AudioMixer.cpp revision 9e0308c03d4e76d3146cbb6e30aeb3ac03f05cf5
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#define LOG_TAG "AudioMixer"
19//#define LOG_NDEBUG 0
20
21#include "Configuration.h"
22#include <stdint.h>
23#include <string.h>
24#include <stdlib.h>
25#include <sys/types.h>
26
27#include <utils/Errors.h>
28#include <utils/Log.h>
29
30#include <cutils/bitops.h>
31#include <cutils/compiler.h>
32#include <utils/Debug.h>
33
34#include <system/audio.h>
35
36#include <audio_utils/primitives.h>
37#include <common_time/local_clock.h>
38#include <common_time/cc_helper.h>
39
40#include <media/EffectsFactoryApi.h>
41
42#include "AudioMixer.h"
43
44namespace android {
45
46// ----------------------------------------------------------------------------
47AudioMixer::DownmixerBufferProvider::DownmixerBufferProvider() : AudioBufferProvider(),
48        mTrackBufferProvider(NULL), mDownmixHandle(NULL)
49{
50}
51
52AudioMixer::DownmixerBufferProvider::~DownmixerBufferProvider()
53{
54    ALOGV("AudioMixer deleting DownmixerBufferProvider (%p)", this);
55    EffectRelease(mDownmixHandle);
56}
57
58status_t AudioMixer::DownmixerBufferProvider::getNextBuffer(AudioBufferProvider::Buffer *pBuffer,
59        int64_t pts) {
60    //ALOGV("DownmixerBufferProvider::getNextBuffer()");
61    if (mTrackBufferProvider != NULL) {
62        status_t res = mTrackBufferProvider->getNextBuffer(pBuffer, pts);
63        if (res == OK) {
64            mDownmixConfig.inputCfg.buffer.frameCount = pBuffer->frameCount;
65            mDownmixConfig.inputCfg.buffer.raw = pBuffer->raw;
66            mDownmixConfig.outputCfg.buffer.frameCount = pBuffer->frameCount;
67            mDownmixConfig.outputCfg.buffer.raw = mDownmixConfig.inputCfg.buffer.raw;
68            // in-place so overwrite the buffer contents, has been set in prepareTrackForDownmix()
69            //mDownmixConfig.outputCfg.accessMode = EFFECT_BUFFER_ACCESS_WRITE;
70
71            res = (*mDownmixHandle)->process(mDownmixHandle,
72                    &mDownmixConfig.inputCfg.buffer, &mDownmixConfig.outputCfg.buffer);
73            //ALOGV("getNextBuffer is downmixing");
74        }
75        return res;
76    } else {
77        ALOGE("DownmixerBufferProvider::getNextBuffer() error: NULL track buffer provider");
78        return NO_INIT;
79    }
80}
81
82void AudioMixer::DownmixerBufferProvider::releaseBuffer(AudioBufferProvider::Buffer *pBuffer) {
83    //ALOGV("DownmixerBufferProvider::releaseBuffer()");
84    if (mTrackBufferProvider != NULL) {
85        mTrackBufferProvider->releaseBuffer(pBuffer);
86    } else {
87        ALOGE("DownmixerBufferProvider::releaseBuffer() error: NULL track buffer provider");
88    }
89}
90
91
92// ----------------------------------------------------------------------------
93bool AudioMixer::sIsMultichannelCapable = false;
94
95effect_descriptor_t AudioMixer::sDwnmFxDesc;
96
97// Ensure mConfiguredNames bitmask is initialized properly on all architectures.
98// The value of 1 << x is undefined in C when x >= 32.
99
100AudioMixer::AudioMixer(size_t frameCount, uint32_t sampleRate, uint32_t maxNumTracks)
101    :   mTrackNames(0), mConfiguredNames((maxNumTracks >= 32 ? 0 : 1 << maxNumTracks) - 1),
102        mSampleRate(sampleRate)
103{
104    // AudioMixer is not yet capable of multi-channel beyond stereo
105    COMPILE_TIME_ASSERT_FUNCTION_SCOPE(2 == MAX_NUM_CHANNELS);
106
107    ALOG_ASSERT(maxNumTracks <= MAX_NUM_TRACKS, "maxNumTracks %u > MAX_NUM_TRACKS %u",
108            maxNumTracks, MAX_NUM_TRACKS);
109
110    // AudioMixer is not yet capable of more than 32 active track inputs
111    ALOG_ASSERT(32 >= MAX_NUM_TRACKS, "bad MAX_NUM_TRACKS %d", MAX_NUM_TRACKS);
112
113    // AudioMixer is not yet capable of multi-channel output beyond stereo
114    ALOG_ASSERT(2 == MAX_NUM_CHANNELS, "bad MAX_NUM_CHANNELS %d", MAX_NUM_CHANNELS);
115
116    pthread_once(&sOnceControl, &sInitRoutine);
117
118    mState.enabledTracks= 0;
119    mState.needsChanged = 0;
120    mState.frameCount   = frameCount;
121    mState.hook         = process__nop;
122    mState.outputTemp   = NULL;
123    mState.resampleTemp = NULL;
124    mState.mLog         = &mDummyLog;
125    // mState.reserved
126
127    // FIXME Most of the following initialization is probably redundant since
128    // tracks[i] should only be referenced if (mTrackNames & (1 << i)) != 0
129    // and mTrackNames is initially 0.  However, leave it here until that's verified.
130    track_t* t = mState.tracks;
131    for (unsigned i=0 ; i < MAX_NUM_TRACKS ; i++) {
132        t->resampler = NULL;
133        t->downmixerBufferProvider = NULL;
134        t++;
135    }
136
137}
138
139AudioMixer::~AudioMixer()
140{
141    track_t* t = mState.tracks;
142    for (unsigned i=0 ; i < MAX_NUM_TRACKS ; i++) {
143        delete t->resampler;
144        delete t->downmixerBufferProvider;
145        t++;
146    }
147    delete [] mState.outputTemp;
148    delete [] mState.resampleTemp;
149}
150
151void AudioMixer::setLog(NBLog::Writer *log)
152{
153    mState.mLog = log;
154}
155
156int AudioMixer::getTrackName(audio_channel_mask_t channelMask, int sessionId)
157{
158    uint32_t names = (~mTrackNames) & mConfiguredNames;
159    if (names != 0) {
160        int n = __builtin_ctz(names);
161        ALOGV("add track (%d)", n);
162        mTrackNames |= 1 << n;
163        // assume default parameters for the track, except where noted below
164        track_t* t = &mState.tracks[n];
165        t->needs = 0;
166        t->volume[0] = UNITY_GAIN;
167        t->volume[1] = UNITY_GAIN;
168        // no initialization needed
169        // t->prevVolume[0]
170        // t->prevVolume[1]
171        t->volumeInc[0] = 0;
172        t->volumeInc[1] = 0;
173        t->auxLevel = 0;
174        t->auxInc = 0;
175        // no initialization needed
176        // t->prevAuxLevel
177        // t->frameCount
178        t->channelCount = 2;
179        t->enabled = false;
180        t->format = 16;
181        t->channelMask = AUDIO_CHANNEL_OUT_STEREO;
182        t->sessionId = sessionId;
183        // setBufferProvider(name, AudioBufferProvider *) is required before enable(name)
184        t->bufferProvider = NULL;
185        t->buffer.raw = NULL;
186        // no initialization needed
187        // t->buffer.frameCount
188        t->hook = NULL;
189        t->in = NULL;
190        t->resampler = NULL;
191        t->sampleRate = mSampleRate;
192        // setParameter(name, TRACK, MAIN_BUFFER, mixBuffer) is required before enable(name)
193        t->mainBuffer = NULL;
194        t->auxBuffer = NULL;
195        t->downmixerBufferProvider = NULL;
196
197        status_t status = initTrackDownmix(&mState.tracks[n], n, channelMask);
198        if (status == OK) {
199            return TRACK0 + n;
200        }
201        ALOGE("AudioMixer::getTrackName(0x%x) failed, error preparing track for downmix",
202                channelMask);
203    }
204    return -1;
205}
206
207void AudioMixer::invalidateState(uint32_t mask)
208{
