How to Manipulate EXIF information on MacOSX.

How can we manipulate EXIF information on MacOSX? I think it is the easiest way to use exiftool, that is provided by Mac ports.

At first, we have to install exiftool by using Mac ports.

1. sudo port selfupdate
2. sudo port upgrade outdated
3. sudo port install p5-image-exiftool

Then check the EXIF information as below:

• exiftool <JPEG_FILE>

If you prefere specific language, you can give additional option like following:

• exiftool -lang ja <JPEG_FILE> # for Japanese output

To manipulate EXIF data, we have to specify exact EXIF IDs. To get the IDs, check out the information again as follows:

• exiftool -s <JPEG_FILE>

It shows real IDs of EXIF specification.

Then, for example, we can specify to modify "CreateDate" like:

• exiftool -CreateDate <JPEG_FILE>   # Check the current value.
  Create Date : 2012:03:29 12:56:00
• exiftool -CreateDate="1234:05:06 07:08:09" <JPEG_FILE>   # Set the new value
  
• exiftool -CreateDate="" <JPEG_FILE>   # Delete the value
  
• 
  
• exiftool -GPSAltitude="" -GPSDateTime="" -GPSLatitude="" -GPSLongitude="" -GPSVersionID="" -GPSLatitudeRef="" -GPSLongitudeRef="" -GPSAltitudeRef="" -GPSTimeStamp="" -GPSProcessingMethod="" -GPSDateStamp="" -GPSDateTime="" <JPEG_FILE>   # Delete all GPS data

Furthermore, if we want to know where the information come from, use "-G" option.

• exiftool -G <JPEG_FILE>

Here are many TAGs for EXIF.