AudioMixer.h revision 1c48c3c61970527b97892ab6a2daae8eaac26964 
1/* //device/include/server/AudioFlinger/AudioMixer.h
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
31#define LIKELY( exp )       (__builtin_expect( (exp) != 0, true  ))
32#define UNLIKELY( exp )     (__builtin_expect( (exp) != 0, false ))
33
34// ----------------------------------------------------------------------------
35
36class AudioMixer
37{
38public:
39                            AudioMixer(size_t frameCount, uint32_t sampleRate);
40
41                            ~AudioMixer();
42
43    static const uint32_t MAX_NUM_TRACKS = 32;
44    static const uint32_t MAX_NUM_CHANNELS = 2;
45
46    static const uint16_t UNITY_GAIN = 0x1000;
47
48    enum { // names
49
50        // track units (32 units)
51        TRACK0          = 0x1000,
52
53        // 0x2000 is unused
54
55        // setParameter targets
56        TRACK           = 0x3000,
57        RESAMPLE        = 0x3001,
58        RAMP_VOLUME     = 0x3002, // ramp to new volume
59        VOLUME          = 0x3003, // don't ramp
60
61        // set Parameter names
62        // for target TRACK
63        CHANNEL_MASK    = 0x4000,
64        FORMAT          = 0x4001,
65        MAIN_BUFFER     = 0x4002,
66        AUX_BUFFER      = 0x4003,
67        // for TARGET RESAMPLE
68        SAMPLE_RATE     = 0x4100,
69        RESET           = 0x4101,
70        // for TARGET VOLUME (8 channels max)
71        VOLUME0         = 0x4200,
72        VOLUME1         = 0x4201,
73        AUXLEVEL        = 0x4210,
74    };
75
76
77    int         getTrackName();
78    void        deleteTrackName(int name);
79
80    void        enable();
81    void        disable();
82
83    status_t    setActiveTrack(int track);
84    status_t    setParameter(int target, int name, void *value);
85
86    status_t    setBufferProvider(AudioBufferProvider* bufferProvider);
87    void        process();
88
89    uint32_t    trackNames() const { return mTrackNames; }
90
91    static void ditherAndClamp(int32_t* out, int32_t const *sums, size_t c);
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    static inline int32_t applyVolume(int32_t in, int32_t v) {
120        return in * v;
121    }
122
123
124    struct state_t;
125    struct track_t;
126
127    typedef void (*mix_t)(state_t* state);
128    typedef void (*hook_t)(track_t* t, int32_t* output, size_t numOutFrames, int32_t* temp, int32_t* aux);
129    static const int BLOCKSIZE = 16; // 4 cache lines
130
131    struct track_t {
132        uint32_t    needs;
133
134        union {
135        int16_t     volume[2];      // [0]3.12 fixed point
136        int32_t     volumeRL;
137        };
138
139        int32_t     prevVolume[2];
140
141        int32_t     volumeInc[2];
142        int32_t     auxLevel;
143        int32_t     auxInc;
144        int32_t     prevAuxLevel;
145
146        uint16_t    frameCount;
147
148        uint8_t     channelCount : 4;
149        uint8_t     enabled      : 1;
150        uint8_t     reserved0    : 3;
151        uint8_t     format;
152        uint32_t    channelMask;
153
154        AudioBufferProvider*                bufferProvider;
155        mutable AudioBufferProvider::Buffer buffer;
156
157        hook_t      hook;
158        void const* in;             // current location in buffer
159
160        AudioResampler*     resampler;
161        uint32_t            sampleRate;
162        int32_t*           mainBuffer;
163        int32_t*           auxBuffer;
164
165        bool        setResampler(uint32_t sampleRate, uint32_t devSampleRate);
166        bool        doesResample() const;
167        void        resetResampler();
168        void        adjustVolumeRamp(bool aux);
169    };
170
171    // pad to 32-bytes to fill cache line
172    struct state_t {
173        uint32_t        enabledTracks;
174        uint32_t        needsChanged;
175        size_t          frameCount;
176        mix_t           hook;
177        int32_t         *outputTemp;
178        int32_t         *resampleTemp;
179        int32_t         reserved[2];
180        track_t         tracks[32]; __attribute__((aligned(32)));
181    };
182
183    int             mActiveTrack;
184    uint32_t        mTrackNames;
185    const uint32_t  mSampleRate;
186
187    state_t         mState __attribute__((aligned(32)));
188
189    void invalidateState(uint32_t mask);
190
191    static void track__genericResample(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
192    static void track__nop(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
193    static void track__16BitsStereo(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
194    static void track__16BitsMono(track_t* t, int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
195    static void volumeRampStereo(track_t* t, int32_t* out, size_t frameCount, int32_t* temp, int32_t* aux);
196    static void volumeStereo(track_t* t, int32_t* out, size_t frameCount, int32_t* temp, int32_t* aux);
197
198    static void process__validate(state_t* state);
199    static void process__nop(state_t* state);
200    static void process__genericNoResampling(state_t* state);
201    static void process__genericResampling(state_t* state);
202    static void process__OneTrack16BitsStereoNoResampling(state_t* state);
203    static void process__TwoTracks16BitsStereoNoResampling(state_t* state);
204};
205
206// ----------------------------------------------------------------------------
207}; // namespace android
208
209#endif // ANDROID_AUDIO_MIXER_H
210