From 00f187d94a6bc20bfce0d7e85f3e0d31e6212814 Mon Sep 17 00:00:00 2001
From: Jaap Haitsma <jaap@haitsma.org>
Date: Wed, 16 Jun 2021 22:18:15 -0400
Subject: [PATCH] Remove unused functions

---
 lib/identify.c | 138 ++-----------------------------------------------
 1 file changed, 4 insertions(+), 134 deletions(-)

diff --git a/lib/identify.c b/lib/identify.c
index c8e2ef3..88b7948 100644
--- a/lib/identify.c
+++ b/lib/identify.c
@@ -537,95 +537,12 @@ static void find_leftmost_to_line(void *user_data, int y, int left, int right)
 	}
 }
 
-/* Do a Bresenham scan from one point to another and count the number
- * of black/white transitions.
- */
-static int timing_scan(const struct quirc *q,
-		       const struct quirc_point *p0,
-		       const struct quirc_point *p1)
-{
-	int n = p1->x - p0->x;
-	int d = p1->y - p0->y;
-	int x = p0->x;
-	int y = p0->y;
-	int *dom, *nondom;
-	int dom_step;
-	int nondom_step;
-	int a = 0;
-	int i;
-	int zero_run_length = 0;
-	int non_zero_run_length = 0;
-	int count = 0;
-
-	if (p0->x < 0 || p0->y < 0 || p0->x >= q->w || p0->y >= q->h)
-		return -1;
-	if (p1->x < 0 || p1->y < 0 || p1->x >= q->w || p1->y >= q->h)
-		return -1;
-
-	if (abs(n) > abs(d)) {
-		int swap = n;
-
-		n = d;
-		d = swap;
-
-		dom = &x;
-		nondom = &y;
-	} else {
-		dom = &y;
-		nondom = &x;
-	}
-
-	if (n < 0) {
-		n = -n;
-		nondom_step = -1;
-	} else {
-		nondom_step = 1;
-	}
-
-	if (d < 0) {
-		d = -d;
-		dom_step = -1;
-	} else {
-		dom_step = 1;
-	}
-
-	x = p0->x;
-	y = p0->y;
-	for (i = 0; i <= d; i++) {
-		int pixel;
-
-		if (y < 0 || y >= q->h || x < 0 || x >= q->w)
-			break;
-
-		pixel = q->pixels[y * q->w + x];
-
-		if (pixel) {
-			non_zero_run_length++;
-			if ((zero_run_length >= 2) && (non_zero_run_length >= 2)) {
-				count++;
-				zero_run_length = 0;
-			}
-		} else {
-			zero_run_length++;
-			non_zero_run_length = 0;
-		}
-
-		a += n;
-		*dom += dom_step;
-		if (a >= d) {
-			*nondom += nondom_step;
-			a -= d;
-		}
-	}
-
-	return count;
-}
-
 static double distance(struct quirc_point a, struct quirc_point b)
 {
-	return sqrt((a.x - b.x)*(a.x - b.x) +  (a.y - b.y)*(a.y - b.y));	
+	return sqrt((a.x - b.x)*(a.x - b.x) +  (a.y - b.y)*(a.y - b.y));
 }
-
+/* Estimate grid size by determing distance between capstones
+ */
 static void measure_grid_size(struct quirc *q, int index)
 {
 	struct quirc_grid *qr = &q->grids[index];
@@ -647,50 +564,6 @@ static void measure_grid_size(struct quirc *q, int index)
 	qr->grid_size =  4*((int)(grid_size_estimate - 17.0 + 2.0) / 4) + 17;
 }
 
-/* Try the measure the timing pattern for a given QR code. This does
- * not require the global perspective to have been set up, but it
- * does require that the capstone corners have been set to their
- * canonical rotation.
- *
- * For each capstone, we find a point in the middle of the ring band
- * which is nearest the centre of the code. Using these points, we do
- * a horizontal and a vertical timing scan.
- */
-static int measure_timing_pattern(struct quirc *q, int index)
-{
-	struct quirc_grid *qr = &q->grids[index];
-	int i;
-	int scan;
-	int ver;
-	int size;
-
-	for (i = 0; i < 3; i++) {
-		static const double us[] = {6.5, 6.5, 0.5};
-		static const double vs[] = {0.5, 6.5, 6.5};
-		struct quirc_capstone *cap = &q->capstones[qr->caps[i]];
-
-		perspective_map(cap->c, us[i], vs[i], &qr->tpep[i]);
-	}
-	
-	int hscan = timing_scan(q, &qr->tpep[1], &qr->tpep[2]);
-	int vscan = timing_scan(q, &qr->tpep[1], &qr->tpep[0]);
-
-	scan = hscan;
-	if (vscan > scan)
-		scan = vscan;
-
-	/* If neither scan worked, we can't go any further. */
-	if (scan < 0)
-		return -1;
-
-	/* Choose the nearest allowable grid size */
-	size = scan * 2 + 13;
-	ver = (size - 15) / 4;
-	qr->grid_size = ver * 4 + 17;
-
-	return 0;
-}
-
 /* Read a cell from a grid using the currently set perspective
  * transform. Returns +/- 1 for black/white, 0 for cells which are
  * out of image bounds.
@@ -952,12 +825,9 @@ static void record_qr_grid(struct quirc *q, int a, int b, int c)
 		cap->qr_grid = qr_index;
 	}
 
-	/* Check the timing pattern. This doesn't require a perspective
+	/* Check the timing pattern by measuring grid size. This doesn't require a perspective
 	 * transform.
 	 */
-	//if (measure_timing_pattern(q, qr_index) < 0)
-	//	goto fail;
-	
 	measure_grid_size(q, qr_index);
 	/* Make an estimate based for the alignment pattern based on extending
 	 * lines from capstones A and C.