AudioMixer.h revision 17a736c3e1d062d7fc916329eb32aef8935614af 
1/*
2**
3** Copyright 2007, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18#ifndef ANDROID_AUDIO_MIXER_H
19#define ANDROID_AUDIO_MIXER_H
20
21#include <stdint.h>
22#include <sys/types.h>
23
24#include "AudioBufferProvider.h"
25#include "AudioResampler.h"
26
27namespace android {
28
29// ----------------------------------------------------------------------------
30
31class AudioMixer
32{
33public:
34                            AudioMixer(size_t frameCount, uint32_t sampleRate);
35
36    /*virtual*/             ~AudioMixer();  // non-virtual saves a v-table, restore if sub-classed
37
38    static const uint32_t MAX_NUM_TRACKS = 32;
39    static const uint32_t MAX_NUM_CHANNELS = 2;
40
41    static const uint16_t UNITY_GAIN = 0x1000;
42
43    enum { // names
44
45        // track names (MAX_NUM_TRACKS units)
46        TRACK0          = 0x1000,
47
48        // 0x2000 is unused
49
50        // setParameter targets
51        TRACK           = 0x3000,
52        RESAMPLE        = 0x3001,
53        RAMP_VOLUME     = 0x3002, // ramp to new volume
54        VOLUME          = 0x3003, // don't ramp
55
56        // set Parameter names
57        // for target TRACK
58        CHANNEL_MASK    = 0x4000,
59        FORMAT          = 0x4001,
60        MAIN_BUFFER     = 0x4002,
61        AUX_BUFFER      = 0x4003,
62        // for target RESAMPLE
63        SAMPLE_RATE     = 0x4100,
64        RESET           = 0x4101,
65        // for target RAMP_VOLUME and VOLUME (8 channels max)
66        VOLUME0         = 0x4200,
67        VOLUME1         = 0x4201,
68        AUXLEVEL        = 0x4210,
69    };
70
71
72    // For all APIs with "name": TRACK0 <= name < TRACK0 + MAX_NUM_TRACKS
73
74    // Allocate a track name.  Returns new track name if successful, -1 on failure.
75    int         getTrackName();
76
77    // Free an allocated track by name
78    void        deleteTrackName(int name);
79
80    // Enable or disable an allocated track by name
81    void        enable(int name);
82    void        disable(int name);
83
84    void        setParameter(int name, int target, int param, void *value);
85
86    void        setBufferProvider(int name, AudioBufferProvider* bufferProvider);
87    void        process(int64_t pts);
88
89    uint32_t    trackNames() const { return mTrackNames; }
90
91    size_t      getUnreleasedFrames(int name) const;
92
93private:
94
95    enum {
96        NEEDS_CHANNEL_COUNT__MASK   = 0x00000003,
97        NEEDS_FORMAT__MASK          = 0x000000F0,
98        NEEDS_MUTE__MASK            = 0x00000100,
99        NEEDS_RESAMPLE__MASK        = 0x00001000,
100        NEEDS_AUX__MASK             = 0x00010000,
101    };
102
103    enum {
104        NEEDS_CHANNEL_1             = 0x00000000,
105        NEEDS_CHANNEL_2             = 0x00000001,
106
107        NEEDS_FORMAT_16             = 0x00000010,
108
109        NEEDS_MUTE_DISABLED         = 0x00000000,
110        NEEDS_MUTE_ENABLED          = 0x00000100,
111
112        NEEDS_RESAMPLE_DISABLED     = 0x00000000,
113        NEEDS_RESAMPLE_ENABLED      = 0x00001000,
114
115        NEEDS_AUX_DISABLED     = 0x00000000,
116        NEEDS_AUX_ENABLED      = 0x00010000,
117    };
118
119    struct state_t;
120    struct track_t;
121
122    typedef void (*hook_t)(track_t* t, int32_t* output, size_t numOutFrames, int32_t* temp, int32_t* aux);
123    static const int BLOCKSIZE = 16; // 4 cache lines
124
125    struct track_t {
126        uint32_t    needs;
127
128        union {
129        int16_t     volume[MAX_NUM_CHANNELS]; // [0]3.12 fixed point
130        int32_t     volumeRL;
131        };
132
133        int32_t     prevVolume[MAX_NUM_CHANNELS];
134
135        // 16-byte boundary
136
137        int32_t     volumeInc[MAX_NUM_CHANNELS];
138        int32_t     auxInc;
139        int32_t     prevAuxLevel;