209    if (mask != 0) {
210        mState.needsChanged |= mask;
211        mState.hook = process__validate;
212    }
213 }
214
215status_t AudioMixer::initTrackDownmix(track_t* pTrack, int trackNum, audio_channel_mask_t mask)
216{
217    uint32_t channelCount = popcount(mask);
218    ALOG_ASSERT((channelCount <= MAX_NUM_CHANNELS_TO_DOWNMIX) && channelCount);
219    status_t status = OK;
220    if (channelCount > MAX_NUM_CHANNELS) {
221        pTrack->channelMask = mask;
222        pTrack->channelCount = channelCount;
223        ALOGV("initTrackDownmix(track=%d, mask=0x%x) calls prepareTrackForDownmix()",
224                trackNum, mask);
225        status = prepareTrackForDownmix(pTrack, trackNum);
226    } else {
227        unprepareTrackForDownmix(pTrack, trackNum);
228    }
229    return status;
230}
231
232void AudioMixer::unprepareTrackForDownmix(track_t* pTrack, int trackName __unused) {
233    ALOGV("AudioMixer::unprepareTrackForDownmix(%d)", trackName);
234
235    if (pTrack->downmixerBufferProvider != NULL) {
236        // this track had previously been configured with a downmixer, delete it
237        ALOGV(" deleting old downmixer");
238        pTrack->bufferProvider = pTrack->downmixerBufferProvider->mTrackBufferProvider;
239        delete pTrack->downmixerBufferProvider;
240        pTrack->downmixerBufferProvider = NULL;
241    } else {
242        ALOGV(" nothing to do, no downmixer to delete");
243    }
244}
245
246status_t AudioMixer::prepareTrackForDownmix(track_t* pTrack, int trackName)
247{
248    ALOGV("AudioMixer::prepareTrackForDownmix(%d) with mask 0x%x", trackName, pTrack->channelMask);
249
250    // discard the previous downmixer if there was one
251    unprepareTrackForDownmix(pTrack, trackName);
252
253    DownmixerBufferProvider* pDbp = new DownmixerBufferProvider();
254    int32_t status;
255
256    if (!sIsMultichannelCapable) {
257        ALOGE("prepareTrackForDownmix(%d) fails: mixer doesn't support multichannel content",
258                trackName);
259        goto noDownmixForActiveTrack;
260    }
261
262    if (EffectCreate(&sDwnmFxDesc.uuid,
263            pTrack->sessionId /*sessionId*/, -2 /*ioId not relevant here, using random value*/,
264            &pDbp->mDownmixHandle/*pHandle*/) != 0) {
265        ALOGE("prepareTrackForDownmix(%d) fails: error creating downmixer effect", trackName);
266        goto noDownmixForActiveTrack;
267    }
268
269    // channel input configuration will be overridden per-track
270    pDbp->mDownmixConfig.inputCfg.channels = pTrack->channelMask;
271    pDbp->mDownmixConfig.outputCfg.channels = AUDIO_CHANNEL_OUT_STEREO;
272    pDbp->mDownmixConfig.inputCfg.format = AUDIO_FORMAT_PCM_16_BIT;
273    pDbp->mDownmixConfig.outputCfg.format = AUDIO_FORMAT_PCM_16_BIT;
274    pDbp->mDownmixConfig.inputCfg.samplingRate = pTrack->sampleRate;
275    pDbp->mDownmixConfig.outputCfg.samplingRate = pTrack->sampleRate;
276    pDbp->mDownmixConfig.inputCfg.accessMode = EFFECT_BUFFER_ACCESS_READ;
277    pDbp->mDownmixConfig.outputCfg.accessMode = EFFECT_BUFFER_ACCESS_WRITE;
278    // input and output buffer provider, and frame count will not be used as the downmix effect
279    // process() function is called directly (see DownmixerBufferProvider::getNextBuffer())
280    pDbp->mDownmixConfig.inputCfg.mask = EFFECT_CONFIG_SMP_RATE | EFFECT_CONFIG_CHANNELS |
281            EFFECT_CONFIG_FORMAT | EFFECT_CONFIG_ACC_MODE;
282    pDbp->mDownmixConfig.outputCfg.mask = pDbp->mDownmixConfig.inputCfg.mask;
283
284    {// scope for local variables that are not used in goto label "noDownmixForActiveTrack"
285        int cmdStatus;
286        uint32_t replySize = sizeof(int);
287
288        // Configure and enable downmixer
289        status = (*pDbp->mDownmixHandle)->command(pDbp->mDownmixHandle,
290                EFFECT_CMD_SET_CONFIG /*cmdCode*/, sizeof(effect_config_t) /*cmdSize*/,
291                &pDbp->mDownmixConfig /*pCmdData*/,
292                &replySize /*replySize*/, &cmdStatus /*pReplyData*/);
293        if ((status != 0) || (cmdStatus != 0)) {
294            ALOGE("error %d while configuring downmixer for track %d", status, trackName);
295            goto noDownmixForActiveTrack;
296        }
297        replySize = sizeof(int);
298        status = (*pDbp->mDownmixHandle)->command(pDbp->mDownmixHandle,
299                EFFECT_CMD_ENABLE /*cmdCode*/, 0 /*cmdSize*/, NULL /*pCmdData*/,
300                &replySize /*replySize*/, &cmdStatus /*pReplyData*/);
301        if ((status != 0) || (cmdStatus != 0)) {
302            ALOGE("error %d while enabling downmixer for track %d", status, trackName);
303            goto noDownmixForActiveTrack;
304        }
305
306        // Set downmix type
307        // parameter size rounded for padding on 32bit boundary
308        const int psizePadded = ((sizeof(downmix_params_t) - 1)/sizeof(int) + 1) * sizeof(int);
309        const int downmixParamSize =
310                sizeof(effect_param_t) + psizePadded + sizeof(downmix_type_t);
311        effect_param_t * const param = (effect_param_t *) malloc(downmixParamSize);
312        param->psize = sizeof(downmix_params_t);
313        const downmix_params_t downmixParam = DOWNMIX_PARAM_TYPE;
314        memcpy(param->data, &downmixParam, param->psize);
315        const downmix_type_t downmixType = DOWNMIX_TYPE_FOLD;
316        param->vsize = sizeof(downmix_type_t);
317        memcpy(param->data + psizePadded, &downmixType, param->vsize);
318
319        status = (*pDbp->mDownmixHandle)->command(pDbp->mDownmixHandle,
320                EFFECT_CMD_SET_PARAM /* cmdCode */, downmixParamSize/* cmdSize */,
321                param /*pCmndData*/, &replySize /*replySize*/, &cmdStatus /*pReplyData*/);
322
323        free(param);
324
325        if ((status != 0) || (cmdStatus != 0)) {
326            ALOGE("error %d while setting downmix type for track %d", status, trackName);
327            goto noDownmixForActiveTrack;
328        } else {
329            ALOGV("downmix type set to %d for track %d", (int) downmixType, trackName);
330        }
331    }// end of scope for local variables that are not used in goto label "noDownmixForActiveTrack"
332
333    // initialization successful:
334    // - keep track of the real buffer provider in case it was set before
335    pDbp->mTrackBufferProvider = pTrack->bufferProvider;
336    // - we'll use the downmix effect integrated inside this
337    //    track's buffer provider, and we'll use it as the track's buffer provider
338    pTrack->downmixerBufferProvider = pDbp;
339    pTrack->bufferProvider = pDbp;
340
341    return NO_ERROR;
342
343noDownmixForActiveTrack:
344    delete pDbp;
345    pTrack->downmixerBufferProvider = NULL;
346    return NO_INIT;
347}
348
349void AudioMixer::deleteTrackName(int name)
350{
351    ALOGV("AudioMixer::deleteTrackName(%d)", name);
352    name -= TRACK0;
353    ALOG_ASSERT(uint32_t(name) < MAX_NUM_TRACKS, "bad track name %d", name);
354    ALOGV("deleteTrackName(%d)", name);
355    track_t& track(mState.tracks[ name ]);
