mat2

About mat2

From Debian's package description

Metadata consist of information that characterizes data. Metadata are used to provide documentation for data products. In essence, metadata answer who, what, when, where, why, and how about every facet of the data that are being documented.

Metadata within a file can tell a lot about you. Cameras record data about when a picture was taken and what camera was used. Office documents like PDF or Office automatically adds author and company information to documents and spreadsheets.

Maybe you don't want to disclose those information.

mat2 only removes metadata from your files, it does not anonymise their content, nor can it handle watermarking, steganography, or any too custom metadata field/system.

If you really want to be anonymous, use file formats that do not contain any metadata, or better: use plain-text.

Formats supported to some extent are:

• Audio Interchange File Format (.aiff)
• Audio Video Interleave (.avi)
• Electronic Publication (.epub)
• Free Lossless Audio Codec (.flac)
• Graphics Interchange Format (.gif)
• High Efficiency Image Format (.heic, .heif)
• Hypertext Markup Language (.html, .xhtml)
• Portable Network Graphics (PNG)
• JPEG (.jpeg, .jpg, ...)
• MPEG Audio (.mp3, .mp2, .mp1, .mpa)
• MPEG-4 (.mp4)
• Office Openxml (.docx, .pptx, .xlsx, ...)
• Ogg Vorbis (.ogg)
• Open Document (.odt, .odx, .ods, ...)
• Portable Document Fileformat (.pdf)
• Portable Pixmap Format (.ppm)
• Scalable Vector Graphics (.svg)
• Tape ARchive (.tar, .tar.bz2, .tar.gz, .tar.zx)
• Torrent (.torrent)
• Waveform Audio (.wav)
• Windows Media Video (.wmv)
• ZIP (.zip)

mat2 provides a command line tool and a graphical user interfaces via a service menu for Dolphin, the default file manager of KDE. Besides, it recommends metadata-cleaner, a GTK app for viewing and cleaning metadata of files.

From Debian's description of the mat2 package, under that package's license.