ExifTool on Source Code: Source Code, Structure and Building

Explore what is inside the ExifTool source repository, how to run it straight from the ZIP and how developers use the Image::ExifTool Perl library.

Source Code6 min read
ExifTool Source Code: Source Code, Structure and Building illustration

Choose the package for your operating system. Keep a backup of your files before changing metadata.

What the source repository is

The repository holds the complete Perl source of ExifTool: the command-line application and the Image::ExifTool library behind it. Official releases, documentation and the support forum are hosted on the developer's own website, the ExifTool documentation, while the repository gives developers a convenient way to browse history, compare versions and download the code as an archive.

Inside the source distribution

When you extract the source archive you will see a folder named Image-ExifTool-13.60 containing:

  • exiftool: the command-line script you run.
  • lib/Image/ExifTool.pm and the lib/Image/ExifTool/ folder: the modules that parse and write each file format and metadata standard.
  • t/: automated tests that check reading and writing behaviour.
  • html/: HTML documentation, including tag name tables.
  • config_files/: example configuration files for creating user-defined tags.
  • Makefile.PL, README and the change history.

Running ExifTool from source

You do not need to install anything to try the source version. Extract it and run the script directly:

$ cd Image-ExifTool-13.60
$ ./exiftool -ver
$ ./exiftool ~/Pictures/photo.jpg

On Windows with a Perl interpreter installed, prefix the commands with perl:

$ cd Image-ExifTool-13.60
$ perl exiftool -ver

The script finds its library in the neighbouring lib folder, so keep the folder structure intact.

Building and installing

To install ExifTool system-wide from source on macOS or Linux, use the standard Perl module process. Running the tests is optional but confirms everything works on your system:

$ perl Makefile.PL
$ make
$ make test
$ sudo make install

This places exiftool in your PATH and installs the library where Perl can find it. Alternatively, copy the script and the lib folder together into a directory such as /usr/local/bin.

If your Linux distribution already provides ExifTool through its package manager, installing from source as well can leave you with two versions. Run which exiftool to see which one your shell uses.

Using Image::ExifTool in Perl

Developers working in Perl can call the library directly instead of launching the command-line tool. A minimal script looks like this:

use Image::ExifTool qw(:Public);
my $info = ImageInfo('photo.jpg');
print "$_ => $$info{$_}\n" for sort keys %$info;

Programs written in other languages usually run the exiftool command and parse its -json output. For high-volume work, the -stay_open option keeps one ExifTool process running and accepts commands continuously, avoiding the start-up cost of launching it for every file.

Reporting issues responsibly

If you believe you have found a bug, first check that you are using the newest version with exiftool -ver. Then prepare a short description, the exact command and, if possible, a sample file that reproduces the problem. The developer's official forum on the ExifTool documentation is the established place for support questions.

Ready to start? Grab the source package from our download section, or learn the basics in the ExifTool beginner's guide.