exiv2:tldr:b1a90

The command "exiv2 -d a ${filename}" is a command-line invocation of the exiv2 program. Exiv2 is a command-line tool used for manipulating metadata in image files.

Here's the breakdown of the command:

• "exiv2": This is the name of the program that is being invoked. It is followed by various options and arguments.
• "-d a": This option stands for "delete all metadata". When this option is used, all the metadata (such as EXIF data, IPTC data, etc.) present in the image file will be removed.
• "${filename}": This is a placeholder for the actual name of the file you want to work with. You should replace "${filename}" with the specific name of the image file on which you want to perform the metadata deletion.

So, when you run this command, exiv2 will remove all metadata present in the specified image file.