ruminant 0.0.15

Recursive metadata extraction tool

Ruminant is a recursive metadata extraction tool.

What does it do?

Ruminant takes a file as an input and spits out a huge json object that contains all the metadata it extracted from the file. This is done recursively, e.g. by running ruminant again on each file inside a zip file.

Why the name?

To quote Wikipedia: Ruminants are herbivorous grazing or browsing artiodactyls [...]. The process of rechewing the cud to further break down plant matter and stimulate digestion is called rumination. The word "ruminant" comes from the Latin ruminare, which means "to chew over again".

This tool behaves similarly as extracted blobs themselves can be "chewed over again" (the main entrypoint is literally called chew()) in order to recursively extract metadata.

What can it process?

Ruminant is still in early alpha but it can already process the following file types:

• ZIP files
• PDF files
• JPEG files
  • EXIF metadata
  • XMP metadata
  • ICC profiles
  • IPTC metadata (I hate you for that one Adobe)
  • Adobe-specific metadata in APP14
  • MPF APP2 segments
• PNG files
  • EXIF metadata
• TIFF files
  • EXIF metadata (EXIF metadata is literally stored in a TIFF file)
  • DNG files
• ISO files
  • MP4 files
  • AVIF files
  • HEIF/HEIC stuff
  • XMP metadata
  • AVC1 x264 banners
  • all of the DRM stuff that Netflix puts in their streams
    • CENC
    • PlayReady
    • Widevine
  • SEFT metadata
• ICC profiles
  • EP0763801A2 extension
• TrueType fonts
• RIFF files
  • WebP
  • WAV
• GIF files
• EBML files
  • Matroska
    • WebM
• Ogg files
  • Opus metadata
  • Theora metadata
  • Vorbis metadata
• FLAC files
• DER data
  • X509 certificates
  • PEM files
• GZIP streams
• BZIP2 streams
• TAR files
  • USTAR to be precise
• PGP stuff
• ID3v2 tags
• MPEG-TS
• MakerNotes
  • Fuji
  • Sony
  • Google HDR+

How do I install it?

Run pip3 install ruminant. Alternatively, you can also run python3 -m build in the source tree, followed by pip3 install dist/*.whl.

How do I use it?

The most basic usage would be ruminant <file> in order to process the file and output all metadata.

Each time a blob is passed to chew(), it gets assigned a new unique ID that is stored in the "blob-id" field in its JSON object. These blobs can be extracted with ruminant <file> --extract <ID> <file name>. The --extract option can also be shortened to -e and can be repeated multiple times.

Not specifying a file means that it reads from -, which is the standard input. You can also explicitly pass - as the file.

The --walk or -w option enables a binwalk-like mode where ruminant tries to parse a file and increments the start offset by one until it can correctly parse something. This is done until the end of the file.

This is a valid complex command: ruminant -e 2 foo.jpeg - --extract 5 bar.bin -e 0 all.zip

(Yes, you could abuse ruminant to copy files by running function cp() { ruminant --extract 0 $2 $1 } in bash and then using the function as cp.)

You can also specify --extract-all in order to extract all blobs to the "blobs" directory.

Ruminant can't parse xyz

Feel free to send me a sample so I can add a parser for it :)