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 TPCircularBuffer circular_buffer; /* circular buffer to swap the audio data */
64 AudioComponent au_component; /* The AudioComponent we use */
65 AudioUnit au_unit; /* The AudioUnit we use */
67 int i_rate; /* media sample rate */
68 int i_bytes_per_sample;
77 #pragma mark local prototypes & module descriptor
79 static int Open (vlc_object_t *);
80 static void Close (vlc_object_t *);
81 static int Start (audio_output_t *, audio_sample_format_t *);
82 static int StartAnalog (audio_output_t *, audio_sample_format_t *);
83 static void Stop (audio_output_t *);
85 static void Play (audio_output_t *, block_t *);
86 static void Pause (audio_output_t *, bool, mtime_t);
87 static void Flush (audio_output_t *, bool);
88 static int TimeGet (audio_output_t *, mtime_t *);
89 static OSStatus RenderCallback (vlc_object_t *, AudioUnitRenderActionFlags *, const AudioTimeStamp *,
90 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);
113 vlc_cond_init(&sys->cond);
114 sys->b_paused = false;
123 static void Close(vlc_object_t *obj)
125 audio_output_t *aout = (audio_output_t *)obj;
126 aout_sys_t *sys = aout->sys;
128 vlc_mutex_destroy(&sys->lock);
129 vlc_cond_destroy(&sys->cond);
134 static int Start(audio_output_t *p_aout, audio_sample_format_t *restrict fmt)
136 struct aout_sys_t *p_sys = NULL;
139 p_sys->au_component = NULL;
140 p_sys->au_unit = NULL;
141 p_sys->i_bytes_per_sample = 0;
143 aout_FormatPrint(p_aout, "VLC is looking for:", fmt);
145 if (StartAnalog(p_aout, fmt)) {
146 msg_Dbg(p_aout, "analog AudioUnit output successfully opened");
148 p_aout->flush = Flush;
149 p_aout->time_get = TimeGet;
150 p_aout->pause = Pause;
154 /* If we reach this, this aout has failed */
155 msg_Err(p_aout, "opening AudioUnit output failed");
160 * StartAnalog: open and setup a HAL AudioUnit to do PCM audio output
162 static int StartAnalog(audio_output_t *p_aout, audio_sample_format_t *fmt)
164 struct aout_sys_t *p_sys = p_aout->sys;
165 UInt32 i_param_size = 0;
166 AudioComponentDescription desc;
167 AURenderCallbackStruct callback;
170 /* Lets go find our Component */
171 desc.componentType = kAudioUnitType_Output;
172 desc.componentSubType = kAudioUnitSubType_RemoteIO;
173 desc.componentManufacturer = kAudioUnitManufacturer_Apple;
174 desc.componentFlags = 0;
175 desc.componentFlagsMask = 0;
177 p_sys->au_component = AudioComponentFindNext(NULL, &desc);
178 if (p_sys->au_component == NULL) {
179 msg_Warn(p_aout, "we cannot find our audio component");
183 status = AudioComponentInstanceNew(p_sys->au_component, &p_sys->au_unit);
184 if (status != noErr) {
185 msg_Warn(p_aout, "we cannot open our audio component (%i)", (int)status);
190 status = AudioUnitSetProperty(p_sys->au_unit,
191 kAudioOutputUnitProperty_EnableIO,
192 kAudioUnitScope_Output,
197 msg_Warn(p_aout, "failed to set IO mode (%i)", (int)status);
199 /* Get the current format */
200 AudioStreamBasicDescription streamDescription;
201 streamDescription.mSampleRate = fmt->i_rate;
202 fmt->i_format = VLC_CODEC_FL32;
203 fmt->i_physical_channels = fmt->i_original_channels = AOUT_CHANS_STEREO;
204 streamDescription.mFormatID = kAudioFormatLinearPCM;
205 streamDescription.mFormatFlags = kAudioFormatFlagsNativeFloatPacked; // FL32
206 streamDescription.mChannelsPerFrame = aout_FormatNbChannels(fmt);
