If no input device is found, exit

friture/audiobackend.py

@@ -65,6 +65,8 @@ def __init__(self, logger):
         self.first_channel = None
         self.second_channel = None
 
+        self.stream = None
+
         # we will try to open all the input devices until one
         # works, starting by the default input device
         for device in self.input_devices:
@@ -104,8 +106,13 @@ def get_readable_devices_list(self):
         input_devices = self.get_input_devices()
 
         raw_devices = sounddevice.query_devices()
-        default_input_device = sounddevice.query_devices(kind='input')
-        default_input_device['index'] = raw_devices.index(default_input_device)
+
+        try:
+            default_input_device = sounddevice.query_devices(kind='input')
+            default_input_device['index'] = raw_devices.index(default_input_device)
+        except sounddevice.PortAudioError as exception:
+            self.logger.push("Failed to query the default input device: %s" % (exception))
+            default_input_device = None
 
         devices_list = []
         for device in input_devices:
@@ -172,7 +179,19 @@ def get_default_output_device(self):
     def get_input_devices(self):
         devices = sounddevice.query_devices()
 
-        default_input_device = sounddevice.query_devices(kind='input')
+        # early exit if there is no input device. Otherwise query_devices(kind='input') fails
+        input_devices = [device for device in devices if device['max_input_channels'] > 0]
+
+        print(input_devices)
+
+        if len(input_devices) == 0:
+            return []
+
+        try:
+            default_input_device = sounddevice.query_devices(kind='input')
+        except sounddevice.PortAudioError as exception:
+            self.logger.push("Failed to query the default input device: %s" % (exception))
+            default_input_device = None
 
         input_devices = []
         if default_input_device is not None:
@@ -398,7 +417,9 @@ def get_stream_time(self):
             return 0
 
     def pause(self):
-        self.stream.stop()
+        if self.stream != None:
+            self.stream.stop()
 
     def restart(self):
-        self.stream.start()
+        if self.stream != None:
+            self.stream.start()

friture/settings.py

@@ -17,14 +17,15 @@
 # You should have received a copy of the GNU General Public License
 # along with Friture.  If not, see <http://www.gnu.org/licenses/>.
 
+import sys
 from PyQt5 import QtCore, QtWidgets
 from friture.ui_settings import Ui_Settings_Dialog
 
 no_input_device_title = "No audio input device found"
 
 no_input_device_message = """No audio input device has been found.
 
-Please check your audio configuration.
+Friture needs at least one input device. Please check your audio configuration.
 
 Friture will now exit.
 """
@@ -48,6 +49,7 @@ def __init__(self, parent, logger, audiobackend):
             # no audio input device: display a message and exit
             QtWidgets.QMessageBox.critical(self, no_input_device_title, no_input_device_message)
             QtCore.QTimer.singleShot(0, self.exitOnInit)
+            sys.exit(1)
             return
 
         for device in devices: