1 /*****************************************************************************
2 * audiounit_ios.c: AudioUnit output plugin for iOS
3 *****************************************************************************
4 * Copyright (C) 2012 - 2013 VLC authors and VideoLAN
7 * Authors: Felix Paul Kühne <fkuehne at videolan dot org>
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU Lesser General Public License as published by
11 * the Free Software Foundation; either version 2.1 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Lesser General Public License for more details.
19 * You should have received a copy of the GNU Lesser General Public License
20 * along with this program; if not, write to the Free Software Foundation,
21 * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
22 *****************************************************************************/
30 #import <vlc_common.h>
31 #import <vlc_plugin.h>
34 #import <AudioUnit/AudioUnit.h>
35 #import <CoreAudio/CoreAudioTypes.h>
36 #import <AudioToolbox/AudioToolbox.h>
37 #import <mach/mach_time.h>
39 #import "TPCircularBuffer.h"
42 #pragma mark private declarations
44 #define STREAM_FORMAT_MSG(pre, sfm) \
45 pre "[%f][%4.4s][%u][%u][%u][%u][%u][%u]", \
46 sfm.mSampleRate, (char *)&sfm.mFormatID, \
47 (unsigned int)sfm.mFormatFlags, (unsigned int)sfm.mBytesPerPacket, \
48 (unsigned int)sfm.mFramesPerPacket, (unsigned int)sfm.mBytesPerFrame, \
49 (unsigned int)sfm.mChannelsPerFrame, (unsigned int)sfm.mBitsPerChannel
51 #define AUDIO_BUFFER_SIZE_IN_SECONDS (AOUT_MAX_ADVANCE_TIME / CLOCK_FREQ)
53 /*****************************************************************************
54 * aout_sys_t: private audio output method descriptor
55 *****************************************************************************
56 * This structure is part of the audio output thread descriptor.
57 * It describes the CoreAudio specific properties of an output thread.
58 *****************************************************************************/
61 uint8_t chan_table[AOUT_CHAN_MAX];
63 UInt32 i_numberOfChannels;
64 TPCircularBuffer circular_buffer; /* circular buffer to swap the audio data */
67 AudioComponent au_component; /* The AudioComponent we use */
68 AudioUnit au_unit; /* The AudioUnit we use */
70 int i_rate; /* media sample rate */
71 int i_bytes_per_sample;
72 bool b_got_first_sample;
78 #pragma mark local prototypes & module descriptor
80 static int Open (vlc_object_t *);
81 static void Close (vlc_object_t *);
82 static int Start (audio_output_t *, audio_sample_format_t *);
83 static int StartAnalog (audio_output_t *, audio_sample_format_t *);
84 static void Stop (audio_output_t *);
86 static void Play (audio_output_t *, block_t *);
87 static void Pause (audio_output_t *, bool, mtime_t);
88 static void Flush (audio_output_t *, bool);
89 static int TimeGet (audio_output_t *, mtime_t *);
90 static OSStatus RenderCallback (vlc_object_t *, AudioUnitRenderActionFlags *, const AudioTimeStamp *,
91 UInt32 , UInt32, AudioBufferList *);
93 set_shortname("audiounit_ios")
94 set_description(N_("AudioUnit output for iOS"))
95 set_capability("audio output", 101)
96 set_category(CAT_AUDIO)
97 set_subcategory(SUBCAT_AUDIO_AOUT)
98 set_callbacks(Open, Close)
102 #pragma mark initialization
104 static int Open(vlc_object_t *obj)
106 audio_output_t *aout = (audio_output_t *)obj;
107 aout_sys_t *sys = malloc(sizeof (*sys));
109 if (unlikely(sys == NULL))
112 vlc_mutex_init(&sys->lock);
121 static void Close(vlc_object_t *obj)
123 audio_output_t *aout = (audio_output_t *)obj;
124 aout_sys_t *sys = aout->sys;
126 vlc_mutex_destroy(&sys->lock);
131 static int Start(audio_output_t *p_aout, audio_sample_format_t *restrict fmt)
133 struct aout_sys_t *p_sys = NULL;
136 p_sys->au_component = NULL;
137 p_sys->au_unit = NULL;
