Fixing sounddevice stream active state recovery and adding corresponding exceptions

lerobot/common/robot_devices/microphones/microphone.py

@@ -35,6 +35,8 @@ from lerobot.common.robot_devices.microphones.configs import MicrophoneConfig
 from lerobot.common.robot_devices.utils import (
     RobotDeviceAlreadyConnectedError,
     RobotDeviceNotConnectedError,
+    RobotDeviceNotRecordingError,
+    RobotDeviceAlreadyRecordingError,
     busy_wait,
 )
 
@@ -152,6 +154,7 @@ class Microphone:
 
         self.logs = {}
         self.is_connected = False
+        self.is_recording = False
 
     def connect(self) -> None:
         if self.is_connected:
@@ -250,8 +253,8 @@ class Microphone:
 
         if not self.is_connected:
             raise RobotDeviceNotConnectedError(f"Microphone {self.microphone_index} is not connected.")
-        if not self.stream.active:
+        if not self.is_recording:
-            raise RuntimeError(f"Microphone {self.microphone_index} is not recording.")
+            raise RobotDeviceNotRecordingError(f"Microphone {self.microphone_index} is not recording.")
         
         start_time = time.perf_counter()
 
@@ -269,6 +272,8 @@ class Microphone:
 
         if not self.is_connected:
             raise RobotDeviceNotConnectedError(f"Microphone {self.microphone_index} is not connected.")
+        if self.is_recording:
+            raise RobotDeviceAlreadyRecordingError(f"Microphone {self.microphone_index} is already recording.")
         
         self.read_queue = Queue()
         with self.read_queue.mutex:
@@ -291,12 +296,15 @@ class Microphone:
             self.record_thread.daemon = True
             self.record_thread.start()
             
+        self.is_recording = True
         self.stream.start()
 
     def stop_recording(self) -> None:
 
         if not self.is_connected:
             raise RobotDeviceNotConnectedError(f"Microphone {self.microphone_index} is not connected.")
+        if not self.is_recording:
+            raise RobotDeviceNotRecordingError(f"Microphone {self.microphone_index} is not recording.")
         
         if self.record_thread is not None:
             #self.record_queue.join()
@@ -309,12 +317,14 @@ class Microphone:
             self.stream.stop()  #Wait for all buffers to be processed
             #Remark : stream.abort() flushes the buffers !
 
+        self.is_recording = False
+
     def disconnect(self) -> None:
 
         if not self.is_connected:
             raise RobotDeviceNotConnectedError(f"Microphone {self.microphone_index} is not connected.")
 
-        if self.stream.active:
+        if self.is_recording:
             self.stop_recording()
 
         self.stream.close()

lerobot/common/robot_devices/utils.py

@@ -63,3 +63,23 @@ class RobotDeviceAlreadyConnectedError(Exception):
     ):
         self.message = message
         super().__init__(self.message)
+
+
+class RobotDeviceNotRecordingError(Exception):
+    """Exception raised when the robot device is not recording."""
+
+    def __init__(
+        self, message="This robot device is not recording. Try calling `robot_device.start_recording()` first."
+    ):
+        self.message = message
+        super().__init__(self.message)
+
+class RobotDeviceAlreadyRecordingError(Exception):
+    """Exception raised when the robot device is already recording."""
+
+    def __init__(
+        self,
+        message="This robot device is already recording. Try not calling `robot_device.start_recording()` twice.",
+    ):
+        self.message = message
+        super().__init__(self.message)