TIFFer

A library for parsing TIFF format.
The main purpose of this library is reading meta-data from TIFF files.

Description

This library supports reading and parsing TIFF tags and their values.

Decoding of image formats is not supported by this library.
Writing and encoding data is also not a part of this library.

I. Tags.

This library supports tags of following categories:

• Baseline tags
  (of the TIFF 6.0 Specification)

• Extension tags
  (including but not limited to)

  • XMP

• Private tags
  (including but not limited to)

  • Alias Sketchbook Pro
  • DNG
  • GDAL
  • GeoTIFF
  • HylaFAX
  • ICC Profile
  • Intergraph Application
  • IPTC
  • Molecular Dynamics GEL
  • Oce
  • Wang Annotation

• Private IFD tags
  (including but not limited to)

  • EXIF
  • GPS
  • Interoperability

II. Sub-IFD Feature.

The library is able to read tags stored in so called Sub-IFDs which is really a bit of a "hack" of the TIFF encoding scheme. TIFF format was designed to support only the flat layout of IFDs. Sub-IFDs in this library can be accessed via the SubIFD field of the Directory Entry (Tag). A couple of usage examples of the library can be viewed in the example folder.

III. Additional Features.

• Human-readable tag names are automatically used for well known tags.

• Directory Entries (Tags) may be listed not only using the official way, i.e. using the pointer to the next IFD or Sub-IFD, but also using associated lists (arrays / maps) storing tags by their numbers and names.

• Simple statistics is gathered about all tags used in the TIFF document for each IFD and Sub-IFD. It includes:

  • Number of known tags
  • Number of unknown tags
  • Number of tags with a registered type rule
  • Number of tags which have no type rule

Links

• TIFF Tag Reference at AWARE SYSTEMS
  https://www.awaresystems.be/imaging/tiff/tifftags.html

• TIFF 6.0 Specification (Revision 6.0 Final — June 3, 1992)
  https://developer.adobe.com/content/dam/udp/en/open/standards/tiff/TIFF6.pdf

History

TIFF format was developed by Aldus Corporation. At this moment, in the year 2023, the owner of this technology is Adobe Inc., who bought Aldus Corporation in September 1994. More information about TIFF format can be found in Wikipedia: https://en.wikipedia.org/wiki/TIFF

Notes

There are some mismatches between Golang's data types and TIFF format data types. First of all, it concerns the Rational data types. More information can be found in the comments of the basic-types.go file.