Video backend

CMakeLists.txt

@@ -49,6 +49,10 @@ set(APP_SOURCES
 	"${APP_DIR}/videoio/decklink/DeckLinkSession.h"
 	"${APP_DIR}/videoio/decklink/DeckLinkVideoIOFormat.cpp"
 	"${APP_DIR}/videoio/decklink/DeckLinkVideoIOFormat.h"
+	"${APP_DIR}/videoio/VideoIOBackendFactory.cpp"
+	"${APP_DIR}/videoio/VideoIOBackendFactory.h"
+	"${APP_DIR}/videoio/VideoIOConfig.cpp"
+	"${APP_DIR}/videoio/VideoIOConfig.h"
 	"${APP_DIR}/gl/renderer/GLExtensions.cpp"
 	"${APP_DIR}/gl/renderer/GLExtensions.h"
 	"${APP_DIR}/gl/shader/GlobalParamsBuffer.cpp"
@@ -204,6 +208,35 @@ endif()
 
 add_test(NAME RuntimeParameterUtilsTests COMMAND RuntimeParameterUtilsTests)
 
+add_executable(RuntimeHostVideoIOStateTests
+	"${APP_DIR}/runtime/RuntimeHost.cpp"
+	"${APP_DIR}/runtime/RuntimeClock.cpp"
+	"${APP_DIR}/runtime/RuntimeJson.cpp"
+	"${APP_DIR}/runtime/RuntimeParameterUtils.cpp"
+	"${APP_DIR}/shader/ShaderCompiler.cpp"
+	"${APP_DIR}/shader/ShaderPackageRegistry.cpp"
+	"${APP_DIR}/videoio/VideoIOConfig.cpp"
+	"${CMAKE_CURRENT_SOURCE_DIR}/tests/RuntimeHostVideoIOStateTests.cpp"
+)
+
+target_include_directories(RuntimeHostVideoIOStateTests PRIVATE
+	"${APP_DIR}"
+	"${APP_DIR}/platform"
+	"${APP_DIR}/runtime"
+	"${APP_DIR}/shader"
+	"${APP_DIR}/videoio"
+)
+
+target_link_libraries(RuntimeHostVideoIOStateTests PRIVATE
+	Advapi32
+)
+
+if(MSVC)
+	target_compile_options(RuntimeHostVideoIOStateTests PRIVATE /W3)
+endif()
+
+add_test(NAME RuntimeHostVideoIOStateTests COMMAND RuntimeHostVideoIOStateTests)
+
 add_executable(Std140BufferTests
 	"${CMAKE_CURRENT_SOURCE_DIR}/tests/Std140BufferTests.cpp"
 )
@@ -318,6 +351,7 @@ endif()
 add_test(NAME VideoPlayoutSchedulerTests COMMAND VideoPlayoutSchedulerTests)
 
 add_executable(VideoIODeviceFakeTests
+	"${APP_DIR}/videoio/VideoIOConfig.cpp"
 	"${APP_DIR}/videoio/VideoIOFormat.cpp"
 	"${CMAKE_CURRENT_SOURCE_DIR}/tests/VideoIODeviceFakeTests.cpp"
 )
@@ -334,6 +368,43 @@ endif()
 
 add_test(NAME VideoIODeviceFakeTests COMMAND VideoIODeviceFakeTests)
 
+add_executable(VideoIOBackendFactoryTests
+	"${APP_DIR}/videoio/decklink/DeckLinkAPI_i.c"
+	"${APP_DIR}/videoio/decklink/DeckLinkSession.cpp"
+	"${APP_DIR}/videoio/decklink/DeckLinkSession.h"
+	"${APP_DIR}/videoio/decklink/DeckLinkDisplayMode.cpp"
+	"${APP_DIR}/videoio/decklink/DeckLinkDisplayMode.h"
+	"${APP_DIR}/videoio/decklink/DeckLinkVideoIOFormat.cpp"
+	"${APP_DIR}/videoio/decklink/DeckLinkVideoIOFormat.h"
+	"${APP_DIR}/videoio/decklink/DeckLinkFrameTransfer.cpp"
+	"${APP_DIR}/videoio/decklink/DeckLinkFrameTransfer.h"
+	"${APP_DIR}/videoio/VideoIOBackendFactory.cpp"
+	"${APP_DIR}/videoio/VideoIOBackendFactory.h"
+	"${APP_DIR}/videoio/VideoIOConfig.cpp"
+	"${APP_DIR}/videoio/VideoIOConfig.h"
+	"${APP_DIR}/videoio/VideoIOFormat.cpp"
+	"${APP_DIR}/videoio/VideoPlayoutScheduler.cpp"
+	"${APP_DIR}/videoio/VideoPlayoutScheduler.h"
+	"${CMAKE_CURRENT_SOURCE_DIR}/tests/VideoIOBackendFactoryTests.cpp"
+)
+
+target_include_directories(VideoIOBackendFactoryTests PRIVATE
+	"${APP_DIR}"
+	"${APP_DIR}/gl/renderer"
+	"${APP_DIR}/videoio"
+	"${APP_DIR}/videoio/decklink"
+)
+
+target_link_libraries(VideoIOBackendFactoryTests PRIVATE
+	Ole32
+)
+
+if(MSVC)
+	target_compile_options(VideoIOBackendFactoryTests PRIVATE /W3)
+endif()
+
+add_test(NAME VideoIOBackendFactoryTests COMMAND VideoIOBackendFactoryTests)
+
 install(TARGETS LoopThroughWithOpenGLCompositing
 	RUNTIME DESTINATION "."
 )

apps/LoopThroughWithOpenGLCompositing/LoopThroughWithOpenGLCompositing.cpp

@@ -412,10 +412,10 @@ LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
 				break;
 			}
 
-			// Setup OpenGL and DeckLink capture and playout object
+			// Setup OpenGL and video I/O capture/playout object
 			pOpenGLComposite = new OpenGLComposite(hWnd, hDC, hRC);
 
-			if (pOpenGLComposite->InitDeckLink())
+			if (pOpenGLComposite->InitializeVideoIO())
 			{
 				wglMakeCurrent( NULL, NULL );
 				if (pOpenGLComposite->Start())
@@ -423,11 +423,11 @@ LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
 					PostMessage(hWnd, kCreateStatusStripMessage, 0, 0);
 					break;						// success
 				}
-				MessageBoxA(NULL, "The OpenGL/DeckLink runtime initialized, but playout failed to start. See the previous DeckLink start message for the failing call.", "Startup failed", MB_OK | MB_ICONERROR);
+				MessageBoxA(NULL, "The OpenGL/video I/O runtime initialized, but playout failed to start. See the previous start message for the failing call.", "Startup failed", MB_OK | MB_ICONERROR);
 			}
 			else
 			{
-				MessageBoxA(NULL, "The OpenGL/DeckLink runtime failed to initialize. See the previous initialization message for the failing call.", "Startup failed", MB_OK | MB_ICONERROR);
+				MessageBoxA(NULL, "The OpenGL/video I/O runtime failed to initialize. See the previous initialization message for the failing call.", "Startup failed", MB_OK | MB_ICONERROR);
 			}
 
 			// Failed to initialize - cleanup
@@ -438,7 +438,7 @@ LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
 			}
 			catch (...)
 			{
-				ShowUnhandledExceptionMessage("Startup failed while creating the OpenGL/DeckLink runtime.");
+				ShowUnhandledExceptionMessage("Startup failed while creating the OpenGL/video I/O runtime.");
 				PostMessage(hWnd, WM_CLOSE, 0, 0);
 				break;
 			}
@@ -474,7 +474,7 @@ LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
 			}
 			catch (...)
 			{
-				ShowUnhandledExceptionMessage("Shutdown failed while tearing down the OpenGL/DeckLink runtime.");
+				ShowUnhandledExceptionMessage("Shutdown failed while tearing down the OpenGL/video I/O runtime.");
 			}
 
 			// Deselect the current rendering context and delete it

apps/LoopThroughWithOpenGLCompositing/gl/OpenGLComposite.cpp

@@ -1,5 +1,3 @@
-#include "DeckLinkDisplayMode.h"
-#include "DeckLinkSession.h"
 #include "OpenGLComposite.h"
 #include "GLExtensions.h"
 #include "GlRenderConstants.h"
@@ -10,6 +8,7 @@
 #include "PngScreenshotWriter.h"
 #include "RuntimeServices.h"
 #include "ShaderBuildQueue.h"
+#include "VideoIOBackendFactory.h"
 
 #include <algorithm>
 #include <chrono>
@@ -23,7 +22,6 @@
 
 OpenGLComposite::OpenGLComposite(HWND hWnd, HDC hDC, HGLRC hRC) :
 	hGLWnd(hWnd), hGLDC(hDC), hGLRC(hRC),
-	mVideoIO(std::make_unique<DeckLinkSession>()),
 	mRenderer(std::make_unique<OpenGLRenderer>()),
 	mUseCommittedLayerStates(false),
 	mScreenshotRequested(false)
@@ -37,7 +35,7 @@ OpenGLComposite::OpenGLComposite(HWND hWnd, HDC hDC, HGLRC hRC) :
 		[this]() { ProcessScreenshotRequest(); },
 		[this]() { paintGL(); });
 	mVideoIOBridge = std::make_unique<OpenGLVideoIOBridge>(
-		*mVideoIO,
+		nullptr,
 		*mRenderer,
 		*mRenderPipeline,
 		*mRuntimeHost,
@@ -56,20 +54,15 @@ OpenGLComposite::~OpenGLComposite()
 		mRuntimeServices->Stop();
 	if (mShaderBuildQueue)
 		mShaderBuildQueue->Stop();
+	if (mVideoIO)
 		mVideoIO->ReleaseResources();
 	mRenderer->DestroyResources();
 
