histogram

histogram.cc

@@ -12,88 +12,65 @@
 
 
 GtkWidget *histogram_da = NULL;
-GdkPixbuf *histogram_pixbuf = NULL;
+int histogram[3][256];    		// 6* hist_width min, max, min , max.....
-int *hist_minmax = NULL;    // 2* hist_width min, max, min , max.....
+int histogram_max;				// max vlaue
-int hist_width = 0;
 
 extern GtkBuilder *_builder_;			// work around for threads
 
-
-#define S_X(_x_) (((_x_) * clientw / pixbufw))
-#define S_Y(_y_) (((_y_) * clienth / pixbufh))
 void cb_histogramda_draw(GtkWidget *area, cairo_t *cr, int w, int h, gpointer data) {
-	int clientw, clienth, pixbufw, pixbufh;
+	int clientw, clienth, px, py2;
 	GdkRGBA color;
+	char txt[255];
 
 	if (histogram_da == NULL) // should only be called once
 		histogram_da = GTK_WIDGET(gtk_builder_get_object (GTK_BUILDER(_builder_), "histogram-da"));
-
-	//
-	// create or resize pixbuf if needed
 	clienth = gtk_widget_get_allocated_height(histogram_da);
 	clientw = gtk_widget_get_allocated_width(histogram_da);
-	if (histogram_pixbuf == NULL) {
-		histogram_pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, false, 8, clientw, clienth);
-		memset (gdk_pixbuf_get_pixels(histogram_pixbuf), 0, 3 * gdk_pixbuf_get_height(histogram_pixbuf) * gdk_pixbuf_get_width(histogram_pixbuf));
-	}
-
-	pixbufh = gdk_pixbuf_get_height(histogram_pixbuf);
-	pixbufw = gdk_pixbuf_get_width(histogram_pixbuf);
-	if (pixbufw != clientw || pixbufh != clienth) {
-		g_object_unref(histogram_pixbuf);
-		histogram_pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, false, 8, clientw, clienth);
-		memset (gdk_pixbuf_get_pixels(histogram_pixbuf), 0, 3 * gdk_pixbuf_get_height(histogram_pixbuf) * gdk_pixbuf_get_width(histogram_pixbuf));
-	}
 
 	//
 	// put the drawing area on the screen
-    gdk_cairo_set_source_pixbuf(cr, histogram_pixbuf, 0, 0);
     cairo_paint(cr);
     cairo_fill (cr);
 
-	//
+    if (histogram_max == 0) return;
-	// draw cross
+
-	color.blue = 1.0;
+    for (int chan = 0; chan < 3; chan++) {
+		switch (chan) {
+		case 0:
+			color.blue = 0.0;
+			color.red = 1.0;
+			color.green = 0.0;
+			color.alpha = 0.5;
+			break;
+		case 1:
+			color.blue = 0.0;
 			color.red = 0.0;
 			color.green = 1.0;
-	color.alpha = 1.0;
+			color.alpha = 0.5;
-	gdk_cairo_set_source_rgba(cr, &color);
+			break;
-
+		case 2:
-	cairo_move_to(cr, 0, 0);
+			color.blue = 1.0;
-	cairo_line_to(cr, pixbufw, pixbufh);
+			color.red = 0.0;
-	cairo_move_to(cr, pixbufw, 0);
+			color.green = 0.0;
-	cairo_line_to(cr, 0, pixbufh);
+			color.alpha = 0.5;
-
+			break;
-	cairo_stroke(cr);
+		}
-
-	//
-	// draw basic histogram
-	if (hist_minmax != NULL) {
-		//
-		// draw cross
-		color.blue = 0.75;
-		color.red = 0.75;
-		color.green = 0.75;
-		color.alpha = 0.8;
 		gdk_cairo_set_source_rgba(cr, &color);
 
-		int x, i;			// position in histogram
+    	for (int i = 0; i < 256; i++) {
-		int px, py1, py2;	// screen pos x and line from to
+			px = 16 + ((clientw-32) * i) / 256;
-
+			py2 = (clienth-16) - ((clienth-32) * histogram[chan][i]) / histogram_max;
-		for (i = 0, x = 0; x < hist_width; x++) {
 
-			px = (pixbufw * x) / hist_width;
+    		if (i == 0) cairo_move_to(cr, px, py2);
-			py1 = (pixbufh * hist_minmax[i++]) / 255;
+    		else 		cairo_line_to(cr, px, py2);
-			py2 = (pixbufh * hist_minmax[i++]) / 255;
 
-			cairo_move_to(cr, px, py1);
-			cairo_line_to(cr, px, py2);
-
-			cairo_stroke(cr);
     	}
+		cairo_stroke(cr);
     }
 
 	// draw some text
+    snprintf (txt, 255, "%d", histogram_max);
+
 	for (int i = 0; i < 5; i++) {
 		int dx, dy;
 
@@ -125,7 +102,7 @@ void cb_histogramda_draw(GtkWidget *area, cairo_t *cr, int w, int h, gpointer da
 		cairo_select_font_face (cr, "sans-serif", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD);
 		cairo_set_font_size (cr, 12);
 		cairo_move_to (cr, 10+dx, 15+dy);
-    	cairo_show_text(cr, "Test");
+		cairo_show_text(cr, txt);
 		cairo_stroke(cr);
 	}
 };
@@ -135,39 +112,26 @@ void cb_histogramda_draw(GtkWidget *area, cairo_t *cr, int w, int h, gpointer da
  * test function
  */
 void histogram_update(VideoFrame *vf) {
-	int i, x, y, min, max, v;
+	int chan, i, x, y;
 
 	if (vf == NULL) return;
 	if (vf->w <= 0 ) return;
 
-	if (hist_minmax == NULL ) {
+	for (chan = 0; chan < 3; chan++) for (i = 0; i < 256; i++)
-		hist_minmax = (int*) malloc (2 * sizeof(int) * vf->w);
+		histogram[chan][i] = 0;
-		hist_width = vf->w;
-	}
-	if (hist_width != vf->w) {
-		free (hist_minmax);
-		hist_minmax = (int*) malloc (2 * sizeof(int) * vf->w);
-		hist_width = vf->w;
-	}
 
 	for (i = 0, x = 0; x < vf->w; x++) {
 		for (y = 0; y < vf->h; y++) {
-			v = (vf->data[3*y*vf->w+x + 0] +
+			for (chan = 0; chan < 3; chan++) {
-				 vf->data[3*y*vf->w+x + 1] +
+				histogram[chan][vf->data[3*(y*vf->w+x) + chan]]++;
-				 vf->data[3*y*vf->w+x + 2]) / 3;
-			if (y == 0) {
-				min = v;
-				max = v;
 			}
-
-			if (v < min) min = v;
-			if (v > max) max = v;
 		}
-		hist_minmax[i++] = min;
-		hist_minmax[i++] = max;
 	}
 
 	if (histogram_da)
 		gdk_window_invalidate_rect(gtk_widget_get_window(histogram_da), NULL, true);
+
+	for (histogram_max = 0, chan = 0; chan < 3; chan++) for (i = 0; i < 256; i++)
+		if (histogram_max < histogram[chan][i]) histogram_max = histogram[chan][i];
 };