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;
69 bool b_got_first_sample;
73 #pragma mark local prototypes & module descriptor
75 static int Open (vlc_object_t *);
76 static void Close (vlc_object_t *);
77 static int Start (audio_output_t *, audio_sample_format_t *);
78 static int StartAnalog (audio_output_t *, audio_sample_format_t *);
79 static void Stop (audio_output_t *);
81 static void Play (audio_output_t *, block_t *);
82 static void Pause (audio_output_t *, bool, mtime_t);
83 static void Flush (audio_output_t *, bool);
84 static int TimeGet (audio_output_t *, mtime_t *);
85 static OSStatus RenderCallback (vlc_object_t *, AudioUnitRenderActionFlags *, const AudioTimeStamp *,
86 UInt32 , UInt32, AudioBufferList *);
88 set_shortname("audiounit_ios")
89 set_description(N_("AudioUnit output for iOS"))
90 set_capability("audio output", 101)
91 set_category(CAT_AUDIO)
92 set_subcategory(SUBCAT_AUDIO_AOUT)
93 set_callbacks(Open, Close)
97 #pragma mark initialization
99 static int Open(vlc_object_t *obj)
101 audio_output_t *aout = (audio_output_t *)obj;
102 aout_sys_t *sys = malloc(sizeof (*sys));
104 if (unlikely(sys == NULL))
114 static void Close(vlc_object_t *obj)
116 audio_output_t *aout = (audio_output_t *)obj;
117 aout_sys_t *sys = aout->sys;
122 static int Start(audio_output_t *p_aout, audio_sample_format_t *restrict fmt)
124 struct aout_sys_t *p_sys = NULL;
127 p_sys->au_component = NULL;
128 p_sys->au_unit = NULL;
129 p_sys->i_bytes_per_sample = 0;
131 aout_FormatPrint(p_aout, "VLC is looking for:", fmt);
133 if (StartAnalog(p_aout, fmt)) {
134 msg_Dbg(p_aout, "analog AudioUnit output successfully opened");
136 p_aout->flush = Flush;
137 p_aout->time_get = TimeGet;
138 p_aout->pause = Pause;
142 /* If we reach this, this aout has failed */
143 msg_Err(p_aout, "opening AudioUnit output failed");
148 * StartAnalog: open and setup a HAL AudioUnit to do PCM audio output
150 static int StartAnalog(audio_output_t *p_aout, audio_sample_format_t *fmt)
152 struct aout_sys_t *p_sys = p_aout->sys;
153 UInt32 i_param_size = 0;
154 AudioComponentDescription desc;
155 AURenderCallbackStruct callback;
158 /* Lets go find our Component */
159 desc.componentType = kAudioUnitType_Output;
160 desc.componentSubType = kAudioUnitSubType_RemoteIO;
161 desc.componentManufacturer = kAudioUnitManufacturer_Apple;
162 desc.componentFlags = 0;
163 desc.componentFlagsMask = 0;
165 p_sys->au_component = AudioComponentFindNext(NULL, &desc);
166 if (p_sys->au_component == NULL) {
167 msg_Warn(p_aout, "we cannot find our audio component");
171 status = AudioComponentInstanceNew(p_sys->au_component, &p_sys->au_unit);
172 if (status != noErr) {
173 msg_Warn(p_aout, "we cannot open our audio component (%li)", status);
178 status = AudioUnitSetProperty(p_sys->au_unit,
179 kAudioOutputUnitProperty_EnableIO,
180 kAudioUnitScope_Output,
185 msg_Warn(p_aout, "failed to set IO mode (%li)", status);
187 /* Get the current format */
188 AudioStreamBasicDescription streamDescription;
189 streamDescription.mSampleRate = fmt->i_rate;
190 fmt->i_format = VLC_CODEC_FL32;
191 fmt->i_physical_channels = AOUT_CHANS_STEREO;
192 streamDescription.mFormatID = kAudioFormatLinearPCM;
193 streamDescription.mFormatFlags = kAudioFormatFlagsNativeFloatPacked; // FL32
194 streamDescription.mChannelsPerFrame = aout_FormatNbChannels(fmt);
195 streamDescription.mFramesPerPacket = 1;
196 streamDescription.mBitsPerChannel = 32;
197 streamDescription.mBytesPerFrame = streamDescription.mBitsPerChannel * streamDescription.mChannelsPerFrame / 8;
198 streamDescription.mBytesPerPacket = streamDescription.mBytesPerFrame * streamDescription.mFramesPerPacket;
199 i_param_size = sizeof(streamDescription);
200 p_sys->i_rate = fmt->i_rate;
202 /* Set the desired format */
203 i_param_size = sizeof(AudioStreamBasicDescription);
204 status = AudioUnitSetProperty(p_sys->au_unit,
205 kAudioUnitProperty_StreamFormat,
206 kAudioUnitScope_Input,
210 if (status != noErr) {
211 msg_Err(p_aout, "failed to set stream format (%li)", status);
214 msg_Dbg(p_aout, STREAM_FORMAT_MSG("we set the AU format: " , streamDescription));
216 /* Retrieve actual format */
217 status = AudioUnitGetProperty(p_sys->au_unit,
218 kAudioUnitProperty_StreamFormat,
219 kAudioUnitScope_Input,
224 msg_Warn(p_aout, "failed to verify stream format (%li)", status);
225 msg_Dbg(p_aout, STREAM_FORMAT_MSG("the actual set AU format is " , streamDescription));
227 /* Do the last VLC aout setups */
228 aout_FormatPrepare(fmt);
230 /* set the IOproc callback */
