Real world EIT data

I run a MythTV box with both analog (dual tuner  Hauppauge PVR-500) and digital (dual tuner HD Homerun) capture devices.

For reasons peculiar to my setup I use Schedules Direct ($25/yr) for program info for the analog side but not on the digital side.  For that I pull EIT data from the digital stream itself, which means it’s free.

At this point the die-hard geek+frugalista asks:  is the $25/yr Schedules Direct feed worth the money?

Consider the following results:


The top is the data from Schedules Direct.    The description is full and it is categorized.  All that is nice, but the killer info is the original airdate and rerun flag.  At least I think the rerun info is a transmitted flag and not derived from the original airdate.  Not shown here is the series and episode ID flags which are created by Zap2It or whomever SD licenses the data from.

This enables you to record only new (or new-to-you) shows as you like.    Since the EIT lacks that data if you make a quasi-Season Pass type request you will get all eps, even repeats.

Catching re-runs may seem like no big deal, but it has downsides.  It is up to you to decide whether or not these downsides are worth $25/yr.

  1. you have to identify the reruns before you can deal with them.  MythTV does a good job of making thumbnails from which you can recognize reruns without actually viewing them.
  2. if you have a max number of episodes to keep then reruns will throw a wrench into your plans.  It is conceivable that reruns (or even rebroadcasts of the same rerun) will fill all your N slots.  Consider what happens if you have a 5-ep config for whatever show and you are waiting for a season finale, but the channel runs a marathon of eps prior to or after the finale.  Your finale might not get recorded or get recorded then bumped off before you saw it, depending on your config.  Badness.
  3. taping previously-seen shows has an opportunity cost;  the tuner is busy taping the unwanted show so a conflict can cause a wanted show to be missed.  This would be most troublesome in a single-tuner setups.

Note:  it appears that EIT is a minimal, subset of  PSIP definition.  The EIT (and ETT, below) is combined by your front-end to make an Electronic Program Guide.

Per this document (pdf):

Each instance of an EIT covers a three-hour time span, and provides the following
information for each programming source:
• Event start time
• Event duration
• Event title
• A pointer to optional descriptive text for the event  {ETT — see below.  fratermus}
• Program content advisory data (optional, but if present it must go here)
• Caption service data (sometimes optional, but when present must go here)
• Audio service descriptor (required if audio is present)

So the broadcaster could be sending additional info in the Extended Text Table but I don’t seem to be getting any of that.

Also, the EIT data may not be contiguous, if that’s the right word.  Consider this:


Note the big jump between the 12:30pm and 9pm start times.  I don’t see this all the time but I guess it happens.


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