356    if (track.enabled) {
357        track.enabled = false;
358        invalidateState(1<<name);
359    }
360    // delete the resampler
361    delete track.resampler;
362    track.resampler = NULL;
363    // delete the downmixer
364    unprepareTrackForDownmix(&mState.tracks[name], name);
365
366    mTrackNames &= ~(1<<name);
367}
368
369void AudioMixer::enable(int name)
370{
371    name -= TRACK0;
372    ALOG_ASSERT(uint32_t(name) < MAX_NUM_TRACKS, "bad track name %d", name);
373    track_t& track = mState.tracks[name];
374
375    if (!track.enabled) {
376        track.enabled = true;
377        ALOGV("enable(%d)", name);
378        invalidateState(1 << name);
379    }
380}
381
382void AudioMixer::disable(int name)
383{
384    name -= TRACK0;
385    ALOG_ASSERT(uint32_t(name) < MAX_NUM_TRACKS, "bad track name %d", name);
386    track_t& track = mState.tracks[name];
387
388    if (track.enabled) {
389        track.enabled = false;
390        ALOGV("disable(%d)", name);
391        invalidateState(1 << name);
392    }
393}
394
395void AudioMixer::setParameter(int name, int target, int param, void *value)
396{
397    name -= TRACK0;
398    ALOG_ASSERT(uint32_t(name) < MAX_NUM_TRACKS, "bad track name %d", name);
399    track_t& track = mState.tracks[name];
400
401    int valueInt = (int)value;
402    int32_t *valueBuf = (int32_t *)value;
403
404    switch (target) {
405
406    case TRACK:
407        switch (param) {
408        case CHANNEL_MASK: {
409            audio_channel_mask_t mask = (audio_channel_mask_t) value;
410            if (track.channelMask != mask) {
411                uint32_t channelCount = popcount(mask);
412                ALOG_ASSERT((channelCount <= MAX_NUM_CHANNELS_TO_DOWNMIX) && channelCount);
413                track.channelMask = mask;
414                track.channelCount = channelCount;
415                // the mask has changed, does this track need a downmixer?
416                initTrackDownmix(&mState.tracks[name], name, mask);
417                ALOGV("setParameter(TRACK, CHANNEL_MASK, %x)", mask);
418                invalidateState(1 << name);
419            }
420            } break;
421        case MAIN_BUFFER:
422            if (track.mainBuffer != valueBuf) {
423                track.mainBuffer = valueBuf;
424                ALOGV("setParameter(TRACK, MAIN_BUFFER, %p)", valueBuf);
425                invalidateState(1 << name);
426            }
427            break;
428        case AUX_BUFFER:
429            if (track.auxBuffer != valueBuf) {
430                track.auxBuffer = valueBuf;
431                ALOGV("setParameter(TRACK, AUX_BUFFER, %p)", valueBuf);
432                invalidateState(1 << name);
433            }
434            break;
435        case FORMAT:
436            ALOG_ASSERT(valueInt == AUDIO_FORMAT_PCM_16_BIT);
437            break;
438        // FIXME do we want to support setting the downmix type from AudioFlinger?
439        //         for a specific track? or per mixer?
440        /* case DOWNMIX_TYPE:
441            break          */
442        default:
443            LOG_FATAL("bad param");
444        }
445        break;
446
447    case RESAMPLE:
448        switch (param) {
449        case SAMPLE_RATE:
450            ALOG_ASSERT(valueInt > 0, "bad sample rate %d", valueInt);
451            if (track.setResampler(uint32_t(valueInt), mSampleRate)) {
452                ALOGV("setParameter(RESAMPLE, SAMPLE_RATE, %u)",
453                        uint32_t(valueInt));
454                invalidateState(1 << name);
455            }
456            break;
457        case RESET:
458            track.resetResampler();
459            invalidateState(1 << name);
460            break;
461        case REMOVE:
462            delete track.resampler;
463            track.resampler = NULL;
464            track.sampleRate = mSampleRate;
465            invalidateState(1 << name);
466            break;
467        default:
468            LOG_FATAL("bad param");
469        }
470        break;
471
472    case RAMP_VOLUME:
473    case VOLUME:
474        switch (param) {
475        case VOLUME0:
476        case VOLUME1:
477            if (track.volume[param-VOLUME0] != valueInt) {
478                ALOGV("setParameter(VOLUME, VOLUME0/1: %04x)", valueInt);
479                track.prevVolume[param-VOLUME0] = track.volume[param-VOLUME0] << 16;
480                track.volume[param-VOLUME0] = valueInt;
481                if (target == VOLUME) {
482                    track.prevVolume[param-VOLUME0] = valueInt << 16;
483                    track.volumeInc[param-VOLUME0] = 0;
484                } else {
485                    int32_t d = (valueInt<<16) - track.prevVolume[param-VOLUME0];
486                    int32_t volInc = d / int32_t(mState.frameCount);
487                    track.volumeInc[param-VOLUME0] = volInc;
488                    if (volInc == 0) {
489                        track.prevVolume[param-VOLUME0] = valueInt << 16;
490                    }
491                }
492                invalidateState(1 << name);
493            }
494            break;
495        case AUXLEVEL:
496            //ALOG_ASSERT(0 <= valueInt && valueInt <= MAX_GAIN_INT, "bad aux level %d", valueInt);
497            if (track.auxLevel != valueInt) {
498                ALOGV("setParameter(VOLUME, AUXLEVEL: %04x)", valueInt);
499                track.prevAuxLevel = track.auxLevel << 16;
500                track.auxLevel = valueInt;
501                if (target == VOLUME) {
502                    track.prevAuxLevel = valueInt << 16;
503                    track.auxInc = 0;
504                } else {
505                    int32_t d = (valueInt<<16) - track.prevAuxLevel;
506                    int32_t volInc = d / int32_t(mState.frameCount);
507                    track.auxInc = volInc;
508                    if (volInc == 0) {
509                        track.prevAuxLevel = valueInt << 16;
510                    }
511                }
512                invalidateState(1 << name);
513            }
514            break;
515        default:
516            LOG_FATAL("bad param");
517        }
518        break;
519
520    default:
521        LOG_FATAL("bad target");
522    }
523}
524
525bool AudioMixer::track_t::setResampler(uint32_t value, uint32_t devSampleRate)
526{
527    if (value != devSampleRate || resampler != NULL) {
528        if (sampleRate != value) {
529            sampleRate = value;
530            if (resampler == NULL) {
531                ALOGV("creating resampler from track %d Hz to device %d Hz", value, devSampleRate);
532                AudioResampler::src_quality quality;
533                // force lowest quality level resampler if use case isn't music or video
534                // FIXME this is flawed for dynamic sample rates, as we choose the resampler
535                // quality level based on the initial ratio, but that could change later.
536                // Should have a way to distinguish tracks with static ratios vs. dynamic ratios.