 	DeleteCriticalSection(&pMutex);
 }
 
-bool OpenGLComposite::InitDeckLink()
+bool OpenGLComposite::InitializeVideoIO()
 {
-	return InitVideoIO();
-}
-
-bool OpenGLComposite::InitVideoIO()
-{
-	VideoFormatSelection		videoModes;
 	std::string						initFailureReason;
 
 	if (mRuntimeHost && mRuntimeHost->GetRepoRoot().empty())
@@ -82,31 +75,31 @@ bool OpenGLComposite::InitVideoIO()
 		}
 	}
 
-	if (mRuntimeHost)
+	if (!mRuntimeHost)
 	{
-		if (!ResolveConfiguredVideoFormats(
+		initFailureReason = "Runtime host is not available.";
-			mRuntimeHost->GetInputVideoFormat(),
+		MessageBoxA(NULL, initFailureReason.c_str(), "Video I/O initialization failed", MB_OK | MB_ICONERROR);
-			mRuntimeHost->GetInputFrameRate(),
-			mRuntimeHost->GetOutputVideoFormat(),
-			mRuntimeHost->GetOutputFrameRate(),
-			videoModes,
-			initFailureReason))
-		{
-			MessageBoxA(NULL, initFailureReason.c_str(), "DeckLink mode configuration error", MB_OK);
 		return false;
 	}
-	}
 
-	if (!mVideoIO->DiscoverDevicesAndModes(videoModes, initFailureReason))
+	const VideoIOConfiguration videoIOConfig = mRuntimeHost->GetVideoIOConfiguration();
+	mVideoIO = CreateVideoIODevice(videoIOConfig.backendId, initFailureReason);
+	if (!mVideoIO)
+	{
+		MessageBoxA(NULL, initFailureReason.c_str(), "Video I/O initialization failed", MB_OK | MB_ICONERROR);
+		return false;
+	}
+	mVideoIOBridge->SetVideoIODevice(mVideoIO.get());
+
+	if (!mVideoIO->DiscoverDevicesAndModes(videoIOConfig, initFailureReason))
 	{
 		const char* title = initFailureReason == "Please install the Blackmagic DeckLink drivers to use the features of this application."
-			? "This application requires the DeckLink drivers installed."
+			? "This application requires the selected video I/O drivers installed."
-			: "DeckLink initialization failed";
+			: "Video I/O initialization failed";
 		MessageBoxA(NULL, initFailureReason.c_str(), title, MB_OK | MB_ICONERROR);
 		return false;
 	}
-	const bool outputAlphaRequired = mRuntimeHost && mRuntimeHost->ExternalKeyingEnabled();
+	if (!mVideoIO->SelectPreferredFormats(videoIOConfig, initFailureReason))
-	if (!mVideoIO->SelectPreferredFormats(videoModes, outputAlphaRequired, initFailureReason))
 		goto error;
 
 	if (! CheckOpenGLExtensions())
@@ -121,9 +114,9 @@ bool OpenGLComposite::InitVideoIO()
 		goto error;
 	}
 
-	PublishVideoIOStatus(mVideoIO->OutputModelName().empty()
+	PublishVideoIOStatus(mVideoIO->DeviceName().empty()
-		? "DeckLink output device selected."
+		? "Video I/O output device selected."
-		: ("Selected output device: " + mVideoIO->OutputModelName()));
+		: ("Selected output device: " + mVideoIO->DeviceName()));
 
 	// Resize window to match output video frame, but scale large formats down by half for viewing.
 	if (mVideoIO->OutputFrameWidth() < 1920)
@@ -131,7 +124,7 @@ bool OpenGLComposite::InitVideoIO()
 	else
 		resizeWindow(mVideoIO->OutputFrameWidth() / 2, mVideoIO->OutputFrameHeight() / 2);
 
-	if (!mVideoIO->ConfigureInput([this](const VideoIOFrame& frame) { mVideoIOBridge->VideoFrameArrived(frame); }, videoModes.input, initFailureReason))
+	if (!mVideoIO->ConfigureInput([this](const VideoIOFrame& frame) { mVideoIOBridge->VideoFrameArrived(frame); }, initFailureReason))
 	{
 		goto error;
 	}
@@ -140,7 +133,7 @@ bool OpenGLComposite::InitVideoIO()
 		mRuntimeHost->SetSignalStatus(false, mVideoIO->InputFrameWidth(), mVideoIO->InputFrameHeight(), mVideoIO->InputDisplayModeName());
 	}
 
-	if (!mVideoIO->ConfigureOutput([this](const VideoIOCompletion& completion) { mVideoIOBridge->PlayoutFrameCompleted(completion); }, videoModes.output, mRuntimeHost && mRuntimeHost->ExternalKeyingEnabled(), initFailureReason))
+	if (!mVideoIO->ConfigureOutput([this](const VideoIOCompletion& completion) { mVideoIOBridge->PlayoutFrameCompleted(completion); }, initFailureReason))
 	{
 		goto error;
 	}
@@ -151,13 +144,16 @@ bool OpenGLComposite::InitVideoIO()
 
 error:
 	if (!initFailureReason.empty())
-		MessageBoxA(NULL, initFailureReason.c_str(), "DeckLink initialization failed", MB_OK | MB_ICONERROR);
+		MessageBoxA(NULL, initFailureReason.c_str(), "Video I/O initialization failed", MB_OK | MB_ICONERROR);
 	mVideoIO->ReleaseResources();
 	return false;
 }
 
 void OpenGLComposite::paintGL()
 {
+	if (!mVideoIO)
+		return;
+
 	if (!TryEnterCriticalSection(&pMutex))
 	{
 		ValidateRect(hGLWnd, NULL);
@@ -187,21 +183,13 @@ void OpenGLComposite::resizeWindow(int width, int height)
 
 void OpenGLComposite::PublishVideoIOStatus(const std::string& statusMessage)
 {
-	if (!mRuntimeHost)
+	if (!mRuntimeHost || !mVideoIO)
 		return;
 
 	if (!statusMessage.empty())
 		mVideoIO->SetStatusMessage(statusMessage);
 
-	mRuntimeHost->SetVideoIOStatus(
+	mRuntimeHost->SetVideoIOStatus(mVideoIO->State());
-		"decklink",
-		mVideoIO->OutputModelName(),
-		mVideoIO->SupportsInternalKeying(),
-		mVideoIO->SupportsExternalKeying(),
-		mVideoIO->KeyerInterfaceAvailable(),
-		mRuntimeHost->ExternalKeyingEnabled(),
-		mVideoIO->ExternalKeyingActive(),
-		mVideoIO->StatusMessage());
 }
 
 bool OpenGLComposite::InitOpenGLState()

apps/LoopThroughWithOpenGLCompositing/gl/OpenGLComposite.h

@@ -39,8 +39,7 @@ public:
 	OpenGLComposite(HWND hWnd, HDC hDC, HGLRC hRC);
 	~OpenGLComposite();
 
-	bool InitDeckLink();
+	bool InitializeVideoIO();
-	bool InitVideoIO();
 	bool Start();
 	bool Stop();
 	bool ReloadShader();

apps/LoopThroughWithOpenGLCompositing/gl/pipeline/OpenGLVideoIOBridge.cpp

@@ -7,7 +7,7 @@
 #include <gl/gl.h>
 
 OpenGLVideoIOBridge::OpenGLVideoIOBridge(
-	VideoIODevice& videoIO,
+	VideoIODevice* videoIO,
 	OpenGLRenderer& renderer,
 	OpenGLRenderPipeline& renderPipeline,
 	RuntimeHost& runtimeHost,
@@ -24,6 +24,11 @@ OpenGLVideoIOBridge::OpenGLVideoIOBridge(
 {
 }
 
+void OpenGLVideoIOBridge::SetVideoIODevice(VideoIODevice* videoIO)
+{
+	mVideoIO = videoIO;
+}
+
 void OpenGLVideoIOBridge::RecordFramePacing(VideoIOCompletionResult completionResult)
 {
 	const auto now = std::chrono::steady_clock::now();
@@ -57,7 +62,10 @@ void OpenGLVideoIOBridge::RecordFramePacing(VideoIOCompletionResult completionRe
 
 void OpenGLVideoIOBridge::VideoFrameArrived(const VideoIOFrame& inputFrame)
 {
-	const VideoIOState& state = mVideoIO.State();
+	if (mVideoIO == nullptr)
+		return;
+
+	const VideoIOState& state = mVideoIO->State();
 	mRuntimeHost.TrySetSignalStatus(!inputFrame.hasNoInputSource, state.inputFrameSize.width, state.inputFrameSize.height, state.inputDisplayModeName);
 
 	if (inputFrame.hasNoInputSource || inputFrame.bytes == nullptr)
@@ -91,17 +99,20 @@ void OpenGLVideoIOBridge::VideoFrameArrived(const VideoIOFrame& inputFrame)
 
 void OpenGLVideoIOBridge::PlayoutFrameCompleted(const VideoIOCompletion& completion)
 {
+	if (mVideoIO == nullptr)
+		return;
+
 	RecordFramePacing(completion.result);
 
