Added the AudioRecord API

mediapipe/tasks/python/audio/core/BUILD

@@ -34,5 +34,6 @@ py_library(
         "//mediapipe/python:_framework_bindings",
         "//mediapipe/python:packet_creator",
         "//mediapipe/tasks/python/core:optional_dependencies",
+        "//mediapipe/tasks/python/components/containers:audio_record",
     ],
 )

mediapipe/tasks/python/audio/core/base_audio_task_api.py

@@ -22,6 +22,7 @@ from mediapipe.python._framework_bindings import task_runner as task_runner_modu
 from mediapipe.python._framework_bindings import timestamp as timestamp_module
 from mediapipe.tasks.python.audio.core import audio_task_running_mode as running_mode_module
 from mediapipe.tasks.python.core.optional_dependencies import doc_controls
+from mediapipe.tasks.python.components.containers import audio_record
 
 _TaskRunner = task_runner_module.TaskRunner
 _Packet = packet_module.Packet
@@ -126,6 +127,33 @@ class BaseAudioTaskApi(object):
           + self._running_mode.name)
     self._runner.send(inputs)
 
+  @staticmethod
+  def create_audio_record(
+      num_channels: int,
+      sample_rate: int,
+      required_input_buffer_size: int
+  ) -> audio_record.AudioRecord:
+    """Creates an AudioRecord instance to record audio stream.
+
+    The returned AudioRecord instance is initialized and client needs to call
+    the appropriate method to start recording.
+
+    Note that MediaPipe Audio tasks will up/down sample automatically to fit the
+    sample rate required by the model. The default sample rate of the MediaPipe
+    pretrained audio model, Yamnet is 16kHz.
+
+    Args:
+      num_channels: The number of audio channels.
+      sample_rate: The audio sample rate.
+      required_input_buffer_size: The required input buffer size in number of
+        float elements.
+
+    Raises:
+      ValueError: If there's a problem creating the AudioRecord instance.
+    """
+    return audio_record.AudioRecord(num_channels, sample_rate,
+                                    required_input_buffer_size)
+
   def close(self) -> None:
     """Shuts down the mediapipe audio task instance.
 

mediapipe/tasks/python/components/containers/BUILD

@@ -23,6 +23,11 @@ py_library(
     srcs = ["audio_data.py"],
 )
 
+py_library(
+    name = "audio_record",
+    srcs = ["audio_record.py"],
+)
+
 py_library(
     name = "bounding_box",
     srcs = ["bounding_box.py"],

mediapipe/tasks/python/components/containers/audio_record.py

@@ -0,0 +1,126 @@
+# Copyright 2023 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""A module to record audio in a streaming basis."""
+import threading
+import numpy as np
+
+try:
+# pylint: disable=g-import-not-at-top
+  import sounddevice as sd
+# pylint: enable=g-import-not-at-top
+except OSError as oe:
+  sd = None
+  sd_error = oe
+except ImportError as ie:
+  sd = None
+  sd_error = ie
+
+
+class AudioRecord(object):
+  """A class to record audio in a streaming basis."""
+
+  def __init__(self, channels: int, sampling_rate: int,
+               buffer_size: int) -> None:
+    """Creates an AudioRecord instance.
+
+    Args:
+      channels: Number of input channels.
+      sampling_rate: Sampling rate in Hertz.
+      buffer_size: Size of the ring buffer in number of samples.
+
+    Raises:
+      ValueError: if any of the arguments is non-positive.
+      ImportError: if failed to import `sounddevice`.
+      OSError: if failed to load `PortAudio`.
+    """
+    if sd is None:
+      raise sd_error
+
+    if channels <= 0:
+      raise ValueError('channels must be postive.')
+    if sampling_rate <= 0:
+      raise ValueError('sampling_rate must be postive.')
+    if buffer_size <= 0:
+      raise ValueError('buffer_size must be postive.')
+
+    self._audio_buffer = []
+    self._buffer_size = buffer_size
+    self._channels = channels
+    self._sampling_rate = sampling_rate
+
+    # Create a ring buffer to store the input audio.
+    self._buffer = np.zeros([buffer_size, channels], dtype=float)
+    self._lock = threading.Lock()
+
+    def audio_callback(data, *_):
+      """A callback to receive recorded audio data from sounddevice."""
+      self._lock.acquire()
+      shift = len(data)
+      if shift > buffer_size:
+        self._buffer = np.copy(data[:buffer_size])
+      else:
+        self._buffer = np.roll(self._buffer, -shift, axis=0)
+        self._buffer[-shift:, :] = np.copy(data)
+      self._lock.release()
+
+    # Create an input stream to continuously capture the audio data.
+    self._stream = sd.InputStream(
+        channels=channels,
+        samplerate=sampling_rate,
+        callback=audio_callback,
+    )
+
+  @property
+  def channels(self) -> int:
+    return self._channels
+
+  @property
+  def sampling_rate(self) -> int:
+    return self._sampling_rate
+
+  @property
+  def buffer_size(self) -> int:
+    return self._buffer_size
+
+  def start_recording(self) -> None:
+    """Starts the audio recording."""
+    # Clear the internal ring buffer.
+    self._buffer.fill(0)
+
+    # Start recording using sounddevice's InputStream.
+    self._stream.start()
+
+  def stop(self) -> None:
+    """Stops the audio recording."""
+    self._stream.stop()
+
+  def read(self, size: int) -> np.ndarray:
+    """Reads the latest audio data captured in the buffer.
+
+    Args:
+      size: Number of samples to read from the buffer.
+
+    Returns:
+      A NumPy array containing the audio data.
+
+    Raises:
+      ValueError: Raised if `size` is larger than the buffer size.
+    """
+    if size > self._buffer_size:
+      raise ValueError('Cannot read more samples than the size of the buffer.')
+    elif size <= 0:
+      raise ValueError('Size must be positive.')
+
+    start_index = self._buffer_size - size
+    return np.copy(self._buffer[start_index:])

