--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SDL3/SDL_camera.h	Mon Jan 05 02:15:46 2026 -0500
@@ -0,0 +1,535 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+/**
+ * # CategoryCamera
+ *
+ * Video capture for the SDL library.
+ *
+ * This API lets apps read input from video sources, like webcams. Camera
+ * devices can be enumerated, queried, and opened. Once opened, it will
+ * provide SDL_Surface objects as new frames of video come in. These surfaces
+ * can be uploaded to an SDL_Texture or processed as pixels in memory.
+ *
+ * Several platforms will alert the user if an app tries to access a camera,
+ * and some will present a UI asking the user if your application should be
+ * allowed to obtain images at all, which they can deny. A successfully opened
+ * camera will not provide images until permission is granted. Applications,
+ * after opening a camera device, can see if they were granted access by
+ * either polling with the SDL_GetCameraPermissionState() function, or waiting
+ * for an SDL_EVENT_CAMERA_DEVICE_APPROVED or SDL_EVENT_CAMERA_DEVICE_DENIED
+ * event. Platforms that don't have any user approval process will report
+ * approval immediately.
+ *
+ * Note that SDL cameras only provide video as individual frames; they will
+ * not provide full-motion video encoded in a movie file format, although an
+ * app is free to encode the acquired frames into any format it likes. It also
+ * does not provide audio from the camera hardware through this API; not only
+ * do many webcams not have microphones at all, many people--from streamers to
+ * people on Zoom calls--will want to use a separate microphone regardless of
+ * the camera. In any case, recorded audio will be available through SDL's
+ * audio API no matter what hardware provides the microphone.
+ *
+ * ## Camera gotchas
+ *
+ * Consumer-level camera hardware tends to take a little while to warm up,
+ * once the device has been opened. Generally most camera apps have some sort
+ * of UI to take a picture (a button to snap a pic while a preview is showing,
+ * some sort of multi-second countdown for the user to pose, like a photo
+ * booth), which puts control in the users' hands, or they are intended to
+ * stay on for long times (Pokemon Go, etc).
+ *
+ * It's not uncommon that a newly-opened camera will provide a couple of
+ * completely black frames, maybe followed by some under-exposed images. If
+ * taking a single frame automatically, or recording video from a camera's
+ * input without the user initiating it from a preview, it could be wise to
+ * drop the first several frames (if not the first several _seconds_ worth of
+ * frames!) before using images from a camera.
+ */
+
+#ifndef SDL_camera_h_
+#define SDL_camera_h_
+
+#include <SDL3/SDL_stdinc.h>
+#include <SDL3/SDL_error.h>
+#include <SDL3/SDL_pixels.h>
+#include <SDL3/SDL_properties.h>
+#include <SDL3/SDL_surface.h>
+
+#include <SDL3/SDL_begin_code.h>
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * This is a unique ID for a camera device for the time it is connected to the
+ * system, and is never reused for the lifetime of the application.
+ *
+ * If the device is disconnected and reconnected, it will get a new ID.
+ *
+ * The value 0 is an invalid ID.
+ *
+ * \since This datatype is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameras
+ */
+typedef Uint32 SDL_CameraID;
+
+/**
+ * The opaque structure used to identify an opened SDL camera.
+ *
+ * \since This struct is available since SDL 3.2.0.
+ */
+typedef struct SDL_Camera SDL_Camera;
+
+/**
+ * The details of an output format for a camera device.
+ *
+ * Cameras often support multiple formats; each one will be encapsulated in
+ * this struct.
+ *
+ * \since This struct is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameraSupportedFormats
+ * \sa SDL_GetCameraFormat
+ */
+typedef struct SDL_CameraSpec
+{
+    SDL_PixelFormat format;     /**< Frame format */
+    SDL_Colorspace colorspace;  /**< Frame colorspace */
+    int width;                  /**< Frame width */
+    int height;                 /**< Frame height */
+    int framerate_numerator;     /**< Frame rate numerator ((num / denom) == FPS, (denom / num) == duration in seconds) */
+    int framerate_denominator;   /**< Frame rate denominator ((num / denom) == FPS, (denom / num) == duration in seconds) */
+} SDL_CameraSpec;
+
+/**
+ * The position of camera in relation to system device.