 	EnterCriticalSection(&mMutex);
 
 	VideoIOOutputFrame outputFrame;
-	if (!mVideoIO.BeginOutputFrame(outputFrame))
+	if (!mVideoIO->BeginOutputFrame(outputFrame))
 	{
 		LeaveCriticalSection(&mMutex);
 		return;
 	}
-	const VideoIOState& state = mVideoIO.State();
+	const VideoIOState& state = mVideoIO->State();
 	RenderPipelineFrameContext frameContext;
 	frameContext.videoState = state;
 	frameContext.completion = completion;
@@ -111,12 +122,12 @@ void OpenGLVideoIOBridge::PlayoutFrameCompleted(const VideoIOCompletion& complet
 
 	mRenderPipeline.RenderFrame(frameContext, outputFrame);
 
-	mVideoIO.EndOutputFrame(outputFrame);
+	mVideoIO->EndOutputFrame(outputFrame);
 
-	mVideoIO.AccountForCompletionResult(completion.result);
+	mVideoIO->AccountForCompletionResult(completion.result);
 
 	// Schedule the next frame for playout
-	mVideoIO.ScheduleOutputFrame(outputFrame);
+	mVideoIO->ScheduleOutputFrame(outputFrame);
 
 	wglMakeCurrent(NULL, NULL);
 

apps/LoopThroughWithOpenGLCompositing/gl/pipeline/OpenGLVideoIOBridge.h

@@ -13,7 +13,7 @@ class OpenGLVideoIOBridge
 {
 public:
 	OpenGLVideoIOBridge(
-		VideoIODevice& videoIO,
+		VideoIODevice* videoIO,
 		OpenGLRenderer& renderer,
 		OpenGLRenderPipeline& renderPipeline,
 		RuntimeHost& runtimeHost,
@@ -21,13 +21,15 @@ public:
 		HDC hdc,
 		HGLRC hglrc);
 
+	void SetVideoIODevice(VideoIODevice* videoIO);
+
 	void VideoFrameArrived(const VideoIOFrame& inputFrame);
 	void PlayoutFrameCompleted(const VideoIOCompletion& completion);
 
 private:
 	void RecordFramePacing(VideoIOCompletionResult completionResult);
 
-	VideoIODevice& mVideoIO;
+	VideoIODevice* mVideoIO;
 	OpenGLRenderer& mRenderer;
 	OpenGLRenderPipeline& mRenderPipeline;
 	RuntimeHost& mRuntimeHost;

apps/LoopThroughWithOpenGLCompositing/runtime/RuntimeHost.cpp

@@ -1228,25 +1228,20 @@ void RuntimeHost::MarkRenderStateDirtyLocked()
 	mRenderStateVersion.fetch_add(1, std::memory_order_relaxed);
 }
 
-void RuntimeHost::SetDeckLinkOutputStatus(const std::string& modelName, bool supportsInternalKeying, bool supportsExternalKeying,
+void RuntimeHost::SetVideoIOStatus(const VideoIOState& state)
-	bool keyerInterfaceAvailable, bool externalKeyingRequested, bool externalKeyingActive, const std::string& statusMessage)
-{
-	SetVideoIOStatus("decklink", modelName, supportsInternalKeying, supportsExternalKeying, keyerInterfaceAvailable,
-		externalKeyingRequested, externalKeyingActive, statusMessage);
-}
-
-void RuntimeHost::SetVideoIOStatus(const std::string& backendName, const std::string& modelName, bool supportsInternalKeying, bool supportsExternalKeying,
-	bool keyerInterfaceAvailable, bool externalKeyingRequested, bool externalKeyingActive, const std::string& statusMessage)
 {
 	std::lock_guard<std::mutex> lock(mMutex);
-	mDeckLinkOutputStatus.backendName = backendName;
+	mVideoIOStatus.backendId = state.backendId;
-	mDeckLinkOutputStatus.modelName = modelName;
+	mVideoIOStatus.deviceName = state.deviceName;
-	mDeckLinkOutputStatus.supportsInternalKeying = supportsInternalKeying;
+	mVideoIOStatus.capabilities = state.capabilities;
-	mDeckLinkOutputStatus.supportsExternalKeying = supportsExternalKeying;
+	mVideoIOStatus.hasInputDevice = state.hasInputDevice;
-	mDeckLinkOutputStatus.keyerInterfaceAvailable = keyerInterfaceAvailable;
+	mVideoIOStatus.hasInputSource = state.hasInputSource;
-	mDeckLinkOutputStatus.externalKeyingRequested = externalKeyingRequested;
+	mVideoIOStatus.inputDisplayModeName = state.inputDisplayModeName;
-	mDeckLinkOutputStatus.externalKeyingActive = externalKeyingActive;
+	mVideoIOStatus.outputDisplayModeName = state.outputDisplayModeName;
-	mDeckLinkOutputStatus.statusMessage = statusMessage;
+	mVideoIOStatus.externalKeyingRequested = state.externalKeyingRequested;
+	mVideoIOStatus.externalKeyingActive = state.externalKeyingActive;
+	mVideoIOStatus.statusMessage = state.statusMessage;
+	mVideoIOStatus.formatStatusMessage = state.formatStatusMessage;
 }
 
 void RuntimeHost::SetPerformanceStats(double frameBudgetMilliseconds, double renderMilliseconds)
@@ -1481,61 +1476,67 @@ bool RuntimeHost::LoadConfig(std::string& error)
 		const double configuredValue = maxTemporalHistoryFramesValue->asNumber(static_cast<double>(mConfig.maxTemporalHistoryFrames));
 		mConfig.maxTemporalHistoryFrames = configuredValue <= 0.0 ? 0u : static_cast<unsigned>(configuredValue);
 	}
+	if (const JsonValue* videoBackendValue = configJson.find("videoBackend"))
+	{
+		VideoIOBackendId backendId = mConfig.videoIO.backendId;
+		if (videoBackendValue->isString() && ParseVideoIOBackendId(videoBackendValue->asString(), backendId))
+			mConfig.videoIO.backendId = backendId;
+	}
 	if (const JsonValue* enableExternalKeyingValue = configJson.find("enableExternalKeying"))
-		mConfig.enableExternalKeying = enableExternalKeyingValue->asBoolean(mConfig.enableExternalKeying);
+		mConfig.videoIO.externalKeyingEnabled = enableExternalKeyingValue->asBoolean(mConfig.videoIO.externalKeyingEnabled);
 	if (const JsonValue* videoFormatValue = configJson.find("videoFormat"))
 	{
 		if (videoFormatValue->isString() && !videoFormatValue->asString().empty())
 		{
-			mConfig.inputVideoFormat = videoFormatValue->asString();
+			mConfig.videoIO.inputMode.videoFormat = videoFormatValue->asString();
-			mConfig.outputVideoFormat = videoFormatValue->asString();
+			mConfig.videoIO.outputMode.videoFormat = videoFormatValue->asString();
 		}
 	}
 	if (const JsonValue* frameRateValue = configJson.find("frameRate"))
 	{
 		if (frameRateValue->isString() && !frameRateValue->asString().empty())
 		{
-			mConfig.inputFrameRate = frameRateValue->asString();
+			mConfig.videoIO.inputMode.frameRate = frameRateValue->asString();
-			mConfig.outputFrameRate = frameRateValue->asString();
+			mConfig.videoIO.outputMode.frameRate = frameRateValue->asString();
 		}
 		else if (frameRateValue->isNumber())
 		{
 			std::ostringstream stream;
 			stream << frameRateValue->asNumber();
-			mConfig.inputFrameRate = stream.str();
+			mConfig.videoIO.inputMode.frameRate = stream.str();
-			mConfig.outputFrameRate = stream.str();
+			mConfig.videoIO.outputMode.frameRate = stream.str();
 		}
 	}
 	if (const JsonValue* inputVideoFormatValue = configJson.find("inputVideoFormat"))
 	{
 		if (inputVideoFormatValue->isString() && !inputVideoFormatValue->asString().empty())
-			mConfig.inputVideoFormat = inputVideoFormatValue->asString();
+			mConfig.videoIO.inputMode.videoFormat = inputVideoFormatValue->asString();
 	}
 	if (const JsonValue* inputFrameRateValue = configJson.find("inputFrameRate"))
 	{
 		if (inputFrameRateValue->isString() && !inputFrameRateValue->asString().empty())
-			mConfig.inputFrameRate = inputFrameRateValue->asString();
+			mConfig.videoIO.inputMode.frameRate = inputFrameRateValue->asString();
 		else if (inputFrameRateValue->isNumber())
 		{
 			std::ostringstream stream;
 			stream << inputFrameRateValue->asNumber();
-			mConfig.inputFrameRate = stream.str();
+			mConfig.videoIO.inputMode.frameRate = stream.str();
 		}
 	}
 	if (const JsonValue* outputVideoFormatValue = configJson.find("outputVideoFormat"))
 	{
 		if (outputVideoFormatValue->isString() && !outputVideoFormatValue->asString().empty())
-			mConfig.outputVideoFormat = outputVideoFormatValue->asString();
+			mConfig.videoIO.outputMode.videoFormat = outputVideoFormatValue->asString();
 	}
 	if (const JsonValue* outputFrameRateValue = configJson.find("outputFrameRate"))
 	{
 		if (outputFrameRateValue->isString() && !outputFrameRateValue->asString().empty())
-			mConfig.outputFrameRate = outputFrameRateValue->asString();
+			mConfig.videoIO.outputMode.frameRate = outputFrameRateValue->asString();
 		else if (outputFrameRateValue->isNumber())
 		{
 			std::ostringstream stream;
 			stream << outputFrameRateValue->asNumber();
-			mConfig.outputFrameRate = stream.str();
+			mConfig.videoIO.outputMode.frameRate = stream.str();
 		}
 	}
 