537                if (!((value == 44100 && devSampleRate == 48000) ||
538                      (value == 48000 && devSampleRate == 44100))) {
539                    quality = AudioResampler::DYN_LOW_QUALITY;
540                } else {
541                    quality = AudioResampler::DEFAULT_QUALITY;
542                }
543                resampler = AudioResampler::create(
544                        format,
545                        // the resampler sees the number of channels after the downmixer, if any
546                        (int) (downmixerBufferProvider != NULL ? MAX_NUM_CHANNELS : channelCount),
547                        devSampleRate, quality);
548                resampler->setLocalTimeFreq(sLocalTimeFreq);
549            }
550            return true;
551        }
552    }
553    return false;
554}
555
556inline
557void AudioMixer::track_t::adjustVolumeRamp(bool aux)
558{
559    for (uint32_t i=0 ; i<MAX_NUM_CHANNELS ; i++) {
560        if (((volumeInc[i]>0) && (((prevVolume[i]+volumeInc[i])>>16) >= volume[i])) ||
561            ((volumeInc[i]<0) && (((prevVolume[i]+volumeInc[i])>>16) <= volume[i]))) {
562            volumeInc[i] = 0;
563            prevVolume[i] = volume[i]<<16;
564        }
565    }
566    if (aux) {
567        if (((auxInc>0) && (((prevAuxLevel+auxInc)>>16) >= auxLevel)) ||
568            ((auxInc<0) && (((prevAuxLevel+auxInc)>>16) <= auxLevel))) {
569            auxInc = 0;
570            prevAuxLevel = auxLevel<<16;
571        }
572    }
573}
574
575size_t AudioMixer::getUnreleasedFrames(int name) const
576{
577    name -= TRACK0;
578    if (uint32_t(name) < MAX_NUM_TRACKS) {
579        return mState.tracks[name].getUnreleasedFrames();
580    }
581    return 0;
582}
583
584void AudioMixer::setBufferProvider(int name, AudioBufferProvider* bufferProvider)
585{
586    name -= TRACK0;
587    ALOG_ASSERT(uint32_t(name) < MAX_NUM_TRACKS, "bad track name %d", name);
588
589    if (mState.tracks[name].downmixerBufferProvider != NULL) {
590        // update required?
591        if (mState.tracks[name].downmixerBufferProvider->mTrackBufferProvider != bufferProvider) {
592            ALOGV("AudioMixer::setBufferProvider(%p) for downmix", bufferProvider);
593            // setting the buffer provider for a track that gets downmixed consists in:
594            //  1/ setting the buffer provider to the "downmix / buffer provider" wrapper
595            //     so it's the one that gets called when the buffer provider is needed,
596            mState.tracks[name].bufferProvider = mState.tracks[name].downmixerBufferProvider;
597            //  2/ saving the buffer provider for the track so the wrapper can use it
598            //     when it downmixes.
599            mState.tracks[name].downmixerBufferProvider->mTrackBufferProvider = bufferProvider;
600        }
601    } else {
602        mState.tracks[name].bufferProvider = bufferProvider;
603    }
604}
605
606
607void AudioMixer::process(int64_t pts)
608{
609    mState.hook(&mState, pts);
610}
611
612
613void AudioMixer::process__validate(state_t* state, int64_t pts)
614{
615    ALOGW_IF(!state->needsChanged,
616        "in process__validate() but nothing's invalid");
617
618    uint32_t changed = state->needsChanged;
619    state->needsChanged = 0; // clear the validation flag
620
621    // recompute which tracks are enabled / disabled
622    uint32_t enabled = 0;
623    uint32_t disabled = 0;
624    while (changed) {
625        const int i = 31 - __builtin_clz(changed);
626        const uint32_t mask = 1<<i;
627        changed &= ~mask;
628        track_t& t = state->tracks[i];
629        (t.enabled ? enabled : disabled) |= mask;
630    }
631    state->enabledTracks &= ~disabled;
632    state->enabledTracks |=  enabled;
633
634    // compute everything we need...
635    int countActiveTracks = 0;
636    bool all16BitsStereoNoResample = true;
637    bool resampling = false;
638    bool volumeRamp = false;
639    uint32_t en = state->enabledTracks;
640    while (en) {
641        const int i = 31 - __builtin_clz(en);
642        en &= ~(1<<i);
643
644        countActiveTracks++;
645        track_t& t = state->tracks[i];
646        uint32_t n = 0;
647        // FIXME can overflow (mask is only 3 bits)
648        n |= NEEDS_CHANNEL_1 + t.channelCount - 1;
649        if (t.doesResample()) {
650            n |= NEEDS_RESAMPLE;
651        }
652        if (t.auxLevel != 0 && t.auxBuffer != NULL) {
653            n |= NEEDS_AUX;
654        }
655
656        if (t.volumeInc[0]|t.volumeInc[1]) {
657            volumeRamp = true;
658        } else if (!t.doesResample() && t.volumeRL == 0) {
659            n |= NEEDS_MUTE;
660        }
661        t.needs = n;
662
663        if (n & NEEDS_MUTE) {
664            t.hook = track__nop;
665        } else {
666            if (n & NEEDS_AUX) {
667                all16BitsStereoNoResample = false;
668            }
669            if (n & NEEDS_RESAMPLE) {
670                all16BitsStereoNoResample = false;
671                resampling = true;
672                t.hook = track__genericResample;
673                ALOGV_IF((n & NEEDS_CHANNEL_COUNT__MASK) > NEEDS_CHANNEL_2,
674                        "Track %d needs downmix + resample", i);
675            } else {
676                if ((n & NEEDS_CHANNEL_COUNT__MASK) == NEEDS_CHANNEL_1){
677                    t.hook = track__16BitsMono;
678                    all16BitsStereoNoResample = false;
679                }
680                if ((n & NEEDS_CHANNEL_COUNT__MASK) >= NEEDS_CHANNEL_2){
681                    t.hook = track__16BitsStereo;
682                    ALOGV_IF((n & NEEDS_CHANNEL_COUNT__MASK) > NEEDS_CHANNEL_2,
683                            "Track %d needs downmix", i);
684                }
685            }
686        }
687    }
688
689    // select the processing hooks
690    state->hook = process__nop;
691    if (countActiveTracks > 0) {
692        if (resampling) {
693            if (!state->outputTemp) {
694                state->outputTemp = new int32_t[MAX_NUM_CHANNELS * state->frameCount];
695            }
696            if (!state->resampleTemp) {
697                state->resampleTemp = new int32_t[MAX_NUM_CHANNELS * state->frameCount];
698            }
699            state->hook = process__genericResampling;
700        } else {
701            if (state->outputTemp) {
702                delete [] state->outputTemp;
703                state->outputTemp = NULL;
704            }
705            if (state->resampleTemp) {
706                delete [] state->resampleTemp;
707                state->resampleTemp = NULL;
708            }
709            state->hook = process__genericNoResampling;
710            if (all16BitsStereoNoResample && !volumeRamp) {
711                if (countActiveTracks == 1) {
712                    state->hook = process__OneTrack16BitsStereoNoResampling;
713                }
714            }
715        }
716    }
717
718    ALOGV("mixer configuration change: %d activeTracks (%08x) "
719        "all16BitsStereoNoResample=%d, resampling=%d, volumeRamp=%d",
720        countActiveTracks, state->enabledTracks,
721        all16BitsStereoNoResample, resampling, volumeRamp);
722
723   state->hook(state, pts);
724
725    // Now that the volume ramp has been done, set optimal state and
726    // track hooks for subsequent mixer process
727    if (countActiveTracks > 0) {
728        bool allMuted = true;
729        uint32_t en = state->enabledTracks;
730        while (en) {
731            const int i = 31 - __builtin_clz(en);
732            en &= ~(1<<i);
733            track_t& t = state->tracks[i];
734            if (!t.doesResample() && t.volumeRL == 0) {
735                t.needs |= NEEDS_MUTE;
736                t.hook = track__nop;
737            } else {
738                allMuted = false;
739            }
740        }
741        if (allMuted) {
742            state->hook = process__nop;
743        } else if (all16BitsStereoNoResample) {
744            if (countActiveTracks == 1) {
745                state->hook = process__OneTrack16BitsStereoNoResampling;
746            }
747        }
748    }
749}
750
751
752void AudioMixer::track__genericResample(track_t* t, int32_t* out, size_t outFrameCount,
753        int32_t* temp, int32_t* aux)
754{
755    t->resampler->setSampleRate(t->sampleRate);
756
757    // ramp gain - resample to temp buffer and scale/mix in 2nd step
758    if (aux != NULL) {
759        // always resample with unity gain when sending to auxiliary buffer to be able
760        // to apply send level after resampling
761        // TODO: modify each resampler to support aux channel?
