camera: Windows support, through the Media Foundation API!

VisualC/SDL/SDL.vcxproj

@@ -397,6 +397,7 @@
       <PrecompiledHeader Condition="'$(Configuration)|$(Platform)'=='Release|x64'">Create</PrecompiledHeader>
     </ClCompile>
     <ClCompile Include="..\..\src\camera\dummy\SDL_camera_dummy.c" />
+    <ClCompile Include="..\..\src\camera\mediafoundation\SDL_camera_mediafoundation.c" />
     <ClCompile Include="..\..\src\camera\SDL_camera.c" />
     <ClCompile Include="..\..\src\main\generic\SDL_sysmain_callbacks.c" />
     <ClCompile Include="..\..\src\main\SDL_main_callbacks.c" />

VisualC/SDL/SDL.vcxproj.filters

@@ -184,6 +184,9 @@
     <Filter Include="camera\dummy">
       <UniqueIdentifier>{0000fc2700d453b3c8d79fe81e1c0000}</UniqueIdentifier>
     </Filter>
+    <Filter Include="camera\mediafoundation">
+      <UniqueIdentifier>{0000fbfe2d21e4f451142e7d0e870000}</UniqueIdentifier>
+    </Filter>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\include\SDL3\SDL_begin_code.h">
@@ -856,6 +859,9 @@
     <ClCompile Include="..\..\src\camera\dummy\SDL_camera_dummy.c">
       <Filter>camera\dummy</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\camera\mediafoundation\SDL_camera_mediafoundation.c">
+      <Filter>camera\mediafoundation</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\camera\SDL_camera.c">
       <Filter>camera</Filter>
     </ClCompile>

Xcode/SDL/SDL.xcodeproj/project.pbxproj

@@ -499,6 +499,7 @@
 		F3FA5A242B59ACE000FEAD97 /* yuv_rgb_lsx.h in Headers */ = {isa = PBXBuildFile; fileRef = F3FA5A1B2B59ACE000FEAD97 /* yuv_rgb_lsx.h */; };
 		F3FA5A252B59ACE000FEAD97 /* yuv_rgb_common.h in Headers */ = {isa = PBXBuildFile; fileRef = F3FA5A1C2B59ACE000FEAD97 /* yuv_rgb_common.h */; };
 		FA73671D19A540EF004122E4 /* CoreVideo.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = FA73671C19A540EF004122E4 /* CoreVideo.framework */; platformFilters = (ios, maccatalyst, macos, tvos, watchos, ); };
+		00009F560664255CCB6C0000 /* SDL_camera_mediafoundation.c in Sources */ = {isa = PBXBuildFile; fileRef = 0000C61C247BAAAF757D0000 /* SDL_camera_mediafoundation.c */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -1027,6 +1028,7 @@
 		F59C710600D5CB5801000001 /* SDL.info */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = text; path = SDL.info; sourceTree = "<group>"; };
 		F5A2EF3900C6A39A01000001 /* BUGS.txt */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = text; name = BUGS.txt; path = ../../BUGS.txt; sourceTree = SOURCE_ROOT; };
 		FA73671C19A540EF004122E4 /* CoreVideo.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreVideo.framework; path = System/Library/Frameworks/CoreVideo.framework; sourceTree = SDKROOT; };
+		0000C61C247BAAAF757D0000 /* SDL_camera_mediafoundation.c */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.c; name = SDL_camera_mediafoundation.c; path = SDL_camera_mediafoundation.c; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -1068,6 +1070,7 @@
 				0000035D38C3899C7EFD0000 /* SDL_camera.c */,
 				00009003C7148E1126CA0000 /* SDL_camera_c.h */,
 				00005D3EB902478835E20000 /* SDL_syscamera.h */,
+				0000926F2501CA0BDD650000 /* mediafoundation */,
 			);
 			path = camera;
 			sourceTree = "<group>";
@@ -2175,6 +2178,14 @@
 			path = resources;
 			sourceTree = "<group>";
 		};
+		0000926F2501CA0BDD650000 /* mediafoundation */ = {
+			isa = PBXGroup;
+			children = (
+				0000C61C247BAAAF757D0000 /* SDL_camera_mediafoundation.c */,
+			);
+			path = mediafoundation;
+			sourceTree = "<group>";
+		};
 /* End PBXGroup section */
 