mediapipe/tasks/python/test/audio/BUILD

@@ -29,6 +29,7 @@ py_test(
         "//mediapipe/tasks/python/audio:audio_classifier",
         "//mediapipe/tasks/python/audio/core:audio_task_running_mode",
         "//mediapipe/tasks/python/components/containers:audio_data",
+        "//mediapipe/tasks/python/components/containers:audio_record",
         "//mediapipe/tasks/python/components/containers:classification_result",
         "//mediapipe/tasks/python/core:base_options",
         "//mediapipe/tasks/python/test:test_utils",
@@ -46,6 +47,7 @@ py_test(
         "//mediapipe/tasks/python/audio:audio_embedder",
         "//mediapipe/tasks/python/audio/core:audio_task_running_mode",
         "//mediapipe/tasks/python/components/containers:audio_data",
+        "//mediapipe/tasks/python/components/containers:audio_record",
         "//mediapipe/tasks/python/components/containers:embedding_result",
         "//mediapipe/tasks/python/core:base_options",
         "//mediapipe/tasks/python/test:test_utils",

mediapipe/tasks/python/test/audio/audio_classifier_test.py

@@ -27,6 +27,7 @@ from mediapipe.tasks.python.audio import audio_classifier
 from mediapipe.tasks.python.audio.core import audio_task_running_mode
 from mediapipe.tasks.python.components.containers import audio_data as audio_data_module
 from mediapipe.tasks.python.components.containers import classification_result as classification_result_module
+from mediapipe.tasks.python.components.containers import audio_record
 from mediapipe.tasks.python.core import base_options as base_options_module
 from mediapipe.tasks.python.test import test_utils
 
@@ -34,6 +35,7 @@ _AudioClassifier = audio_classifier.AudioClassifier
 _AudioClassifierOptions = audio_classifier.AudioClassifierOptions
 _AudioClassifierResult = classification_result_module.ClassificationResult
 _AudioData = audio_data_module.AudioData
+_AudioRecord = audio_record.AudioRecord
 _BaseOptions = base_options_module.BaseOptions
 _RUNNING_MODE = audio_task_running_mode.AudioTaskRunningMode
 
@@ -204,6 +206,18 @@ class AudioClassifierTest(parameterized.TestCase):
             self._read_wav_file(audio_file))
         self._check_yamnet_result(classification_result_list)
 
+  @mock.patch("sounddevice.InputStream", return_value=mock.MagicMock())
+  def test_create_audio_record_from_classifier_succeeds(self, _):
+    # Creates AudioRecord instance using the classifier successfully.
+    with _AudioClassifier.create_from_model_path(
+        self.yamnet_model_path) as classifier:
+      self.assertIsInstance(classifier, _AudioClassifier)
+      record = classifier.create_audio_record(1, 16000, 16000)
+      self.assertIsInstance(record, _AudioRecord)
+      self.assertEqual(record.channels, 1)
+      self.assertEqual(record.sampling_rate, 16000)
+      self.assertEqual(record.buffer_size, 16000)
+
   def test_max_result_options(self):
     with _AudioClassifier.create_from_options(
         _AudioClassifierOptions(

mediapipe/tasks/python/test/audio/audio_embedder_test.py

@@ -26,6 +26,7 @@ from scipy.io import wavfile
 from mediapipe.tasks.python.audio import audio_embedder
 from mediapipe.tasks.python.audio.core import audio_task_running_mode
 from mediapipe.tasks.python.components.containers import audio_data as audio_data_module
+from mediapipe.tasks.python.components.containers import audio_record
 from mediapipe.tasks.python.core import base_options as base_options_module
 from mediapipe.tasks.python.test import test_utils
 
@@ -33,6 +34,7 @@ _AudioEmbedder = audio_embedder.AudioEmbedder
 _AudioEmbedderOptions = audio_embedder.AudioEmbedderOptions
 _AudioEmbedderResult = audio_embedder.AudioEmbedderResult
 _AudioData = audio_data_module.AudioData
+_AudioRecord = audio_record.AudioRecord
 _BaseOptions = base_options_module.BaseOptions
 _RUNNING_MODE = audio_task_running_mode.AudioTaskRunningMode
 