762        t->resampler->setVolume(UNITY_GAIN, UNITY_GAIN);
763        memset(temp, 0, outFrameCount * MAX_NUM_CHANNELS * sizeof(int32_t));
764        t->resampler->resample(temp, outFrameCount, t->bufferProvider);
765        if (CC_UNLIKELY(t->volumeInc[0]|t->volumeInc[1]|t->auxInc)) {
766            volumeRampStereo(t, out, outFrameCount, temp, aux);
767        } else {
768            volumeStereo(t, out, outFrameCount, temp, aux);
769        }
770    } else {
771        if (CC_UNLIKELY(t->volumeInc[0]|t->volumeInc[1])) {
772            t->resampler->setVolume(UNITY_GAIN, UNITY_GAIN);
773            memset(temp, 0, outFrameCount * MAX_NUM_CHANNELS * sizeof(int32_t));
774            t->resampler->resample(temp, outFrameCount, t->bufferProvider);
775            volumeRampStereo(t, out, outFrameCount, temp, aux);
776        }
777
778        // constant gain
779        else {
780            t->resampler->setVolume(t->volume[0], t->volume[1]);
781            t->resampler->resample(out, outFrameCount, t->bufferProvider);
782        }
783    }
784}
785
786void AudioMixer::track__nop(track_t* t __unused, int32_t* out __unused,
787        size_t outFrameCount __unused, int32_t* temp __unused, int32_t* aux __unused)
788{
789}
790
791void AudioMixer::volumeRampStereo(track_t* t, int32_t* out, size_t frameCount, int32_t* temp,
792        int32_t* aux)
793{
794    int32_t vl = t->prevVolume[0];
795    int32_t vr = t->prevVolume[1];
796    const int32_t vlInc = t->volumeInc[0];
797    const int32_t vrInc = t->volumeInc[1];
798
799    //ALOGD("[0] %p: inc=%f, v0=%f, v1=%d, final=%f, count=%d",
800    //        t, vlInc/65536.0f, vl/65536.0f, t->volume[0],
801    //       (vl + vlInc*frameCount)/65536.0f, frameCount);
802
803    // ramp volume
804    if (CC_UNLIKELY(aux != NULL)) {
805        int32_t va = t->prevAuxLevel;
806        const int32_t vaInc = t->auxInc;
807        int32_t l;
808        int32_t r;
809
810        do {
811            l = (*temp++ >> 12);
812            r = (*temp++ >> 12);
813            *out++ += (vl >> 16) * l;
814            *out++ += (vr >> 16) * r;
815            *aux++ += (va >> 17) * (l + r);
816            vl += vlInc;
817            vr += vrInc;
818            va += vaInc;
819        } while (--frameCount);
820        t->prevAuxLevel = va;
821    } else {
822        do {
823            *out++ += (vl >> 16) * (*temp++ >> 12);
824            *out++ += (vr >> 16) * (*temp++ >> 12);
825            vl += vlInc;
826            vr += vrInc;
827        } while (--frameCount);
828    }
829    t->prevVolume[0] = vl;
830    t->prevVolume[1] = vr;
831    t->adjustVolumeRamp(aux != NULL);
832}
833
834void AudioMixer::volumeStereo(track_t* t, int32_t* out, size_t frameCount, int32_t* temp,
835        int32_t* aux)
836{
837    const int16_t vl = t->volume[0];
838    const int16_t vr = t->volume[1];
839
840    if (CC_UNLIKELY(aux != NULL)) {
841        const int16_t va = t->auxLevel;
842        do {
843            int16_t l = (int16_t)(*temp++ >> 12);
844            int16_t r = (int16_t)(*temp++ >> 12);
845            out[0] = mulAdd(l, vl, out[0]);
846            int16_t a = (int16_t)(((int32_t)l + r) >> 1);
847            out[1] = mulAdd(r, vr, out[1]);
848            out += 2;
849            aux[0] = mulAdd(a, va, aux[0]);
850            aux++;
851        } while (--frameCount);
852    } else {
853        do {
854            int16_t l = (int16_t)(*temp++ >> 12);
855            int16_t r = (int16_t)(*temp++ >> 12);
856            out[0] = mulAdd(l, vl, out[0]);
857            out[1] = mulAdd(r, vr, out[1]);
858            out += 2;
859        } while (--frameCount);
860    }
861}
862
863void AudioMixer::track__16BitsStereo(track_t* t, int32_t* out, size_t frameCount,
864        int32_t* temp __unused, int32_t* aux)
865{
866    const int16_t *in = static_cast<const int16_t *>(t->in);
867
868    if (CC_UNLIKELY(aux != NULL)) {
869        int32_t l;
870        int32_t r;
871        // ramp gain
872        if (CC_UNLIKELY(t->volumeInc[0]|t->volumeInc[1]|t->auxInc)) {
873            int32_t vl = t->prevVolume[0];
874            int32_t vr = t->prevVolume[1];
875            int32_t va = t->prevAuxLevel;
876            const int32_t vlInc = t->volumeInc[0];
877            const int32_t vrInc = t->volumeInc[1];
878            const int32_t vaInc = t->auxInc;
879            // ALOGD("[1] %p: inc=%f, v0=%f, v1=%d, final=%f, count=%d",
880            //        t, vlInc/65536.0f, vl/65536.0f, t->volume[0],
881            //        (vl + vlInc*frameCount)/65536.0f, frameCount);
882
883            do {
884                l = (int32_t)*in++;
885                r = (int32_t)*in++;
886                *out++ += (vl >> 16) * l;
887                *out++ += (vr >> 16) * r;
888                *aux++ += (va >> 17) * (l + r);
889                vl += vlInc;
890                vr += vrInc;
891                va += vaInc;
892            } while (--frameCount);
893
894            t->prevVolume[0] = vl;
895            t->prevVolume[1] = vr;
896            t->prevAuxLevel = va;
897            t->adjustVolumeRamp(true);
898        }
899
900        // constant gain
901        else {
902            const uint32_t vrl = t->volumeRL;
903            const int16_t va = (int16_t)t->auxLevel;
904            do {
905                uint32_t rl = *reinterpret_cast<const uint32_t *>(in);
906                int16_t a = (int16_t)(((int32_t)in[0] + in[1]) >> 1);
907                in += 2;
908                out[0] = mulAddRL(1, rl, vrl, out[0]);
909                out[1] = mulAddRL(0, rl, vrl, out[1]);
910                out += 2;
911                aux[0] = mulAdd(a, va, aux[0]);
912                aux++;
913            } while (--frameCount);
914        }
915    } else {
916        // ramp gain
917        if (CC_UNLIKELY(t->volumeInc[0]|t->volumeInc[1])) {
918            int32_t vl = t->prevVolume[0];
919            int32_t vr = t->prevVolume[1];
920            const int32_t vlInc = t->volumeInc[0];
921            const int32_t vrInc = t->volumeInc[1];
922
923            // ALOGD("[1] %p: inc=%f, v0=%f, v1=%d, final=%f, count=%d",
924            //        t, vlInc/65536.0f, vl/65536.0f, t->volume[0],
925            //        (vl + vlInc*frameCount)/65536.0f, frameCount);
926
927            do {
928                *out++ += (vl >> 16) * (int32_t) *in++;
929                *out++ += (vr >> 16) * (int32_t) *in++;
930                vl += vlInc;
931                vr += vrInc;
932            } while (--frameCount);
933
934            t->prevVolume[0] = vl;
935            t->prevVolume[1] = vr;
936            t->adjustVolumeRamp(false);
937        }
938
939        // constant gain
940        else {
941            const uint32_t vrl = t->volumeRL;
942            do {
943                uint32_t rl = *reinterpret_cast<const uint32_t *>(in);
944                in += 2;
945                out[0] = mulAddRL(1, rl, vrl, out[0]);
946                out[1] = mulAddRL(0, rl, vrl, out[1]);
947                out += 2;
948            } while (--frameCount);
949        }
950    }
951    t->in = in;
952}
953