 /* Begin PBXHeadersBuildPhase section */
@@ -2754,6 +2765,7 @@
 				000098E9DAA43EF6FF7F0000 /* SDL_camera.c in Sources */,
 				00001B2471F503DD3C1B0000 /* SDL_camera_dummy.c in Sources */,
 				00002B20A48E055EB0350000 /* SDL_camera_coremedia.m in Sources */,
+				00009F560664255CCB6C0000 /* SDL_camera_mediafoundation.c in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

include/build_config/SDL_build_config.h.cmake

@@ -472,7 +472,8 @@
 #cmakedefine SDL_CAMERA_DRIVER_V4L2 @SDL_CAMERA_DRIVER_V4L2@
 #cmakedefine SDL_CAMERA_DRIVER_COREMEDIA @SDL_CAMERA_DRIVER_COREMEDIA@
 #cmakedefine SDL_CAMERA_DRIVER_ANDROID @SDL_CAMERA_DRIVER_ANDROID@
-#cmakedefine SDL_CAMERA_DRIVER_EMSCRIPTEN @SDL_CAMERA_DRIVER_EMSCRIPTEND@
+#cmakedefine SDL_CAMERA_DRIVER_EMSCRIPTEN @SDL_CAMERA_DRIVER_EMSCRIPTEN@
+#cmakedefine SDL_CAMERA_DRIVER_MEDIAFOUNDATION @SDL_CAMERA_DRIVER_MEDIAFOUNDATION@
 
 /* Enable misc subsystem */
 #cmakedefine SDL_MISC_DUMMY @SDL_MISC_DUMMY@

include/build_config/SDL_build_config_windows.h

@@ -311,7 +311,8 @@ typedef unsigned int uintptr_t;
 /* Enable filesystem support */
 #define SDL_FILESYSTEM_WINDOWS  1
 
-/* Enable the camera driver (src/camera/dummy/\*.c) */  /* !!! FIXME */
+/* Enable the camera driver */
-#define SDL_CAMERA_DRIVER_DUMMY  1
+#define SDL_CAMERA_DRIVER_MEDIAFOUNDATION 1
+#define SDL_CAMERA_DRIVER_DUMMY 1
 
 #endif /* SDL_build_config_windows_h_ */

src/camera/SDL_camera.c

@@ -43,6 +43,9 @@ static const CameraBootStrap *const bootstrap[] = {
 #ifdef SDL_CAMERA_DRIVER_EMSCRIPTEN
     &EMSCRIPTENCAMERA_bootstrap,
 #endif
+#ifdef SDL_CAMERA_DRIVER_MEDIAFOUNDATION
+    &MEDIAFOUNDATION_bootstrap,
+#endif
 #ifdef SDL_CAMERA_DRIVER_DUMMY
     &DUMMYCAMERA_bootstrap,
 #endif
@@ -70,6 +73,32 @@ const char *SDL_GetCurrentCameraDriver(void)
     return camera_driver.name;
 }
 
+int SDL_AddCameraFormat(CameraFormatAddData *data, Uint32 fmt, int w, int h, int interval_numerator, int interval_denominator)
+{
+    SDL_assert(data != NULL);
+    if (data->allocated_specs <= data->num_specs) {
+        const int newalloc = data->allocated_specs ? (data->allocated_specs * 2) : 16;
+        void *ptr = SDL_realloc(data->specs, sizeof (SDL_CameraSpec) * newalloc);
+        if (!ptr) {
+            return -1;
+        }
+        data->specs = (SDL_CameraSpec *) ptr;
+        data->allocated_specs = newalloc;
+    }
+
+    SDL_CameraSpec *spec = &data->specs[data->num_specs];
+    spec->format = fmt;
+    spec->width = w;
+    spec->height = h;
+    spec->interval_numerator = interval_numerator;
+    spec->interval_denominator = interval_denominator;
+
+    data->num_specs++;
+
+    return 0;
+}
+
+
 static void ClosePhysicalCameraDevice(SDL_CameraDevice *device)
 {
     if (!device) {
@@ -610,10 +639,13 @@ SDL_bool SDL_CameraThreadIterate(SDL_CameraDevice *device)
 
