Test app to confirm whether or not app can get USB permission for UVC device with verious target SDK version.
Copyright (c) 2019 saki t_saki@serenegiant.com
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As documents on Android Developers shows, app that use USB WebCam(UVC device) needs CAMERA permission if it runs on Android 9 and later.
But even if app has CAMERA permission, app can't get USB permission to access UVC device on Android 10 if target SDK version is 28 and later.
OK in following tables means app could get USB permission NG means app could't get permission.
targe SDK version <= 27
| UVC, has CAMERA permission | UVC, has no CAMERA permission | other USB device | |
|---|---|---|---|
| Android <= 8 | OK | OK | OK |
| Android 9 | OK | NG(expected) | OK |
| Android 10 | OK | NG(expected) | OK |
targe SDK version >= 28
| UVC, has CAMERA permission | UVC, has no CAMERA permission | other USB device | |
|---|---|---|---|
| Android < 8 | OK | OK | OK |
| Android 9 | OK | NG(expected) | OK |
| Android 10 | NG (unexpected) | NG(expected) | OK |
Test devices:
When app request permission, or when user give permission from system permission dialog, Android output error message on logCat regardless app has CAMERA permission or not.
UsbUserSettingsManager: Camera permission required for USB video class devices