954void AudioMixer::track__16BitsMono(track_t* t, int32_t* out, size_t frameCount,
955        int32_t* temp __unused, int32_t* aux)
956{
957    const int16_t *in = static_cast<int16_t const *>(t->in);
958
959    if (CC_UNLIKELY(aux != NULL)) {
960        // ramp gain
961        if (CC_UNLIKELY(t->volumeInc[0]|t->volumeInc[1]|t->auxInc)) {
962            int32_t vl = t->prevVolume[0];
963            int32_t vr = t->prevVolume[1];
964            int32_t va = t->prevAuxLevel;
965            const int32_t vlInc = t->volumeInc[0];
966            const int32_t vrInc = t->volumeInc[1];
967            const int32_t vaInc = t->auxInc;
968
969            // ALOGD("[2] %p: inc=%f, v0=%f, v1=%d, final=%f, count=%d",
970            //         t, vlInc/65536.0f, vl/65536.0f, t->volume[0],
971            //         (vl + vlInc*frameCount)/65536.0f, frameCount);
972
973            do {
974                int32_t l = *in++;
975                *out++ += (vl >> 16) * l;
976                *out++ += (vr >> 16) * l;
977                *aux++ += (va >> 16) * l;
978                vl += vlInc;
979                vr += vrInc;
980                va += vaInc;
981            } while (--frameCount);
982
983            t->prevVolume[0] = vl;
984            t->prevVolume[1] = vr;
985            t->prevAuxLevel = va;
986            t->adjustVolumeRamp(true);
987        }
988        // constant gain
989        else {
990            const int16_t vl = t->volume[0];
991            const int16_t vr = t->volume[1];
992            const int16_t va = (int16_t)t->auxLevel;
993            do {
994                int16_t l = *in++;
995                out[0] = mulAdd(l, vl, out[0]);
996                out[1] = mulAdd(l, vr, out[1]);
997                out += 2;
998                aux[0] = mulAdd(l, va, aux[0]);
999                aux++;
1000            } while (--frameCount);
1001        }
1002    } else {
1003        // ramp gain
1004        if (CC_UNLIKELY(t->volumeInc[0]|t->volumeInc[1])) {
1005            int32_t vl = t->prevVolume[0];
1006            int32_t vr = t->prevVolume[1];
1007            const int32_t vlInc = t->volumeInc[0];
1008            const int32_t vrInc = t->volumeInc[1];
1009
1010            // ALOGD("[2] %p: inc=%f, v0=%f, v1=%d, final=%f, count=%d",
1011            //         t, vlInc/65536.0f, vl/65536.0f, t->volume[0],
1012            //         (vl + vlInc*frameCount)/65536.0f, frameCount);
1013
1014            do {
1015                int32_t l = *in++;
1016                *out++ += (vl >> 16) * l;
1017                *out++ += (vr >> 16) * l;
1018                vl += vlInc;
1019                vr += vrInc;
1020            } while (--frameCount);
1021
1022            t->prevVolume[0] = vl;
1023            t->prevVolume[1] = vr;
1024            t->adjustVolumeRamp(false);
1025        }
1026        // constant gain
1027        else {
1028            const int16_t vl = t->volume[0];
1029            const int16_t vr = t->volume[1];
1030            do {
1031                int16_t l = *in++;
1032                out[0] = mulAdd(l, vl, out[0]);
1033                out[1] = mulAdd(l, vr, out[1]);
1034                out += 2;
1035            } while (--frameCount);
1036        }
1037    }
1038    t->in = in;
1039}
1040
1041// no-op case
1042void AudioMixer::process__nop(state_t* state, int64_t pts)
1043{
1044    uint32_t e0 = state->enabledTracks;
1045    size_t bufSize = state->frameCount * sizeof(int16_t) * MAX_NUM_CHANNELS;
1046    while (e0) {
1047        // process by group of tracks with same output buffer to
1048        // avoid multiple memset() on same buffer
1049        uint32_t e1 = e0, e2 = e0;
1050        int i = 31 - __builtin_clz(e1);
1051        {
1052            track_t& t1 = state->tracks[i];
1053            e2 &= ~(1<<i);
1054            while (e2) {
1055                i = 31 - __builtin_clz(e2);
1056                e2 &= ~(1<<i);
1057                track_t& t2 = state->tracks[i];
1058                if (CC_UNLIKELY(t2.mainBuffer != t1.mainBuffer)) {
1059                    e1 &= ~(1<<i);
1060                }
1061            }
1062            e0 &= ~(e1);
1063
1064            memset(t1.mainBuffer, 0, bufSize);
1065        }
1066
1067        while (e1) {
1068            i = 31 - __builtin_clz(e1);
1069            e1 &= ~(1<<i);
1070            {
1071                track_t& t3 = state->tracks[i];
1072                size_t outFrames = state->frameCount;
1073                while (outFrames) {
1074                    t3.buffer.frameCount = outFrames;
1075                    int64_t outputPTS = calculateOutputPTS(
1076                        t3, pts, state->frameCount - outFrames);
1077                    t3.bufferProvider->getNextBuffer(&t3.buffer, outputPTS);
1078                    if (t3.buffer.raw == NULL) break;
1079                    outFrames -= t3.buffer.frameCount;
1080                    t3.bufferProvider->releaseBuffer(&t3.buffer);
1081                }
1082            }
1083        }
1084    }
1085}
1086
1087// generic code without resampling
1088void AudioMixer::process__genericNoResampling(state_t* state, int64_t pts)
1089{
1090    int32_t outTemp[BLOCKSIZE * MAX_NUM_CHANNELS] __attribute__((aligned(32)));
1091
1092    // acquire each track's buffer
1093    uint32_t enabledTracks = state->enabledTracks;
1094    uint32_t e0 = enabledTracks;
1095    while (e0) {
1096        const int i = 31 - __builtin_clz(e0);
1097        e0 &= ~(1<<i);
1098        track_t& t = state->tracks[i];
1099        t.buffer.frameCount = state->frameCount;
1100        t.bufferProvider->getNextBuffer(&t.buffer, pts);
1101        t.frameCount = t.buffer.frameCount;
1102        t.in = t.buffer.raw;
1103    }
1104
1105    e0 = enabledTracks;
1106    while (e0) {
1107        // process by group of tracks with same output buffer to
1108        // optimize cache use
1109        uint32_t e1 = e0, e2 = e0;
1110        int j = 31 - __builtin_clz(e1);
1111        track_t& t1 = state->tracks[j];
1112        e2 &= ~(1<<j);
1113        while (e2) {
1114            j = 31 - __builtin_clz(e2);
1115            e2 &= ~(1<<j);
1116            track_t& t2 = state->tracks[j];
1117            if (CC_UNLIKELY(t2.mainBuffer != t1.mainBuffer)) {
1118                e1 &= ~(1<<j);
1119            }
1120        }
1121        e0 &= ~(e1);
1122        // this assumes output 16 bits stereo, no resampling
1123        int32_t *out = t1.mainBuffer;
1124        size_t numFrames = 0;
1125        do {
1126            memset(outTemp, 0, sizeof(outTemp));
1127            e2 = e1;
1128            while (e2) {
1129                const int i = 31 - __builtin_clz(e2);
1130                e2 &= ~(1<<i);
1131                track_t& t = state->tracks[i];
1132                size_t outFrames = BLOCKSIZE;
1133                int32_t *aux = NULL;
1134                if (CC_UNLIKELY(t.needs & NEEDS_AUX)) {
1135                    aux = t.auxBuffer + numFrames;
1136                }
1137                while (outFrames) {
1138                    // t.in == NULL can happen if the track was flushed just after having
1139                    // been enabled for mixing.
