1 files changed, 201 insertions, 0 deletions
diff --git a/audio/out/ao_audiounit.m b/audio/out/ao_audiounit.m
new file mode 100644
index 0000000000..7411a1a1dd
--- /dev/null
+++ b/audio/out/ao_audiounit.m
@@ -0,0 +1,201 @@
+/*
+ * This file is part of mpv.
+ *
+ * mpv is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * mpv is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with mpv.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+#include "ao.h"
+#include "internal.h"
+#include "audio/format.h"
+#include "osdep/timer.h"
+#include "options/m_option.h"
+#include "misc/ring.h"
+#include "common/msg.h"
+#include "ao_coreaudio_utils.h"
+#include "ao_coreaudio_chmap.h"
+
+#import <AudioUnit/AudioUnit.h>
+#import <CoreAudio/CoreAudioTypes.h>
+#import <AudioToolbox/AudioToolbox.h>
+#import <AVFoundation/AVFoundation.h>
+#import <mach/mach_time.h>
+
+struct priv {
+    AudioUnit audio_unit;
+    double device_latency;
+};
+
+static OSStatus render_cb_lpcm(void *ctx, AudioUnitRenderActionFlags *aflags,
+                              const AudioTimeStamp *ts, UInt32 bus,
+                              UInt32 frames, AudioBufferList *buffer_list)
+{
+    struct ao *ao = ctx;
+    struct priv *p = ao->priv;
+    void *planes[MP_NUM_CHANNELS] = {0};
+
+    for (int n = 0; n < ao->num_planes; n++)
+        planes[n] = buffer_list->mBuffers[n].mData;
+
+    int64_t end = mp_time_us();
+    end += ca_frames_to_us(ao, frames);
+    end += p->device_latency * 1e6;
+    ao_read_data(ao, planes, frames, end);
+    return noErr;
+}
+
+static bool init_audiounit(struct ao *ao)
+{
+    AudioStreamBasicDescription asbd;
+    OSStatus err;
+    uint32_t size;
+    struct priv *p = ao->priv;
+    AVAudioSession *instance = AVAudioSession.sharedInstance;
+    AVAudioSessionPortDescription *port = nil;
+    NSInteger maxChannels = instance.maximumOutputNumberOfChannels;
+    NSInteger prefChannels = MIN(maxChannels, ao->channels.num);
+
+    [instance setCategory:AVAudioSessionCategoryPlayback error:nil];
+    [instance setMode:AVAudioSessionModeMoviePlayback error:nil];
+    [instance setActive:YES error:nil];
+    [instance setPreferredOutputNumberOfChannels:prefChannels error:nil];
+
+    AudioComponentDescription desc = (AudioComponentDescription) {
+        .componentType         = kAudioUnitType_Output,
+        .componentSubType      = kAudioUnitSubType_RemoteIO,
+        .componentManufacturer = kAudioUnitManufacturer_Apple,
+        .componentFlags        = 0,
+        .componentFlagsMask    = 0,
+    };
+
+    AudioComponent comp = AudioComponentFindNext(NULL, &desc);
+    if (comp == NULL) {
+        MP_ERR(ao, "unable to find audio component\n");
+        goto coreaudio_error;
+    }
+
+    err = AudioComponentInstanceNew(comp, &(p->audio_unit));
+    CHECK_CA_ERROR("unable to open audio component");
+
+    err = AudioUnitInitialize(p->audio_unit);
+    CHECK_CA_ERROR_L(coreaudio_error_component,
+                     "unable to initialize audio unit");
+
+    if (af_fmt_is_spdif(ao->format) || instance.outputNumberOfChannels <= 2) {
+        ao->channels = (struct mp_chmap)MP_CHMAP_INIT_STEREO;
+    } else {
+        port = instance.currentRoute.outputs.firstObject;
+        if (port.channels.count == 2 &&
+            port.channels[0].channelLabel == kAudioChannelLabel_Unknown) {
+            // Special case when using an HDMI adapter. The iOS device will
+            // perform SPDIF conversion for us, so send all available channels
+            // using the AC3 mapping.
+            ao->channels = (struct mp_chmap)MP_CHMAP6(FL, FC, FR, SL, SR, LFE);
+        } else {
+            ao->channels.num = (uint8_t)port.channels.count;
+            for (AVAudioSessionChannelDescription *ch in port.channels) {
+              ao->channels.speaker[ch.channelNumber - 1] =
+                  ca_label_to_mp_speaker_id(ch.channelLabel);
+            }
+        }
+    }
+
+    ca_fill_asbd(ao, &asbd);
+    size = sizeof(AudioStreamBasicDescription);
+    err = AudioUnitSetProperty(p->audio_unit,
+                               kAudioUnitProperty_StreamFormat,
+                               kAudioUnitScope_Input, 0, &asbd, size);
+
+    CHECK_CA_ERROR_L(coreaudio_error_audiounit,
+                     "unable to set the input format on the audio unit");
+
+    AURenderCallbackStruct render_cb = (AURenderCallbackStruct) {
+        .inputProc       = render_cb_lpcm,
+        .inputProcRefCon = ao,
+    };
+
+    err = AudioUnitSetProperty(p->audio_unit,
+                               kAudioUnitProperty_SetRenderCallback,
+                               kAudioUnitScope_Input, 0, &render_cb,
+                               sizeof(AURenderCallbackStruct));
+
+    CHECK_CA_ERROR_L(coreaudio_error_audiounit,
+                     "unable to set render callback on audio unit");
+
+    return true;
+
+coreaudio_error_audiounit:
+    AudioUnitUninitialize(p->audio_unit);
+coreaudio_error_component:
+    AudioComponentInstanceDispose(p->audio_unit);
+coreaudio_error:
+    return false;
+}
+
+static void stop(struct ao *ao)
+{
+    struct priv *p = ao->priv;
+    OSStatus err = AudioOutputUnitStop(p->audio_unit);
+    CHECK_CA_WARN("can't stop audio unit");
+}
+
+static void start(struct ao *ao)
+{
+    struct priv *p = ao->priv;
+    AVAudioSession *instance = AVAudioSession.sharedInstance;
+
+    p->device_latency = [instance outputLatency];
+
+    OSStatus err = AudioOutputUnitStart(p->audio_unit);
+    CHECK_CA_WARN("can't start audio unit");
+}
+
+static void uninit(struct ao *ao)
+{
+    struct priv *p = ao->priv;
+    AudioOutputUnitStop(p->audio_unit);
+    AudioUnitUninitialize(p->audio_unit);
+    AudioComponentInstanceDispose(p->audio_unit);
+
+    [AVAudioSession.sharedInstance
+        setActive:NO
+        withOptions:AVAudioSessionSetActiveOptionNotifyOthersOnDeactivation
+        error:nil];
+}
+
+static int init(struct ao *ao)
+{
+    if (!init_audiounit(ao))
+        goto coreaudio_error;
+
+    return CONTROL_OK;
+
+coreaudio_error:
+    return CONTROL_ERROR;
+}
+
+#define OPT_BASE_STRUCT struct priv
+
+const struct ao_driver audio_out_audiounit = {
+    .description    = "AudioUnit (iOS)",
+    .name           = "audiounit",
+    .uninit         = uninit,
+    .init           = init,
+    .pause          = stop,
+    .resume         = start,
+    .priv_size      = sizeof(struct priv),
+    .options = (const struct m_option[]){
+        {0}
+    },
+};