2.3 png-boilerplate: Show or remove the boilerplate in .png files

Sometimes PNG image files contain copyright and license notices. Authors put these notices in comments section so that when the file propagates, the license propagates too. The png-boilerplate command is for showing or removing comments in PNG files. It is normally executed in this fashion:

$ licensing png-boilerplate foo.png

This example will result in the comment section of the png file being displayed. The PNG file format allows for many named text sections in the file. The png-boilerplate command only operates on the first text section named "Comment".

2.3.1 Removing comments from a PNG file

To remove the boilerplate from a PNG file, use the --remove option:

$ licensing png-boilerplate --remove foo.png

This command will modify the first text section named "Comment" in the PNG file foo.png so that it contains an empty string. This is slightly different than removing the text section entirely.

When removing comments, a .bak backup file is created by default. To prevent this behaviour use the --no-backup option.