1140                   if (t.in == NULL) {
1141                        enabledTracks &= ~(1<<i);
1142                        e1 &= ~(1<<i);
1143                        break;
1144                    }
1145                    size_t inFrames = (t.frameCount > outFrames)?outFrames:t.frameCount;
1146                    if (inFrames > 0) {
1147                        t.hook(&t, outTemp + (BLOCKSIZE-outFrames)*MAX_NUM_CHANNELS, inFrames,
1148                                state->resampleTemp, aux);
1149                        t.frameCount -= inFrames;
1150                        outFrames -= inFrames;
1151                        if (CC_UNLIKELY(aux != NULL)) {
1152                            aux += inFrames;
1153                        }
1154                    }
1155                    if (t.frameCount == 0 && outFrames) {
1156                        t.bufferProvider->releaseBuffer(&t.buffer);
1157                        t.buffer.frameCount = (state->frameCount - numFrames) -
1158                                (BLOCKSIZE - outFrames);
1159                        int64_t outputPTS = calculateOutputPTS(
1160                            t, pts, numFrames + (BLOCKSIZE - outFrames));
1161                        t.bufferProvider->getNextBuffer(&t.buffer, outputPTS);
1162                        t.in = t.buffer.raw;
1163                        if (t.in == NULL) {
1164                            enabledTracks &= ~(1<<i);
1165                            e1 &= ~(1<<i);
1166                            break;
1167                        }
1168                        t.frameCount = t.buffer.frameCount;
1169                    }
1170                }
1171            }
1172            ditherAndClamp(out, outTemp, BLOCKSIZE);
1173            out += BLOCKSIZE;
1174            numFrames += BLOCKSIZE;
1175        } while (numFrames < state->frameCount);
1176    }
1177
1178    // release each track's buffer
1179    e0 = enabledTracks;
1180    while (e0) {
1181        const int i = 31 - __builtin_clz(e0);
1182        e0 &= ~(1<<i);
1183        track_t& t = state->tracks[i];
1184        t.bufferProvider->releaseBuffer(&t.buffer);
1185    }
1186}
1187
1188
1189// generic code with resampling
1190void AudioMixer::process__genericResampling(state_t* state, int64_t pts)
1191{
1192    // this const just means that local variable outTemp doesn't change
1193    int32_t* const outTemp = state->outputTemp;
1194    const size_t size = sizeof(int32_t) * MAX_NUM_CHANNELS * state->frameCount;
1195
1196    size_t numFrames = state->frameCount;
1197
1198    uint32_t e0 = state->enabledTracks;
1199    while (e0) {
1200        // process by group of tracks with same output buffer
1201        // to optimize cache use
1202        uint32_t e1 = e0, e2 = e0;
1203        int j = 31 - __builtin_clz(e1);
1204        track_t& t1 = state->tracks[j];
1205        e2 &= ~(1<<j);
1206        while (e2) {
1207            j = 31 - __builtin_clz(e2);
1208            e2 &= ~(1<<j);
1209            track_t& t2 = state->tracks[j];
1210            if (CC_UNLIKELY(t2.mainBuffer != t1.mainBuffer)) {
1211                e1 &= ~(1<<j);
1212            }
1213        }
1214        e0 &= ~(e1);
1215        int32_t *out = t1.mainBuffer;
1216        memset(outTemp, 0, size);
1217        while (e1) {
1218            const int i = 31 - __builtin_clz(e1);
1219            e1 &= ~(1<<i);
1220            track_t& t = state->tracks[i];
1221            int32_t *aux = NULL;
1222            if (CC_UNLIKELY(t.needs & NEEDS_AUX)) {
1223                aux = t.auxBuffer;
1224            }
1225
1226            // this is a little goofy, on the resampling case we don't
1227            // acquire/release the buffers because it's done by
1228            // the resampler.
1229            if (t.needs & NEEDS_RESAMPLE) {
1230                t.resampler->setPTS(pts);
1231                t.hook(&t, outTemp, numFrames, state->resampleTemp, aux);
1232            } else {
1233
1234                size_t outFrames = 0;
1235
1236                while (outFrames < numFrames) {
1237                    t.buffer.frameCount = numFrames - outFrames;
1238                    int64_t outputPTS = calculateOutputPTS(t, pts, outFrames);
1239                    t.bufferProvider->getNextBuffer(&t.buffer, outputPTS);
1240                    t.in = t.buffer.raw;
1241                    // t.in == NULL can happen if the track was flushed just after having
1242                    // been enabled for mixing.
1243                    if (t.in == NULL) break;
1244
1245                    if (CC_UNLIKELY(aux != NULL)) {
1246                        aux += outFrames;
1247                    }
1248                    t.hook(&t, outTemp + outFrames*MAX_NUM_CHANNELS, t.buffer.frameCount,
1249                            state->resampleTemp, aux);
1250                    outFrames += t.buffer.frameCount;
1251                    t.bufferProvider->releaseBuffer(&t.buffer);
1252                }
1253            }
1254        }
1255        ditherAndClamp(out, outTemp, numFrames);
1256    }
1257}
1258
1259// one track, 16 bits stereo without resampling is the most common case
1260void AudioMixer::process__OneTrack16BitsStereoNoResampling(state_t* state,
1261                                                           int64_t pts)
1262{
1263    // This method is only called when state->enabledTracks has exactly
1264    // one bit set.  The asserts below would verify this, but are commented out
1265    // since the whole point of this method is to optimize performance.
1266    //ALOG_ASSERT(0 != state->enabledTracks, "no tracks enabled");
1267    const int i = 31 - __builtin_clz(state->enabledTracks);
1268    //ALOG_ASSERT((1 << i) == state->enabledTracks, "more than 1 track enabled");
1269    const track_t& t = state->tracks[i];
1270
1271    AudioBufferProvider::Buffer& b(t.buffer);
1272
1273    int32_t* out = t.mainBuffer;
1274    size_t numFrames = state->frameCount;
1275
1276    const int16_t vl = t.volume[0];
1277    const int16_t vr = t.volume[1];
1278    const uint32_t vrl = t.volumeRL;
1279    while (numFrames) {
1280        b.frameCount = numFrames;
1281        int64_t outputPTS = calculateOutputPTS(t, pts, out - t.mainBuffer);
1282        t.bufferProvider->getNextBuffer(&b, outputPTS);
1283        const int16_t *in = b.i16;
1284
1285        // in == NULL can happen if the track was flushed just after having
1286        // been enabled for mixing.
