[AUDIO_WORKLET] Add multichannel audio tests. NFC (#23394)

These are the audio worklet tests from #22753 extracted to a standalone
PR. The tests are:

- Multiple stereo inputs mixing in the processor to a single stereo
output
- Multiple stereo inputs copying in the processor to multiple stereo
outputs
- Multiple mono inputs mixing in the processor to a single mono output
- Multiple mono inputs copying in the processor to L+R stereo outputs

The tests use different stack sizes (from 2kB to 6kB depending on the
requirement).

The audio tracks were composed by Tim Wright especially for Emscripten
and released under a CC0 license.

Author: cwoffenden

test/test_browser.py

@@ -5454,6 +5454,18 @@ def test_audio_worklet_post_function(self, args):
   def test_audio_worklet_modularize(self, args):
     self.btest_exit('webaudio/audioworklet.c', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS', '-sMODULARIZE=1', '-sEXPORT_NAME=MyModule', '--shell-file', test_file('shell_that_launches_modularize.html')] + args)
 
+  # Tests multiple inputs, forcing a larger stack (note: passing BROWSER_TEST is
+  # specific to this test to allow it to exit rather than play forever).
+  @parameterized({
+    '': ([],),
+    'minimal_with_closure': (['-sMINIMAL_RUNTIME', '--closure=1', '-Oz'],),
+  })
+  def test_audio_worklet_stereo_io(self, args):
+    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_exit('webaudio/audioworklet_in_out_stereo.c', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS', '-DBROWSER_TEST'] + args)
+
   def test_error_reporting(self):
     # Test catching/reporting Error objects
     create_file('post.js', 'throw new Error("oops");')

test/test_interactive.py

@@ -306,6 +306,34 @@ def test_audio_worklet_tone_generator(self):
   def test_audio_worklet_modularize(self):
     self.btest('webaudio/audioworklet.c', expected='0', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS', '-sMINIMAL_RUNTIME', '-sMODULARIZE'])
 
+  # Tests an AudioWorklet with multiple stereo inputs mixing in the processor to a single stereo output (4kB stack)
+  def test_audio_worklet_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_exit('webaudio/audioworklet_in_out_stereo.c', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS'])
+
+  # Tests an AudioWorklet with multiple stereo inputs copying in the processor to multiple stereo outputs (6kB stack)
+  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_exit('webaudio/audioworklet_2x_in_out_stereo.c', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS'])
+
+  # Tests an AudioWorklet with multiple mono inputs mixing in the processor to a single mono output (2kB stack)
+  def test_audio_worklet_mono_io(self):
+    os.mkdir('audio_files')
+    shutil.copy(test_file('webaudio/audio_files/emscripten-beat-mono.mp3'), 'audio_files/')
+    shutil.copy(test_file('webaudio/audio_files/emscripten-bass-mono.mp3'), 'audio_files/')
+    self.btest_exit('webaudio/audioworklet_in_out_mono.c', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS'])
+
+  # Tests an AudioWorklet with multiple mono inputs copying in the processor to L+R stereo outputs (3kB stack)
+  def test_audio_worklet_2x_hard_pan_io(self):
+    os.mkdir('audio_files')
+    shutil.copy(test_file('webaudio/audio_files/emscripten-beat-mono.mp3'), 'audio_files/')
+    shutil.copy(test_file('webaudio/audio_files/emscripten-bass-mono.mp3'), 'audio_files/')
+    self.btest_exit('webaudio/audioworklet_2x_in_hard_pan.c', args=['-sAUDIO_WORKLET', '-sWASM_WORKERS'])
+
 
 class interactive64(interactive):
   def setUp(self):

test/webaudio/audio_files/README.md

@@ -0,0 +1,5 @@
+Emscripten Beat and Emscripten Bass by [CoLD SToRAGE](https://www.coldstorage.org.uk) (Tim Wright).
+
+Released under the [Creative Commons Zero (CC0)](https://creativecommons.org/publicdomain/zero/1.0/) Public Domain Dedication.
+
+To the extent possible under law, OGP Phonogramatica has waived all copyright and related or neighbouring rights to these works.