207 streamDescription.mFramesPerPacket = 1;
208 streamDescription.mBitsPerChannel = 32;
209 streamDescription.mBytesPerFrame = streamDescription.mBitsPerChannel * streamDescription.mChannelsPerFrame / 8;
210 streamDescription.mBytesPerPacket = streamDescription.mBytesPerFrame * streamDescription.mFramesPerPacket;
211 i_param_size = sizeof(streamDescription);
212 p_sys->i_rate = fmt->i_rate;
214 /* Set the desired format */
215 i_param_size = sizeof(AudioStreamBasicDescription);
216 status = AudioUnitSetProperty(p_sys->au_unit,
217 kAudioUnitProperty_StreamFormat,
218 kAudioUnitScope_Input,
222 if (status != noErr) {
223 msg_Err(p_aout, "failed to set stream format (%i)", (int)status);
226 msg_Dbg(p_aout, STREAM_FORMAT_MSG("we set the AU format: " , streamDescription));
228 /* Retrieve actual format */
229 status = AudioUnitGetProperty(p_sys->au_unit,
230 kAudioUnitProperty_StreamFormat,
231 kAudioUnitScope_Input,
236 msg_Warn(p_aout, "failed to verify stream format (%i)", (int)status);
237 msg_Dbg(p_aout, STREAM_FORMAT_MSG("the actual set AU format is " , streamDescription));
239 /* Do the last VLC aout setups */
240 aout_FormatPrepare(fmt);
242 /* set the IOproc callback */
243 callback.inputProc = (AURenderCallback) RenderCallback;
244 callback.inputProcRefCon = p_aout;
246 status = AudioUnitSetProperty(p_sys->au_unit,
247 kAudioUnitProperty_SetRenderCallback,
248 kAudioUnitScope_Input,
249 0, &callback, sizeof(callback));
250 if (status != noErr) {
251 msg_Err(p_aout, "render callback setup failed (%i)", (int)status);
256 status = AudioUnitInitialize(p_sys->au_unit);
257 if (status != noErr) {
258 msg_Err(p_aout, "failed to init AudioUnit (%i)", (int)status);
262 /* setup circular buffer */
263 TPCircularBufferInit(&p_sys->circular_buffer, AUDIO_BUFFER_SIZE_IN_SECONDS * fmt->i_rate * fmt->i_bytes_per_frame);
265 /* start audio session so playback continues if mute switch is on */
266 AudioSessionInitialize (NULL,
267 kCFRunLoopCommonModes,
271 /* Set audio session to mediaplayback */
272 UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
273 AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory),&sessionCategory);
274 AudioSessionSetActive(true);
277 status = AudioOutputUnitStart(p_sys->au_unit);
278 msg_Dbg(p_aout, "audio output unit started: %i", (int)status);
283 static void Stop(audio_output_t *p_aout)
285 struct aout_sys_t *p_sys = p_aout->sys;
288 AudioSessionSetActive(false);
290 if (p_sys->au_unit) {
291 status = AudioOutputUnitStop(p_sys->au_unit);
293 msg_Warn(p_aout, "failed to stop AudioUnit (%i)", (int)status);
295 status = AudioComponentInstanceDispose(p_sys->au_unit);
297 msg_Warn(p_aout, "failed to dispose Audio Component instance (%i)", (int)status);
299 p_sys->i_bytes_per_sample = 0;
301 /* clean-up circular buffer */
302 TPCircularBufferCleanup(&p_sys->circular_buffer);
306 #pragma mark actual playback
308 static void Play (audio_output_t * p_aout, block_t * p_block)
310 struct aout_sys_t *p_sys = p_aout->sys;
312 if (p_block->i_nb_samples > 0) {
313 /* move data to buffer */
314 if (unlikely(!TPCircularBufferProduceBytes(&p_sys->circular_buffer, p_block->p_buffer, p_block->i_buffer)))
315 msg_Warn(p_aout, "Audio buffer was dropped");
317 if (!p_sys->i_bytes_per_sample)
318 p_sys->i_bytes_per_sample = p_block->i_buffer / p_block->i_nb_samples;
321 block_Release(p_block);
