From 2b1e13f8f45bc7175c61a07580daa61ff192b3ee Mon Sep 17 00:00:00 2001
From: Gurpinder Singh Sandhu <gpsinghsandhu@yahoo.com>
Date: Thu, 4 Apr 2013 22:52:07 +0530
Subject: [PATCH] changed surfFeaturesFinder::find() to allow CV_8UC1 type
 images

http://code.opencv.org/issues/2926
---
 modules/stitching/src/matchers.cpp | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/modules/stitching/src/matchers.cpp b/modules/stitching/src/matchers.cpp
index 2231d13..d05afff 100644
--- a/modules/stitching/src/matchers.cpp
+++ b/modules/stitching/src/matchers.cpp
@@ -348,7 +348,15 @@ SurfFeaturesFinder::SurfFeaturesFinder(double hess_thresh, int num_octaves, int
 void SurfFeaturesFinder::find(const Mat &image, ImageFeatures &features)
 {
     Mat gray_image;
-    CV_Assert(image.type() == CV_8UC3);
+    CV_Assert((image.type() == CV_8UC3) || (image.type() == CV_8UC1));
+    if(image.type() == CV_8UC3)
+    {
+        cvtColor(image, gray_image, CV_BGR2GRAY);
+    }
+    else
+    {
+        gray_image = image;
+    }
     cvtColor(image, gray_image, CV_BGR2GRAY);
     if (surf == 0)
     {
-- 
2.7.4