Split macro-condition-video.cpp UI into per-widget files

This makes it easier to conditionally exclude video-edit-object.cpp
from the build when OpenCV >= 5 drops CascadeClassifier support.

plugins/video/cascade-classifier-detector.cpp

@@ -0,0 +1,109 @@
+#include "cascade-classifier-detector.hpp"
+
+#ifdef ADVSS_CASCADE_SUPPORT
+
+#include "opencv-helpers.hpp"
+#include "log-helper.hpp"
+
+#if CV_VERSION_MAJOR < 5
+#include <opencv2/objdetect.hpp>
+#else
+#include <opencv2/xobjdetect.hpp>
+#endif
+
+namespace advss {
+
+struct CascadeClassifierDetector::Impl {
+	cv::CascadeClassifier cascade;
+};
+
+CascadeClassifierDetector::CascadeClassifierDetector()
+	: _impl(std::make_unique<Impl>())
+{
+}
+
+CascadeClassifierDetector::~CascadeClassifierDetector() = default;
+
+bool CascadeClassifierDetector::IsSupported()
+{
+	return true;
+}
+
+bool CascadeClassifierDetector::Load(const std::string &modelPath)
+{
+	try {
+		if (!_impl->cascade.load(modelPath)) {
+			blog(LOG_WARNING, "failed to load cascade model \"%s\"",
+			     modelPath.c_str());
+			return false;
+		}
+	} catch (...) {
+		blog(LOG_WARNING, "failed to load cascade model \"%s\"",
+		     modelPath.c_str());
+		return false;
+	}
+	return !_impl->cascade.empty();
+}
+
+bool CascadeClassifierDetector::IsLoaded() const
+{
+	return !_impl->cascade.empty();
+}
+
+std::vector<cv::Rect> CascadeClassifierDetector::Detect(QImage &img)
+{
+	if (img.isNull() || _impl->cascade.empty()) {
+		return {};
+	}
+
+	auto image = QImageToMat(img);
+	cv::Mat frameGray;
+	cv::cvtColor(image, frameGray, cv::COLOR_RGBA2GRAY);
+	cv::equalizeHist(frameGray, frameGray);
+
+	std::vector<cv::Rect> objects;
+	try {
+		_impl->cascade.detectMultiScale(frameGray, objects, scaleFactor,
+						minNeighbors, 0, minSize,
+						maxSize);
+	} catch (const std::exception &e) {
+		vblog(LOG_INFO, "detectMultiScale failed: %s", e.what());
+	}
+	return objects;
+}
+
+} // namespace advss
+
+#else // ADVSS_CASCADE_SUPPORT
+
+namespace advss {
+
+struct CascadeClassifierDetector::Impl {};
+
+CascadeClassifierDetector::CascadeClassifierDetector()
+	: _impl(std::make_unique<Impl>())
+{
+}
+
+CascadeClassifierDetector::~CascadeClassifierDetector() = default;
+
+bool CascadeClassifierDetector::IsSupported()
+{
+	return false;
+}
+bool CascadeClassifierDetector::Load(const std::string &)
+{
+	return false;
+}
+bool CascadeClassifierDetector::IsLoaded() const
+{
+	return false;
+}
+std::vector<cv::Rect> CascadeClassifierDetector::Detect(QImage &)
+{
+	return {};
+}
+
+} // namespace advss
+
+#endif // ADVSS_CASCADE_SUPPORT