+ *
+ * \since This enum is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameraPosition
+ */
+typedef enum SDL_CameraPosition
+{
+    SDL_CAMERA_POSITION_UNKNOWN,
+    SDL_CAMERA_POSITION_FRONT_FACING,
+    SDL_CAMERA_POSITION_BACK_FACING
+} SDL_CameraPosition;
+
+/**
+ * The current state of a request for camera access.
+ *
+ * \since This enum is available since SDL 3.4.0.
+ *
+ * \sa SDL_GetCameraPermissionState
+ */
+typedef enum SDL_CameraPermissionState
+{
+    SDL_CAMERA_PERMISSION_STATE_DENIED = -1,
+    SDL_CAMERA_PERMISSION_STATE_PENDING,
+    SDL_CAMERA_PERMISSION_STATE_APPROVED,
+} SDL_CameraPermissionState;
+
+
+/**
+ * Use this function to get the number of built-in camera drivers.
+ *
+ * This function returns a hardcoded number. This never returns a negative
+ * value; if there are no drivers compiled into this build of SDL, this
+ * function returns zero. The presence of a driver in this list does not mean
+ * it will function, it just means SDL is capable of interacting with that
+ * interface. For example, a build of SDL might have v4l2 support, but if
+ * there's no kernel support available, SDL's v4l2 driver would fail if used.
+ *
+ * By default, SDL tries all drivers, in its preferred order, until one is
+ * found to be usable.
+ *
+ * \returns the number of built-in camera drivers.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameraDriver
+ */
+extern SDL_DECLSPEC int SDLCALL SDL_GetNumCameraDrivers(void);
+
+/**
+ * Use this function to get the name of a built in camera driver.
+ *
+ * The list of camera drivers is given in the order that they are normally
+ * initialized by default; the drivers that seem more reasonable to choose
+ * first (as far as the SDL developers believe) are earlier in the list.
+ *
+ * The names of drivers are all simple, low-ASCII identifiers, like "v4l2",
+ * "coremedia" or "android". These never have Unicode characters, and are not
+ * meant to be proper names.
+ *
+ * \param index the index of the camera driver; the value ranges from 0 to
+ *              SDL_GetNumCameraDrivers() - 1.
+ * \returns the name of the camera driver at the requested index, or NULL if
+ *          an invalid index was specified.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetNumCameraDrivers
+ */
+extern SDL_DECLSPEC const char * SDLCALL SDL_GetCameraDriver(int index);
+
+/**
+ * Get the name of the current camera driver.
+ *
+ * The names of drivers are all simple, low-ASCII identifiers, like "v4l2",
+ * "coremedia" or "android". These never have Unicode characters, and are not
+ * meant to be proper names.
+ *
+ * \returns the name of the current camera driver or NULL if no driver has
+ *          been initialized.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC const char * SDLCALL SDL_GetCurrentCameraDriver(void);
+
+/**
+ * Get a list of currently connected camera devices.
+ *
+ * \param count a pointer filled in with the number of cameras returned, may
+ *              be NULL.
+ * \returns a 0 terminated array of camera instance IDs or NULL on failure;
+ *          call SDL_GetError() for more information. This should be freed
+ *          with SDL_free() when it is no longer needed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_OpenCamera
+ */
+extern SDL_DECLSPEC SDL_CameraID * SDLCALL SDL_GetCameras(int *count);
+
+/**
+ * Get the list of native formats/sizes a camera supports.
+ *
+ * This returns a list of all formats and frame sizes that a specific camera
+ * can offer. This is useful if your app can accept a variety of image formats
+ * and sizes and so want to find the optimal spec that doesn't require
+ * conversion.
+ *
+ * This function isn't strictly required; if you call SDL_OpenCamera with a
+ * NULL spec, SDL will choose a native format for you, and if you instead
+ * specify a desired format, it will transparently convert to the requested
+ * format on your behalf.
+ *
+ * If `count` is not NULL, it will be filled with the number of elements in
+ * the returned array.
+ *
+ * Note that it's legal for a camera to supply an empty list. This is what
+ * will happen on Emscripten builds, since that platform won't tell _anything_
+ * about available cameras until you've opened one, and won't even tell if
+ * there _is_ a camera until the user has given you permission to check
+ * through a scary warning popup.
