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      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 <map>
     22 #include <pthread.h>
     23 #include <sstream>
     24 #include <stdint.h>
     25 #include <sys/types.h>
     26 #include <unordered_map>
     27 #include <vector>
     28 
     29 #include <android/os/IExternalVibratorService.h>
     30 #include <media/AudioBufferProvider.h>
     31 #include <media/AudioResampler.h>
     32 #include <media/AudioResamplerPublic.h>
     33 #include <media/BufferProviders.h>
     34 #include <system/audio.h>
     35 #include <utils/Compat.h>
     36 #include <utils/threads.h>
     37 
     38 // FIXME This is actually unity gain, which might not be max in future, expressed in U.12
     39 #define MAX_GAIN_INT AudioMixer::UNITY_GAIN_INT
     40 
     41 // This must match frameworks/av/services/audioflinger/Configuration.h
     42 #define FLOAT_AUX
     43 
     44 namespace android {
     45 
     46 namespace NBLog {
     47 class Writer;
     48 }   // namespace NBLog
     49 
     50 // ----------------------------------------------------------------------------
     51 
     52 class AudioMixer
     53 {
     54 public:
     55     // Do not change these unless underlying code changes.
     56     // This mixer has a hard-coded upper limit of 8 channels for output.
     57     static constexpr uint32_t MAX_NUM_CHANNELS = FCC_8;
     58     static constexpr uint32_t MAX_NUM_VOLUMES = FCC_2; // stereo volume only
     59     // maximum number of channels supported for the content
     60     static const uint32_t MAX_NUM_CHANNELS_TO_DOWNMIX = AUDIO_CHANNEL_COUNT_MAX;
     61 
     62     static const uint16_t UNITY_GAIN_INT = 0x1000;
     63     static const CONSTEXPR float UNITY_GAIN_FLOAT = 1.0f;
     64 
     65     enum { // names
     66         // setParameter targets
     67         TRACK           = 0x3000,
     68         RESAMPLE        = 0x3001,
     69         RAMP_VOLUME     = 0x3002, // ramp to new volume
     70         VOLUME          = 0x3003, // don't ramp
     71         TIMESTRETCH     = 0x3004,
     72 
     73         // set Parameter names
     74         // for target TRACK
     75         CHANNEL_MASK    = 0x4000,
     76         FORMAT          = 0x4001,
     77         MAIN_BUFFER     = 0x4002,
     78         AUX_BUFFER      = 0x4003,
     79         DOWNMIX_TYPE    = 0X4004,
     80         MIXER_FORMAT    = 0x4005, // AUDIO_FORMAT_PCM_(FLOAT|16_BIT)
     81         MIXER_CHANNEL_MASK = 0x4006, // Channel mask for mixer output
     82         // for haptic
     83         HAPTIC_ENABLED  = 0x4007, // Set haptic data from this track should be played or not.
     84         HAPTIC_INTENSITY = 0x4008, // Set the intensity to play haptic data.
     85         // for target RESAMPLE
     86         SAMPLE_RATE     = 0x4100, // Configure sample rate conversion on this track name;
     87                                   // parameter 'value' is the new sample rate in Hz.
     88                                   // Only creates a sample rate converter the first time that
     89                                   // the track sample rate is different from the mix sample rate.
     90                                   // If the new sample rate is the same as the mix sample rate,
     91                                   // and a sample rate converter already exists,
     92                                   // then the sample rate converter remains present but is a no-op.
     93         RESET           = 0x4101, // Reset sample rate converter without changing sample rate.
     94                                   // This clears out the resampler's input buffer.
     95         REMOVE          = 0x4102, // Remove the sample rate converter on this track name;
     96                                   // the track is restored to the mix sample rate.
     97         // for target RAMP_VOLUME and VOLUME (8 channels max)
     98         // FIXME use float for these 3 to improve the dynamic range
     99         VOLUME0         = 0x4200,
    100         VOLUME1         = 0x4201,
    101         AUXLEVEL        = 0x4210,
    102         // for target TIMESTRETCH
    103         PLAYBACK_RATE   = 0x4300, // Configure timestretch on this track name;
    104                                   // parameter 'value' is a pointer to the new playback rate.
