Fixing a RGB to BGR color issue with the Outline effect, and adding in unit tests for the Outline effect.

src/effects/Outline.cpp

@@ -119,10 +119,10 @@ cv::Mat Outline::QImageToBGRACvMat(std::shared_ptr<QImage>& qimage) {
 }
 
 std::shared_ptr<QImage> Outline::BGRACvMatToQImage(cv::Mat img) {
-	cv::Mat final_img;
-	cv::cvtColor(img, final_img, cv::COLOR_RGBA2BGRA);
-	QImage qimage(final_img.data, final_img.cols, final_img.rows, final_img.step, QImage::Format_ARGB32);
-	std::shared_ptr<QImage> imgIn = std::make_shared<QImage>(qimage.convertToFormat(QImage::Format_RGBA8888_Premultiplied));
+	// Directly wrap the cv::Mat data in a QImage
+	QImage qimage(img.data, img.cols, img.rows, img.step, QImage::Format_ARGB32);
+	std::shared_ptr<QImage> imgIn = std::make_shared<QImage>(
+		qimage.convertToFormat(QImage::Format_RGBA8888_Premultiplied));
 	return imgIn;
 }
 

src/effects/Outline.h

@@ -27,10 +27,10 @@ namespace openshot
 {
 
 	/**
-	 * @brief This class add the outline around image with transparent background and can be animated
+	 * @brief This class add an outline around image with transparent background and can be animated
 	 * with openshot::Keyframe curves over time.
 	 *
-	 * Since outline effect is pretty useful in many cases, this effect is added to libopenshot.
+	 * Outlines can be added around any image or text, and animated over time.
 	 */
 	class Outline : public EffectBase
 	{
@@ -47,9 +47,9 @@ namespace openshot
 
 	public:
 		Keyframe width;	///< Width of the outline
-		Keyframe blue;	///< Blue of the outline
-		Keyframe green;	///< Green of the outline
 		Keyframe red;	///< Red channel of the outline
+		Keyframe green;	///< Green of the outline
+		Keyframe blue;	///< Blue of the outline
 		Keyframe alpha;	///< Alpha of the outline
 
 		/// Blank constructor, useful when using Json to load the effect properties
@@ -58,11 +58,11 @@ namespace openshot
 		/// Default constructor, which require width, red, green, blue, alpha
 		///
 		/// @param width the width of the outline (between 0 and 1000, rounded to int)
-		/// @param blue the blue channel of the outline (between 0 and 255, rounded to int)
-		/// @param green the green channel of the outline (between 0 and 255, rounded to int)
 		/// @param red the red channel of the outline (between 0 and 255, rounded to int)
+		/// @param green the green channel of the outline (between 0 and 255, rounded to int)
+		/// @param blue the blue channel of the outline (between 0 and 255, rounded to int)
 		/// @param alpha the alpha channel of the outline (between 0 and 255, rounded to int)
-		Outline(Keyframe width, Keyframe blue, Keyframe green, Keyframe red, Keyframe alpha);
+		Outline(Keyframe width, Keyframe red, Keyframe green, Keyframe blue, Keyframe alpha);
 
 		/// @brief This method is required for all derived classes of ClipBase, and returns a
 		/// new openshot::Frame object. All Clip keyframes and effects are resolved into

tests/CMakeLists.txt

@@ -58,6 +58,7 @@ if($CACHE{HAVE_OPENCV})
   list(APPEND OPENSHOT_TESTS
     CVTracker
     CVStabilizer
+    CVOutline
     # CVObjectDetection
   )
 endif()

tests/CVOutline.cpp

@@ -0,0 +1,62 @@
+/**
+ * @file
+ * @brief Unit tests for OpenCV Outline effect
+ * @author Jonathan Thomas <jonathan@openshot.org>
+ *
+ * @ref License
+ */
+
+// Copyright (c) 2008-2025 OpenShot Studios, LLC
+//
+// SPDX-License-Identifier: LGPL-3.0-or-later
+
+#include <sstream>
+#include <memory>
+#include <cmath>
+
+#include "openshot_catch.h"
+
+#include "Clip.h"
+#include "effects/Outline.h"
+
+using namespace openshot;
+
+TEST_CASE( "Outline_Tests", "[libopenshot][opencv][outline]" )
+{
+    // Create a video clip
+    std::stringstream path;
+    path << TEST_MEDIA_PATH << "1F0CF.svg";
+
+    // Open clip
+    openshot::Clip c(path.str());
+    c.Open();
+    auto f = c.GetFrame(1);
+
+    // Create effect constructor (default values)
+    openshot::Outline e1{};
+
+    // Get frame from effect
+    auto f1 = e1.GetFrame(f, 1);
+    std::shared_ptr<QImage> i1 = f1->GetImage();
+
+    // Check effect colors
+    QColor pix1 = i1->pixelColor(3, 32);
+    QColor compare1{0, 0, 0, 0};
+    CHECK(pix1 == compare1);
+
+    // Test another effect constructor
+    openshot::Outline e2(Keyframe(3.0), Keyframe(255.0),
+        Keyframe(0.0), Keyframe(0.0), Keyframe(128.0));
+
+    // Get frame from effect
+    auto f2 = e2.GetFrame(f, 1);
+    std::shared_ptr<QImage> i2 = f2->GetImage();
+
+    // Check effect colors
+    QColor pix2 = i2->pixelColor(3, 32);
+    QColor compare2{0, 0, 255, 128};
+    CHECK(pix2 == compare2);
+
+    // Close clip
+    c.Close();
+}