+ *
+ * \param instance_id the camera device instance ID.
+ * \param count a pointer filled in with the number of elements in the list,
+ *              may be NULL.
+ * \returns a NULL terminated array of pointers to SDL_CameraSpec or NULL on
+ *          failure; call SDL_GetError() for more information. This is a
+ *          single allocation that should be freed with SDL_free() when it is
+ *          no longer needed.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameras
+ * \sa SDL_OpenCamera
+ */
+extern SDL_DECLSPEC SDL_CameraSpec ** SDLCALL SDL_GetCameraSupportedFormats(SDL_CameraID instance_id, int *count);
+
+/**
+ * Get the human-readable device name for a camera.
+ *
+ * \param instance_id the camera device instance ID.
+ * \returns a human-readable device name or NULL on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameras
+ */
+extern SDL_DECLSPEC const char * SDLCALL SDL_GetCameraName(SDL_CameraID instance_id);
+
+/**
+ * Get the position of the camera in relation to the system.
+ *
+ * Most platforms will report UNKNOWN, but mobile devices, like phones, can
+ * often make a distinction between cameras on the front of the device (that
+ * points towards the user, for taking "selfies") and cameras on the back (for
+ * filming in the direction the user is facing).
+ *
+ * \param instance_id the camera device instance ID.
+ * \returns the position of the camera on the system hardware.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameras
+ */
+extern SDL_DECLSPEC SDL_CameraPosition SDLCALL SDL_GetCameraPosition(SDL_CameraID instance_id);
+
+/**
+ * Open a video recording device (a "camera").
+ *
+ * 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_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!
+ *
+ * \param instance_id the camera device instance ID.
+ * \param spec the desired format for data the device will provide. Can be
+ *             NULL.
+ * \returns an SDL_Camera object or NULL on failure; call SDL_GetError() for
+ *          more information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_GetCameras
+ * \sa SDL_GetCameraFormat
+ */
+extern SDL_DECLSPEC SDL_Camera * SDLCALL SDL_OpenCamera(SDL_CameraID instance_id, const SDL_CameraSpec *spec);
+
+/**
+ * Query if camera access has been approved by the user.
+ *
+ * Cameras will not function between when the device is opened by the app and
+ * when the user permits access to the hardware. On some platforms, this
+ * presents as a popup dialog where the user has to explicitly approve access;
+ * on others the approval might be implicit and not alert the user at all.
+ *
+ * This function can be used to check the status of that approval. It will
+ * return SDL_CAMERA_PERMISSION_STATE_PENDING if waiting for user response,
+ * SDL_CAMERA_PERMISSION_STATE_APPROVED if the camera is approved for use, and
+ * SDL_CAMERA_PERMISSION_STATE_DENIED if the user denied access.
+ *
+ * Instead of polling with this function, you can wait for a
+ * SDL_EVENT_CAMERA_DEVICE_APPROVED (or SDL_EVENT_CAMERA_DEVICE_DENIED) event
+ * in the standard SDL event loop, which is guaranteed to be sent once when
+ * permission to use the camera is decided.
+ *
+ * If a camera is declined, there's nothing to be done but call
+ * SDL_CloseCamera() to dispose of it.
+ *
+ * \param camera the opened camera device to query.
+ * \returns an SDL_CameraPermissionState value indicating if access is
+ *          granted, or `SDL_CAMERA_PERMISSION_STATE_PENDING` if the decision
+ *          is still pending.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_OpenCamera
+ * \sa SDL_CloseCamera
+ */
+extern SDL_DECLSPEC SDL_CameraPermissionState SDLCALL SDL_GetCameraPermissionState(SDL_Camera *camera);
+
+/**
+ * Get the instance ID of an opened camera.
+ *
+ * \param camera an SDL_Camera to query.
+ * \returns the instance ID of the specified camera on success or 0 on
+ *          failure; call SDL_GetError() for more information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_OpenCamera
+ */
+extern SDL_DECLSPEC SDL_CameraID SDLCALL SDL_GetCameraID(SDL_Camera *camera);
+
+/**
+ * Get the properties associated with an opened camera.