    105     };
    106 
    107     typedef enum { // Haptic intensity, should keep consistent with VibratorService
    108         HAPTIC_SCALE_MUTE = os::IExternalVibratorService::SCALE_MUTE,
    109         HAPTIC_SCALE_VERY_LOW = os::IExternalVibratorService::SCALE_VERY_LOW,
    110         HAPTIC_SCALE_LOW = os::IExternalVibratorService::SCALE_LOW,
    111         HAPTIC_SCALE_NONE = os::IExternalVibratorService::SCALE_NONE,
    112         HAPTIC_SCALE_HIGH = os::IExternalVibratorService::SCALE_HIGH,
    113         HAPTIC_SCALE_VERY_HIGH = os::IExternalVibratorService::SCALE_VERY_HIGH,
    114     } haptic_intensity_t;
    115     static constexpr float HAPTIC_SCALE_VERY_LOW_RATIO = 2.0f / 3.0f;
    116     static constexpr float HAPTIC_SCALE_LOW_RATIO = 3.0f / 4.0f;
    117     static const constexpr float HAPTIC_MAX_AMPLITUDE_FLOAT = 1.0f;
    118 
    119     static inline bool isValidHapticIntensity(haptic_intensity_t hapticIntensity) {
    120         switch (hapticIntensity) {
    121         case HAPTIC_SCALE_MUTE:
    122         case HAPTIC_SCALE_VERY_LOW:
    123         case HAPTIC_SCALE_LOW:
    124         case HAPTIC_SCALE_NONE:
    125         case HAPTIC_SCALE_HIGH:
    126         case HAPTIC_SCALE_VERY_HIGH:
    127             return true;
    128         default:
    129             return false;
    130         }
    131     }
    132 
    133     AudioMixer(size_t frameCount, uint32_t sampleRate)
    134         : mSampleRate(sampleRate)
    135         , mFrameCount(frameCount) {
    136         pthread_once(&sOnceControl, &sInitRoutine);
    137     }
    138 
    139     // Create a new track in the mixer.
    140     //
    141     // \param name        a unique user-provided integer associated with the track.
    142     //                    If name already exists, the function will abort.
    143     // \param channelMask output channel mask.
    144     // \param format      PCM format
    145     // \param sessionId   Session id for the track. Tracks with the same
    146     //                    session id will be submixed together.
    147     //
    148     // \return OK        on success.
    149     //         BAD_VALUE if the format does not satisfy isValidFormat()
    150     //                   or the channelMask does not satisfy isValidChannelMask().
    151     status_t    create(
    152             int name, audio_channel_mask_t channelMask, audio_format_t format, int sessionId);
    153 
    154     bool        exists(int name) const {
    155         return mTracks.count(name) > 0;
    156     }
    157 
    158     // Free an allocated track by name.
    159     void        destroy(int name);
    160 
    161     // Enable or disable an allocated track by name
    162     void        enable(int name);
    163     void        disable(int name);
    164 
    165     void        setParameter(int name, int target, int param, void *value);
    166 
    167     void        setBufferProvider(int name, AudioBufferProvider* bufferProvider);
    168 
    169     void        process() {
    170         for (const auto &pair : mTracks) {
    171             // Clear contracted buffer before processing if contracted channels are saved
    172             const std::shared_ptr<Track> &t = pair.second;
    173             if (t->mKeepContractedChannels) {
    174                 t->clearContractedBuffer();
    175             }
    176         }
    177         (this->*mHook)();
    178         processHapticData();
    179     }
    180 
    181     size_t      getUnreleasedFrames(int name) const;
    182 
    183     std::string trackNames() const {
    184         std::stringstream ss;
    185         for (const auto &pair : mTracks) {
    186             ss << pair.first << " ";
    187         }
    188         return ss.str();
    189     }
    190 
    191     void        setNBLogWriter(NBLog::Writer *logWriter) {
    192         mNBLogWriter = logWriter;
    193     }
    194 
    195     static inline bool isValidFormat(audio_format_t format) {
    196         switch (format) {
    197         case AUDIO_FORMAT_PCM_8_BIT:
    198         case AUDIO_FORMAT_PCM_16_BIT:
    199         case AUDIO_FORMAT_PCM_24_BIT_PACKED:
    200         case AUDIO_FORMAT_PCM_32_BIT:
    201         case AUDIO_FORMAT_PCM_FLOAT:
    202             return true;
    203         default:
    204             return false;
    205         }
    206     }
    207 
    208     static inline bool isValidChannelMask(audio_channel_mask_t channelMask) {
    209         return audio_channel_mask_is_valid(channelMask); // the RemixBufferProvider is flexible.