@@ -165,6 +167,18 @@ class AudioEmbedderTest(parameterized.TestCase):
       self.assertLen(embedding_result0_list, 5)
       self.assertLen(embedding_result1_list, 5)
 
+  @mock.patch("sounddevice.InputStream", return_value=mock.MagicMock())
+  def test_create_audio_record_from_embedder_succeeds(self, _):
+    # Creates AudioRecord instance using the embedder successfully.
+    with _AudioEmbedder.create_from_model_path(
+        self.yamnet_model_path) as embedder:
+      self.assertIsInstance(embedder, _AudioEmbedder)
+      record = embedder.create_audio_record(1, 16000, 16000)
+      self.assertIsInstance(record, _AudioRecord)
+      self.assertEqual(record.channels, 1)
+      self.assertEqual(record.sampling_rate, 16000)
+      self.assertEqual(record.buffer_size, 16000)
+
   def test_embed_with_yamnet_model_and_different_inputs(self):
     with _AudioEmbedder.create_from_model_path(
         self.yamnet_model_path) as embedder:

mediapipe/tasks/python/test/audio/core/BUILD

@@ -0,0 +1,27 @@
+# Copyright 2022 The MediaPipe Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Placeholder for internal Python strict test compatibility macro.
+
+package(default_visibility = ["//mediapipe/tasks:internal"])
+
+licenses(["notice"])
+
+py_test(
+    name = "audio_record_test",
+    srcs = ["audio_record_test.py"],
+    deps = [
+        "//mediapipe/tasks/python/components/containers:audio_record",
+    ],
+)

mediapipe/tasks/python/test/audio/core/audio_record_test.py

@@ -0,0 +1,97 @@
+# Copyright 2022 The TensorFlow Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""Tests for audio_record."""
+
+import numpy as np
+import unittest
+
+from absl.testing import absltest
+from absl.testing import parameterized
+from mediapipe.tasks.python.components.containers import audio_record
+
+_mock = unittest.mock
+
+_CHANNELS = 2
+_SAMPLING_RATE = 16000
+_BUFFER_SIZE = 15600
+
+
+class AudioRecordTest(parameterized.TestCase):
+
+  def setUp(self):
+    super().setUp()
+
+    # Mock sounddevice.InputStream
+    with _mock.patch("sounddevice.InputStream") as mock_input_stream_new_method:
+      self.mock_input_stream = _mock.MagicMock()
+      mock_input_stream_new_method.return_value = self.mock_input_stream
+      self.record = audio_record.AudioRecord(_CHANNELS, _SAMPLING_RATE,
+                                             _BUFFER_SIZE)
+
+      # Save the initialization arguments of InputStream for later assertion.
+      _, self.init_args = mock_input_stream_new_method.call_args
+
+  def test_init_args(self):
+    # Assert parameters of InputStream initialization
+    self.assertEqual(
+        self.init_args["channels"], _CHANNELS,
+        "InputStream's channels doesn't match the initialization argument.")
+    self.assertEqual(
+        self.init_args["samplerate"], _SAMPLING_RATE,
+        "InputStream's samplerate doesn't match the initialization argument.")
+
+  def test_life_cycle(self):
+    # Assert start recording routine.
+    self.record.start_recording()
+    self.mock_input_stream.start.assert_called_once()
+
+    # Assert stop recording routine.
+    self.record.stop()
+    self.mock_input_stream.stop.assert_called_once()
+
+  def test_read_succeeds_with_valid_sample_size(self):
+    callback_fn = self.init_args["callback"]
+
+    # Create dummy data to feed to the AudioRecord instance.
+    chunk_size = int(_BUFFER_SIZE * 0.5)
+    input_data = []
+    for _ in range(3):
+      dummy_data = np.random.rand(chunk_size, _CHANNELS).astype(float)
+      input_data.append(dummy_data)
+      callback_fn(dummy_data)
+
+    # Assert read data of a single chunk.
+    recorded_audio_data = self.record.read(chunk_size)
+    self.assertTrue(np.array_equal(recorded_audio_data, input_data[-1]))
+
+    # Assert read all data in buffer.
+    recorded_audio_data = self.record.read(chunk_size * 2)
+    print(input_data[-2].shape)
+    expected_data = np.concatenate(input_data[-2:])
+    self.assertTrue(np.array_equal(recorded_audio_data, expected_data))
+
+  def test_read_fails_with_invalid_sample_size(self):
+    callback_fn = self.init_args["callback"]
+
+    # Create dummy data to feed to the AudioRecord instance.
+    dummy_data = np.zeros([_BUFFER_SIZE, 1], dtype=float)
+    callback_fn(dummy_data)
+
+    # Assert exception if read too much data.
+    with self.assertRaises(ValueError):
+      self.record.read(_BUFFER_SIZE + 1)
+
+
+if __name__ == "__main__":
+  absltest.main()