From 6981cefcd1db2b3241f479f7a8fe80217bd76d6e Mon Sep 17 00:00:00 2001
From: Martin Pulec <pulec@cesnet.cz>
Date: Fri, 22 Feb 2019 18:26:54 +0100
Subject: [PATCH] CoreAudio: capture 128 frames

Capture only 128 frames at once (implicit value was 512).

+ param to allow user to set it manually
---
 src/audio/capture/coreaudio.c | 15 +++++++++++++++
 src/host.cpp                  |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/src/audio/capture/coreaudio.c b/src/audio/capture/coreaudio.c
index ae8eb9122..1a0e1f661 100644
--- a/src/audio/capture/coreaudio.c
+++ b/src/audio/capture/coreaudio.c
@@ -61,6 +61,7 @@
 #include "utils/ring_buffer.h"
 
 #define DISABLE_SPPEX_RESAMPLER 1
+#define MODULE_NAME "[CoreAudio] "
 
 struct state_ca_capture {
 #if OS_VERSION_MAJOR <= 9
@@ -229,6 +230,13 @@ error:
         fprintf(stderr, "[CoreAudio] error obtaining device list.\n");
 }
 
+#define CHECK_OK(cmd, msg, action_failed) do { int ret = cmd; if (!ret) {\
+        log_msg(LOG_LEVEL_WARNING, MODULE_NAME "%s\n", (msg));\
+        action_failed;\
+}\
+} while(0)
+#define NOOP ((void)0)
+
 static void * audio_cap_ca_init(const char *cfg)
 {
         if(cfg && strcmp(cfg, "help") == 0) {
@@ -430,6 +438,13 @@ static void * audio_cap_ca_init(const char *cfg)
                         fprintf(stderr, "[CoreAudio] Error setting input callback.\n");
                         goto error;
                 }
+                uint32_t numFrames = 128;
+                if (get_commandline_param("audio-cap-frames")) {
+                        numFrames = atoi(get_commandline_param("audio-cap-frames"));
+                }
+                CHECK_OK(AudioUnitSetProperty(s->auHALComponentInstance, kAudioDevicePropertyBufferFrameSize,
+                                        kAudioUnitScope_Global, 0, &numFrames, sizeof(numFrames)),
+                                        "[CoreAudio] Error setting frames.", NOOP);
         }
 
         ret = AudioUnitInitialize(s->auHALComponentInstance);
diff --git a/src/host.cpp b/src/host.cpp
index 825ede421..85d539657 100644
--- a/src/host.cpp
+++ b/src/host.cpp
@@ -395,6 +395,8 @@ bool register_mainloop(mainloop_t m, void *u)
 // some common parameters used within multiple modules
 ADD_TO_PARAM(audio_buffer_len, "audio-buffer-len", "* audio-buffer-len=<ms>\n"
                 "  Sets length of software audio playback buffer (in ms, ALSA/Coreaudio/Portaudio)\n");
+ADD_TO_PARAM(audio_cap_frames, "audio-cap-frames", "* audio-cap-frames=<f>\n"
+                "  Sets number of audio frames captured at once (CoreAudio)\n");
 ADD_TO_PARAM(low_latency_audio, "low-latency-audio", "* low-latency-audio\n"
                 "  Try to reduce audio latency at the expense of worse reliability\n");
 ADD_TO_PARAM(window_title, "window-title", "* window-title=<title>\n"