231 callback.inputProc = (AURenderCallback) RenderCallback;
232 callback.inputProcRefCon = p_aout;
234 status = AudioUnitSetProperty(p_sys->au_unit,
235 kAudioUnitProperty_SetRenderCallback,
236 kAudioUnitScope_Input,
237 0, &callback, sizeof(callback));
238 if (status != noErr) {
239 msg_Err(p_aout, "render callback setup failed (%li)", status);
244 status = AudioUnitInitialize(p_sys->au_unit);
245 if (status != noErr) {
246 msg_Err(p_aout, "failed to init AudioUnit (%li)", status);
250 /* start audio session so playback continues if mute switch is on */
251 AudioSessionInitialize (NULL,
252 kCFRunLoopCommonModes,
256 /* Set audio session to mediaplayback */
257 UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
258 AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory),&sessionCategory);
259 AudioSessionSetActive(true);
261 /* setup circular buffer */
262 TPCircularBufferInit(&p_sys->circular_buffer, AUDIO_BUFFER_SIZE_IN_SECONDS * fmt->i_rate * fmt->i_bytes_per_frame);
264 p_sys->b_got_first_sample = false;
269 static void Stop(audio_output_t *p_aout)
271 struct aout_sys_t *p_sys = p_aout->sys;
274 AudioSessionSetActive(false);
276 if (p_sys->au_unit) {
277 status = AudioOutputUnitStop(p_sys->au_unit);
279 msg_Warn(p_aout, "failed to stop AudioUnit (%li)", status);
281 status = AudioComponentInstanceDispose(p_sys->au_unit);
283 msg_Warn(p_aout, "failed to dispose Audio Component instance (%li)", status);
285 p_sys->i_bytes_per_sample = 0;
287 /* clean-up circular buffer */
288 TPCircularBufferCleanup(&p_sys->circular_buffer);
292 #pragma mark actual playback
294 static void Play (audio_output_t * p_aout, block_t * p_block)
296 struct aout_sys_t *p_sys = p_aout->sys;
298 if (p_block->i_nb_samples > 0) {
299 if (!p_sys->b_got_first_sample) {
301 OSStatus status = AudioOutputUnitStart(p_sys->au_unit);
302 msg_Dbg(p_aout, "audio output unit started: %li", status);
303 p_sys->b_got_first_sample = true;
306 /* move data to buffer */
307 if (unlikely(!TPCircularBufferProduceBytes(&p_sys->circular_buffer, p_block->p_buffer, p_block->i_buffer)))
308 msg_Warn(p_aout, "Audio buffer was dropped");
310 if (!p_sys->i_bytes_per_sample)
311 p_sys->i_bytes_per_sample = p_block->i_buffer / p_block->i_nb_samples;
314 block_Release(p_block);
317 static void Pause (audio_output_t *p_aout, bool pause, mtime_t date)
319 struct aout_sys_t * p_sys = p_aout->sys;
323 AudioOutputUnitStop(p_sys->au_unit);
324 AudioSessionSetActive(false);
326 AudioOutputUnitStart(p_sys->au_unit);
327 AudioSessionSetActive(true);
331 static void Flush(audio_output_t *p_aout, bool wait)
333 struct aout_sys_t * p_sys = p_aout->sys;
336 p_sys->b_got_first_sample = false;
338 /* flush circular buffer */
339 AudioOutputUnitStop(p_aout->sys->au_unit);
340 TPCircularBufferClear(&p_aout->sys->circular_buffer);
343 static int TimeGet(audio_output_t *p_aout, mtime_t *delay)
345 struct aout_sys_t * p_sys = p_aout->sys;
347 if (!p_sys->i_bytes_per_sample)
350 int32_t availableBytes;
351 TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
353 *delay = (availableBytes / p_sys->i_bytes_per_sample) * CLOCK_FREQ / p_sys->i_rate;
358 /*****************************************************************************
359 * RenderCallback: This function is called everytime the AudioUnit wants
360 * us to provide some more audio data.
361 * Don't print anything during normal playback, calling blocking function from
362 * this callback is not allowed.
363 *****************************************************************************/
364 static OSStatus RenderCallback(vlc_object_t *p_obj,
365 AudioUnitRenderActionFlags *ioActionFlags,
366 const AudioTimeStamp *inTimeStamp,
368 UInt32 inNumberFrames,
369 AudioBufferList *ioData) {
370 VLC_UNUSED(ioActionFlags);
371 VLC_UNUSED(inTimeStamp);
372 VLC_UNUSED(inBusNumber);
374 audio_output_t * p_aout = (audio_output_t *)p_obj;
375 struct aout_sys_t * p_sys = p_aout->sys;
377 int bytesToCopy = ioData->mBuffers[0].mDataByteSize;
378 Float32 *targetBuffer = (Float32*)ioData->mBuffers[0].mData;
380 /* Pull audio from buffer */
381 int32_t availableBytes = 0;
382 Float32 *buffer = TPCircularBufferTail(&p_sys->circular_buffer, &availableBytes);
384 /* check if we have enough data */
385 if (!availableBytes) {
386 /* bail out and restart unit the next time we receive some data */
387 Flush(p_aout, false);
389 memcpy(targetBuffer, buffer, __MIN(bytesToCopy, availableBytes));
390 TPCircularBufferConsume(&p_sys->circular_buffer, __MIN(bytesToCopy, availableBytes));
391 VLC_UNUSED(inNumberFrames);