@@ -1867,11 +1868,12 @@ JsonValue RuntimeHost::BuildStateValue() const
 	app.set("oscPort", JsonValue(static_cast<double>(mConfig.oscPort)));
 	app.set("autoReload", JsonValue(mAutoReloadEnabled));
 	app.set("maxTemporalHistoryFrames", JsonValue(static_cast<double>(mConfig.maxTemporalHistoryFrames)));
-	app.set("enableExternalKeying", JsonValue(mConfig.enableExternalKeying));
+	app.set("videoBackend", JsonValue(VideoIOBackendName(mConfig.videoIO.backendId)));
-	app.set("inputVideoFormat", JsonValue(mConfig.inputVideoFormat));
+	app.set("enableExternalKeying", JsonValue(mConfig.videoIO.externalKeyingEnabled));
-	app.set("inputFrameRate", JsonValue(mConfig.inputFrameRate));
+	app.set("inputVideoFormat", JsonValue(mConfig.videoIO.inputMode.videoFormat));
-	app.set("outputVideoFormat", JsonValue(mConfig.outputVideoFormat));
+	app.set("inputFrameRate", JsonValue(mConfig.videoIO.inputMode.frameRate));
-	app.set("outputFrameRate", JsonValue(mConfig.outputFrameRate));
+	app.set("outputVideoFormat", JsonValue(mConfig.videoIO.outputMode.videoFormat));
+	app.set("outputFrameRate", JsonValue(mConfig.videoIO.outputMode.frameRate));
 	root.set("app", app);
 
 	JsonValue runtime = JsonValue::MakeObject();
@@ -1887,25 +1889,22 @@ JsonValue RuntimeHost::BuildStateValue() const
 	video.set("modeName", JsonValue(mSignalModeName));
 	root.set("video", video);
 
-	JsonValue deckLink = JsonValue::MakeObject();
-	deckLink.set("modelName", JsonValue(mDeckLinkOutputStatus.modelName));
-	deckLink.set("supportsInternalKeying", JsonValue(mDeckLinkOutputStatus.supportsInternalKeying));
-	deckLink.set("supportsExternalKeying", JsonValue(mDeckLinkOutputStatus.supportsExternalKeying));
-	deckLink.set("keyerInterfaceAvailable", JsonValue(mDeckLinkOutputStatus.keyerInterfaceAvailable));
-	deckLink.set("externalKeyingRequested", JsonValue(mDeckLinkOutputStatus.externalKeyingRequested));
-	deckLink.set("externalKeyingActive", JsonValue(mDeckLinkOutputStatus.externalKeyingActive));
-	deckLink.set("statusMessage", JsonValue(mDeckLinkOutputStatus.statusMessage));
-	root.set("decklink", deckLink);
-
 	JsonValue videoIO = JsonValue::MakeObject();
-	videoIO.set("backend", JsonValue(mDeckLinkOutputStatus.backendName));
+	videoIO.set("backend", JsonValue(VideoIOBackendName(mVideoIOStatus.backendId)));
-	videoIO.set("modelName", JsonValue(mDeckLinkOutputStatus.modelName));
+	videoIO.set("deviceName", JsonValue(mVideoIOStatus.deviceName));
-	videoIO.set("supportsInternalKeying", JsonValue(mDeckLinkOutputStatus.supportsInternalKeying));
+	videoIO.set("hasInputDevice", JsonValue(mVideoIOStatus.hasInputDevice));
-	videoIO.set("supportsExternalKeying", JsonValue(mDeckLinkOutputStatus.supportsExternalKeying));
+	videoIO.set("hasInputSource", JsonValue(mVideoIOStatus.hasInputSource));
-	videoIO.set("keyerInterfaceAvailable", JsonValue(mDeckLinkOutputStatus.keyerInterfaceAvailable));
+	videoIO.set("inputModeName", JsonValue(mVideoIOStatus.inputDisplayModeName));
-	videoIO.set("externalKeyingRequested", JsonValue(mDeckLinkOutputStatus.externalKeyingRequested));
+	videoIO.set("outputModeName", JsonValue(mVideoIOStatus.outputDisplayModeName));
-	videoIO.set("externalKeyingActive", JsonValue(mDeckLinkOutputStatus.externalKeyingActive));
+	JsonValue capabilities = JsonValue::MakeObject();
-	videoIO.set("statusMessage", JsonValue(mDeckLinkOutputStatus.statusMessage));
+	capabilities.set("supportsInternalKeying", JsonValue(mVideoIOStatus.capabilities.supportsInternalKeying));
+	capabilities.set("supportsExternalKeying", JsonValue(mVideoIOStatus.capabilities.supportsExternalKeying));
+	capabilities.set("keyerInterfaceAvailable", JsonValue(mVideoIOStatus.capabilities.keyerInterfaceAvailable));
+	videoIO.set("capabilities", capabilities);
+	videoIO.set("externalKeyingRequested", JsonValue(mVideoIOStatus.externalKeyingRequested));
+	videoIO.set("externalKeyingActive", JsonValue(mVideoIOStatus.externalKeyingActive));
+	videoIO.set("statusMessage", JsonValue(mVideoIOStatus.statusMessage));
+	videoIO.set("formatStatusMessage", JsonValue(mVideoIOStatus.formatStatusMessage));
 	root.set("videoIO", videoIO);
 
 	JsonValue performance = JsonValue::MakeObject();

apps/LoopThroughWithOpenGLCompositing/runtime/RuntimeHost.h

@@ -2,6 +2,7 @@
 
 #include "RuntimeJson.h"
 #include "ShaderTypes.h"
+#include "VideoIOTypes.h"
 
 #include <atomic>
 #include <chrono>
@@ -38,10 +39,7 @@ public:
 	void SetCompileStatus(bool succeeded, const std::string& message);
 	void SetSignalStatus(bool hasSignal, unsigned width, unsigned height, const std::string& modeName);
 	bool TrySetSignalStatus(bool hasSignal, unsigned width, unsigned height, const std::string& modeName);
-	void SetDeckLinkOutputStatus(const std::string& modelName, bool supportsInternalKeying, bool supportsExternalKeying,
+	void SetVideoIOStatus(const VideoIOState& state);
-		bool keyerInterfaceAvailable, bool externalKeyingRequested, bool externalKeyingActive, const std::string& statusMessage);
-	void SetVideoIOStatus(const std::string& backendName, const std::string& modelName, bool supportsInternalKeying, bool supportsExternalKeying,
-		bool keyerInterfaceAvailable, bool externalKeyingRequested, bool externalKeyingActive, const std::string& statusMessage);
 	void SetPerformanceStats(double frameBudgetMilliseconds, double renderMilliseconds);
 	bool TrySetPerformanceStats(double frameBudgetMilliseconds, double renderMilliseconds);
 	void SetFramePacingStats(double completionIntervalMilliseconds, double smoothedCompletionIntervalMilliseconds,
@@ -65,11 +63,8 @@ public:
 	unsigned short GetServerPort() const { return mServerPort; }
 	unsigned short GetOscPort() const { return mConfig.oscPort; }
 	unsigned GetMaxTemporalHistoryFrames() const { return mConfig.maxTemporalHistoryFrames; }
-	bool ExternalKeyingEnabled() const { return mConfig.enableExternalKeying; }
+	bool ExternalKeyingEnabled() const { return mConfig.videoIO.externalKeyingEnabled; }
-	const std::string& GetInputVideoFormat() const { return mConfig.inputVideoFormat; }
+	VideoIOConfiguration GetVideoIOConfiguration() const { return mConfig.videoIO; }
-	const std::string& GetInputFrameRate() const { return mConfig.inputFrameRate; }
-	const std::string& GetOutputVideoFormat() const { return mConfig.outputVideoFormat; }
-	const std::string& GetOutputFrameRate() const { return mConfig.outputFrameRate; }
 	void SetServerPort(unsigned short port);
 	bool AutoReloadEnabled() const { return mAutoReloadEnabled; }
 
@@ -81,23 +76,22 @@ private:
 		unsigned short oscPort = 9000;
 		bool autoReload = true;
 		unsigned maxTemporalHistoryFrames = 4;
-		bool enableExternalKeying = false;
+		VideoIOConfiguration videoIO;
-		std::string inputVideoFormat = "1080p";
-		std::string inputFrameRate = "59.94";
-		std::string outputVideoFormat = "1080p";
-		std::string outputFrameRate = "59.94";
 	};
 