+ *
+ * \param camera the SDL_Camera obtained from SDL_OpenCamera().
+ * \returns a valid property ID on success or 0 on failure; call
+ *          SDL_GetError() for more information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ */
+extern SDL_DECLSPEC SDL_PropertiesID SDLCALL SDL_GetCameraProperties(SDL_Camera *camera);
+
+/**
+ * Get the spec that a camera is using when generating images.
+ *
+ * Note that this might not be the native format of the hardware, as SDL might
+ * be converting to this format behind the scenes.
+ *
+ * If the system is waiting for the user to approve access to the camera, as
+ * some platforms require, this will return false, but this isn't necessarily
+ * a fatal error; you 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.
+ *
+ * \param camera opened camera device.
+ * \param spec the SDL_CameraSpec to be initialized by this function.
+ * \returns true on success or false on failure; call SDL_GetError() for more
+ *          information.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_OpenCamera
+ */
+extern SDL_DECLSPEC bool SDLCALL SDL_GetCameraFormat(SDL_Camera *camera, SDL_CameraSpec *spec);
+
+/**
+ * Acquire a frame.
+ *
+ * The frame is a memory pointer to the image data, whose size and format are
+ * given by the spec requested when opening the device.
+ *
+ * This is a non blocking API. If there is a frame available, a non-NULL
+ * surface is returned, and timestampNS will be filled with a non-zero value.
+ *
+ * Note that an error case can also return NULL, but a NULL by itself is
+ * normal and just signifies that a new frame is not yet available. Note that
+ * even if a camera device fails outright (a USB camera is unplugged while in
+ * use, etc), SDL will send an event separately to notify the app, but
+ * continue to provide blank frames at ongoing intervals until
+ * SDL_CloseCamera() is called, so real failure here is almost always an out
+ * of memory condition.
+ *
+ * After use, the frame should be released with SDL_ReleaseCameraFrame(). If
+ * you don't do this, the system may stop providing more video!
+ *
+ * Do not call SDL_DestroySurface() on the returned surface! It must be given
+ * back to the camera subsystem with SDL_ReleaseCameraFrame!
+ *
+ * If the system is waiting for the user to approve access to the camera, as
+ * some platforms require, this will return NULL (no frames available); you
+ * 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.
+ *
+ * \param camera opened camera device.
+ * \param timestampNS a pointer filled in with the frame's timestamp, or 0 on
+ *                    error. Can be NULL.
+ * \returns a new frame of video on success, NULL if none is currently
+ *          available.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_ReleaseCameraFrame
+ */
+extern SDL_DECLSPEC SDL_Surface * SDLCALL SDL_AcquireCameraFrame(SDL_Camera *camera, Uint64 *timestampNS);
+
+/**
+ * Release a frame of video acquired from a camera.
+ *
+ * Let the back-end re-use the internal buffer for camera.
+ *
+ * This function _must_ be called only on surface objects returned by
+ * SDL_AcquireCameraFrame(). This function should be called as quickly as
+ * possible after acquisition, as SDL keeps a small FIFO queue of surfaces for
+ * video frames; if surfaces aren't released in a timely manner, SDL may drop
+ * upcoming video frames from the camera.
+ *
+ * If the app needs to keep the surface for a significant time, they should
+ * make a copy of it and release the original.
+ *
+ * The app should not use the surface again after calling this function;
+ * assume the surface is freed and the pointer is invalid.
+ *
+ * \param camera opened camera device.
+ * \param frame the video frame surface to release.
+ *
+ * \threadsafety It is safe to call this function from any thread.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_AcquireCameraFrame
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_ReleaseCameraFrame(SDL_Camera *camera, SDL_Surface *frame);
+
+/**
+ * Use this function to shut down camera processing and close the camera
+ * device.
+ *
+ * \param camera opened camera device.
+ *
+ * \threadsafety It is safe to call this function from any thread, but no
+ *               thread may reference `device` once this function is called.
+ *
+ * \since This function is available since SDL 3.2.0.
+ *
+ * \sa SDL_OpenCamera
+ */
+extern SDL_DECLSPEC void SDLCALL SDL_CloseCamera(SDL_Camera *camera);
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include <SDL3/SDL_close_code.h>
+
+#endif /* SDL_camera_h_ */