Rotating capture system with HDHomeRun

This is Carlos' quick and dirty solution to have a grid with captions from all stations using a few tuners, obviously by rotating them to cover all channels.

File directories:

  • /bin/ → Scripts
  • /channels/ → Channels, each file being a channel. If name starts with a C then it's cable, if it's a B it's broadcast, anything else is ignored.
  • /tuners/ → One file per tuner, with this naming
    $devicetype-$tunertype-$masterorregular-$deviceid-$tunernumber
    where
    $devicetype is always HDR (for now only HDHomeRun is supported)
    $tunertype is USC (US-cable) or USB (US-broadcast)
    $masterorregular is M or R, if M then this tuner will be used to scan for channels by the chanscan script that populates the /channels/ directory
    $deviceid is the device ID. For HDHomeRun is returned by hdhomerun_config
    $tunernumber is the number within the device, so for a device with 3 tuners it's 0-2

Scripts:

  • /bin/tuner_scan → Discover HDHomeRun devices and features, build contents of /tuners/
  • /bin/channel_scan → Scan for channels, build contents of /channels/
  • /bin/cc_boot → Starts one capture process per tuner
  • /bin/cc_capture → Using one of the tuners, capture data from a channel in round-robin

The /channels/ directory contains one file per channel. When a channel is being recorded its file must be renamed to $name.inuse. When done, touched, then renamed back to $name.free. If a process attempts to rename a channel file and fails it must assume that some other process picked up that channel and must continue to the next one.

The cc_capture script always reads contents of /channels/ and picks the oldest file that is free (meaning there isn't another process capturing it).

Done:

  • Create system user (captions), copy public key
  • Edit sudoers

To-do:

  • Create tuner_scan
  • Create channel_scan
  • Create cc_capture
  • Create cc_boot