-	struct DeckLinkOutputStatus
+	struct VideoIOStatusSnapshot
 	{
-		std::string backendName = "decklink";
+		VideoIOBackendId backendId = VideoIOBackendId::DeckLink;
-		std::string modelName;
+		std::string deviceName;
-		bool supportsInternalKeying = false;
+		VideoIOCapabilities capabilities;
-		bool supportsExternalKeying = false;
+		bool hasInputDevice = false;
-		bool keyerInterfaceAvailable = false;
+		bool hasInputSource = false;
+		std::string inputDisplayModeName = "1080p59.94";
+		std::string outputDisplayModeName = "1080p59.94";
 		bool externalKeyingRequested = false;
 		bool externalKeyingActive = false;
 		std::string statusMessage;
+		std::string formatStatusMessage;
 	};
 
 	struct LayerPersistentState
@@ -176,7 +170,7 @@ private:
 	uint64_t mLateFrameCount;
 	uint64_t mDroppedFrameCount;
 	uint64_t mFlushedFrameCount;
-	DeckLinkOutputStatus mDeckLinkOutputStatus;
+	VideoIOStatusSnapshot mVideoIOStatus;
 	unsigned short mServerPort;
 	bool mAutoReloadEnabled;
 	std::chrono::steady_clock::time_point mStartTime;

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOBackendFactory.cpp

@@ -0,0 +1,16 @@
+#include "VideoIOBackendFactory.h"
+
+#include "DeckLinkSession.h"
+#include "VideoIOTypes.h"
+
+std::unique_ptr<VideoIODevice> CreateVideoIODevice(VideoIOBackendId backendId, std::string& error)
+{
+	switch (backendId)
+	{
+	case VideoIOBackendId::DeckLink:
+		return std::make_unique<DeckLinkSession>();
+	}
+
+	error = "Unsupported video I/O backend.";
+	return nullptr;
+}

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOBackendFactory.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include "VideoIOConfig.h"
+
+#include <memory>
+#include <string>
+
+class VideoIODevice;
+
+std::unique_ptr<VideoIODevice> CreateVideoIODevice(VideoIOBackendId backendId, std::string& error);

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOConfig.cpp

@@ -0,0 +1,35 @@
+#include "VideoIOConfig.h"
+
+#include <algorithm>
+#include <cctype>
+
+namespace
+{
+std::string NormalizeToken(std::string value)
+{
+	std::transform(value.begin(), value.end(), value.begin(),
+		[](unsigned char ch) { return static_cast<char>(std::tolower(ch)); });
+	return value;
+}
+}
+
+const char* VideoIOBackendName(VideoIOBackendId backendId)
+{
+	switch (backendId)
+	{
+	case VideoIOBackendId::DeckLink:
+		return "decklink";
+	}
+	return "unknown";
+}
+
+bool ParseVideoIOBackendId(const std::string& value, VideoIOBackendId& backendId)
+{
+	const std::string normalized = NormalizeToken(value);
+	if (normalized.empty() || normalized == "decklink")
+	{
+		backendId = VideoIOBackendId::DeckLink;
+		return true;
+	}
+	return false;
+}

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOConfig.h

@@ -0,0 +1,44 @@
+#pragma once
+
+#include <string>
+
+enum class VideoIOBackendId
+{
+	DeckLink
+};
+
+const char* VideoIOBackendName(VideoIOBackendId backendId);
+bool ParseVideoIOBackendId(const std::string& value, VideoIOBackendId& backendId);
+
+struct FrameSize
+{
+	unsigned width = 0;
+	unsigned height = 0;
+
+	bool IsEmpty() const { return width == 0 || height == 0; }
+};
+
+inline bool operator==(const FrameSize& left, const FrameSize& right)
+{
+	return left.width == right.width && left.height == right.height;
+}
+
+inline bool operator!=(const FrameSize& left, const FrameSize& right)
+{
+	return !(left == right);
+}
+
+struct VideoIOModeConfiguration
+{
+	std::string videoFormat = "1080p";
+	std::string frameRate = "59.94";
+};
+
+struct VideoIOConfiguration
+{
+	VideoIOBackendId backendId = VideoIOBackendId::DeckLink;
+	VideoIOModeConfiguration inputMode;
+	VideoIOModeConfiguration outputMode;
+	bool externalKeyingEnabled = false;
+	bool preferTenBit = true;
+};

apps/LoopThroughWithOpenGLCompositing/videoio/VideoIOTypes.h

@@ -1,15 +1,17 @@
 #pragma once
 
-#include "DeckLinkDisplayMode.h"
+#include "VideoIOConfig.h"
 #include "VideoIOFormat.h"
 
 #include <cstdint>
 #include <functional>
 #include <string>
 
-enum class VideoIOBackend
+struct VideoIOCapabilities
 {
-	DeckLink
+	bool supportsInternalKeying = false;
+	bool supportsExternalKeying = false;
+	bool keyerInterfaceAvailable = false;
 };
 
 enum class VideoIOCompletionResult
@@ -21,15 +23,9 @@ enum class VideoIOCompletionResult
 	Unknown
 };
 
-struct VideoIOConfig
-{
-	VideoFormatSelection videoModes;
-	bool externalKeyingEnabled = false;
-	bool preferTenBit = true;
-};
-
 struct VideoIOState
 {
+	VideoIOBackendId backendId = VideoIOBackendId::DeckLink;
 	FrameSize inputFrameSize;
 	FrameSize outputFrameSize;
 	VideoIOPixelFormat inputPixelFormat = VideoIOPixelFormat::Uyvy8;
@@ -40,14 +36,13 @@ struct VideoIOState
 	unsigned outputPackTextureWidth = 0;
 	std::string inputDisplayModeName = "1080p59.94";
 	std::string outputDisplayModeName = "1080p59.94";
-	std::string outputModelName;
+	std::string deviceName;
 	std::string statusMessage;
 	std::string formatStatusMessage;
 	bool hasInputDevice = false;
 	bool hasInputSource = false;
-	bool supportsInternalKeying = false;
+	VideoIOCapabilities capabilities;
-	bool supportsExternalKeying = false;
+	bool externalKeyingRequested = false;
-	bool keyerInterfaceAvailable = false;
 	bool externalKeyingActive = false;
 	double frameBudgetMilliseconds = 0.0;
 };
@@ -93,11 +88,12 @@ public:
 	using OutputFrameCallback = std::function<void(const VideoIOCompletion&)>;
 
 	virtual ~VideoIODevice() = default;
+	virtual VideoIOBackendId BackendId() const = 0;
 	virtual void ReleaseResources() = 0;
-	virtual bool DiscoverDevicesAndModes(const VideoFormatSelection& videoModes, std::string& error) = 0;
+	virtual bool DiscoverDevicesAndModes(const VideoIOConfiguration& config, std::string& error) = 0;
-	virtual bool SelectPreferredFormats(const VideoFormatSelection& videoModes, bool outputAlphaRequired, std::string& error) = 0;
+	virtual bool SelectPreferredFormats(const VideoIOConfiguration& config, std::string& error) = 0;
-	virtual bool ConfigureInput(InputFrameCallback callback, const VideoFormat& inputVideoMode, std::string& error) = 0;
+	virtual bool ConfigureInput(InputFrameCallback callback, std::string& error) = 0;
-	virtual bool ConfigureOutput(OutputFrameCallback callback, const VideoFormat& outputVideoMode, bool externalKeyingEnabled, std::string& error) = 0;
+	virtual bool ConfigureOutput(OutputFrameCallback callback, std::string& error) = 0;
 	virtual bool Start() = 0;
 	virtual bool Stop() = 0;
 	virtual const VideoIOState& State() const = 0;
@@ -126,10 +122,11 @@ public:
 	unsigned OutputPackTextureWidth() const { return State().outputPackTextureWidth; }
 	const std::string& FormatStatusMessage() const { return State().formatStatusMessage; }
 	const std::string& InputDisplayModeName() const { return State().inputDisplayModeName; }
-	const std::string& OutputModelName() const { return State().outputModelName; }
+	const std::string& DeviceName() const { return State().deviceName; }
-	bool SupportsInternalKeying() const { return State().supportsInternalKeying; }
+	bool SupportsInternalKeying() const { return State().capabilities.supportsInternalKeying; }
-	bool SupportsExternalKeying() const { return State().supportsExternalKeying; }
+	bool SupportsExternalKeying() const { return State().capabilities.supportsExternalKeying; }
-	bool KeyerInterfaceAvailable() const { return State().keyerInterfaceAvailable; }
+	bool KeyerInterfaceAvailable() const { return State().capabilities.keyerInterfaceAvailable; }
+	bool ExternalKeyingRequested() const { return State().externalKeyingRequested; }
 	bool ExternalKeyingActive() const { return State().externalKeyingActive; }
 	const std::string& StatusMessage() const { return State().statusMessage; }
 	double FrameBudgetMilliseconds() const { return State().frameBudgetMilliseconds; }

apps/LoopThroughWithOpenGLCompositing/videoio/decklink/DeckLinkDisplayMode.cpp

@@ -13,10 +13,10 @@ std::string NormalizeModeToken(const std::string& value)
 	return normalized;
 }
 
-bool ResolveConfiguredDisplayMode(const std::string& videoFormat, const std::string& frameRate, BMDDisplayMode& displayMode, std::string& displayModeName)
+bool ResolveConfiguredDeckLinkDisplayMode(const VideoIOModeConfiguration& mode, BMDDisplayMode& displayMode, std::string& displayModeName)
 {
-	VideoFormat videoMode;
+	DeckLinkVideoMode videoMode;
-	if (!ResolveConfiguredVideoFormat(videoFormat, frameRate, videoMode))
+	if (!ResolveConfiguredDeckLinkVideoMode(mode, videoMode))
 		return false;
 
 	displayMode = videoMode.displayMode;
@@ -24,10 +24,10 @@ bool ResolveConfiguredDisplayMode(const std::string& videoFormat, const std::str
 	return true;
 }
 
