From: ozzloy <ozzloy+github_com@gmail.com>
Date: Mon, 9 Feb 2009 09:09:37 +0000 (-0800)
Subject: making separate IplImage to hold mirrored image.  this avoids flickering
X-Git-Url: http://challenge-bot.com/repos/?p=ozzloy%40gmail.com%2Foble;a=commitdiff_plain;h=0d6b136c9c9782a65099c30269ce583ca70dd360

making separate IplImage to hold mirrored image.  this avoids flickering
---

diff --git a/hello-world.cpp b/hello-world.cpp
index 62f59fa..f72a547 100644
--- a/hello-world.cpp
+++ b/hello-world.cpp
@@ -21,6 +21,9 @@
 #include <highgui.h>
 #include <stdio.h>
 
+// argument for cvFlip(src, dest, FLIP_TYPE)
+#define VERTICAL_FLIP 1
+
 CvHaarClassifierCascade* load_object_detector(const char* cascade_path)
 {
 	return (CvHaarClassifierCascade*)cvLoad(cascade_path);
@@ -80,10 +83,18 @@ int main(int argc, char** argv)
 	// Create a window in which the captured images will be presented
 	cvNamedWindow("mywindow", CV_WINDOW_AUTOSIZE);
 
+	IplImage* frame = cvQueryFrame(capture);
+	if(!frame) {
+		fprintf(stderr, "ERROR: frame is null...\n");
+		getchar();
+		return -1;
+	}
+	IplImage* flipped =
+		cvCreateImage(cvGetSize(frame), frame->depth, frame->nChannels);
 	// Show the image captured from the camera in the window and repeat
 	while(1) {
 		// Get one frame
-		IplImage* frame = cvQueryFrame(capture);
+		frame = cvQueryFrame(capture);
 		if(!frame) {
 			fprintf(stderr, "ERROR: frame is null...\n");
 			getchar();
@@ -91,10 +102,10 @@ int main(int argc, char** argv)
 		}
 
 		//flip the image so displayed right/left corresponds to physical right/left
-		cvFlip(frame, frame, 1);
+		cvFlip(frame, flipped, VERTICAL_FLIP);
 
-		detect_and_draw_objects(frame, cascade, 1);
-		cvShowImage("mywindow", frame);
+		detect_and_draw_objects(flipped, cascade, 1);
+		cvShowImage("mywindow", flipped);
 		// Do not release the frame!
 
 		//If ESC key pressed, Key=0x10001B under OpenCV 0.9.7(linux version),
@@ -105,5 +116,6 @@ int main(int argc, char** argv)
 	// Release the capture device housekeeping
 	cvReleaseCapture(&capture);
 	cvDestroyWindow("mywindow");
+	cvReleaseImage(&flipped);
 	return 0;
 }