324 static void Pause (audio_output_t *p_aout, bool pause, mtime_t date)
326 struct aout_sys_t * p_sys = p_aout->sys;
329 vlc_mutex_lock(&p_sys->lock);
330 p_sys->b_paused = pause;
331 vlc_mutex_unlock(&p_sys->lock);
333 /* we need to start / stop the audio unit here because otherwise
334 * the OS won't believe us that we stopped the audio output
335 * so in case of an interruption, our unit would be permanently
337 * in case of multi-tasking, the multi-tasking view would still
338 * show a playing state despite we are paused, same for lock screen */
340 AudioOutputUnitStop(p_sys->au_unit);
341 AudioSessionSetActive(false);
343 AudioOutputUnitStart(p_sys->au_unit);
344 UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
345 AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory),&sessionCategory);
346 AudioSessionSetActive(true);
350 static void Flush(audio_output_t *p_aout, bool wait)
352 struct aout_sys_t *p_sys = p_aout->sys;
354 int32_t availableBytes;
355 vlc_mutex_lock(&p_sys->lock);
356 TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
359 while (availableBytes > 0) {
360 vlc_cond_wait(&p_sys->cond, &p_sys->lock);
361 TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
364 /* flush circular buffer if data is left */
365 if (availableBytes > 0)
366 TPCircularBufferClear(&p_aout->sys->circular_buffer);
369 vlc_mutex_unlock(&p_sys->lock);
372 static int TimeGet(audio_output_t *p_aout, mtime_t *delay)
374 struct aout_sys_t * p_sys = p_aout->sys;
376 if (!p_sys->i_bytes_per_sample)
379 int32_t availableBytes;
380 TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
382 *delay = (availableBytes / p_sys->i_bytes_per_sample) * CLOCK_FREQ / p_sys->i_rate;
387 /*****************************************************************************
388 * RenderCallback: This function is called everytime the AudioUnit wants
389 * us to provide some more audio data.
390 * Don't print anything during normal playback, calling blocking function from
391 * this callback is not allowed.
392 *****************************************************************************/
393 static OSStatus RenderCallback(vlc_object_t *p_obj,
394 AudioUnitRenderActionFlags *ioActionFlags,
395 const AudioTimeStamp *inTimeStamp,
397 UInt32 inNumberFrames,
398 AudioBufferList *ioData) {
399 VLC_UNUSED(ioActionFlags);
400 VLC_UNUSED(inTimeStamp);
401 VLC_UNUSED(inBusNumber);
402 VLC_UNUSED(inNumberFrames);
404 audio_output_t * p_aout = (audio_output_t *)p_obj;
405 struct aout_sys_t * p_sys = p_aout->sys;
407 int bytesRequested = ioData->mBuffers[0].mDataByteSize;
408 Float32 *targetBuffer = (Float32*)ioData->mBuffers[0].mData;
410 vlc_mutex_lock(&p_sys->lock);
411 /* Pull audio from buffer */
412 int32_t availableBytes;
413 Float32 *buffer = TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
415 /* check if we have enough data */
416 if (!availableBytes || p_sys->b_paused) {
417 /* return an empty buffer so silence is played until we have data */
418 memset(targetBuffer, 0, ioData->mBuffers[0].mDataByteSize);
420 int32_t bytesToCopy = __MIN(bytesRequested, availableBytes);
422 if (likely(bytesToCopy > 0)) {
423 memcpy(targetBuffer, buffer, bytesToCopy);
424 TPCircularBufferConsume(&p_sys->circular_buffer, bytesToCopy);
425 ioData->mBuffers[0].mDataByteSize = bytesToCopy;
429 vlc_cond_signal(&p_sys->cond);
430 vlc_mutex_unlock(&p_sys->lock);