-bool ResolveConfiguredVideoFormat(const std::string& videoFormat, const std::string& frameRate, VideoFormat& videoMode)
+bool ResolveConfiguredDeckLinkVideoMode(const VideoIOModeConfiguration& mode, DeckLinkVideoMode& videoMode)
 {
-	const std::string formatToken = NormalizeModeToken(videoFormat);
+	const std::string formatToken = NormalizeModeToken(mode.videoFormat);
-	const std::string frameToken = NormalizeModeToken(frameRate);
+	const std::string frameToken = NormalizeModeToken(mode.frameRate);
 	const std::string combinedToken = formatToken + frameToken;
 
 	struct ModeOption
@@ -98,25 +98,22 @@ bool ResolveConfiguredVideoFormat(const std::string& videoFormat, const std::str
 	return false;
 }
 
-bool ResolveConfiguredVideoFormats(
+bool ResolveConfiguredDeckLinkVideoModes(
-	const std::string& inputVideoFormat,
+	const VideoIOConfiguration& config,
-	const std::string& inputFrameRate,
+	DeckLinkVideoModeSelection& videoModes,
-	const std::string& outputVideoFormat,
-	const std::string& outputFrameRate,
-	VideoFormatSelection& videoModes,
 	std::string& error)
 {
-	if (!ResolveConfiguredVideoFormat(inputVideoFormat, inputFrameRate, videoModes.input))
+	if (!ResolveConfiguredDeckLinkVideoMode(config.inputMode, videoModes.input))
 	{
-		error = "Unsupported DeckLink inputVideoFormat/inputFrameRate in config/runtime-host.json: " +
+		error = "Unsupported DeckLink input mode in config/runtime-host.json: " +
-			inputVideoFormat + " / " + inputFrameRate;
+			config.inputMode.videoFormat + " / " + config.inputMode.frameRate;
 		return false;
 	}
 
-	if (!ResolveConfiguredVideoFormat(outputVideoFormat, outputFrameRate, videoModes.output))
+	if (!ResolveConfiguredDeckLinkVideoMode(config.outputMode, videoModes.output))
 	{
-		error = "Unsupported DeckLink outputVideoFormat/outputFrameRate in config/runtime-host.json: " +
+		error = "Unsupported DeckLink output mode in config/runtime-host.json: " +
-			outputVideoFormat + " / " + outputFrameRate;
+			config.outputMode.videoFormat + " / " + config.outputMode.frameRate;
 		return false;
 	}
 

apps/LoopThroughWithOpenGLCompositing/videoio/decklink/DeckLinkDisplayMode.h

@@ -1,47 +1,27 @@
 #pragma once
 
 #include "DeckLinkAPI_h.h"
+#include "VideoIOConfig.h"
 
 #include <string>
 
-struct FrameSize
+struct DeckLinkVideoMode
-{
-	unsigned width = 0;
-	unsigned height = 0;
-
-	bool IsEmpty() const { return width == 0 || height == 0; }
-};
-
-inline bool operator==(const FrameSize& left, const FrameSize& right)
-{
-	return left.width == right.width && left.height == right.height;
-}
-
-inline bool operator!=(const FrameSize& left, const FrameSize& right)
-{
-	return !(left == right);
-}
-
-struct VideoFormat
 {
 	BMDDisplayMode displayMode = bmdModeHD1080p5994;
 	std::string displayName = "1080p59.94";
 };
 
-struct VideoFormatSelection
+struct DeckLinkVideoModeSelection
 {
-	VideoFormat input;
+	DeckLinkVideoMode input;
-	VideoFormat output;
+	DeckLinkVideoMode output;
 };
 
 std::string NormalizeModeToken(const std::string& value);
-bool ResolveConfiguredDisplayMode(const std::string& videoFormat, const std::string& frameRate, BMDDisplayMode& displayMode, std::string& displayModeName);
+bool ResolveConfiguredDeckLinkDisplayMode(const VideoIOModeConfiguration& mode, BMDDisplayMode& displayMode, std::string& displayModeName);
-bool ResolveConfiguredVideoFormat(const std::string& videoFormat, const std::string& frameRate, VideoFormat& videoMode);
+bool ResolveConfiguredDeckLinkVideoMode(const VideoIOModeConfiguration& mode, DeckLinkVideoMode& videoMode);
-bool ResolveConfiguredVideoFormats(
+bool ResolveConfiguredDeckLinkVideoModes(
-	const std::string& inputVideoFormat,
+	const VideoIOConfiguration& config,
-	const std::string& inputFrameRate,
+	DeckLinkVideoModeSelection& videoModes,
-	const std::string& outputVideoFormat,
-	const std::string& outputFrameRate,
-	VideoFormatSelection& videoModes,
 	std::string& error);
 bool FindDeckLinkDisplayMode(IDeckLinkDisplayModeIterator* iterator, BMDDisplayMode targetMode, IDeckLinkDisplayMode** foundMode);

apps/LoopThroughWithOpenGLCompositing/videoio/decklink/DeckLinkSession.cpp

@@ -92,14 +92,19 @@ void DeckLinkSession::ReleaseResources()
 	output.Release();
 }
 
-bool DeckLinkSession::DiscoverDevicesAndModes(const VideoFormatSelection& videoModes, std::string& error)
+bool DeckLinkSession::DiscoverDevicesAndModes(const VideoIOConfiguration& config, std::string& error)
 {
 	CComPtr<IDeckLinkIterator> deckLinkIterator;
 	CComPtr<IDeckLinkDisplayMode> inputMode;
 	CComPtr<IDeckLinkDisplayMode> outputMode;
 
-	mState.inputDisplayModeName = videoModes.input.displayName;
+	mState.backendId = BackendId();
-	mState.outputDisplayModeName = videoModes.output.displayName;
+	mState.externalKeyingRequested = config.externalKeyingEnabled;
+	if (!ResolveConfiguredDeckLinkVideoModes(config, mConfiguredModes, error))
+		return false;
+
+	mState.inputDisplayModeName = mConfiguredModes.input.displayName;
+	mState.outputDisplayModeName = mConfiguredModes.output.displayName;
 
 	HRESULT result = CoCreateInstance(CLSID_CDeckLinkIterator, nullptr, CLSCTX_ALL, IID_IDeckLinkIterator, reinterpret_cast<void**>(&deckLinkIterator));
 	if (FAILED(result))
@@ -151,9 +156,9 @@ bool DeckLinkSession::DiscoverDevicesAndModes(const VideoFormatSelection& videoM
 				output.Release();
 			else
 			{
-				mState.outputModelName = modelName;
+				mState.deviceName = modelName;
-				mState.supportsInternalKeying = deviceSupportsInternalKeying;
+				mState.capabilities.supportsInternalKeying = deviceSupportsInternalKeying;
-				mState.supportsExternalKeying = deviceSupportsExternalKeying;
+				mState.capabilities.supportsExternalKeying = deviceSupportsExternalKeying;
 			}
 		}
 
@@ -178,9 +183,9 @@ bool DeckLinkSession::DiscoverDevicesAndModes(const VideoFormatSelection& videoM
 		return false;
 	}
 
-	if (input && !FindDeckLinkDisplayMode(inputDisplayModeIterator, videoModes.input.displayMode, &inputMode))
+	if (input && !FindDeckLinkDisplayMode(inputDisplayModeIterator, mConfiguredModes.input.displayMode, &inputMode))
 	{
-		error = "Cannot get specified input BMDDisplayMode for configured mode: " + videoModes.input.displayName;
+		error = "Cannot get specified input BMDDisplayMode for configured mode: " + mConfiguredModes.input.displayName;
 		ReleaseResources();
 		return false;
 	}
@@ -194,9 +199,9 @@ bool DeckLinkSession::DiscoverDevicesAndModes(const VideoFormatSelection& videoM
 		return false;
 	}
 
-	if (!FindDeckLinkDisplayMode(outputDisplayModeIterator, videoModes.output.displayMode, &outputMode))
+	if (!FindDeckLinkDisplayMode(outputDisplayModeIterator, mConfiguredModes.output.displayMode, &outputMode))
 	{
-		error = "Cannot get specified output BMDDisplayMode for configured mode: " + videoModes.output.displayName;
+		error = "Cannot get specified output BMDDisplayMode for configured mode: " + mConfiguredModes.output.displayName;
 		ReleaseResources();
 		return false;
 	}
@@ -223,7 +228,7 @@ bool DeckLinkSession::DiscoverDevicesAndModes(const VideoFormatSelection& videoM
 	return true;
 }
 
-bool DeckLinkSession::SelectPreferredFormats(const VideoFormatSelection& videoModes, bool outputAlphaRequired, std::string& error)
+bool DeckLinkSession::SelectPreferredFormats(const VideoIOConfiguration& config, std::string& error)
 {
 	if (!output)
 	{
@@ -233,19 +238,19 @@ bool DeckLinkSession::SelectPreferredFormats(const VideoFormatSelection& videoMo
 
 	mState.formatStatusMessage.clear();
 
