Added two audio ins to two audio outs test

Author: cwoffenden

test/test_interactive.py

@@ -313,6 +313,13 @@ def test_audio_worklet_stereo_io(self):
     shutil.copy(test_file('webaudio/audio_files/emscripten-bass.mp3'), 'audio_files/')
     self.btest('webaudio/audioworklet_in_out_stereo.c', expected='0', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS'])
 
+  # Tests an AudioWorklet with multiple stereo inputs copying in the processor to multiple stereo outputs
+  def test_audio_worklet_2x_stereo_io(self):
+    os.mkdir('audio_files')
+    shutil.copy(test_file('webaudio/audio_files/emscripten-beat.mp3'), 'audio_files/')
+    shutil.copy(test_file('webaudio/audio_files/emscripten-bass.mp3'), 'audio_files/')
+    self.btest('webaudio/audioworklet_2x_in_out_stereo.c', expected='0', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS'])
+
 
 class interactive64(interactive):
   def setUp(self):

test/webaudio/audioworklet_2x_in_out_stereo.c

@@ -0,0 +1,151 @@
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <emscripten/em_js.h>
+#include <emscripten/webaudio.h>
+
+// Tests processing two stereo audio inputs being copied to two stereo outputs.
+
+// This needs to be big enough for the 2x stereo outputs, 2x inputs and the worker stack
+#define AUDIO_STACK_SIZE 6144
+
+// REPORT_RESULT is defined when running in Emscripten test harness.
+#ifdef REPORT_RESULT
+// Count the mixed frames and return after 375 frames (1 second with the default 128 size)
+volatile int audioProcessedCount = 0;
+bool playedAndMixed(double time, void* data) {
+	if (audioProcessedCount >= 375) {
+		REPORT_RESULT(0);
+		return false;
+	}
+	return true;
+}
+#endif
+
+// ID to the beat and bass loops
+EMSCRIPTEN_WEBAUDIO_T beatID = 0;
+EMSCRIPTEN_WEBAUDIO_T bassID = 0;
+
+// Creates a MediaElementAudioSourceNode with the supplied URL (which is
+// registered as an internal audio object and the ID returned).
+EM_JS(EMSCRIPTEN_WEBAUDIO_T, createTrack, (EMSCRIPTEN_WEBAUDIO_T ctxID, const char* url, bool looping), {
+	var context = emscriptenGetAudioObject(ctxID);
+	if (context) {
+		var audio = document.createElement('audio');
+		audio.src = UTF8ToString(url);
+		audio.loop = looping;
+		var track = context.createMediaElementSource(audio);
+		return emscriptenRegisterAudioObject(track);
+	}
+	return 0;
+});
+
+// Toggles the play/pause of a MediaElementAudioSourceNode given its ID
+EM_JS(void, toggleTrack, (EMSCRIPTEN_WEBAUDIO_T srcID), {
+	var source = emscriptenGetAudioObject(srcID);
+	if (source) {
+		var audio = source.mediaElement;
+		if (audio) {
+			if (audio.paused) {
+				audio.currentTime = 0;
+				audio.play();
+			} else {
+				audio.pause();
+			}
+		}
+	}
+});
+
+// Callback to process and copy the audio tracks
+bool process(int numInputs, const AudioSampleFrame* inputs, int numOutputs, AudioSampleFrame* outputs, int numParams, const AudioParamFrame* params, void* data) {
+#ifdef REPORT_RESULT
+	audioProcessedCount++;
+#endif
+	// Twin stereo in and out
+	assert(numInputs == 2 && numOutputs == 2);
+	assert(inputs[0].numberOfChannels == 2 && inputs[1].numberOfChannels == 2);
+	assert(outputs[0].numberOfChannels == 2 && outputs[1].numberOfChannels == 2);
+	// All with the same number of samples
+	assert(inputs[0].samplesPerChannel == inputs[1].samplesPerChannel);
+	assert(inputs[0].samplesPerChannel == outputs[0].samplesPerChannel);
+	assert(outputs[0].samplesPerChannel == outputs[1].samplesPerChannel);
+	// Now with all known quantities we can memcpy the data
+	int totalSamples = outputs[0].samplesPerChannel * outputs[0].numberOfChannels;
+	memcpy(outputs[0].data, inputs[0].data, totalSamples * sizeof(float));
+	memcpy(outputs[1].data, inputs[1].data, totalSamples * sizeof(float));
+	return true;
+}
+
+// Registered click even to (1) enable audio playback and (2) toggle playing the tracks
+bool onClick(int type, const EmscriptenMouseEvent* e, void* data) {
+	EMSCRIPTEN_WEBAUDIO_T ctx = (EMSCRIPTEN_WEBAUDIO_T) (data);
+	if (emscripten_audio_context_state(ctx) != AUDIO_CONTEXT_STATE_RUNNING) {
+		printf("Resuming playback\n");
+		emscripten_resume_audio_context_sync(ctx);
+	}
+	printf("Toggling audio playback\n");
+	toggleTrack(beatID);
+    toggleTrack(bassID);
+	return false;
+}
+
+// Audio processor created, now register the audio callback
+void processorCreated(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
+	if (success) {
+		printf("Audio worklet processor created\n");
+		printf("Click to toggle audio playback\n");
+
+		// Two stereo outputs, two inputs
+		int outputChannelCounts[2] = { 2, 2 };
+		EmscriptenAudioWorkletNodeCreateOptions opts = {
+			.numberOfInputs  = 2,
+			.numberOfOutputs = 2,
+			.outputChannelCounts = outputChannelCounts
+		};
+		EMSCRIPTEN_AUDIO_WORKLET_NODE_T worklet = emscripten_create_wasm_audio_worklet_node(context, "mixer", &opts, &process, NULL);
+		// Both outputs connected to the context
+		emscripten_audio_node_connect(worklet, context, 0, 0);
+		emscripten_audio_node_connect(worklet, context, 1, 0);
+
+		// Create the two stereo source nodes and connect them to the two inputs
+		// Note: we can connect the sources to the same input and it'll get mixed for us, but that's not the point
+		beatID = createTrack(context, "audio_files/emscripten-beat.mp3", true);
+		if (beatID) {
+			emscripten_audio_node_connect(beatID, worklet, 0, 0);
+		}
+		bassID = createTrack(context, "audio_files/emscripten-bass.mp3", true);
+		if (bassID) {
+			emscripten_audio_node_connect(bassID, worklet, 0, 1);
+		}
+		
+		emscripten_set_click_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, (void*) (context), false, &onClick);
+		
+#ifdef REPORT_RESULT
+		emscripten_set_timeout_loop(&playedAndMixed, 16, NULL);
+#endif
+	} else {
+		printf("Audio worklet node creation failed\n");
+	}
+}
+
+// Worklet thread inited, now create the audio processor
+void initialised(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
+	if (success) {
+		printf("Audio worklet initialised\n");
+
+		WebAudioWorkletProcessorCreateOptions opts = {
+			.name = "mixer",
+		};
+		emscripten_create_wasm_audio_worklet_processor_async(context, &opts, &processorCreated, NULL);
+	} else {
+		printf("Audio worklet failed to initialise\n");
+	}
+}
+
+int main() {
+	static char workletStack[AUDIO_STACK_SIZE];
+	EMSCRIPTEN_WEBAUDIO_T context = emscripten_create_audio_context(NULL);
+	emscripten_start_wasm_audio_worklet_thread_async(context, workletStack, sizeof workletStack, &initialised, NULL);
+	return 0;
+}