JHOVE2 is open source software for characterization of digital objects. Characterization captures the information about a digital object that describes that object's significant technical properties. For example, for a digital image file, JHOVE2 can identify the precise file format, as well as the salient technical properties of the file, such as resolution, bit-depth, and color-space. Capturing this information supports digital preservation analysis and decision making.
JHOVE2 analyzes digital objects with these questions:
- What is it? (Identification)
Identification is the process of determining the format of a digital object on the basis of both internal (e.g. magic number) and external (e.g. file extension) information.
- What about it? (Feature extraction)
Feature extraction is the process of reporting the properties of a digital object which are significant to preservation planning and action.
- What is it, really? (Validation)
Validation is the process of determining the level of conformance of a digital object to the rules defined by the authoritative specification of the object's format.
- So what? (Assessment)
Assessment is the process of determining the level of acceptability of a digital object for a specific purpose on the basis of locally-defined policy rules.
JHOVE2 supports the validation and feature extraction of the following format families and specific format subtypes:
- ICC color profile
- JPEG 2000
- JP2 (ISO/IEC 15444-1) and JPX (ISO/IEC 15444-2) profiles
- PDF 1 - 1.7, ISO 32000-1, PDF/X-1 (ISO 15930-1), PDF/X-1 (ISO 15920-1), \-1a (ISO 15930-4), \-2 (ISO 15930-5), \-3 (ISO 15930-6), PDF/A-1 (ISO 19005-1)
- TIFF 4 - 6, Class B, F, G, P, R, and Y, TIFF/EP (ISO 12234-2), TIFF-FX, TIFF/IT (ISO 12639), Exif (JEITA CP-3451), GeoTIFF, Digital Negative (DNG), RFC 1314
- UTF-8 encoded text
- ASCII (ANSI X3.4)
- WAVE audio
- Broadcast Wave Format (EBU N22-1997)
Jhove2 is run at the command line. There are also mechanisms for extending the number of supported file types.