-	const bool inputTenBitSupported = input != nullptr && InputSupportsFormat(input, videoModes.input.displayMode, bmdFormat10BitYUV);
+	const bool inputTenBitSupported = input != nullptr && InputSupportsFormat(input, mConfiguredModes.input.displayMode, bmdFormat10BitYUV);
 	mState.inputPixelFormat = input != nullptr ? ChoosePreferredVideoIOFormat(inputTenBitSupported) : VideoIOPixelFormat::Uyvy8;
 	if (input != nullptr && !inputTenBitSupported)
 		mState.formatStatusMessage += "DeckLink input does not report 10-bit YUV support for the configured mode; using 8-bit capture. ";
 
-	const bool outputTenBitSupported = OutputSupportsFormat(output, videoModes.output.displayMode, bmdFormat10BitYUV);
+	const bool outputTenBitSupported = OutputSupportsFormat(output, mConfiguredModes.output.displayMode, bmdFormat10BitYUV);
-	const bool outputTenBitYuvaSupported = OutputSupportsFormat(output, videoModes.output.displayMode, bmdFormat10BitYUVA);
+	const bool outputTenBitYuvaSupported = OutputSupportsFormat(output, mConfiguredModes.output.displayMode, bmdFormat10BitYUVA);
-	mState.outputPixelFormat = outputAlphaRequired
+	mState.outputPixelFormat = config.externalKeyingEnabled
 		? (outputTenBitYuvaSupported ? VideoIOPixelFormat::Yuva10 : VideoIOPixelFormat::Bgra8)
 		: (outputTenBitSupported ? VideoIOPixelFormat::V210 : VideoIOPixelFormat::Bgra8);
-	if (outputAlphaRequired && outputTenBitYuvaSupported)
+	if (config.externalKeyingEnabled && outputTenBitYuvaSupported)
 		mState.formatStatusMessage += "External keying requires alpha; using 10-bit YUVA output. ";
-	else if (outputAlphaRequired)
+	else if (config.externalKeyingEnabled)
 		mState.formatStatusMessage += "External keying requires alpha, but DeckLink output does not report 10-bit YUVA support for the configured mode; using 8-bit BGRA output. ";
 	else if (!outputTenBitSupported)
 		mState.formatStatusMessage += "DeckLink output does not report 10-bit YUV support for the configured mode; using 8-bit BGRA output. ";
@@ -286,7 +291,7 @@ bool DeckLinkSession::SelectPreferredFormats(const VideoFormatSelection& videoMo
 	return true;
 }
 
-bool DeckLinkSession::ConfigureInput(InputFrameCallback callback, const VideoFormat& inputVideoMode, std::string& error)
+bool DeckLinkSession::ConfigureInput(InputFrameCallback callback, std::string& error)
 {
 	mInputFrameCallback = std::move(callback);
 
@@ -298,7 +303,7 @@ bool DeckLinkSession::ConfigureInput(InputFrameCallback callback, const VideoFor
 	}
 
 	const BMDPixelFormat deckLinkInputPixelFormat = DeckLinkPixelFormatForVideoIO(mState.inputPixelFormat);
-	if (input->EnableVideoInput(inputVideoMode.displayMode, deckLinkInputPixelFormat, bmdVideoInputFlagDefault) != S_OK)
+	if (input->EnableVideoInput(mConfiguredModes.input.displayMode, deckLinkInputPixelFormat, bmdVideoInputFlagDefault) != S_OK)
 	{
 		if (mState.inputPixelFormat == VideoIOPixelFormat::V210)
 		{
@@ -306,7 +311,7 @@ bool DeckLinkSession::ConfigureInput(InputFrameCallback callback, const VideoFor
 			mState.inputPixelFormat = VideoIOPixelFormat::Uyvy8;
 			mState.inputFrameRowBytes = mState.inputFrameSize.width * 2u;
 			mState.captureTextureWidth = mState.inputFrameSize.width / 2u;
-			if (input->EnableVideoInput(inputVideoMode.displayMode, bmdFormat8BitYUV, bmdVideoInputFlagDefault) == S_OK)
+			if (input->EnableVideoInput(mConfiguredModes.input.displayMode, bmdFormat8BitYUV, bmdVideoInputFlagDefault) == S_OK)
 			{
 				std::ostringstream status;
 				status << "DeckLink formats: capture " << VideoIOPixelFormatName(mState.inputPixelFormat)
@@ -341,26 +346,26 @@ input_enabled:
 	return true;
 }
 
-bool DeckLinkSession::ConfigureOutput(OutputFrameCallback callback, const VideoFormat& outputVideoMode, bool externalKeyingEnabled, std::string& error)
+bool DeckLinkSession::ConfigureOutput(OutputFrameCallback callback, std::string& error)
 {
 	mOutputFrameCallback = std::move(callback);
 
-	if (output->EnableVideoOutput(outputVideoMode.displayMode, bmdVideoOutputFlagDefault) != S_OK)
+	if (output->EnableVideoOutput(mConfiguredModes.output.displayMode, bmdVideoOutputFlagDefault) != S_OK)
 	{
 		error = "DeckLink output setup failed while enabling video output.";
 		return false;
 	}
 
 	if (output->QueryInterface(IID_IDeckLinkKeyer, (void**)&keyer) == S_OK && keyer != NULL)
-		mState.keyerInterfaceAvailable = true;
+		mState.capabilities.keyerInterfaceAvailable = true;
 
-	if (externalKeyingEnabled)
+	if (mState.externalKeyingRequested)
 	{
-		if (!mState.supportsExternalKeying)
+		if (!mState.capabilities.supportsExternalKeying)
 		{
 			mState.statusMessage = "External keying was requested, but the selected DeckLink output does not report external keying support.";
 		}
-		else if (!mState.keyerInterfaceAvailable)
+		else if (!mState.capabilities.keyerInterfaceAvailable)
 		{
 			mState.statusMessage = "External keying was requested, but the selected DeckLink output does not expose the IDeckLinkKeyer interface.";
 		}
@@ -374,7 +379,7 @@ bool DeckLinkSession::ConfigureOutput(OutputFrameCallback callback, const VideoF
 			mState.statusMessage = "External keying is active on the selected DeckLink output.";
 		}
 	}
-	else if (mState.supportsExternalKeying)
+	else if (mState.capabilities.supportsExternalKeying)
 	{
 		mState.statusMessage = "Selected DeckLink output supports external keying. Set enableExternalKeying to true in runtime-host.json to request it.";
 	}

apps/LoopThroughWithOpenGLCompositing/videoio/decklink/DeckLinkSession.h

@@ -20,41 +20,14 @@ public:
 	DeckLinkSession() = default;
 	~DeckLinkSession();
 
+	VideoIOBackendId BackendId() const override { return VideoIOBackendId::DeckLink; }
 	void ReleaseResources() override;
-	bool DiscoverDevicesAndModes(const VideoFormatSelection& videoModes, std::string& error) override;
+	bool DiscoverDevicesAndModes(const VideoIOConfiguration& config, std::string& error) override;
-	bool SelectPreferredFormats(const VideoFormatSelection& videoModes, bool outputAlphaRequired, std::string& error) override;
+	bool SelectPreferredFormats(const VideoIOConfiguration& config, std::string& error) override;
-	bool ConfigureInput(InputFrameCallback callback, const VideoFormat& inputVideoMode, std::string& error) override;
+	bool ConfigureInput(InputFrameCallback callback, std::string& error) override;
-	bool ConfigureOutput(OutputFrameCallback callback, const VideoFormat& outputVideoMode, bool externalKeyingEnabled, std::string& error) override;
+	bool ConfigureOutput(OutputFrameCallback callback, std::string& error) override;
 	bool Start() override;
 	bool Stop() override;
-
-	bool HasInputDevice() const { return mState.hasInputDevice; }
-	bool HasInputSource() const { return mState.hasInputSource; }
-	void SetInputSourceMissing(bool missing) { mState.hasInputSource = !missing; }
-	bool InputOutputDimensionsDiffer() const { return mState.inputFrameSize != mState.outputFrameSize; }
-	const FrameSize& InputFrameSize() const { return mState.inputFrameSize; }
-	const FrameSize& OutputFrameSize() const { return mState.outputFrameSize; }
-	unsigned InputFrameWidth() const { return mState.inputFrameSize.width; }
-	unsigned InputFrameHeight() const { return mState.inputFrameSize.height; }
-	unsigned OutputFrameWidth() const { return mState.outputFrameSize.width; }
-	unsigned OutputFrameHeight() const { return mState.outputFrameSize.height; }
-	VideoIOPixelFormat InputPixelFormat() const { return mState.inputPixelFormat; }
-	VideoIOPixelFormat OutputPixelFormat() const { return mState.outputPixelFormat; }
-	bool InputIsTenBit() const { return VideoIOPixelFormatIsTenBit(mState.inputPixelFormat); }
-	bool OutputIsTenBit() const { return VideoIOPixelFormatIsTenBit(mState.outputPixelFormat); }
-	unsigned InputFrameRowBytes() const { return mState.inputFrameRowBytes; }
-	unsigned OutputFrameRowBytes() const { return mState.outputFrameRowBytes; }
-	unsigned CaptureTextureWidth() const { return mState.captureTextureWidth; }
-	unsigned OutputPackTextureWidth() const { return mState.outputPackTextureWidth; }
-	const std::string& FormatStatusMessage() const { return mState.formatStatusMessage; }
-	const std::string& InputDisplayModeName() const { return mState.inputDisplayModeName; }
-	const std::string& OutputModelName() const { return mState.outputModelName; }
-	bool SupportsInternalKeying() const { return mState.supportsInternalKeying; }
-	bool SupportsExternalKeying() const { return mState.supportsExternalKeying; }
-	bool KeyerInterfaceAvailable() const { return mState.keyerInterfaceAvailable; }
-	bool ExternalKeyingActive() const { return mState.externalKeyingActive; }
-	const std::string& StatusMessage() const { return mState.statusMessage; }
-	void SetStatusMessage(const std::string& message) { mState.statusMessage = message; }
 	const VideoIOState& State() const override { return mState; }
 	VideoIOState& MutableState() override { return mState; }
 	double FrameBudgetMilliseconds() const;
@@ -76,4 +49,5 @@ private:
 	VideoPlayoutScheduler					mScheduler;
 	InputFrameCallback						mInputFrameCallback;
 	OutputFrameCallback						mOutputFrameCallback;
+	DeckLinkVideoModeSelection				mConfiguredModes;
 };

