roi: Split do_roi into interval creation and matching

1 files changed, 53 insertions, 43 deletions

diff --git a/roi.c b/roi.c
index 59eb57a..4c07a96 100644
--- a/roi.c
+++ b/roi.c
@@ -20,6 +20,10 @@ struct roi {
 	struct {
 		double x1, y1, x2, y2;
 	} rubberband;
+
+	struct match_interval {
+		gint min, max;
+	} interval[3];
 };
 
 static inline void
@@ -44,45 +48,29 @@ pixbuf_get(GdkPixbuf *pixbuf, guchar **pixels,
 	if (stride) *stride = gdk_pixbuf_get_rowstride(pixbuf);
 }
 
-static gboolean
-do_roi(struct roi *roi)
+static void
+calc_roi_interval(struct roi *roi, GdkPixbuf *match)
 {
-	GdkPixbuf *match;
-	cairo_rectangle_t area;
 	gint i, s, x, y, width, height, nch, stride;
-	guchar *pix, *row;
+	guchar *p, *row;
 	gint middle[3] = { 0, 0, 0 };
 	gint sigma[3] = { 0, 0, 0 };
-	struct match_interval { gint min, max; } interval[3];
-
-	calc_rubberband_rect(roi, &area.x, &area.y, &area.width, &area.height);
-
-	if (area.width < 1 || area.height < 1)
-		return FALSE;
 
-	match = gdk_pixbuf_new_subpixbuf(roi->input, area.x, area.y,
-					 area.width, area.height);
-	s = area.width * area.height;
-
-	pixbuf_get(match, &row, NULL, NULL, &nch, &stride);
-	for (y = 0; y < area.height; ++y, row += stride) {
-		for (x = 0, pix = row; x < area.width; ++x, pix += nch) {
+	pixbuf_get(match, &row, &width, &height, &nch, &stride);
+	for (y = 0; y < height; ++y, row += stride)
+		for (x = 0, p = row; x < width; ++x, p += nch)
 			for (i = 0; i < 3; ++i)
-				middle[i] += pix[i];
-		}
-	}
+				middle[i] += p[i];
+	s = width * height;
 	for (i = 0; i < 3; ++i)
 		middle[i] /= s;
 
-	pixbuf_get(match, &row, NULL, NULL, NULL, NULL);
-	for (y = 0; y < area.height; ++y, row += stride) {
-		for (x = 0, pix = row; x < area.width; ++x, pix += nch) {
+	row = gdk_pixbuf_get_pixels(match);
+	for (y = 0; y < height; ++y, row += stride)
+		for (x = 0, p = row; x < width; ++x, p += nch)
 			for (i = 0; i < 3; ++i)
-				sigma[i] +=
-					(pix[i] - middle[i]) *
-					(pix[i] - middle[i]);
-		}
-	}
+				sigma[i] += ((p[i] - middle[i]) *
+					     (p[i] - middle[i]));
 	for (i = 0; i < 3; ++i)
 		sigma[i] = sqrt(sigma[i] / (s - 1));
 
@@ -90,32 +78,54 @@ do_roi(struct roi *roi)
 	printf("sigma:  %3d, %3d, %3d\n", sigma[0], sigma[1], sigma[2]);
 
 	for (i = 0; i < 3; ++i) {
-		interval[i].min = middle[i] - 3 * sigma[i];
-		interval[i].max = middle[i] + 3 * sigma[i];
+		roi->interval[i].min = middle[i] - 3 * sigma[i];
+		roi->interval[i].max = middle[i] + 3 * sigma[i];
 		printf("interval %d: [%3d - %3d]\n",
-		       i, interval[i].min, interval[i].max);
+		       i, roi->interval[i].min, roi->interval[i].max);
 	}
+}
 
-	if (roi->modified_input)
-		g_object_unref(roi->modified_input);
-	roi->modified_input = gdk_pixbuf_copy(roi->input);
+static void
+mark_matching_pixels(struct roi *roi, GdkPixbuf *image)
+{
+	gint i, x, y, width, height, nch, stride;
+	guchar *p, *row;
 
-	pixbuf_get(roi->modified_input, &row, &width, &height, &nch, &stride);
+	pixbuf_get(image, &row, &width, &height, &nch, &stride);
 	for (y = 0; y < height; ++y, row += stride) {
-		for (x = 0, pix = row; x < width; ++x, pix += nch) {
-			int H = 1;
+		for (x = 0, p = row; x < width; ++x, p += nch) {
+			gboolean H = TRUE;
 			for (i = 0; i < 3; ++i) {
-				if (!(pix[i] >= interval[i].min &&
-				      pix[i] <= interval[i].max))
-					H = 0;
+				if (!(p[i] >= roi->interval[i].min &&
+				      p[i] <= roi->interval[i].max))
+					H = FALSE;
 			}
-			if (H)
-				pix[0] = pix[1] = pix[2] = 0;
+			if (H) p[0] = p[1] = p[2] = 0;
 		}
 	}
+}
 
+static gboolean
+do_roi(struct roi *roi)
+{
+	GdkPixbuf *match;
+	cairo_rectangle_t area;
+
+	calc_rubberband_rect(roi, &area.x, &area.y, &area.width, &area.height);
+	if (area.width < 1 || area.height < 1)
+		return FALSE;
+
+	match = gdk_pixbuf_new_subpixbuf(roi->input, area.x, area.y,
+					 area.width, area.height);
+	calc_roi_interval(roi, match);
 	g_object_unref(match);
 
+	if (roi->modified_input)
+		g_object_unref(roi->modified_input);
+	roi->modified_input = gdk_pixbuf_copy(roi->input);
+
+	mark_matching_pixels(roi, roi->modified_input);
+
 	return TRUE;
 }