Incorrect output when date isn't set on camera

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I am using version 2.6.4 of the metadata-extractor library. The following test 
case when run with the attached file as an argument demonstrates a problem with 
reporting the creation date. On the particular camera I used for the image (a 
Nikon E5700v1.0), if the date has not been set, the metadata records the date 
as "0000:00:00 00:00:00" rather than the expected "    :  :     :  :  ". The 
test program therefore prints out:
  Creation date is: Sun Nov 30 00:00:00 MST 2
rather than the expected output of:
  No creation date recorded.

Here is the test program:
import java.text.*;
import java.util.Date;
import java.io.File;
import com.drew.imaging.ImageMetadataReader;
import com.drew.metadata.Metadata;
import com.drew.metadata.exif.ExifSubIFDDirectory;

public class testDate
{
  public static void main(String args[]) throws Exception
  {
    File f = new File(args[0]);
    Metadata metadata = ImageMetadataReader.readMetadata(f);
    // obtain the Exif directory
    ExifSubIFDDirectory directory =
    metadata.getDirectory(ExifSubIFDDirectory.class);
    try
    {
      // query the tag's value
      Date file_date =
          directory.getDate(ExifSubIFDDirectory.TAG_DATETIME_ORIGINAL);
      System.out.println("Creation date is: " + file_date);
    }
    catch (NullPointerException npe)
    {
      System.out.println("No creation date recorded.");
    }
  }
}

I suggest this fix to the library:
diff --git a/Source/com/drew/metadata/Directory.java 
b/Source/com/drew/metadata/Directory.java
index 282bc32..145e930 100644
--- a/Source/com/drew/metadata/Directory.java
+++ b/Source/com/drew/metadata/Directory.java
@@ -743,6 +743,10 @@ public abstract class Directory
             return (java.util.Date)o;

         if (o instanceof String) {
+            String dateString = (String)o;
+            if ("0000:00:00 00:00:00".equals(o))
+                return null;
+              
             // This seems to cover all known Exif date strings
             // Note that "    :  :     :  :  " is a valid date string according to the Exif spec (which means 'unknown date'): http://www.awaresystems.be/imaging/tiff/tifftags/privateifd/exif/datetimeoriginal.html
             String datePatterns[] = {
@@ -752,7 +756,6 @@ public abstract class Directory
                     "yyyy-MM-dd HH:mm",
                     "yyyy.MM.dd HH:mm:ss",
                     "yyyy.MM.dd HH:mm" };
-            String dateString = (String)o;
             for (String datePattern : datePatterns) {
                 try {
                     DateFormat parser = new SimpleDateFormat(datePattern);

You may use the attached file for regression testing purposes.

Original issue reported on code.google.com by gdbent...@gmail.com on 9 Jul 2013 at 4:20

Attachments:

• 31233852.JPG