1287        if (in == NULL || ((unsigned long)in & 3)) {
1288            memset(out, 0, numFrames*MAX_NUM_CHANNELS*sizeof(int16_t));
1289            ALOGE_IF(((unsigned long)in & 3), "process stereo track: input buffer alignment pb: "
1290                                              "buffer %p track %d, channels %d, needs %08x",
1291                    in, i, t.channelCount, t.needs);
1292            return;
1293        }
1294        size_t outFrames = b.frameCount;
1295
1296        if (CC_UNLIKELY(uint32_t(vl) > UNITY_GAIN || uint32_t(vr) > UNITY_GAIN)) {
1297            // volume is boosted, so we might need to clamp even though
1298            // we process only one track.
1299            do {
1300                uint32_t rl = *reinterpret_cast<const uint32_t *>(in);
1301                in += 2;
1302                int32_t l = mulRL(1, rl, vrl) >> 12;
1303                int32_t r = mulRL(0, rl, vrl) >> 12;
1304                // clamping...
1305                l = clamp16(l);
1306                r = clamp16(r);
1307                *out++ = (r<<16) | (l & 0xFFFF);
1308            } while (--outFrames);
1309        } else {
1310            do {
1311                uint32_t rl = *reinterpret_cast<const uint32_t *>(in);
1312                in += 2;
1313                int32_t l = mulRL(1, rl, vrl) >> 12;
1314                int32_t r = mulRL(0, rl, vrl) >> 12;
1315                *out++ = (r<<16) | (l & 0xFFFF);
1316            } while (--outFrames);
1317        }
1318        numFrames -= b.frameCount;
1319        t.bufferProvider->releaseBuffer(&b);
1320    }
1321}
1322
1323#if 0
1324// 2 tracks is also a common case
1325// NEVER used in current implementation of process__validate()
1326// only use if the 2 tracks have the same output buffer
1327void AudioMixer::process__TwoTracks16BitsStereoNoResampling(state_t* state,
1328                                                            int64_t pts)
1329{
1330    int i;
1331    uint32_t en = state->enabledTracks;
1332
1333    i = 31 - __builtin_clz(en);
1334    const track_t& t0 = state->tracks[i];
1335    AudioBufferProvider::Buffer& b0(t0.buffer);
1336
1337    en &= ~(1<<i);
1338    i = 31 - __builtin_clz(en);
1339    const track_t& t1 = state->tracks[i];
1340    AudioBufferProvider::Buffer& b1(t1.buffer);
1341
1342    const int16_t *in0;
1343    const int16_t vl0 = t0.volume[0];
1344    const int16_t vr0 = t0.volume[1];
1345    size_t frameCount0 = 0;
1346
1347    const int16_t *in1;
1348    const int16_t vl1 = t1.volume[0];
1349    const int16_t vr1 = t1.volume[1];
1350    size_t frameCount1 = 0;
1351
1352    //FIXME: only works if two tracks use same buffer
1353    int32_t* out = t0.mainBuffer;
1354    size_t numFrames = state->frameCount;
1355    const int16_t *buff = NULL;
1356
1357
1358    while (numFrames) {
1359
1360        if (frameCount0 == 0) {
1361            b0.frameCount = numFrames;
1362            int64_t outputPTS = calculateOutputPTS(t0, pts,
1363                                                   out - t0.mainBuffer);
1364            t0.bufferProvider->getNextBuffer(&b0, outputPTS);
1365            if (b0.i16 == NULL) {
1366                if (buff == NULL) {
1367                    buff = new int16_t[MAX_NUM_CHANNELS * state->frameCount];
1368                }
1369                in0 = buff;
1370                b0.frameCount = numFrames;
1371            } else {
1372                in0 = b0.i16;
1373            }
1374            frameCount0 = b0.frameCount;
1375        }
1376        if (frameCount1 == 0) {
1377            b1.frameCount = numFrames;
1378            int64_t outputPTS = calculateOutputPTS(t1, pts,
1379                                                   out - t0.mainBuffer);
1380            t1.bufferProvider->getNextBuffer(&b1, outputPTS);
1381            if (b1.i16 == NULL) {
1382                if (buff == NULL) {
1383                    buff = new int16_t[MAX_NUM_CHANNELS * state->frameCount];
1384                }
1385                in1 = buff;
1386                b1.frameCount = numFrames;
1387            } else {
1388                in1 = b1.i16;
1389            }
1390            frameCount1 = b1.frameCount;
1391        }
1392
1393        size_t outFrames = frameCount0 < frameCount1?frameCount0:frameCount1;
1394
1395        numFrames -= outFrames;
1396        frameCount0 -= outFrames;
1397        frameCount1 -= outFrames;
1398
1399        do {
1400            int32_t l0 = *in0++;
1401            int32_t r0 = *in0++;
1402            l0 = mul(l0, vl0);
1403            r0 = mul(r0, vr0);
1404            int32_t l = *in1++;
1405            int32_t r = *in1++;
1406            l = mulAdd(l, vl1, l0) >> 12;
1407            r = mulAdd(r, vr1, r0) >> 12;
1408            // clamping...
1409            l = clamp16(l);
1410            r = clamp16(r);
1411            *out++ = (r<<16) | (l & 0xFFFF);
1412        } while (--outFrames);
1413
1414        if (frameCount0 == 0) {
1415            t0.bufferProvider->releaseBuffer(&b0);
1416        }
1417        if (frameCount1 == 0) {
1418            t1.bufferProvider->releaseBuffer(&b1);
1419        }
1420    }
1421
1422    delete [] buff;
1423}
1424#endif
1425
1426int64_t AudioMixer::calculateOutputPTS(const track_t& t, int64_t basePTS,
1427                                       int outputFrameIndex)
1428{
1429    if (AudioBufferProvider::kInvalidPTS == basePTS) {
1430        return AudioBufferProvider::kInvalidPTS;
1431    }
1432
1433    return basePTS + ((outputFrameIndex * sLocalTimeFreq) / t.sampleRate);
1434}
1435
1436/*static*/ uint64_t AudioMixer::sLocalTimeFreq;
1437/*static*/ pthread_once_t AudioMixer::sOnceControl = PTHREAD_ONCE_INIT;
1438
1439/*static*/ void AudioMixer::sInitRoutine()
1440{
1441    LocalClock lc;
1442    sLocalTimeFreq = lc.getLocalFreq();
1443
1444    // find multichannel downmix effect if we have to play multichannel content
1445    uint32_t numEffects = 0;
1446    int ret = EffectQueryNumberEffects(&numEffects);
1447    if (ret != 0) {
1448        ALOGE("AudioMixer() error %d querying number of effects", ret);
1449        return;
1450    }
1451    ALOGV("EffectQueryNumberEffects() numEffects=%d", numEffects);
1452
1453    for (uint32_t i = 0 ; i < numEffects ; i++) {
1454        if (EffectQueryEffect(i, &sDwnmFxDesc) == 0) {
1455            ALOGV("effect %d is called %s", i, sDwnmFxDesc.name);
1456            if (memcmp(&sDwnmFxDesc.type, EFFECT_UIID_DOWNMIX, sizeof(effect_uuid_t)) == 0) {
1457                ALOGI("found effect \"%s\" from %s",
1458                        sDwnmFxDesc.name, sDwnmFxDesc.implementor);
1459                sIsMultichannelCapable = true;
1460                break;
1461            }
1462        }
1463    }
1464    ALOGW_IF(!sIsMultichannelCapable, "unable to find downmix effect");
1465}
1466
1467// ----------------------------------------------------------------------------
1468}; // namespace android
1469