A machine-readable format

• Want to do at least three things with TV listings: download them, filter them and print them.
• Need a common machine-readable format.

Why XML?

• Because it's kewl
• Because I don't have to write a parser
• DTD unambiguously defines the file format
• Validation using nsgmls
• So a good base for exchanging code with others.

I looked for established formats for TV listings, but none was appropriate. They all had too few features or too much cruft.

• Tend to be one channel only, but for the viewer channel is almost irrelevant and impedes sorting.
• Correspond too closely to weird internal database formats (eg Press Association) or to one particular output format (the German channel SAT.1 distributes listings with the attribute 'von' to say whether to write 'Wiederholung von' or 'Wiederholung vom'.
• Inch-thick standards full of digital TV classifications and few concrete examples.

So I decided to make my own format. A simple example is on the front of the XMLTV web page. The aims for the format were:

• Represent listings from the viewer's perspective, not the broadcaster's.
• Include information you'd find in a printed TV guide.
• Include information needed for particular applications, as they appear.
• Include all information fetched from the Ananova site (no details thrown away).
• Simple in the simple case. This means making almost everything optional.

The present format has many more features than the very first version. Notably the storage of channels and channel names following RFC 2838. It is about halfway evolved to the final version, there are still things to tidy and generalize.

• Data should go in elements and metadata in attributes. For XMLTV the metadata is broadcast details, a programme is 'the same' in some way irrespective of when it is broadcast.
• Tried not to have multiple forms of the same information, so made ordering significant. For example when more than one title is given the first title is more important somehow. Programmes are listed in the same order as printing.
• All human-readable data has a language given, so mixed-language no problem
• Don't use ID/IDREF for channels because the weird RFC2838 names are optional.