Query registry for active webcam

webcamDetect.py

# 2024-04-17: Stole changese from @Timmo on stackoverflow to get this working with Windows Apps

import winreg

class WebcamDetect:
    REG_KEY = winreg.HKEY_CURRENT_USER
    WEBCAM_REG_SUBKEY = "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\CapabilityAccessManager\\ConsentStore\\webcam\\"
    WEBCAM_TIMESTAMP_VALUE_NAME = "LastUsedTimeStop"

    def __init__(self):
        self._regKey = winreg.OpenKey( WebcamDetect.REG_KEY, WebcamDetect.WEBCAM_REG_SUBKEY )

    def getActiveApps(self):
        """Returns a list of apps that are currently using the webcam."""

        def get_subkey_timestamp(subkey) -> int:
            """Returns the timestamp of the subkey"""
            try:
                value, _ = winreg.QueryValueEx(subkey, WebcamDetect.WEBCAM_TIMESTAMP_VALUE_NAME)
                return value
            except OSError:
                pass
            return None
        active_apps = []
        try:
            key = winreg.OpenKey(WebcamDetect.REG_KEY, WebcamDetect.WEBCAM_REG_SUBKEY)
            # Enumerate over the subkeys of the webcam key
            subkey_count, _, _ = winreg.QueryInfoKey(key)
            # Recursively open each subkey and check the "LastUsedTimeStop" value.
            # A value of 0 means the camera is currently in use.
            for idx in range(subkey_count):
                subkey_name = winreg.EnumKey(key, idx)
                subkey_name_full = f"{WebcamDetect.WEBCAM_REG_SUBKEY}\\{subkey_name}"
                subkey = winreg.OpenKey(WebcamDetect.REG_KEY, subkey_name_full)
                if subkey_name == "NonPackaged":
                    # Enumerate over the subkeys of the "NonPackaged" key
                    subkey_count, _, _ = winreg.QueryInfoKey(subkey)
                    for np_idx in range(subkey_count):
                        subkey_name_np = winreg.EnumKey(subkey, np_idx)
                        subkey_name_full_np = f"{WebcamDetect.WEBCAM_REG_SUBKEY}\\NonPackaged\\{subkey_name_np}"
                        subkey_np = winreg.OpenKey(WebcamDetect.REG_KEY, subkey_name_full_np)
                        if get_subkey_timestamp(subkey_np) == 0:
                            active_apps.append(subkey_name_np)
                else:
                    if get_subkey_timestamp(subkey) == 0:
                        active_apps.append(subkey_name)
                winreg.CloseKey(subkey)
            winreg.CloseKey(key)
        except OSError:
            pass
        return active_apps

    def isActive(self):
        return len(self.getActiveApps()) > 0

Thank you so much! This seems to be literally the only way to get camera status. Sucks that there isn't a better way