test/webaudio/audio_files/emscripten-bass-mono.mp3

@@ -0,0 +1,70 @@
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <emscripten/em_js.h>
+#include <emscripten/webaudio.h>
+
+// Tests two mono audio inputs being copied to the left and right channels of a
+// single stereo output (with a hard pan).
+
+// This needs to be big enough for the stereo output, 2x mono inputs and the worker stack
+#define AUDIO_STACK_SIZE 3072
+
+// Shared file playback and bootstrap
+#include "audioworklet_test_shared.inc"
+
+// 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) {
+  audioProcessedCount++;
+
+  // Twin mono in, single stereo out
+  assert(numInputs == 2 && numOutputs == 1);
+  assert(inputs[0].numberOfChannels == 1 && inputs[1].numberOfChannels == 1);
+  assert(outputs[0].numberOfChannels == 2);
+  // All with the same number of samples
+  assert(inputs[0].samplesPerChannel == inputs[1].samplesPerChannel);
+  assert(inputs[0].samplesPerChannel == outputs[0].samplesPerChannel);
+  // Now with all known quantities we can memcpy the data
+  int samplesPerChannel = inputs[0].samplesPerChannel;
+  memcpy(outputs[0].data, inputs[0].data, samplesPerChannel * sizeof(float));
+  memcpy(outputs[0].data + samplesPerChannel, inputs[1].data, samplesPerChannel * sizeof(float));
+  return true;
+}
+
+// Audio processor created, now register the audio callback
+void processorCreated(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
+  if (!success) {
+    printf("Audio worklet node creation failed\n");
+    return;
+  }
+  printf("Audio worklet processor created\n");
+  printf("Click to toggle audio playback\n");
+
+  // Stereo output, two inputs
+  int outputChannelCounts[2] = { 2 };
+  EmscriptenAudioWorkletNodeCreateOptions opts = {
+    .numberOfInputs  = 2,
+    .numberOfOutputs = 1,
+    .outputChannelCounts = outputChannelCounts
+  };
+  EMSCRIPTEN_AUDIO_WORKLET_NODE_T worklet = emscripten_create_wasm_audio_worklet_node(context, "mixer", &opts, &process, NULL);
+  emscripten_audio_node_connect(worklet, context, 0, 0);
+
+  // Create the two mono 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-mono.mp3", true);
+  if (beatID) {
+    emscripten_audio_node_connect(beatID, worklet, 0, 0);
+  }
+  bassID = createTrack(context, "audio_files/emscripten-bass-mono.mp3", true);
+  if (bassID) {
+    emscripten_audio_node_connect(bassID, worklet, 0, 1);
+  }
+
+  // Register a click to start playback
+  emscripten_set_click_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, WA_2_VOIDP(context), false, &onClick);
+
+  // Register the counter that exits the test after one second of mixing
+  emscripten_set_timeout_loop(&playedAndMixed, 16, NULL);
+}

test/webaudio/audio_files/emscripten-bass.mp3

@@ -0,0 +1,72 @@
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <emscripten/em_js.h>
+#include <emscripten/webaudio.h>
+
+// Tests 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
+
+// Shared file playback and bootstrap
+#include "audioworklet_test_shared.inc"
+
+// 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) {
+  audioProcessedCount++;
+
+  // 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;
+}
+
+// Audio processor created, now register the audio callback
+void processorCreated(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
+  if (!success) {
+    printf("Audio worklet node creation failed\n");
+    return;
+  }
+  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);
+  }
+
+  // Register a click to start playback
+  emscripten_set_click_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, WA_2_VOIDP(context), false, &onClick);
+
+  // Register the counter that exits the test after one second of mixing
+  emscripten_set_timeout_loop(&playedAndMixed, 16, NULL);
+}

