From 51965c99362ea1d37fddc513dba6345fb1b8ea94 Mon Sep 17 00:00:00 2001
From: Benjamin Franzke <benjaminfranzke@googlemail.com>
Date: Fri, 25 May 2012 09:24:31 +0200
Subject: cvg: Add GoodFeaturesToTrack filter

---
 cvg.c  | 35 +++++++++++++++++++++++++++++++++++
 cvg.ui |  1 +
 2 files changed, 36 insertions(+)

diff --git a/cvg.c b/cvg.c
index b6fc76e..f327ea6 100644
--- a/cvg.c
+++ b/cvg.c
@@ -259,6 +259,39 @@ gauss_filter(struct cvg *cvg, IplImage *image)
 	return output;
 }
 
+static IplImage *
+good_features_to_track(struct cvg *cvg, IplImage *image)
+{
+	IplImage *output, *gray_frame, *eig_image, *temp_image;
+	CvPoint2D32f corners[100];
+	int corner_count = sizeof(corners)/sizeof(corners[0]);
+	double quality_level = 0.1, min_distance = 5;
+	int i, eig_block_size = 3, use_harris = 0;
+
+	output = cvCreateImage(cvGetSize(image), IPL_DEPTH_8U, 3);
+	cvCopy(image, output, NULL);
+
+	gray_frame = cvCreateImage(cvGetSize(image), IPL_DEPTH_8U, 1);
+	eig_image = cvCreateImage(cvGetSize(image), IPL_DEPTH_32F, 1);
+	temp_image = cvCreateImage(cvGetSize(image), IPL_DEPTH_32F, 1);
+	cvCvtColor(image, gray_frame, CV_BGR2GRAY);
+
+	memset(corners, 0, sizeof corners);
+	cvGoodFeaturesToTrack(gray_frame, eig_image, temp_image,
+			      corners, &corner_count,
+			      quality_level, min_distance,  NULL,
+			      eig_block_size, use_harris, 0.04);
+	for (i = 0; i < corner_count; ++i) {
+		CvPoint center = { corners[i].x, corners[i].y };
+		cvCircle(output, center, 5, CV_RGB(255, 0, 0), 3, 8, 0);
+	}
+	cvReleaseImage(&gray_frame);
+	cvReleaseImage(&eig_image);
+	cvReleaseImage(&temp_image);
+
+	return output;
+}
+
 static IplImage *
 hide_filter(struct cvg *cvg, IplImage *image)
 {
@@ -291,6 +324,8 @@ method_set(GtkComboBox *widget, gpointer userdata)
 		return;
 	if (strcmp(text, "Gauss") == 0)
 		cvg->filter = gauss_filter;
+	else if (strcmp(text, "GoodFeaturesToTrack") == 0)
+		cvg->filter = good_features_to_track;
 	else if (strcmp(text, "Pass-Through") == 0)
 		cvg->filter = pass_through_filter;
 	else if (strcmp(text, "Hide") == 0)
diff --git a/cvg.ui b/cvg.ui
index 4504994..0a821cd 100644
--- a/cvg.ui
+++ b/cvg.ui
@@ -83,6 +83,7 @@
             <items>
               <item>Hide</item>
               <item>Gauss</item>
+              <item>GoodFeaturesToTrack</item>
               <item>Pass-Through</item>
             </items>
             <signal name="changed" handler="method_set" swapped="no"/>
-- 
cgit