    210     }
    211 
    212 private:
    213 
    214     /* For multi-format functions (calls template functions
    215      * in AudioMixerOps.h).  The template parameters are as follows:
    216      *
    217      *   MIXTYPE     (see AudioMixerOps.h MIXTYPE_* enumeration)
    218      *   USEFLOATVOL (set to true if float volume is used)
    219      *   ADJUSTVOL   (set to true if volume ramp parameters needs adjustment afterwards)
    220      *   TO: int32_t (Q4.27) or float
    221      *   TI: int32_t (Q4.27) or int16_t (Q0.15) or float
    222      *   TA: int32_t (Q4.27)
    223      */
    224 
    225     enum {
    226         // FIXME this representation permits up to 8 channels
    227         NEEDS_CHANNEL_COUNT__MASK   = 0x00000007,
    228     };
    229 
    230     enum {
    231         NEEDS_CHANNEL_1             = 0x00000000,   // mono
    232         NEEDS_CHANNEL_2             = 0x00000001,   // stereo
    233 
    234         // sample format is not explicitly specified, and is assumed to be AUDIO_FORMAT_PCM_16_BIT
    235 
    236         NEEDS_MUTE                  = 0x00000100,
    237         NEEDS_RESAMPLE              = 0x00001000,
    238         NEEDS_AUX                   = 0x00010000,
    239     };
    240 
    241     // hook types
    242     enum {
    243         PROCESSTYPE_NORESAMPLEONETRACK, // others set elsewhere
    244     };
    245 
    246     enum {
    247         TRACKTYPE_NOP,
    248         TRACKTYPE_RESAMPLE,
    249         TRACKTYPE_NORESAMPLE,
    250         TRACKTYPE_NORESAMPLEMONO,
    251     };
    252 
    253     // process hook functionality
    254     using process_hook_t = void(AudioMixer::*)();
    255 
    256     struct Track;
    257     using hook_t = void(Track::*)(int32_t* output, size_t numOutFrames, int32_t* temp, int32_t* aux);
    258 
    259     struct Track {
    260         Track()
    261             : bufferProvider(nullptr)
    262         {
    263             // TODO: move additional initialization here.
    264         }
    265 
    266         ~Track()
    267         {
    268             // bufferProvider, mInputBufferProvider need not be deleted.
    269             mResampler.reset(nullptr);
    270             // Ensure the order of destruction of buffer providers as they
    271             // release the upstream provider in the destructor.
    272             mTimestretchBufferProvider.reset(nullptr);
    273             mPostDownmixReformatBufferProvider.reset(nullptr);
    274             mDownmixerBufferProvider.reset(nullptr);
    275             mReformatBufferProvider.reset(nullptr);
    276             mContractChannelsNonDestructiveBufferProvider.reset(nullptr);
    277             mAdjustChannelsBufferProvider.reset(nullptr);
    278         }
    279 
    280         bool        needsRamp() { return (volumeInc[0] | volumeInc[1] | auxInc) != 0; }
    281         bool        setResampler(uint32_t trackSampleRate, uint32_t devSampleRate);
    282         bool        doesResample() const { return mResampler.get() != nullptr; }
    283         void        resetResampler() { if (mResampler.get() != nullptr) mResampler->reset(); }
    284         void        adjustVolumeRamp(bool aux, bool useFloat = false);
    285         size_t      getUnreleasedFrames() const { return mResampler.get() != nullptr ?
