Flujo óptico método de Farneback

Calcular fluo óptico usando la función calcOpticalFlowFarneback.

Author: devcarmelo

opencv-opticalflow-fb/CMakeLists.txt

@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.4)
+
+project( OpticalFlow_Farneback )
+
+find_package( OpenCV 3.0.0 REQUIRED )
+
+add_executable( ${PROJECT_NAME} optical_flow_farneback.cpp )
+target_link_libraries( ${PROJECT_NAME} ${OpenCV_LIBS} )

opencv-opticalflow-fb/optical_flow_farneback.cpp

@@ -0,0 +1,69 @@
+#include <iostream>
+#include <opencv2\opencv.hpp>
+
+using namespace cv;
+using namespace std;
+
+// Function to compute the optical flow map
+void drawOpticalFlow(const Mat& flowImage, const Mat& flowImageGray)
+{
+    int stepSize = 16;
+    Scalar color = Scalar(0, 255, 0);
+
+    // Draw the uniform grid of points on the input image along with the motion vectors
+    for (int y = 0; y < flowImageGray.rows; y += stepSize)
+    {
+        for (int x = 0; x < flowImageGray.cols; x += stepSize)
+        {
+            // Circles to indicate the uniform grid of points
+            circle(flowImageGray, Point(x, y), 1, color, FILLED);
+
+            // Lines to indicate the motion vectors
+            const Point2f& pt = flowImage.at<Point2f>(y, x);
+            line(flowImageGray, Point(x, y), Point(cvRound(x + pt.x), cvRound(y + pt.y)), color);
+        }
+    }
+}
+
+void main()
+{
+    String window = "OpticalFlow :: Farneback";
+    VideoCapture capture(0);
+    Mat prev_gray;
+
+    // crear la ventana
+    namedWindow(window);
+
+    // bucle de captura de video
+    while (true) {
+
+        Mat frame, gray, flow;
+
+        // capturar el cuadro actual
+        capture >> frame;
+
+        // si no hay datos continuar
+        if (frame.empty()) continue;
+
+        // escalar a la mitad, para mejorar rendimiento
+        resize(frame, frame, Size(), 0.6, 0.6, INTER_LINEAR);
+
+        // convertir a escala de grises
+        cvtColor(frame, gray, COLOR_BGR2GRAY);
+
+        if (!prev_gray.empty())
+        {
+            calcOpticalFlowFarneback(prev_gray, gray, flow, 0.5, 3, 15, 3, 5, 1.1, 0);
+            drawOpticalFlow(flow, frame);
+        }
+
+        // esperar por 30 ms ha que se presione una tecla
+        if(waitKey(30) == 27) break;
+
+        // mostrar la imagen
+        imshow(window, frame);
+
+        // intercambiar las imagenes, la actual es ahora la anterior.
+        cv::swap(prev_gray, gray);
+    }
+}