GZip-kb Module

1 Introduction

The GZIP-kb module recognizes and validates the Gzip (GNU zip) format. [GZip].

The module is invoked by the:

    jhove ... -m GZIP-kb ...
  

command line option.

The GZIP-kb module recognizes and validates GZip version 4.3. It also supports multiple member GZip files. This module uses the JWAT library for GZip parsing.

This module doesn't have configurable parameters.

2 Coverage

The GZIP-kb module recognizes and validates the following public profiles:

• RFC 1952

3 Well-Formedness

The GZip module checks well-formedness.

4 Validity

The following criteria must be met by a GZip file for JHOVE to consider it valid:

• The file is well-formed. In GZIP-kb module the well-formedness and validity are equivalent.

5 Representation Information

The MIME type is reported as: application/gzip [RFC 6713]. Application/x-gzip is also supported

In addition to the standard JHOVE representation information, the following GZip-specific properties are reported:

• Property "GzipEntryProperties"
  • Property "Is non compliant" of type STRING
  • Property "Offset value" of type STRING
  • Property "GZip entry name" of type STRING
  • Property "GZip entry comment" of type STRING
  • Property "GZip entry date" of type STRING
  • Property "GZip entry compression method" of type STRING
  • Property "GZip entry operating system" of type STRING
  • Property "GZip entry header crc16" of type STRING
  • Property "GZip entry crc32" of type STRING
  • Property "GZip entry extracted size (ISIZE)" of type STRING
  • Property "GZip entry (computed) uncompressed size, in bytes" of type STRING
  • Property "GZip entry (computed) compressed size, in bytes" of type STRING
  • Property "GZip entry (computed) compression ratio" of type STRING

6 Additional Module Properties

• Nominal file extension: .gz