test/webaudio/audio_files/emscripten-beat-mono.mp3

@@ -0,0 +1,82 @@
+#include <assert.h>
+#include <string.h>
+#include <stdio.h>
+
+#include <emscripten/em_js.h>
+#include <emscripten/webaudio.h>
+
+// Tests processing two mono audio inputs being mixed to a single mono audio
+// output in process() (by adding the inputs together).
+
+// This needs to be big enough for the mono output, 2x inputs and the worker stack
+#define AUDIO_STACK_SIZE 2048
+
+// Shared file playback and bootstrap
+#include "audioworklet_test_shared.inc"
+
+// Callback to process and mix the audio tracks
+bool process(int numInputs, const AudioSampleFrame* inputs, int numOutputs, AudioSampleFrame* outputs, int numParams, const AudioParamFrame* params, void* data) {
+  audioProcessedCount++;
+
+  // Single mono output
+  assert(numOutputs == 1 && outputs[0].numberOfChannels == 1);
+  for (int n = 0; n < numInputs; n++) {
+    // And all inputs are also stereo
+    assert(inputs[n].numberOfChannels == 1 || inputs[n].numberOfChannels == 0);
+    // This should always be the case
+    assert(inputs[n].samplesPerChannel == outputs[0].samplesPerChannel);
+  }
+  // We can now do a quick mix since we know the layouts
+  if (numInputs > 0) {
+    int totalSamples = outputs[0].samplesPerChannel * outputs[0].numberOfChannels;
+    float* outputData = outputs[0].data;
+    memcpy(outputData, inputs[0].data, totalSamples * sizeof(float));
+    for (int n = 1; n < numInputs; n++) {
+      // It's possible to have an input with no channels
+      if (inputs[n].numberOfChannels == 1) {
+        float* inputData = inputs[n].data;
+        for (int i = totalSamples - 1; i >= 0; i--) {
+          outputData[i] += inputData[i];
+        }
+      }
+    }
+  }
+  return true;
+}
+
+// Audio processor created, now register the audio callback
+void processorCreated(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
+  if (!success) {
+    printf("Audio worklet node creation failed\n");
+    return;
+  }
+  printf("Audio worklet processor created\n");
+  printf("Click to toggle audio playback\n");
+
+  // Mono output, two inputs
+  int outputChannelCounts[1] = { 1 };
+  EmscriptenAudioWorkletNodeCreateOptions opts = {
+    .numberOfInputs  = 2,
+    .numberOfOutputs = 1,
+    .outputChannelCounts = outputChannelCounts
+  };
+  EMSCRIPTEN_AUDIO_WORKLET_NODE_T worklet = emscripten_create_wasm_audio_worklet_node(context, "mixer", &opts, &process, NULL);
+  emscripten_audio_node_connect(worklet, context, 0, 0);
+
+  // Create the two mono 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-mono.mp3", true);
+  if (beatID) {
+    emscripten_audio_node_connect(beatID, worklet, 0, 0);
+  }
+  bassID = createTrack(context, "audio_files/emscripten-bass-mono.mp3", true);
+  if (bassID) {
+    emscripten_audio_node_connect(bassID, worklet, 0, 1);
+  }
+
+  // Register a click to start playback
+  emscripten_set_click_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, WA_2_VOIDP(context), false, &onClick);
+
+  // Register the counter that exits the test after one second of mixing
+  emscripten_set_timeout_loop(&playedAndMixed, 16, NULL);
+}

test/webaudio/audio_files/emscripten-beat.mp3

@@ -0,0 +1,82 @@
+#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 mixed to a single stereo audio
+// output in process() (by adding the inputs together).
+
+// This needs to be big enough for the stereo output, 2x inputs and the worker stack
+#define AUDIO_STACK_SIZE 4096
+
+// Shared file playback and bootstrap
+#include "audioworklet_test_shared.inc"
+
+// Callback to process and mix the audio tracks
+bool process(int numInputs, const AudioSampleFrame* inputs, int numOutputs, AudioSampleFrame* outputs, int numParams, const AudioParamFrame* params, void* data) {
+  audioProcessedCount++;
+
+  // Single stereo output
+  assert(numOutputs == 1 && outputs[0].numberOfChannels == 2);
+  for (int n = 0; n < numInputs; n++) {
+    // And all inputs are also stereo
+    assert(inputs[n].numberOfChannels == 2 || inputs[n].numberOfChannels == 0);
+    // This should always be the case
+    assert(inputs[n].samplesPerChannel == outputs[0].samplesPerChannel);
+  }
+  // We can now do a quick mix since we know the layouts
+  if (numInputs > 0) {
+    int totalSamples = outputs[0].samplesPerChannel * outputs[0].numberOfChannels;
+    float* outputData = outputs[0].data;
+    memcpy(outputData, inputs[0].data, totalSamples * sizeof(float));
+    for (int n = 1; n < numInputs; n++) {
+      // It's possible to have an input with no channels
+      if (inputs[n].numberOfChannels == 2) {
+        float* inputData = inputs[n].data;
+        for (int i = totalSamples - 1; i >= 0; i--) {
+          outputData[i] += inputData[i];
+        }
+      }
+    }
+  }
+  return true;
+}
+
+// Audio processor created, now register the audio callback
+void processorCreated(EMSCRIPTEN_WEBAUDIO_T context, bool success, void* data) {
+  if (!success) {
+    printf("Audio worklet node creation failed\n");
+    return;
+  }
+  printf("Audio worklet processor created\n");
+  printf("Click to toggle audio playback\n");
+
+  // Stereo output, two inputs
+  int outputChannelCounts[1] = { 2 };
+  EmscriptenAudioWorkletNodeCreateOptions opts = {
+    .numberOfInputs  = 2,
+    .numberOfOutputs = 1,
+    .outputChannelCounts = outputChannelCounts
+  };
+  EMSCRIPTEN_AUDIO_WORKLET_NODE_T worklet = emscripten_create_wasm_audio_worklet_node(context, "mixer", &opts, &process, NULL);
+  emscripten_audio_node_connect(worklet, context, 0, 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);
+  }
+
+  // Register a click to start playback
+  emscripten_set_click_callback(EMSCRIPTEN_EVENT_TARGET_DOCUMENT, WA_2_VOIDP(context), false, &onClick);
+
+  // Register the counter that exits the test after one second of mixing
+  emscripten_set_timeout_loop(&playedAndMixed, 16, NULL);
+}