Page 174 - ITU Journal, ICT Discoveries, Volume 3, No. 1, June 2020 Special issue: The future of video and immersive media

ITU Journal: ICT Discoveries, Vol. 3(1), June 2020

The EXIF tag structure is borrowed from tagged image file format (TIFF) files. On several image specific
properties, there is a large overlap between the tags defined in the TIFF, EXIF, tagged image file
format/electronic photography (TIFF/EP), and design rule for camera file (DCF) standards. For descriptive
metadata, there is an overlap between EXIF, International Press Telecommunications Council (IPTC)
information interchange model and extensible metadata platform (XMP) info, which can also be embedded in
a JPEG file. The Metadata Working Group has guidelines on mapping tags between these standards.
When EXIF is employed for JPEG files, the EXIF data are stored in one of JPEG's defined utility application
segments, the APP1 (segment marker 0xFFE1), which in effect holds an entire TIFF file.

4.5 Web HTML
This application proved to be one of the killer applications in the success of JPEG: high quality photographic
type images on web pages. Nevertheless, the results of development of a videotex photographic mode as
shown in section 4.1.3 are very similar to this application, so the results from there could be easily adopted.
As early as February 1993, JPEG was already included in the first web browser in the famous Mosaic (Fig. 15).
Note that this was only 6 months after the formal approval of the JPEG draft by CCITT and one year before that
in ISO/IEC JTC1. So, most likely, the IJG code was taken.

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