Add option to reduce video matching latency

data/locale/en-US.ini

@@ -151,6 +151,8 @@ AdvSceneSwitcher.condition.video.condition.object="contains object"
 AdvSceneSwitcher.condition.video.askFileAction="Do you want to use an existing file or create a screenshot of the currently selected source?"
 AdvSceneSwitcher.condition.video.askFileAction.file="Use existing file"
 AdvSceneSwitcher.condition.video.askFileAction.screenshot="Create screenshot"
+AdvSceneSwitcher.condition.video.reduceLatency="Reduce matching latency"
+AdvSceneSwitcher.condition.video.reduceLatency.tooltip="Enabling will reduce the matching latency, but will slow down the condition checks of all macros overall."
 AdvSceneSwitcher.condition.video.usePatternForChangedCheck="Use pattern matching"
 AdvSceneSwitcher.condition.video.usePatternForChangedCheck.tooltip="This will allow you to control how much the image has to change for the condition to be true."
 AdvSceneSwitcher.condition.video.patternThreshold="Threshold: "

src/macro-core/macro-action-screenshot.cpp

@@ -24,7 +24,7 @@ void MacroActionScreenshot::CustomScreenshot()
 {
 	auto s = obs_weak_source_get_source(_source);
 	_screenshot.~ScreenshotHelper();
-	new (&_screenshot) ScreenshotHelper(s, true, _path);
+	new (&_screenshot) ScreenshotHelper(s, false, 0, true, _path);
 	obs_source_release(s);
 }
 

src/macro-external/opencv/macro-condition-video.cpp

@@ -82,6 +82,10 @@ bool MacroConditionVideo::CheckCondition()
 		return _lastMatchResult;
 	}
 
+	if (_blockUntilScreenshotDone) {
+		GetScreenshot(true);
+	}
+
 	if (_screenshotData.done) {
 		match = Compare();
 		_lastMatchResult = match;
@@ -94,7 +98,7 @@ bool MacroConditionVideo::CheckCondition()
 		match = _lastMatchResult;
 	}
 
-	if (_getNextScreenshot) {
+	if (!_blockUntilScreenshotDone && _getNextScreenshot) {
 		GetScreenshot();
 	}
 	return match;
@@ -106,6 +110,8 @@ bool MacroConditionVideo::Save(obs_data_t *obj)
 	_video.Save(obj);
 	obs_data_set_int(obj, "condition", static_cast<int>(_condition));
 	obs_data_set_string(obj, "filePath", _file.c_str());
+	obs_data_set_bool(obj, "blockUntilScreenshotDone",
+			  _blockUntilScreenshotDone);
 	obs_data_set_bool(obj, "usePatternForChangedCheck",
 			  _usePatternForChangedCheck);
 	obs_data_set_double(obj, "threshold", _patternThreshold);
@@ -143,6 +149,8 @@ bool MacroConditionVideo::Load(obs_data_t *obj)
 	_condition =
 		static_cast<VideoCondition>(obs_data_get_int(obj, "condition"));
 	_file = obs_data_get_string(obj, "filePath");
+	_blockUntilScreenshotDone =
+		obs_data_get_bool(obj, "blockUntilScreenshotDone");
 	_usePatternForChangedCheck =
 		obs_data_get_bool(obj, "usePatternForChangedCheck");
 	_patternThreshold = obs_data_get_double(obj, "threshold");
@@ -186,11 +194,12 @@ std::string MacroConditionVideo::GetShortDesc()
 	return _video.ToString();
 }
 