     if (rc == 1) {  // new frame acquired!
         #if DEBUG_CAMERA
-        SDL_Log("CAMERA: New frame available!");
+        SDL_Log("CAMERA: New frame available! pixels=%p pitch=%d", device->acquire_surface->pixels, device->acquire_surface->pitch);
         #endif
 
         if (device->drop_frames > 0) {
+            #if DEBUG_CAMERA
+            SDL_Log("CAMERA: Dropping an initial frame");
+            #endif
             device->drop_frames--;
             camera_driver.impl.ReleaseFrame(device, device->acquire_surface);
             device->acquire_surface->pixels = NULL;
@@ -662,9 +694,15 @@ SDL_bool SDL_CameraThreadIterate(SDL_CameraDevice *device)
     } else if (acquired) {  // we have a new frame, scale/convert if necessary and queue it for the app!
         SDL_assert(slist != NULL);
         if (!device->needs_scaling && !device->needs_conversion) {  // no conversion needed? Just move the pointer/pitch into the output surface.
+            #if DEBUG_CAMERA
+            SDL_Log("CAMERA: Frame is going through without conversion!");
+            #endif
             output_surface->pixels = acquired->pixels;
             output_surface->pitch = acquired->pitch;
         } else {  // convert/scale into a different surface.
+            #if DEBUG_CAMERA
+            SDL_Log("CAMERA: Frame is getting converted!");
+            #endif
             SDL_Surface *srcsurf = acquired;
             if (device->needs_scaling == -1) {  // downscaling? Do it first.  -1: downscale, 0: no scaling, 1: upscale
                 SDL_Surface *dstsurf = device->needs_conversion ? device->conversion_surface : output_surface;

src/camera/SDL_syscamera.h

@@ -58,6 +58,16 @@ extern void SDL_CameraThreadSetup(SDL_CameraDevice *device);
 extern SDL_bool SDL_CameraThreadIterate(SDL_CameraDevice *device);
 extern void SDL_CameraThreadShutdown(SDL_CameraDevice *device);
 
+// common utility functionality to gather up camera specs. Not required!
+typedef struct CameraFormatAddData
+{
+    SDL_CameraSpec *specs;
+    int num_specs;
+    int allocated_specs;
+} CameraFormatAddData;
+
+int SDL_AddCameraFormat(CameraFormatAddData *data, Uint32 fmt, int w, int h, int interval_numerator, int interval_denominator);
+
 typedef struct SurfaceList
 {
     SDL_Surface *surface;
@@ -189,5 +199,6 @@ extern CameraBootStrap V4L2_bootstrap;
 extern CameraBootStrap COREMEDIA_bootstrap;
 extern CameraBootStrap ANDROIDCAMERA_bootstrap;
 extern CameraBootStrap EMSCRIPTENCAMERA_bootstrap;
+extern CameraBootStrap MEDIAFOUNDATION_bootstrap;
 
 #endif // SDL_syscamera_h_

src/camera/dummy/SDL_camera_dummy.c

@@ -77,4 +77,4 @@ CameraBootStrap DUMMYCAMERA_bootstrap = {
     "dummy", "SDL dummy camera driver", DUMMYCAMERA_Init, SDL_TRUE
 };
 
-#endif
+#endif  // SDL_CAMERA_DRIVER_DUMMY

src/camera/emscripten/SDL_camera_emscripten.c

@@ -79,8 +79,6 @@ static int EMSCRIPTENCAMERA_AcquireFrame(SDL_CameraDevice *device, SDL_Surface *
 static void EMSCRIPTENCAMERA_ReleaseFrame(SDL_CameraDevice *device, SDL_Surface *frame)
 {
     SDL_free(frame->pixels);
-    frame->pixels = NULL;
-    frame->pitch = 0;
 }
 
 static void EMSCRIPTENCAMERA_CloseDevice(SDL_CameraDevice *device)

src/camera/v4l2/SDL_camera_v4l2.c

@@ -631,39 +631,7 @@ static SDL_bool FindV4L2CameraDeviceByBusInfoCallback(SDL_CameraDevice *device,
     return (SDL_strcmp(handle->bus_info, (const char *) userdata) == 0);
 }
 
