SDL Wiki
(This is the documentation for SDL3, which is under heavy development and the API is changing! SDL2 is the current stable version!)

SDL_OpenCameraDevice

Open a video recording device (a "camera").

Header File

Defined in <SDL3/SDL_camera.h>

Syntax

SDL_Camera* SDL_OpenCameraDevice(SDL_CameraDeviceID instance_id, const SDL_CameraSpec *spec);

Function Parameters

SDL_CameraDeviceID instance_id the camera device instance ID.
const SDL_CameraSpec * spec the desired format for data the device will provide. Can be NULL.

Return Value

(SDL_Camera *) Returns device, or NULL on failure; call SDL_GetError() for more information.

Remarks

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's conversion/scaling functions directly if 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_GetCameraSupportedSpecs().

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_IsCameraApproved() 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!

Thread Safety

It is safe to call this function from any thread.

Version

This function is available since SDL 3.0.0.

See Also


CategoryAPI, CategoryAPIFunction, CategoryCamera


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