06-20 21:04:15.902 16876 16876 F DEBUG   :       #08 pc 00003ceb  /vendor/lib/hw/[email protected] (virtual thunk to android::hardware::camera::provider::V2_4::implementation::CameraProvider<android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4>::~CameraProvider()+75) (BuildId: 61f370932646d54b04cc68702a95f8fa)
06-20 21:04:15.902 16876 16876 F DEBUG   :       #12 pc 00001aee  /vendor/bin/hw/[email protected] (BuildId: e02058b00fe96b518e5b0b850ff2870c)
06-20 21:04:15.902 16876 16876 F DEBUG   :       #13 pc 00001993  /vendor/bin/hw/[email protected] (main+179) (BuildId: e02058b00fe96b518e5b0b850ff2870c)
06-20 21:04:20.913 16884 16884 I [email protected]: [email protected] legacy service is starting.
06-20 21:04:20.913 16883 16883 I [email protected]: External camera provider service is starting.
06-20 21:04:20.925 16884 16884 E [email protected]: Could not load camera HAL module: -2 (No such file or directory)
06-20 21:04:20.925 16884 16884 E [email protected]: getProviderImpl: camera provider init failed!
06-20 21:04:20.925 16883 16883 I [email protected]: loadFromCfg: load external camera config succeed!
06-20 21:04:20.925 16883 16883 I [email protected]: loadFromCfg: device 0 will be ignored by external camera provider
06-20 21:04:20.926 16883 16883 I [email protected]: loadFromCfg: external camera cfg loaded: maxJpgBufSize 3145728, num video buffers 4, num still buffers 2, orientation 0
06-20 21:04:20.926 16883 16883 E HidlServiceManagement: Service [email protected]::ICameraProvider/external/0 must be in VINTF manifest in order to register/get.
06-20 21:04:20.926 16883 16883 E LegacySupport: Could not register service [email protected]::ICameraProvider/external/0 (-2147483648).
06-20 21:04:20.928 16884 16884 E LegacySupport: Could not get passthrough implementation for [email protected]::ICameraProvider/legacy/0.
06-20 21:04:20.934 16888 16888 F DEBUG   : pid: 16883, tid: 16883, name: android.hardwar  >>> /vendor/bin/hw/[email protected] <<<
06-20 21:04:20.937 16888 16888 F DEBUG   :       #06 pc 0000e293  /vendor/lib/[email protected] (android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4::HotplugThread::~HotplugThread()+99) (BuildId: c893ccbbe5cfdc71842b89443e84b793)
06-20 21:04:20.937 16888 16888 F DEBUG   :       #07 pc 0000e12d  /vendor/lib/[email protected] (android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4::~ExternalCameraProviderImpl_2_4()+45) (BuildId: c893ccbbe5cfdc71842b89443e84b793)
06-20 21:04:20.937 16888 16888 F DEBUG   :       #08 pc 00003ceb  /vendor/lib/hw/[email protected] (virtual thunk to android::hardware::camera::provider::V2_4::implementation::CameraProvider<android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4>::~CameraProvider()+75) (BuildId: 61f370932646d54b04cc68702a95f8fa)
06-20 21:04:20.937 16888 16888 F DEBUG   :       #12 pc 00001aee  /vendor/bin/hw/[email protected] (BuildId: e02058b00fe96b518e5b0b850ff2870c)
06-20 21:04:20.937 16888 16888 F DEBUG   :       #13 pc 00001993  /vendor/bin/hw/[email protected] (main+179) (BuildId: e02058b00fe96b518e5b0b850ff2870c)
06-20 21:04:24.573   150   281 E CameraService: cameraIdIntToStrLocked: input id 0 invalid: valid range  (0, 0)
06-20 21:04:24.573   150   281 I CameraService: CameraService::connect call (PID -1 "com.whatsapp", camera ID ) for HAL version default and Camera API version 1
06-20 21:04:24.573   150   281 E CameraService: shouldRejectSystemCameraConnection: Invalid camera id ,
06-20 21:04:24.573   150   281 W CameraService: Attempting to connect to system-only camera id , connection rejected
06-20 21:04:24.573  1455 16941 W CameraBase: An error occurred while connecting to camera 0: Status(-8, EX_SERVICE_SPECIFIC): '4: validateClientPermissionsLocked:1158: No camera device with ID "" isavailable'
06-20 21:04:25.914 17093 17093 I [email protected]: External camera provider service is starting.
06-20 21:04:25.920 17094 17094 I [email protected]: [email protected] legacy service is starting.
06-20 21:04:25.932 17093 17093 I [email protected]: loadFromCfg: load external camera config succeed!
06-20 21:04:25.932 17093 17093 I [email protected]: loadFromCfg: device 0 will be ignored by external camera provider
06-20 21:04:25.932 17093 17093 I [email protected]: loadFromCfg: external camera cfg loaded: maxJpgBufSize 3145728, num video buffers 4, num still buffers 2, orientation 0
06-20 21:04:25.932 17093 17093 E HidlServiceManagement: Service [email protected]::ICameraProvider/external/0 must be in VINTF manifest in order to register/get.
06-20 21:04:25.932 17094 17094 E [email protected]: Could not load camera HAL module: -2 (No such file or directory)
06-20 21:04:25.933 17093 17093 E LegacySupport: Could not register service [email protected]::ICameraProvider/external/0 (-2147483648).
06-20 21:04:25.933 17094 17094 E [email protected]: getProviderImpl: camera provider init failed!
06-20 21:04:25.935 17094 17094 E LegacySupport: Could not get passthrough implementation for [email protected]::ICameraProvider/legacy/0.
06-20 21:04:25.942 17101 17101 F DEBUG   : pid: 17093, tid: 17093, name: android.hardwar  >>> /vendor/bin/hw/[email protected] <<<
06-20 21:04:25.945 17101 17101 F DEBUG   :       #06 pc 0000e293  /vendor/lib/[email protected] (android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4::HotplugThread::~HotplugThread()+99) (BuildId: c893ccbbe5cfdc71842b89443e84b793)
06-20 21:04:25.945 17101 17101 F DEBUG   :       #07 pc 0000e12d  /vendor/lib/[email protected] (android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4::~ExternalCameraProviderImpl_2_4()+45) (BuildId: c893ccbbe5cfdc71842b89443e84b793)
06-20 21:04:25.945 17101 17101 F DEBUG   :       #08 pc 00003ceb  /vendor/lib/hw/[email protected] (virtual thunk to android::hardware::camera::provider::V2_4::implementation::CameraProvider<android::hardware::camera::provider::V2_4::implementation::ExternalCameraProviderImpl_2_4>::~CameraProvider()+75) (BuildId: 61f370932646d54b04cc68702a95f8fa)
06-20 21:04:25.945 17101 17101 F DEBUG   :       #12 pc 00001aee  /vendor/bin/hw/[email protected] (BuildId: e02058b00fe96b518e5b0b850ff2870c)
06-20 21:04:25.945 17101 17101 F DEBUG   :       #13 pc 00001993  /vendor/bin/hw/[email protected] (main+179) (BuildId: e02058b00fe96b518e5b0b850ff2870c)

I'd like to know how to change the default camera on Android to a USB camera, I'd like to use my webcam to authenticate QR codes, but with emulator, the camera doesn't start, I can only get video through a USB camera (v4l2) Hello and good afternoon, @artbreguez
Welcome to XDA. I hope you'll always find and get the support you require.
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