    286                                                     mResampler->getUnreleasedFrames() : 0; };
    287 
    288         status_t    prepareForDownmix();
    289         void        unprepareForDownmix();
    290         status_t    prepareForReformat();
    291         void        unprepareForReformat();
    292         status_t    prepareForAdjustChannels();
    293         void        unprepareForAdjustChannels();
    294         status_t    prepareForAdjustChannelsNonDestructive(size_t frames);
    295         void        unprepareForAdjustChannelsNonDestructive();
    296         void        clearContractedBuffer();
    297         bool        setPlaybackRate(const AudioPlaybackRate &playbackRate);
    298         void        reconfigureBufferProviders();
    299 
    300         static hook_t getTrackHook(int trackType, uint32_t channelCount,
    301                 audio_format_t mixerInFormat, audio_format_t mixerOutFormat);
    302 
    303         void track__nop(int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
    304 
    305         template <int MIXTYPE, bool USEFLOATVOL, bool ADJUSTVOL,
    306             typename TO, typename TI, typename TA>
    307         void volumeMix(TO *out, size_t outFrames, const TI *in, TA *aux, bool ramp);
    308 
    309         uint32_t    needs;
    310 
    311         // TODO: Eventually remove legacy integer volume settings
    312         union {
    313         int16_t     volume[MAX_NUM_VOLUMES]; // U4.12 fixed point (top bit should be zero)
    314         int32_t     volumeRL;
    315         };
    316 
    317         int32_t     prevVolume[MAX_NUM_VOLUMES];
    318         int32_t     volumeInc[MAX_NUM_VOLUMES];
    319         int32_t     auxInc;
    320         int32_t     prevAuxLevel;
    321         int16_t     auxLevel;       // 0 <= auxLevel <= MAX_GAIN_INT, but signed for mul performance
    322 
    323         uint16_t    frameCount;
    324 
    325         uint8_t     channelCount;   // 1 or 2, redundant with (needs & NEEDS_CHANNEL_COUNT__MASK)
    326         uint8_t     unused_padding; // formerly format, was always 16
    327         uint16_t    enabled;        // actually bool
    328         audio_channel_mask_t channelMask;
    329 
    330         // actual buffer provider used by the track hooks, see DownmixerBufferProvider below
    331         //  for how the Track buffer provider is wrapped by another one when dowmixing is required
    332         AudioBufferProvider*                bufferProvider;
    333 
    334         mutable AudioBufferProvider::Buffer buffer; // 8 bytes
    335 
    336         hook_t      hook;
    337         const void  *mIn;             // current location in buffer
    338 
    339         std::unique_ptr<AudioResampler> mResampler;
    340         uint32_t            sampleRate;
    341         int32_t*           mainBuffer;
    342         int32_t*           auxBuffer;
    343 
    344         /* Buffer providers are constructed to translate the track input data as needed.
    345          *
    346          * TODO: perhaps make a single PlaybackConverterProvider class to move
    347          * all pre-mixer track buffer conversions outside the AudioMixer class.
    348          *
    349          * 1) mInputBufferProvider: The AudioTrack buffer provider.
    350          * 2) mAdjustChannelsBufferProvider: Expands or contracts sample data from one interleaved
    351          *    channel format to another. Expanded channels are filled with zeros and put at the end
    352          *    of each audio frame. Contracted channels are copied to the end of the buffer.
    353          * 3) mContractChannelsNonDestructiveBufferProvider: Non-destructively contract sample data.
    354          *    This is currently using at audio-haptic coupled playback to separate audio and haptic
    355          *    data. Contracted channels could be written to given buffer.
    356          * 4) mReformatBufferProvider: If not NULL, performs the audio reformat to
    357          *    match either mMixerInFormat or mDownmixRequiresFormat, if the downmixer
    358          *    requires reformat. For example, it may convert floating point input to
    359          *    PCM_16_bit if that's required by the downmixer.
