Checking for minimum tesseract version, rather than an explicit match

src/openalpr/ocr.cpp

@@ -29,15 +29,14 @@ namespace alpr
   OCR::OCR(Config* config)
   : postProcessor(config)
   {
-    const string EXPECTED_TESSERACT_VERSION = "3.03";
+    const string MINIMUM_TESSERACT_VERSION = "3.03";
 
     this->config = config;
     
-
-    if (startsWith(tesseract.Version(), EXPECTED_TESSERACT_VERSION) == false)
+    if (cmpVersion(tesseract.Version(), MINIMUM_TESSERACT_VERSION.c_str()) < 0)
     {
       std::cerr << "Warning: You are running an unsupported version of Tesseract." << endl;
-      std::cerr << "Expecting version " << EXPECTED_TESSERACT_VERSION << ", your version is: " << tesseract.Version() << endl;
+      std::cerr << "Expecting at least " << MINIMUM_TESSERACT_VERSION << ", your version is: " << tesseract.Version() << endl;
     }
 
     // Tesseract requires the prefix directory to be set as an env variable

src/openalpr/ocr.h

@@ -31,6 +31,7 @@
 #include "constants.h"
 #include "opencv2/imgproc/imgproc.hpp"
 #include "support/filesystem.h"
+#include "support/version.h"
 
 #include "tesseract/baseapi.h"
 

src/openalpr/support/CMakeLists.txt

@@ -6,6 +6,7 @@ set(support_source_files
  tinythread.cpp
  platform.cpp
  utf8.cpp
+ version.cpp
 )
 
 set(regex_source_files

src/openalpr/support/version.cpp

@@ -0,0 +1,30 @@
+#include "version.h"
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <iostream>
+int cmpVersion(const char *v1, const char *v2)
+{
+    int i;
+    int oct_v1[4], oct_v2[4];
+    
+    for (int i = 0; i < 4; i++)
+    {
+      oct_v1[i] = 0;
+      oct_v2[i] = 0;
+    }
+    
+    sscanf(v1, "%d.%d.%d.%d", &oct_v1[0], &oct_v1[1], &oct_v1[2], &oct_v1[3]);
+    sscanf(v2, "%d.%d.%d.%d", &oct_v2[0], &oct_v2[1], &oct_v2[2], &oct_v2[3]);
+
+    
+    for (i = 0; i < 4; i++) {
+        if (oct_v1[i] > oct_v2[i])
+            return 1;
+        else if (oct_v1[i] < oct_v2[i])
+            return -1;
+    }
+
+    return 0;
+}

src/openalpr/support/version.h

@@ -0,0 +1,17 @@
+#ifndef OPENALPR_VERSION_H
+#define OPENALPR_VERSION_H
+
+#include <stdio.h>
+#include <string.h>
+
+/*
+ * return 1 if v1 > v2
+ * return 0 if v1 = v2
+ * return -1 if v1 < v2
+ */
+
+int cmpVersion(const char *v1, const char *v2);
+
+
+#endif	/* OPENALPR_VERSION_H */
+