config/runtime-host.json

@@ -2,6 +2,7 @@
   "shaderLibrary": "shaders",
   "serverPort": 8080,
   "oscPort": 9000,
+  "videoBackend": "decklink",
   "inputVideoFormat": "1080p",
   "inputFrameRate": "59.94",
   "outputVideoFormat": "1080p",

tests/RuntimeHostVideoIOStateTests.cpp

@@ -0,0 +1,67 @@
+#include "RuntimeHost.h"
+
+#include <iostream>
+
+namespace
+{
+int gFailures = 0;
+
+void Expect(bool condition, const char* message)
+{
+	if (condition)
+		return;
+
+	std::cerr << "FAIL: " << message << "\n";
+	++gFailures;
+}
+}
+
+int main()
+{
+	RuntimeHost runtimeHost;
+	std::string error;
+	Expect(runtimeHost.Initialize(error), "runtime host initializes");
+	Expect(error.empty(), "runtime host initialization does not report an error");
+
+	VideoIOState state;
+	state.backendId = VideoIOBackendId::DeckLink;
+	state.deviceName = "Test Device";
+	state.hasInputDevice = true;
+	state.hasInputSource = true;
+	state.inputDisplayModeName = "fake input";
+	state.outputDisplayModeName = "fake output";
+	state.capabilities.supportsInternalKeying = true;
+	state.capabilities.supportsExternalKeying = true;
+	state.capabilities.keyerInterfaceAvailable = true;
+	state.externalKeyingRequested = true;
+	state.externalKeyingActive = true;
+	state.statusMessage = "ready";
+	state.formatStatusMessage = "using fake formats";
+	runtimeHost.SetVideoIOStatus(state);
+
+	JsonValue root;
+	Expect(ParseJson(runtimeHost.BuildStateJson(), root, error), "runtime state json parses");
+	Expect(root.find("videoIO") != nullptr, "runtime state exposes videoIO");
+	Expect(root.find("decklink") == nullptr, "runtime state no longer exposes a decklink top-level block");
+
+	const JsonValue* app = root.find("app");
+	Expect(app != nullptr, "runtime state exposes app settings");
+	Expect(app != nullptr && app->find("videoBackend") != nullptr, "app settings expose videoBackend");
+	Expect(app != nullptr && app->find("videoBackend")->asString() == "decklink", "videoBackend serializes as decklink");
+
+	const JsonValue* videoIO = root.find("videoIO");
+	Expect(videoIO != nullptr && videoIO->find("backend") != nullptr, "videoIO exposes backend");
+	Expect(videoIO != nullptr && videoIO->find("backend")->asString() == "decklink", "videoIO backend serializes as decklink");
+	Expect(videoIO != nullptr && videoIO->find("deviceName") != nullptr, "videoIO exposes device name");
+	Expect(videoIO != nullptr && videoIO->find("deviceName")->asString() == "Test Device", "videoIO device name matches");
+	Expect(videoIO != nullptr && videoIO->find("capabilities") != nullptr, "videoIO exposes capabilities");
+
+	if (gFailures != 0)
+	{
+		std::cerr << gFailures << " RuntimeHost video I/O state test failure(s).\n";
+		return 1;
+	}
+
+	std::cout << "RuntimeHost video I/O state tests passed.\n";
+	return 0;
+}

tests/VideoIOBackendFactoryTests.cpp

@@ -0,0 +1,41 @@
+#include "VideoIOBackendFactory.h"
+#include "VideoIOTypes.h"
+
+#include <iostream>
+
+namespace
+{
+int gFailures = 0;
+
+void Expect(bool condition, const char* message)
+{
+	if (condition)
+		return;
+
+	std::cerr << "FAIL: " << message << "\n";
+	++gFailures;
+}
+}
+
+int main()
+{
+	std::string error;
+	std::unique_ptr<VideoIODevice> device = CreateVideoIODevice(VideoIOBackendId::DeckLink, error);
+	Expect(device != nullptr, "decklink backend factory returns a device");
+	Expect(!device || device->BackendId() == VideoIOBackendId::DeckLink, "decklink backend reports decklink id");
+	Expect(error.empty(), "supported backend does not produce an error");
+
+	error.clear();
+	device = CreateVideoIODevice(static_cast<VideoIOBackendId>(999), error);
+	Expect(device == nullptr, "unknown backend id is rejected");
+	Expect(!error.empty(), "unknown backend reports an error");
+
+	if (gFailures != 0)
+	{
+		std::cerr << gFailures << " VideoIO backend factory test failure(s).\n";
+		return 1;
+	}
+
+	std::cout << "VideoIO backend factory tests passed.\n";
+	return 0;
+}

tests/VideoIODeviceFakeTests.cpp

@@ -19,20 +19,26 @@ void Expect(bool condition, const char* message)
 class FakeVideoIODevice : public VideoIODevice
 {
 public:
+	VideoIOBackendId BackendId() const override { return VideoIOBackendId::DeckLink; }
 	void ReleaseResources() override {}
 
-	bool DiscoverDevicesAndModes(const VideoFormatSelection&, std::string&) override
+	bool DiscoverDevicesAndModes(const VideoIOConfiguration&, std::string&) override
 	{
+		mState.backendId = BackendId();
 		mState.inputFrameSize = { 1920, 1080 };
 		mState.outputFrameSize = { 1920, 1080 };
 		mState.inputDisplayModeName = "fake 1080p";
-		mState.outputModelName = "Fake Video IO";
+		mState.outputDisplayModeName = "fake 1080p";
+		mState.deviceName = "Fake Video IO";
+		mState.capabilities.supportsInternalKeying = true;
+		mState.capabilities.supportsExternalKeying = true;
 		mState.hasInputDevice = true;
 		return true;
 	}
 
-	bool SelectPreferredFormats(const VideoFormatSelection&, bool, std::string&) override
+	bool SelectPreferredFormats(const VideoIOConfiguration& config, std::string&) override
 	{
+		mState.externalKeyingRequested = config.externalKeyingEnabled;
 		mState.inputPixelFormat = VideoIOPixelFormat::Uyvy8;
 		mState.outputPixelFormat = VideoIOPixelFormat::Bgra8;
 		mState.inputFrameRowBytes = VideoIORowBytes(mState.inputPixelFormat, mState.inputFrameSize.width);
@@ -42,13 +48,13 @@ public:
 		return true;
 	}
 
-	bool ConfigureInput(InputFrameCallback callback, const VideoFormat&, std::string&) override
+	bool ConfigureInput(InputFrameCallback callback, std::string&) override
 	{
 		mInputCallback = callback;
 		return true;
 	}
 
-	bool ConfigureOutput(OutputFrameCallback callback, const VideoFormat&, bool, std::string&) override
+	bool ConfigureOutput(OutputFrameCallback callback, std::string&) override
 	{
 		mOutputCallback = callback;
 		return true;
@@ -114,19 +120,19 @@ private:
 int main()
 {
 	FakeVideoIODevice device;
-	VideoFormatSelection selection;
+	VideoIOConfiguration config;
 	std::string error;
 	bool inputSeen = false;
 	bool outputSeen = false;
 
-	Expect(device.DiscoverDevicesAndModes(selection, error), "fake discovery succeeds");
+	Expect(device.DiscoverDevicesAndModes(config, error), "fake discovery succeeds");
-	Expect(device.SelectPreferredFormats(selection, false, error), "fake format selection succeeds");
+	Expect(device.SelectPreferredFormats(config, error), "fake format selection succeeds");
 	Expect(device.ConfigureInput([&](const VideoIOFrame& frame) {
 		inputSeen = frame.bytes != nullptr && frame.width == 1920 && frame.pixelFormat == VideoIOPixelFormat::Uyvy8;
-	}, selection.input, error), "fake input config succeeds");
+	}, error), "fake input config succeeds");
 	Expect(device.ConfigureOutput([&](const VideoIOCompletion& completion) {
 		outputSeen = completion.result == VideoIOCompletionResult::Completed;
-	}, selection.output, false, error), "fake output config succeeds");
+	}, error), "fake output config succeeds");
 	Expect(device.Start(), "fake device starts");
 
 	VideoIOOutputFrame outputFrame;