138 p_sys->i_bytes_per_sample = 0;
140 aout_FormatPrint(p_aout, "VLC is looking for:", fmt);
142 if (StartAnalog(p_aout, fmt)) {
143 msg_Dbg(p_aout, "analog AudioUnit output successfully opened");
145 p_aout->flush = Flush;
146 p_aout->time_get = TimeGet;
147 p_aout->pause = Pause;
151 /* If we reach this, this aout has failed */
152 msg_Err(p_aout, "opening AudioUnit output failed");
157 * StartAnalog: open and setup a HAL AudioUnit to do PCM audio output
159 static int StartAnalog(audio_output_t *p_aout, audio_sample_format_t *fmt)
161 struct aout_sys_t *p_sys = p_aout->sys;
162 UInt32 i_param_size = 0;
163 AudioComponentDescription desc;
164 AURenderCallbackStruct callback;
167 /* Lets go find our Component */
168 desc.componentType = kAudioUnitType_Output;
169 desc.componentSubType = kAudioUnitSubType_RemoteIO;
170 desc.componentManufacturer = kAudioUnitManufacturer_Apple;
171 desc.componentFlags = 0;
172 desc.componentFlagsMask = 0;
174 p_sys->au_component = AudioComponentFindNext(NULL, &desc);
175 if (p_sys->au_component == NULL) {
176 msg_Warn(p_aout, "we cannot find our audio component");
180 status = AudioComponentInstanceNew(p_sys->au_component, &p_sys->au_unit);
181 if (status != noErr) {
182 msg_Warn(p_aout, "we cannot open our audio component (%li)", status);
187 status = AudioUnitSetProperty(p_sys->au_unit,
188 kAudioOutputUnitProperty_EnableIO,
189 kAudioUnitScope_Output,
194 msg_Warn(p_aout, "failed to set IO mode (%li)", status);
196 /* Get the current format */
197 AudioStreamBasicDescription streamDescription;
198 streamDescription.mSampleRate = fmt->i_rate;
199 fmt->i_format = VLC_CODEC_FL32;
200 fmt->i_physical_channels = AOUT_CHANS_STEREO;
201 streamDescription.mFormatID = kAudioFormatLinearPCM;
202 streamDescription.mFormatFlags = kAudioFormatFlagsNativeFloatPacked; // FL32
203 streamDescription.mChannelsPerFrame = aout_FormatNbChannels(fmt);
204 streamDescription.mFramesPerPacket = 1;
205 streamDescription.mBitsPerChannel = 32;
206 streamDescription.mBytesPerFrame = streamDescription.mBitsPerChannel * streamDescription.mChannelsPerFrame / 8;
207 streamDescription.mBytesPerPacket = streamDescription.mBytesPerFrame * streamDescription.mFramesPerPacket;
208 i_param_size = sizeof(streamDescription);
209 p_sys->i_rate = fmt->i_rate;
211 /* Set the desired format */
212 i_param_size = sizeof(AudioStreamBasicDescription);
213 status = AudioUnitSetProperty(p_sys->au_unit,
214 kAudioUnitProperty_StreamFormat,
215 kAudioUnitScope_Input,
219 if (status != noErr) {
220 msg_Err(p_aout, "failed to set stream format (%li)", status);
223 msg_Dbg(p_aout, STREAM_FORMAT_MSG("we set the AU format: " , streamDescription));
225 /* Retrieve actual format */
226 status = AudioUnitGetProperty(p_sys->au_unit,
227 kAudioUnitProperty_StreamFormat,
228 kAudioUnitScope_Input,
233 msg_Warn(p_aout, "failed to verify stream format (%li)", status);
234 msg_Dbg(p_aout, STREAM_FORMAT_MSG("the actual set AU format is " , streamDescription));
236 /* Do the last VLC aout setups */
237 aout_FormatPrepare(fmt);
239 /* set the IOproc callback */
240 callback.inputProc = (AURenderCallback) RenderCallback;
241 callback.inputProcRefCon = p_aout;
243 status = AudioUnitSetProperty(p_sys->au_unit,
244 kAudioUnitProperty_SetRenderCallback,
245 kAudioUnitScope_Input,
246 0, &callback, sizeof(callback));
247 if (status != noErr) {
248 msg_Err(p_aout, "render callback setup failed (%li)", status);
253 status = AudioUnitInitialize(p_sys->au_unit);
254 if (status != noErr) {
255 msg_Err(p_aout, "failed to init AudioUnit (%li)", status);
259 /* start audio session so playback continues if mute switch is on */
260 AudioSessionInitialize (NULL,
261 kCFRunLoopCommonModes,
265 /* Set audio session to mediaplayback */
266 UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
