From a9a75f5d39bb6ef183f2cfaa1e9dac7fa360f722 Mon Sep 17 00:00:00 2001
From: Pavel Charvat <pavel.charvat@netcentrum.cz>
Date: Sat, 16 Sep 2006 09:33:02 +0200
Subject: [PATCH] configurable border bonuses for signature computation

---
 cf/images          | 3 +++
 images/config.c    | 4 ++++
 images/sig-init.c  | 6 +++---
 images/signature.h | 2 ++
 4 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/cf/images b/cf/images
index cd7f61ed..e27df704 100644
--- a/cf/images
+++ b/cf/images
@@ -17,6 +17,9 @@ PostQuantMinSteps	2
 PostQuantMaxSteps	10
 PostQuantThreshold	1
 
+BorderSize		0.2
+BorderBonus		50
+
 TexturedThreshold	0.32
 
 CompareMethod		2
diff --git a/images/config.c b/images/config.c
index a992dbb3..3bda5ed6 100644
--- a/images/config.c
+++ b/images/config.c
@@ -19,6 +19,8 @@ uns *image_sig_prequant_thresholds;
 uns image_sig_postquant_min_steps;
 uns image_sig_postquant_max_steps;
 uns image_sig_postquant_threshold;
+double image_sig_border_size;
+int image_sig_border_bonus;
 double image_sig_textured_threshold;
 uns image_sig_compare_method;
 uns image_sig_cmp_features_weights[IMAGE_VEC_F + IMAGE_REG_H];
@@ -31,6 +33,8 @@ static struct cf_section sig_config = {
     CF_UNS("PostQuantMinSteps", &image_sig_postquant_min_steps),
     CF_UNS("PostQuantMaxSteps", &image_sig_postquant_max_steps),
     CF_UNS("PostQuantThreshold", &image_sig_postquant_threshold),
+    CF_DOUBLE("BorderSize", &image_sig_border_size),
+    CF_INT("BorderBonus", &image_sig_border_bonus),
     CF_DOUBLE("TexturedThreshold", &image_sig_textured_threshold),
     CF_UNS("CompareMethod", &image_sig_compare_method),
     CF_UNS_ARY("CompareFeaturesWeights", image_sig_cmp_features_weights, IMAGE_VEC_F + IMAGE_REG_H),
diff --git a/images/sig-init.c b/images/sig-init.c
index d829930e..3422c745 100644
--- a/images/sig-init.c
+++ b/images/sig-init.c
@@ -192,8 +192,8 @@ image_sig_finish(struct image_sig_data *data, struct image_signature *sig)
   
   /* For each region */
   u64 w_total = 0;
-  uns w_border = (MIN(data->cols, data->rows) + 3) / 4;
-  uns w_mul = 127 * 256 / w_border;
+  uns w_border = MIN(data->cols, data->rows) * image_sig_border_size;
+  int w_mul = image_sig_border_bonus * 256 / w_border;
   for (uns i = 0; i < sig->len; i++)
     {
       struct image_sig_region *r = data->regions + i;
@@ -221,7 +221,7 @@ image_sig_finish(struct image_sig_data *data, struct image_signature *sig)
 	  if (d >= w_border)
 	    w_sum += 128;
 	  else
-	    w_sum += 128 + (d - w_border) * w_mul / 256;
+	    w_sum += 128 + (int)(w_border - d) * w_mul / 256;
 	}
       w_total += w_sum;
       r->w_sum = w_sum;
diff --git a/images/signature.h b/images/signature.h
index 2b93e32a..57867848 100644
--- a/images/signature.h
+++ b/images/signature.h
@@ -5,6 +5,8 @@
 extern uns image_sig_min_width, image_sig_min_height;
 extern uns *image_sig_prequant_thresholds;
 extern uns image_sig_postquant_min_steps, image_sig_postquant_max_steps, image_sig_postquant_threshold;
+extern double image_sig_border_size;
+extern int image_sig_border_bonus;
 extern double image_sig_textured_threshold;
 extern uns image_sig_compare_method, image_sig_cmp_features_weights[];
 
-- 
2.39.2