Version 12, December 2010

[GpsPrune.git] / tim / prune / jpeg / ExifGateway.java

diff --git a/tim/prune/jpeg/ExifGateway.java b/tim/prune/jpeg/ExifGateway.java
index c60afb299822c623f7a4abe77a78e485e50bdc00..9fefadf33c78003248e12e119481346c667166d6 100644 (file)
--- a/tim/prune/jpeg/ExifGateway.java
+++ b/tim/prune/jpeg/ExifGateway.java
@@ -1,9 +1,7 @@
 package tim.prune.jpeg;
 
 import java.io.File;
-
 import javax.swing.JOptionPane;
-
 import tim.prune.I18nManager;
 
 /**
@@ -12,10 +10,8 @@ import tim.prune.I18nManager;
  * to the external libmetadata-extractor-java library
  * instead of the included modified routines.
  *
- * To use the internal routines, set the USE_INTERNAL_LIBRARY flag to true
- * and include the internal classes in the compiled jar.
- * To use the external library, set the USE_INTERNAL_LIBRARY flag to false
- * and do not export the internal classes.
+ * Switching between internal and external libraries is
+ * handled by the ExifLibrarySwitch
  */
 public abstract class ExifGateway
 {
@@ -71,4 +67,25 @@ public abstract class ExifGateway
                if (_exifLibrary == null || !_exifLibrary.looksOK()) {key = key + ".failed";}
                return key;
        }
+
+
+
+       /**
+        * @param inNumerator numerator from Rational
+        * @param inDenominator denominator from Rational
+        * @return the value of the specified number as a positive <code>double</code>.
+        * Prevents interpretation of 32 bit numbers as negative, and forces a positive answer
+        */
+       public static final double convertToPositiveValue(int inNumerator, int inDenominator)
+       {
+               if (inDenominator == 0) return 0.0;
+               double numeratorDbl = inNumerator;
+               double denomDbl = inDenominator;
+               if (inNumerator >= 0)
+                       return numeratorDbl / denomDbl;
+               final double correction = Math.pow(2.0, 32);
+               numeratorDbl += correction;
+               if (inDenominator < 0) denomDbl += correction;
+               return numeratorDbl / denomDbl;
+       }
 }