
40 #define ANDROID_KEY_INDEX_PCMFORMAT_ENDIANNESS    5
41 
42 // to keep in sync with the ANDROID_KEY_INDEX_PCMFORMAT_* constants in android_AudioSfDecoder.cpp
43 static const char* const kPcmDecodeMetadataKeys[] = {
44         ANDROID_KEY_PCMFORMAT_NUMCHANNELS, ANDROID_KEY_PCMFORMAT_SAMPLERATE,
45         ANDROID_KEY_PCMFORMAT_BITSPERSAMPLE, ANDROID_KEY_PCMFORMAT_CONTAINERSIZE,
46         ANDROID_KEY_PCMFORMAT_CHANNELMASK, ANDROID_KEY_PCMFORMAT_ENDIANNESS };
47 #define NB_PCMMETADATA_KEYS (sizeof(kPcmDecodeMetadataKeys)/sizeof(kPcmDecodeMetadataKeys[0]))
48 
49 // abstract base class for AudioToCbRenderer and it's subclasses
50 class AudioSfDecoder : public GenericPlayer
51 {
52 public:
53 
54     AudioSfDecoder(const AudioPlayback_Parameters* params);
55     virtual ~AudioSfDecoder();
56 
57     virtual void preDestroy();
58 
59     // overridden from GenericPlayer
60     virtual void play();
61     virtual void getPositionMsec(int* msec); //msec != NULL, ANDROID_UNKNOWN_TIME if unknown
62 
63     uint32_t getPcmFormatKeyCount() const;
64     bool     getPcmFormatKeySize(uint32_t index, uint32_t* pKeySize);
65     bool     getPcmFormatKeyName(uint32_t index, uint32_t keySize, char* keyName);
66     bool     getPcmFormatValueSize(uint32_t index, uint32_t* pValueSize);
67     bool     getPcmFormatKeyValue(uint32_t index, uint32_t size, uint32_t* pValue);
68 
69 protected:
70 
71     enum {
72         kWhatDecode       = 'deco',
73         kWhatRender       = 'rend',
74         kWhatCheckCache   = 'cach'
75     };
76 
77     // Async event handlers (called from the AudioSfDecoder's event loop)
78     void onDecode();
79     void onCheckCache(const sp<AMessage> &msg);
80     virtual void onRender() = 0;
81 
82     // Async event handlers (called from GenericPlayer's event loop)
83     virtual void onPrepare();
84     virtual void onPlay();
85     virtual void onPause();
86     virtual void onSeek(const sp<AMessage> &msg);
87     virtual void onLoop(const sp<AMessage> &msg);
88 
89     // overridden from GenericPlayer
90     virtual void onNotify(const sp<AMessage> &msg);
91     virtual void onMessageReceived(const sp<AMessage> &msg);
92 
93     // to be implemented by subclasses of AudioSfDecoder to do something with the audio samples
94     // (called from GenericPlayer's event loop)
95     virtual void createAudioSink() = 0;
96     virtual void updateAudioSink() = 0; // called with mBufferSourceLock held
97     virtual void startAudioSink() = 0;
98     virtual void pauseAudioSink() = 0;
99 
100     sp<DataSource>  mDataSource; // where the raw data comes from
101     sp<IMediaSource> mAudioSource;// the decoder reading from the data source
102     // used to indicate mAudioSource was successfully started, but wasn't stopped
103     bool            mAudioSourceStarted;
104 
105     // negative values indicate invalid value
106     int64_t mBitrate;  // in bits/sec
107     int64_t mDurationUsec; // ANDROID_UNKNOWN_TIME if unknown
108 
109     // buffer passed from decoder to renderer
110     MediaBuffer *mDecodeBuffer;
111 
112     // mutex used to protect the decode buffer, the audio source and its running state
113     Mutex       mBufferSourceLock;
114 
115     void notifyPrepared(status_t prepareRes);
116 
117     int64_t mSeekTimeMsec;
118     int64_t mLastDecodedPositionUs; // ANDROID_UNKNOWN_TIME if unknown
119     // mutex used for seek flag, seek time (mSeekTimeMsec),
120     //   and last decoded position (mLastDecodedPositionUs)
121     Mutex mTimeLock;
122 
123     // informations that can be retrieved in the PCM format queries
124     //  these values are only written in the event loop
125     uint32_t mPcmFormatValues[NB_PCMMETADATA_KEYS];
126     // protects mPcmFormatValues
127     Mutex    mPcmFormatLock;
128 
advancesPositionInRealTime()129     virtual bool advancesPositionInRealTime() const { return false; }
130 
131 private:
132     bool wantPrefetch();
133     CacheStatus_t getCacheRemaining(bool *eos);
134     int64_t getPositionUsec(); // ANDROID_UNKNOWN_TIME if unknown
135 
136     // convenience function to update internal state when decoding parameters have changed,
137     // called with a lock on mBufferSourceLock
138     void hasNewDecodeParams();
139 
140     static bool isSupportedCodec(const char* mime);
141 
142 private:
143     DISALLOW_EVIL_CONSTRUCTORS(AudioSfDecoder);
144 
145 };
146 
147 } // namespace android
148 
149 #endif // AUDIO_SF_DECODER_H_
150