-void MacroConditionVideo::GetScreenshot()
+void MacroConditionVideo::GetScreenshot(bool blocking)
 {
 	auto source = obs_weak_source_get_source(_video.GetVideo());
 	_screenshotData.~ScreenshotHelper();
-	new (&_screenshotData) ScreenshotHelper(source);
+	new (&_screenshotData)
+		ScreenshotHelper(source, blocking, GetSwitcher()->interval);
 	obs_source_release(source);
 	_getNextScreenshot = false;
 }
@@ -287,6 +296,8 @@ MacroConditionVideoEdit::MacroConditionVideoEdit(
 	: QWidget(parent),
 	  _videoSelection(new VideoSelectionWidget(this)),
 	  _condition(new QComboBox()),
+	  _reduceLatency(new QCheckBox(obs_module_text(
+		  "AdvSceneSwitcher.condition.video.reduceLatency"))),
 	  _usePatternForChangedCheck(new QCheckBox(obs_module_text(
 		  "AdvSceneSwitcher.condition.video.usePatternForChangedCheck"))),
 	  _imagePath(new FileSelection()),
@@ -326,6 +337,8 @@ MacroConditionVideoEdit::MacroConditionVideoEdit(
 		  "AdvSceneSwitcher.condition.video.showMatch"))),
 	  _previewDialog(this, entryData.get(), &GetSwitcher()->m)
 {
+	_reduceLatency->setToolTip(obs_module_text(
+		"AdvSceneSwitcher.condition.video.reduceLatency.tooltip"));
 	_imagePath->Button()->disconnect();
 	_usePatternForChangedCheck->setToolTip(obs_module_text(
 		"AdvSceneSwitcher.condition.video.usePatternForChangedCheck.tooltip"));
@@ -341,6 +354,8 @@ MacroConditionVideoEdit::MacroConditionVideoEdit(
 			 SLOT(VideoSelectionChanged(const VideoSelection &)));
 	QWidget::connect(_condition, SIGNAL(currentIndexChanged(int)), this,
 			 SLOT(ConditionChanged(int)));
+	QWidget::connect(_reduceLatency, SIGNAL(stateChanged(int)), this,
+			 SLOT(ReduceLatencyChanged(int)));
 	QWidget::connect(_imagePath, SIGNAL(PathChanged(const QString &)), this,
 			 SLOT(ImagePathChanged(const QString &)));
 	QWidget::connect(_imagePath->Button(), SIGNAL(clicked()), this,
@@ -383,6 +398,7 @@ MacroConditionVideoEdit::MacroConditionVideoEdit(
 	std::unordered_map<std::string, QWidget *> widgetPlaceholders = {
 		{"{{videoSources}}", _videoSelection},
 		{"{{condition}}", _condition},
+		{"{{reduceLatency}}", _reduceLatency},
 		{"{{imagePath}}", _imagePath},
 		{"{{minNeighbors}}", _minNeighbors},
 		{"{{minSize}}", _minSize},
@@ -442,6 +458,7 @@ MacroConditionVideoEdit::MacroConditionVideoEdit(
 	mainLayout->addLayout(_sizeLayout);
 	mainLayout->addLayout(_throttleControlLayout);
 	mainLayout->addLayout(_checkAreaControlLayout);
+	mainLayout->addWidget(_reduceLatency);
 	mainLayout->addLayout(showMatchLayout);
 	setLayout(mainLayout);
 
@@ -635,6 +652,16 @@ void MacroConditionVideoEdit::PatternThresholdChanged(double value)
 	_entryData->_patternThreshold = value;
 }
 
+void MacroConditionVideoEdit::ReduceLatencyChanged(int value)
+{
+	if (_loading || !_entryData) {
+		return;
+	}
+
+	std::lock_guard<std::mutex> lock(GetSwitcher()->m);
+	_entryData->_blockUntilScreenshotDone = value;
+}
+
 void MacroConditionVideoEdit::UseAlphaAsMaskChanged(int value)
 {
 	if (_loading || !_entryData) {
@@ -851,6 +878,7 @@ void MacroConditionVideoEdit::UpdateEntryData()
 
 	_videoSelection->SetVideoSelection(_entryData->_video);
 	_condition->setCurrentIndex(static_cast<int>(_entryData->_condition));
+	_reduceLatency->setChecked(_entryData->_blockUntilScreenshotDone);
 	_imagePath->SetPath(QString::fromStdString(_entryData->_file));
 	_usePatternForChangedCheck->setChecked(
 		_entryData->_usePatternForChangedCheck);

