Add a very short conceptiual description of the recognition algorithm

5c85b2ea0cce15af73b74acd67129456037d5d97 · Thomas Jaeger · Jan 2, 2010 13:58

+4 · 1 file changed

stroke.c +4 −0

diff --git a/stroke.c b/stroke.c
index a62b3bc..98683a6 100644
--- a/stroke.c
+++ b/stroke.c
@@ -133,6 +133,10 @@ double stroke_angle_difference(const stroke_t *a, const stroke_t *b, int i, int
 	return fabs(angle_difference(stroke_get_angle(a, i), stroke_get_angle(b, j)));
 }
 
+/* To compare two gestures, we use dynamic programming to minimize (an
+ * approximation) of the integral over the absolute value of the angle
+ * difference among (roughly) all reparametrizations whose slope is always
+ * between 1/2 and 2. */
 double stroke_compare(const stroke_t *a, const stroke_t *b, int *path_x, int *path_y) {
 	int m = a->n - 1;
 	int n = b->n - 1;