    360          * 5) mDownmixerBufferProvider: If not NULL, performs the channel remixing to match
    361          *    the number of channels required by the mixer sink.
    362          * 6) mPostDownmixReformatBufferProvider: If not NULL, performs reformatting from
    363          *    the downmixer requirements to the mixer engine input requirements.
    364          * 7) mTimestretchBufferProvider: Adds timestretching for playback rate
    365          */
    366         AudioBufferProvider*     mInputBufferProvider;    // externally provided buffer provider.
    367         // TODO: combine mAdjustChannelsBufferProvider and
    368         // mContractChannelsNonDestructiveBufferProvider
    369         std::unique_ptr<PassthruBufferProvider> mAdjustChannelsBufferProvider;
    370         std::unique_ptr<PassthruBufferProvider> mContractChannelsNonDestructiveBufferProvider;
    371         std::unique_ptr<PassthruBufferProvider> mReformatBufferProvider;
    372         std::unique_ptr<PassthruBufferProvider> mDownmixerBufferProvider;
    373         std::unique_ptr<PassthruBufferProvider> mPostDownmixReformatBufferProvider;
    374         std::unique_ptr<PassthruBufferProvider> mTimestretchBufferProvider;
    375 
    376         int32_t     sessionId;
    377 
    378         audio_format_t mMixerFormat;     // output mix format: AUDIO_FORMAT_PCM_(FLOAT|16_BIT)
    379         audio_format_t mFormat;          // input track format
    380         audio_format_t mMixerInFormat;   // mix internal format AUDIO_FORMAT_PCM_(FLOAT|16_BIT)
    381                                          // each track must be converted to this format.
    382         audio_format_t mDownmixRequiresFormat;  // required downmixer format
    383                                                 // AUDIO_FORMAT_PCM_16_BIT if 16 bit necessary
    384                                                 // AUDIO_FORMAT_INVALID if no required format
    385 
    386         float          mVolume[MAX_NUM_VOLUMES];     // floating point set volume
    387         float          mPrevVolume[MAX_NUM_VOLUMES]; // floating point previous volume
    388         float          mVolumeInc[MAX_NUM_VOLUMES];  // floating point volume increment
    389 
    390         float          mAuxLevel;                     // floating point set aux level
    391         float          mPrevAuxLevel;                 // floating point prev aux level
    392         float          mAuxInc;                       // floating point aux increment
    393 
    394         audio_channel_mask_t mMixerChannelMask;
    395         uint32_t             mMixerChannelCount;
    396 
    397         AudioPlaybackRate    mPlaybackRate;
    398 
    399         // Haptic
    400         bool                 mHapticPlaybackEnabled;
    401         haptic_intensity_t   mHapticIntensity;
    402         audio_channel_mask_t mHapticChannelMask;
    403         uint32_t             mHapticChannelCount;
    404         audio_channel_mask_t mMixerHapticChannelMask;
    405         uint32_t             mMixerHapticChannelCount;
    406         uint32_t             mAdjustInChannelCount;
    407         uint32_t             mAdjustOutChannelCount;
    408         uint32_t             mAdjustNonDestructiveInChannelCount;
    409         uint32_t             mAdjustNonDestructiveOutChannelCount;
    410         bool                 mKeepContractedChannels;
    411 
    412         float getHapticScaleGamma() const {
    413         // Need to keep consistent with the value in VibratorService.
    414         switch (mHapticIntensity) {
    415         case HAPTIC_SCALE_VERY_LOW:
    416             return 2.0f;
    417         case HAPTIC_SCALE_LOW:
    418             return 1.5f;
    419         case HAPTIC_SCALE_HIGH:
    420             return 0.5f;
    421         case HAPTIC_SCALE_VERY_HIGH:
    422             return 0.25f;
    423         default:
    424             return 1.0f;
    425         }
    426         }
    427 
    428         float getHapticMaxAmplitudeRatio() const {
    429         // Need to keep consistent with the value in VibratorService.