140
141        // 16-byte boundary
142
143        int16_t     auxLevel;       // 0 <= auxLevel <= MAX_GAIN_INT, but signed for mul performance
144        uint16_t    frameCount;
145
146        uint8_t     channelCount;   // 1 or 2, redundant with (needs & NEEDS_CHANNEL_COUNT__MASK)
147        uint8_t     format;         // always 16
148        uint16_t    enabled;        // actually bool
149        uint32_t    channelMask;    // currently under-used
150
151        AudioBufferProvider*                bufferProvider;
152
153        // 16-byte boundary
154
155        mutable AudioBufferProvider::Buffer buffer; // 8 bytes
156
157        hook_t      hook;
158        const void* in;             // current location in buffer
159
160        // 16-byte boundary
161
162        AudioResampler*     resampler;
163        uint32_t            sampleRate;
164        int32_t*           mainBuffer;
165        int32_t*           auxBuffer;
166
167        // 16-byte boundary
168
169        uint64_t    localTimeFreq;
170
171        int64_t     padding;
172
173        // 16-byte boundary
174
175        bool        setResampler(uint32_t sampleRate, uint32_t devSampleRate);
176        bool        doesResample() const { return resampler != NULL; }
177        void        resetResampler() { if (resampler != NULL) resampler->reset(); }
178        void        adjustVolumeRamp(bool aux);
179        size_t      getUnreleasedFrames() const { return resampler != NULL ?
180                                                    resampler->getUnreleasedFrames() : 0; };
181    };
182
183    // pad to 32-bytes to fill cache line
184    struct state_t {
185        uint32_t        enabledTracks;
186        uint32_t        needsChanged;
187        size_t          frameCount;
188        void            (*hook)(state_t* state, int64_t pts);   // one of process__*, never NULL
189        int32_t         *outputTemp;
190        int32_t         *resampleTemp;
191        int32_t         reserved[2];
192        track_t         tracks[MAX_NUM_TRACKS]; __attribute__((aligned(32)));
193    };
194
195    // bitmask of allocated track names, where bit 0 corresponds to TRACK0 etc.
196    uint32_t        mTrackNames;
197    const uint32_t  mSampleRate;
198
199    state_t         mState __attribute__((aligned(32)));
200
201    void invalidateState(uint32_t mask);
202
203    static void track__genericResample(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
204    static void track__nop(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
205    static void track__16BitsStereo(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
206    static void track__16BitsMono(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
207    static void volumeRampStereo(track_t* t, int32_t* out, size_t frameCount, int32_t* temp, int32_t* aux);
208    static void volumeStereo(track_t* t, int32_t* out, size_t frameCount, int32_t* temp, int32_t* aux);
209
210    static void process__validate(state_t* state, int64_t pts);
211    static void process__nop(state_t* state, int64_t pts);
212    static void process__genericNoResampling(state_t* state, int64_t pts);
213    static void process__genericResampling(state_t* state, int64_t pts);
214    static void process__OneTrack16BitsStereoNoResampling(state_t* state,
215                                                          int64_t pts);
216#if 0
217    static void process__TwoTracks16BitsStereoNoResampling(state_t* state,
218                                                           int64_t pts);
219#endif
220
221    static int64_t calculateOutputPTS(const track_t& t, int64_t basePTS,
222                                      int outputFrameIndex);
223};
224
225// ----------------------------------------------------------------------------
226}; // namespace android
227
228#endif // ANDROID_AUDIO_MIXER_H
229