diff --git a/extconf.rb b/extconf.rb
index 6684fb5..834fd88 100755
--- a/extconf.rb
+++ b/extconf.rb
@@ -1,6 +1,18 @@
 #!/usr/bin/env ruby
 require "mkmf"
 
+def cv_version_suffix(incdir)
+  major, minor, subminor = nil, nil, nil
+  open("#{incdir}/opencv2/core/version.hpp", 'r') { |f|
+    f.read.lines.each { |line|
+      major = $1.to_s if line =~ /\A#define\s+CV_MAJOR_VERSION\s+(\d+)\s*\Z/
+      minor = $1.to_s if line =~ /\A#define\s+CV_MINOR_VERSION\s+(\d+)\s*\Z/
+      subminor = $1.to_s if line =~ /\A#define\s+CV_SUBMINOR_VERSION\s+(\d+)\s*\Z/
+    }
+  }
+  major + minor + subminor
+end
+
 incdir, libdir = dir_config("opencv", "/usr/local/include", "/usr/local/lib")
 dir_config("libxml2", "/usr/include", "/usr/lib")
 
@@ -17,18 +29,18 @@ opencv_libraries = ["opencv_calib3d", "opencv_contrib", "opencv_core", "opencv_f
 
 
 puts ">> Check the required libraries..."
-
-OPENCV_VERSION_SUFFIX = '242'
 case CONFIG["arch"]
 when /mswin32/
-  opencv_libraries.map! {|lib| lib + OPENCV_VERSION_SUFFIX }
+  suffix = cv_version_suffix(incdir)
+  opencv_libraries.map! {|lib| lib + suffix }
   have_library("msvcrt")
   opencv_libraries.each {|lib|
     raise "#{lib}.lib not found." unless have_library(lib)
   }
   $CFLAGS << ' /EHsc'
 when /mingw32/
-  opencv_libraries.map! {|lib| lib + OPENCV_VERSION_SUFFIX }
+  suffix = cv_version_suffix(incdir)
+  opencv_libraries.map! {|lib| lib + suffix }
   have_library("msvcrt")
   opencv_libraries.each {|lib|
     raise "lib#{lib} not found." unless have_library(lib)