SDL_OpenCamera - Man Page
Open a video recording device (a "camera").
Header File
Defined in SDL3/SDL_camera.h
Synopsis
#include "SDL3/SDL.h" SDL_Camera * SDL_OpenCamera(SDL_CameraID instance_id, const SDL_CameraSpec *spec);
Description
You can open the device with any reasonable spec, and if the hardware can't directly support it, it will convert data seamlessly to the requested format. This might incur overhead, including scaling of image data.
If you would rather accept whatever format the device offers, you can pass a NULL spec here and it will choose one for you (and you can use
SDL_Surface necessary).
You can call SDL_GetCameraFormat () to get the actual data format if passing a NULL spec here. You can see the exact specs a device can support without conversion with
SDL_GetCameraSupportedFormats ().
SDL will not attempt to emulate framerate; it will try to set the hardware to the rate closest to the requested speed, but it won't attempt to limit or duplicate frames artificially; call
SDL_GetCameraFormat () to see the actual framerate of the opened the device, and check your timestamps if this is crucial to your app!
Note that the camera is not usable until the user approves its use! On some platforms, the operating system will prompt the user to permit access to the camera, and they can choose Yes or No at that point. Until they do, the camera will not be usable. The app should either wait for an
SDL_EVENT_CAMERA_DEVICE_APPROVED
(or
SDL_EVENT_CAMERA_DEVICE_DENIED ) event, or poll SDL_GetCameraPermissionState () occasionally until it returns non-zero. On platforms that don't require explicit user approval (and perhaps in places where the user previously permitted access), the approval event might come immediately, but it might come seconds, minutes, or hours later!
Function Parameters
- instance_id
the camera device instance ID.
- spec
the desired format for data the device will provide. Can be NULL.
Return Value
( SDL_Camera
*) Returns an SDL_Camera
object or NULL on failure; call SDL_GetError () for more information.
Thread Safety
It is safe to call this function from any thread.
Availability
This function is available since SDL 3.2.0.
See Also
·(3), SDL_GetCameras(3), ·(3), SDL_GetCameraFormat(3)
Referenced By
SDL_CloseCamera(3), SDL_GetCameraFormat(3), SDL_GetCameraID(3), SDL_GetCameraPermissionState(3), SDL_GetCameras(3), SDL_GetCameraSupportedFormats(3).