src/macro-external/opencv/macro-condition-video.hpp

@@ -40,7 +40,7 @@ public:
 	{
 		return std::make_shared<MacroConditionVideo>(m);
 	}
-	void GetScreenshot();
+	void GetScreenshot(bool blocking = false);
 	bool LoadImageFromFile();
 	bool LoadModelData(std::string &path);
 	std::string GetModelDataPath() { return _modelDataPath; }
@@ -49,6 +49,13 @@ public:
 	VideoSelection _video;
 	VideoCondition _condition = VideoCondition::MATCH;
 	std::string _file = obs_module_text("AdvSceneSwitcher.enterPath");
+	// Enabling this will reduce matching latency, but slow down the
+	// the condition checks of all macros overall.
+	//
+	// If not set the screenshot will be gathered in one interval and
+	// checked in the next one.
+	// If set both operations will happen in the same interval.
+	bool _blockUntilScreenshotDone = false;
 	bool _useAlphaAsMask = false;
 	bool _usePatternForChangedCheck = false;
 	PatternMatchData _patternData;
@@ -107,8 +114,11 @@ public:
 private slots:
 	void VideoSelectionChanged(const VideoSelection &);
 	void ConditionChanged(int cond);
+	void ReduceLatencyChanged(int value);
+
 	void ImagePathChanged(const QString &text);
 	void ImageBrowseButtonClicked();
+
 	void UsePatternForChangedCheckChanged(int value);
 	void PatternThresholdChanged(double);
 	void UseAlphaAsMaskChanged(int value);
@@ -134,8 +144,11 @@ protected:
 	VideoSelectionWidget *_videoSelection;
 	QComboBox *_condition;
 
+	QCheckBox *_reduceLatency;
+
 	QCheckBox *_usePatternForChangedCheck;
 	FileSelection *_imagePath;
+
 	ThresholdSlider *_patternThreshold;
 	QCheckBox *_useAlphaAsMask;
 

src/utils/screenshot-helper.cpp

@@ -1,16 +1,35 @@
 #include "screenshot-helper.hpp"
 #include "advanced-scene-switcher.hpp"
 
+#include <chrono>
+
 static void ScreenshotTick(void *param, float);
 
-ScreenshotHelper::ScreenshotHelper(obs_source_t *source, bool saveToFile,
+ScreenshotHelper::ScreenshotHelper(obs_source_t *source, bool blocking,
+				   int timeout, bool saveToFile,
 				   std::string path)
 	: weakSource(OBSGetWeakRef(source)),
+	  _blocking(blocking),
 	  _saveToFile(saveToFile),
 	  _path(path)
 {
+	std::unique_lock<std::mutex> lock(_mutex);
 	_initDone = true;
 	obs_add_tick_callback(ScreenshotTick, this);
+	if (_blocking) {
+		auto res =
+			_cv.wait_for(lock, std::chrono::milliseconds(timeout));
+		if (res == std::cv_status::timeout) {
+			if (source) {
+				blog(LOG_WARNING,
+				     "Failed to get screenshot in time for source %s",
+				     obs_source_get_name(source));
+			} else {
+				blog(LOG_WARNING,
+				     "Failed to get screenshot in time");
+			}
+		}
+	}
 }
 
 ScreenshotHelper::~ScreenshotHelper()
@@ -104,6 +123,8 @@ void ScreenshotHelper::MarkDone()
 {
 	time = std::chrono::high_resolution_clock::now();
 	done = true;
+	std::unique_lock<std::mutex> lock(_mutex);
+	_cv.notify_all();
 }
 
 void ScreenshotHelper::WriteToFile()
@@ -148,8 +169,8 @@ static void ScreenshotTick(void *param, float)
 		break;
 	case STAGE_COPY_AND_SAVE:
 		data->Copy();
-		data->MarkDone();
 		data->WriteToFile();
+		data->MarkDone();
 
 		obs_remove_tick_callback(ScreenshotTick, data);
 		break;

src/utils/screenshot-helper.hpp

@@ -4,11 +4,14 @@
 #include <QImage>
 #include <chrono>
 #include <thread>
+#include <mutex>
+#include <condition_variable>
 
 class ScreenshotHelper {
 public:
 	ScreenshotHelper() = default;
-	ScreenshotHelper(obs_source_t *source, bool saveToFile = false,
+	ScreenshotHelper(obs_source_t *source, bool blocking = false,
+			 int timeout = 1000, bool saveToFile = false,
 			 std::string path = "");
 	ScreenshotHelper &operator=(const ScreenshotHelper &) = delete;
 	ScreenshotHelper(const ScreenshotHelper &) = delete;
@@ -34,7 +37,10 @@ public:
 
 private:
 	bool _initDone = false;
+	bool _blocking = false;
 	std::thread _saveThread;
 	bool _saveToFile = false;
 	std::string _path = "";
+	std::mutex _mutex;
+	std::condition_variable _cv;
 };