    430         switch (mHapticIntensity) {
    431         case HAPTIC_SCALE_VERY_LOW:
    432             return HAPTIC_SCALE_VERY_LOW_RATIO;
    433         case HAPTIC_SCALE_LOW:
    434             return HAPTIC_SCALE_LOW_RATIO;
    435         case HAPTIC_SCALE_NONE:
    436         case HAPTIC_SCALE_HIGH:
    437         case HAPTIC_SCALE_VERY_HIGH:
    438             return 1.0f;
    439         default:
    440             return 0.0f;
    441         }
    442         }
    443 
    444     private:
    445         // hooks
    446         void track__genericResample(int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
    447         void track__16BitsStereo(int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
    448         void track__16BitsMono(int32_t* out, size_t numFrames, int32_t* temp, int32_t* aux);
    449 
    450         void volumeRampStereo(int32_t* out, size_t frameCount, int32_t* temp, int32_t* aux);
    451         void volumeStereo(int32_t* out, size_t frameCount, int32_t* temp, int32_t* aux);
    452 
    453         // multi-format track hooks
    454         template <int MIXTYPE, typename TO, typename TI, typename TA>
    455         void track__Resample(TO* out, size_t frameCount, TO* temp __unused, TA* aux);
    456         template <int MIXTYPE, typename TO, typename TI, typename TA>
    457         void track__NoResample(TO* out, size_t frameCount, TO* temp __unused, TA* aux);
    458     };
    459 
    460     // TODO: remove BLOCKSIZE unit of processing - it isn't needed anymore.
    461     static constexpr int BLOCKSIZE = 16;
    462 
    463     bool setChannelMasks(int name,
    464             audio_channel_mask_t trackChannelMask, audio_channel_mask_t mixerChannelMask);
    465 
    466     // Called when track info changes and a new process hook should be determined.
    467     void invalidate() {
    468         mHook = &AudioMixer::process__validate;
    469     }
    470 
    471     void process__validate();
    472     void process__nop();
    473     void process__genericNoResampling();
    474     void process__genericResampling();
    475     void process__oneTrack16BitsStereoNoResampling();
    476 
    477     template <int MIXTYPE, typename TO, typename TI, typename TA>
    478     void process__noResampleOneTrack();
    479 
    480     void processHapticData();
    481 
    482     static process_hook_t getProcessHook(int processType, uint32_t channelCount,
    483             audio_format_t mixerInFormat, audio_format_t mixerOutFormat);
    484 
    485     static void convertMixerFormat(void *out, audio_format_t mixerOutFormat,
    486             void *in, audio_format_t mixerInFormat, size_t sampleCount);
    487 
    488     static void sInitRoutine();
    489 
    490     // initialization constants
    491     const uint32_t mSampleRate;
    492     const size_t mFrameCount;
    493 
    494     NBLog::Writer *mNBLogWriter = nullptr;   // associated NBLog::Writer
    495 
    496     process_hook_t mHook = &AudioMixer::process__nop;   // one of process__*, never nullptr
    497 
    498     // the size of the type (int32_t) should be the largest of all types supported
    499     // by the mixer.
    500     std::unique_ptr<int32_t[]> mOutputTemp;
    501     std::unique_ptr<int32_t[]> mResampleTemp;
    502 
    503     // track names grouped by main buffer, in no particular order of main buffer.
    504     // however names for a particular main buffer are in order (by construction).
    505     std::unordered_map<void * /* mainBuffer */, std::vector<int /* name */>> mGroups;
    506 
    507     // track names that are enabled, in increasing order (by construction).
    508     std::vector<int /* name */> mEnabled;
    509 
    510     // track smart pointers, by name, in increasing order of name.
    511     std::map<int /* name */, std::shared_ptr<Track>> mTracks;
    512 
    513     static pthread_once_t sOnceControl; // initialized in constructor by first new
    514 };
    515 
    516 // ----------------------------------------------------------------------------
    517 } // namespace android
    518 
    519 #endif // ANDROID_AUDIO_MIXER_H
    520