-typedef struct FormatAddData
+static int AddCameraFormat(const int fd, CameraFormatAddData *data, Uint32 sdlfmt, Uint32 v4l2fmt, int w, int h)
-{
-    SDL_CameraSpec *specs;
-    int num_specs;
-    int allocated_specs;
-} FormatAddData;
-
-static int AddCameraCompleteFormat(FormatAddData *data, Uint32 fmt, int w, int h, int interval_numerator, int interval_denominator)
-{
-    SDL_assert(data != NULL);
-    if (data->allocated_specs <= data->num_specs) {
-        const int newalloc = data->allocated_specs ? (data->allocated_specs * 2) : 16;
-        void *ptr = SDL_realloc(data->specs, sizeof (SDL_CameraSpec) * newalloc);
-        if (!ptr) {
-            return -1;
-        }
-        data->specs = (SDL_CameraSpec *) ptr;
-        data->allocated_specs = newalloc;
-    }
-
-    SDL_CameraSpec *spec = &data->specs[data->num_specs];
-    spec->format = fmt;
-    spec->width = w;
-    spec->height = h;
-    spec->interval_numerator = interval_numerator;
-    spec->interval_denominator = interval_denominator;
-
-    data->num_specs++;
-
-    return 0;
-}
-
-static int AddCameraFormat(const int fd, FormatAddData *data, Uint32 sdlfmt, Uint32 v4l2fmt, int w, int h)
 {
     struct v4l2_frmivalenum frmivalenum;
     SDL_zero(frmivalenum);
@@ -679,7 +647,7 @@ static int AddCameraFormat(const int fd, FormatAddData *data, Uint32 sdlfmt, Uin
             const float fps = (float) denominator / (float) numerator;
             SDL_Log("CAMERA:       * Has discrete frame interval (%d / %d), fps=%f", numerator, denominator, fps);
             #endif
-            if (AddCameraCompleteFormat(data, sdlfmt, w, h, numerator, denominator) == -1) {
+            if (SDL_AddCameraFormat(data, sdlfmt, w, h, numerator, denominator) == -1) {
                 return -1;  // Probably out of memory; we'll go with what we have, if anything.
             }
             frmivalenum.index++;  // set up for the next one.
@@ -691,7 +659,7 @@ static int AddCameraFormat(const int fd, FormatAddData *data, Uint32 sdlfmt, Uin
                 const float fps = (float) d / (float) n;
                 SDL_Log("CAMERA:       * Has %s frame interval (%d / %d), fps=%f", (frmivalenum.type == V4L2_FRMIVAL_TYPE_STEPWISE) ? "stepwise" : "continuous", n, d, fps);
                 #endif
-                if (AddCameraCompleteFormat(data, sdlfmt, w, h, n, d) == -1) {
+                if (SDL_AddCameraFormat(data, sdlfmt, w, h, n, d) == -1) {
                     return -1;  // Probably out of memory; we'll go with what we have, if anything.
                 }
                 d += (int) frmivalenum.stepwise.step.denominator;
@@ -739,7 +707,7 @@ static void MaybeAddDevice(const char *path)
     SDL_Log("CAMERA: V4L2 camera path='%s' bus_info='%s' name='%s'", path, (const char *) vcap.bus_info, vcap.card);
     #endif
 
-    FormatAddData add_data;
+    CameraFormatAddData add_data;
     SDL_zero(add_data);
 
     struct v4l2_fmtdesc fmtdesc;
@@ -911,5 +879,5 @@ CameraBootStrap V4L2_bootstrap = {
     "v4l2", "SDL Video4Linux2 camera driver", V4L2_Init, SDL_FALSE
 };
 
-#endif // SDL_CAMERA_V4L2
+#endif // SDL_CAMERA_DRIVER_V4L2