267 AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory),&sessionCategory);
268 AudioSessionSetActive(true);
270 /* setup circular buffer */
271 TPCircularBufferInit(&p_sys->circular_buffer, AUDIO_BUFFER_SIZE_IN_SECONDS * fmt->i_rate * fmt->i_bytes_per_frame);
273 p_sys->b_got_first_sample = false;
278 static void Stop(audio_output_t *p_aout)
280 struct aout_sys_t *p_sys = p_aout->sys;
283 AudioSessionSetActive(false);
285 if (p_sys->au_unit) {
286 status = AudioOutputUnitStop(p_sys->au_unit);
288 msg_Warn(p_aout, "failed to stop AudioUnit (%li)", status);
290 status = AudioComponentInstanceDispose(p_sys->au_unit);
292 msg_Warn(p_aout, "failed to dispose Audio Component instance (%li)", status);
294 p_sys->i_bytes_per_sample = 0;
296 /* clean-up circular buffer */
297 TPCircularBufferCleanup(&p_sys->circular_buffer);
301 #pragma mark actual playback
303 static void Play (audio_output_t * p_aout, block_t * p_block)
305 struct aout_sys_t *p_sys = p_aout->sys;
307 if (p_block->i_nb_samples > 0) {
308 if (!p_sys->b_got_first_sample) {
310 OSStatus status = AudioOutputUnitStart(p_sys->au_unit);
311 msg_Dbg(p_aout, "audio output unit started: %li", status);
312 p_sys->b_got_first_sample = true;
315 /* move data to buffer */
316 if (unlikely(!TPCircularBufferProduceBytes(&p_sys->circular_buffer, p_block->p_buffer, p_block->i_buffer)))
317 msg_Warn(p_aout, "Audio buffer was dropped");
319 if (!p_sys->i_bytes_per_sample)
320 p_sys->i_bytes_per_sample = p_block->i_buffer / p_block->i_nb_samples;
323 block_Release(p_block);
326 static void Pause (audio_output_t *p_aout, bool pause, mtime_t date)
328 struct aout_sys_t * p_sys = p_aout->sys;
332 AudioOutputUnitStop(p_sys->au_unit);
333 AudioSessionSetActive(false);
335 AudioOutputUnitStart(p_sys->au_unit);
336 AudioSessionSetActive(true);
340 static void Flush(audio_output_t *p_aout, bool wait)
342 struct aout_sys_t * p_sys = p_aout->sys;
345 p_sys->b_got_first_sample = false;
347 /* flush circular buffer */
348 AudioOutputUnitStop(p_aout->sys->au_unit);
349 TPCircularBufferClear(&p_aout->sys->circular_buffer);
352 static int TimeGet(audio_output_t *p_aout, mtime_t *delay)
354 struct aout_sys_t * p_sys = p_aout->sys;
356 if (!p_sys->i_bytes_per_sample)
359 int32_t availableBytes;
360 TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
362 *delay = (availableBytes / p_sys->i_bytes_per_sample) * CLOCK_FREQ / p_sys->i_rate;
367 /*****************************************************************************
368 * RenderCallback: This function is called everytime the AudioUnit wants
369 * us to provide some more audio data.
370 * Don't print anything during normal playback, calling blocking function from
371 * this callback is not allowed.
372 *****************************************************************************/
373 static OSStatus RenderCallback(vlc_object_t *p_obj,
374 AudioUnitRenderActionFlags *ioActionFlags,
375 const AudioTimeStamp *inTimeStamp,
377 UInt32 inNumberFrames,
378 AudioBufferList *ioData) {
379 VLC_UNUSED(ioActionFlags);
380 VLC_UNUSED(inTimeStamp);
381 VLC_UNUSED(inBusNumber);
383 audio_output_t * p_aout = (audio_output_t *)p_obj;
384 struct aout_sys_t * p_sys = p_aout->sys;
386 int bytesToCopy = ioData->mBuffers[0].mDataByteSize;
387 Float32 *targetBuffer = (Float32*)ioData->mBuffers[0].mData;
389 /* Pull audio from buffer */
390 int32_t availableBytes = 0;
391 Float32 *buffer = TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
393 /* check if we have enough data */
394 if (!availableBytes) {
395 /* return an empty buffer so silence is played until we have data */
396 for (UInt32 j = 0; j < inNumberFrames; j++)
397 targetBuffer[j] = 0.;
399 memcpy(targetBuffer, buffer, __MIN(bytesToCopy, availableBytes));
400 TPCircularBufferConsume(&p_sys->circular_buffer, __MIN(bytesToCopy, availableBytes));
401 VLC_UNUSED(inNumberFrames);