capture: Add keybindings to stop/continue capturing

1 files changed, 68 insertions, 50 deletions

diff --git a/capture.c b/capture.c
index 8576e20..49d360b 100644
--- a/capture.c
+++ b/capture.c
@@ -25,8 +25,59 @@ struct ct {
 	struct {
 		double x1, y1, x2, y2;
 	} rubberband;
+
+	int idle_source;
 };
 
+static gboolean
+capture(gpointer userdata)
+{
+	struct ct *ct = userdata;
+	IplImage *image;
+	guchar *row1, *row2, *p1, *p2;
+	int x, y;
+
+	image = cvQueryFrame(ct->capture);
+	if (!image) {
+		fprintf(stderr, "ERROR: frame is null...\n");
+		exit(EXIT_FAILURE);
+	}
+
+	if (!ct->surface ||
+	    cairo_image_surface_get_width(ct->surface)  != image->width ||
+	    cairo_image_surface_get_height(ct->surface) != image->height) {
+		if (ct->surface)
+			cairo_surface_destroy(ct->surface);
+		ct->surface =
+			cairo_image_surface_create(CAIRO_FORMAT_RGB24,
+						   image->width, image->height);
+	}
+
+	row1 = (guchar *) image->imageData;
+	row2 = cairo_image_surface_get_data(ct->surface);
+	for (y = 0; y < image->height; ++y) {
+		p1 = row1;
+		p2 = row2;
+
+		for (x = 0; x < image->width; ++x) {
+			/*
+			p2[0] = p1[0];
+			p2[1] = p1[1];
+			p2[2] = p1[2];
+			p2[3] = 0;
+			*/
+			memcpy(p2, p1, 3);
+
+			p1 += image->nChannels;
+			p2 += 4;
+		}
+		row1 += image->widthStep;
+		row2 += cairo_image_surface_get_stride(ct->surface);
+	}
+	gtk_widget_queue_draw(ct->drawing_area);
+	return TRUE;
+}
+
 static inline void
 calc_rubberband_rect(struct ct *ct,
 		     double *x, double *y,
@@ -87,9 +138,23 @@ button_release_event(GtkWidget *widget, GdkEventButton *event, gpointer userdata
 static gboolean
 key_event(GtkWidget *widget, GdkEventKey *event, gpointer userdata)
 {
+	struct ct *ct = userdata;
+
 	switch (event->type) {
 	case GDK_KEY_PRESS:
 		switch (event->keyval) {
+		case GDK_KEY_s:
+		case GDK_KEY_S:
+			if (ct->idle_source) {
+				g_source_remove(ct->idle_source);
+				ct->idle_source = 0;
+			}
+			break;
+		case GDK_KEY_c:
+		case GDK_KEY_C:
+			if (!ct->idle_source)
+				ct->idle_source = g_idle_add(capture, ct);
+			break;
 		case GDK_KEY_q:
 		case GDK_KEY_Q:
 			gtk_main_quit();
@@ -148,55 +213,6 @@ draw_cb(GtkWidget *widget, cairo_t *cr, gpointer userdata)
 	return FALSE;
 }
 
-static gboolean
-capture(gpointer userdata)
-{
-	struct ct *ct = userdata;
-	IplImage *image;
-	guchar *row1, *row2, *p1, *p2;
-	int x, y;
-
-	image = cvQueryFrame(ct->capture);
-	if (!image) {
-		fprintf(stderr, "ERROR: frame is null...\n");
-		exit(EXIT_FAILURE);
-	}
-
-	if (!ct->surface ||
-	    cairo_image_surface_get_width(ct->surface)  != image->width ||
-	    cairo_image_surface_get_height(ct->surface) != image->height) {
-		if (ct->surface)
-			cairo_surface_destroy(ct->surface);
-		ct->surface =
-			cairo_image_surface_create(CAIRO_FORMAT_RGB24,
-						   image->width, image->height);
-	}
-
-	row1 = (guchar *) image->imageData;
-	row2 = cairo_image_surface_get_data(ct->surface);
-	for (y = 0; y < image->height; ++y) {
-		p1 = row1;
-		p2 = row2;
-
-		for (x = 0; x < image->width; ++x) {
-			/*
-			p2[0] = p1[0];
-			p2[1] = p1[1];
-			p2[2] = p1[2];
-			p2[3] = 0;
-			*/
-			memcpy(p2, p1, 3);
-
-			p1 += image->nChannels;
-			p2 += 4;
-		}
-		row1 += image->widthStep;
-		row2 += cairo_image_surface_get_stride(ct->surface);
-	}
-	gtk_widget_queue_draw(ct->drawing_area);
-	return TRUE;
-}
-
 int
 main(int argc, char *argv[])
 {
@@ -251,10 +267,12 @@ main(int argc, char *argv[])
 	g_signal_connect(ct.drawing_area, "motion-notify-event",
 			 G_CALLBACK(motion_notify_event), &ct); 
 
-	g_idle_add(capture, &ct);
+	ct.idle_source = g_idle_add(capture, &ct);
 	gtk_widget_show_all(ct.window);
 	gtk_main();
 
+	if (ct.idle_source)
+		g_source_remove(ct.idle_source);
 	cvReleaseCapture(&ct.capture);
 
 	return 0;