![]() The firmware must provide the _PLD method and set the Panel field (bits 69:67) to the appropriate value for the panel on which the camera is mounted. This applies to any camera device that is built into the chassis of the system and has mechanically fixed direction. ![]() In accordance with certification requirement, the _PLD value that indicates the camera's location must be provided in the ACPI (Advanced Configuration and Power Interface) table. How to provide physical location using _PLD info in the ACPI table For more info, see DeviceOverrides Registry Key. Otherwise, override the removable flag by using the DeviceOverrides registry key. If the device can expose information on the physical device location in ACPI tables, the correct grouping can be specified in the ACPI layer by including _PLD information in the tables and modifying the UserVisible flag in the ACPI table, as described in Multifunction Device Support and Device Container Groupings. ![]() The way to implement this requirement depends on the bus type of the internal camera. In other words, the internal camera should not be displayed in Devices and Printers and must be consolidated into the PC container. In accordance with certification requirement, also known as SYSFUND-0200, the internal camera device nodes must be grouped under the PC device container. How to group the camera into the computers device container If the app rotates the preview, the degree of rotation differs depending on the position of the camera. If the camera is facing away from the user, the app does not need to mirror the video. To do this, the app will flip the left and right sides of the preview, so that the preview mirrors the video. If the camera is facing the user, the preview should look as if the user is looking into a mirror. UWP apps use the physical location to determine how to mirror or rotate the video preview. For example, a chat application will default to using the front camera that faces the user when the app starts up. UWP apps use the physical location to determine which camera to use if multiple cameras are present. Windows needs to know the physical location of internal cameras for the following reasons: Why Windows requires the physical location cameras The firmware must provide physical location info, by using the _PLD information in ACPI tables to indicate the location and orientation of the camera. A camera must be grouped into the computer's device container to expose its physical location to apps, because devices external to the computer container aren't assumed to have a mechanically fixed direction. The camera must be grouped into the computer's device container, which contains the device functions located physically inside the computer. The following two Windows Hardware Certification Requirements, which allow Windows to recognize a camera's location, are required: This physical location info indicates which direction the camera is facing, such as front or back, so that apps for using the camera in Windows 8.1 function correctly. Systems with built-in cameras with mechanically fixed direction must report the physical location of the cameras. ![]() To learn more about UWP device apps in general, see Meet UWP device apps. It also describes how to set the Model ID so that the camera works with UWP device apps. It describes how to identify the physical location of built-in cameras so that they work correctly with UWP apps. This topic provides info about supporting internal cameras on systems in Windows 8.1.
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