Autor: Dave Pickles
TV-Anytime is the name given to a set of technologies which aim to simplify the process of recording and replaying broadcast content. The standards are published by ETSI and are available without cost from www.etsi.org. The main standard is ETSI TS 102 323.
Letztes Update 08/2013
In the UK a subset of the TV-Anytime specification is broadcast on the DTV service under the trade name "FreeView Plus". This plugin is written for the UK version, has been tested on New Zealand DVB-S and is believed to be compatible with the NorDig standard used in Scandanavian countries plus Eire. It should also work with the full specification (untested).
in which <DNS name> is a registered internet domain name (RFC 1034) and <data> is a free-format string. The <DNS Name> section relates to the content provider (TV channel or company), and the <data> section to the programme.
CRIDs are transmitted in the EIT as Content Identifier Descriptors, with descriptor ID 0x76. To save bandwith only the <data> section is sent, the <DNS Name> part is taken from the Default Authority Descriptor in the SDT, and the crid:// is assumed.
A programme may have up to three CRIDs in its EPG entry. One identifies the specific item of content which is being broadcast, while another identifies a series of programmes which this item belongs to. The third type includes the CRIDs of 'suggested' events which the viewer might be interested in. In FreeView Plus these CRIDs have crid_type values 0x31 0x32 and 0x33 respectively (TV-Anytime uses values 0x01 - 0x03).
To give an example, the programme "Torchwood" broadcast on channel BBC2 at 21:00 on 2008-01-16 had item CRID '54BXLC' and series CRID 'KCJ00C'. When the same programme was repeated the following day on channel BBC3, the item CRID remained the same but the series CRID was 'KCJ12C'. Meanwhile the episode broadcast on BBC2 one week later on 2008-01-24 had CRID '54BXLD' but the same series as the previous week. Hence it is possible for a PVR to record an entire series by using the series CRID, or to find an alternative broadcast for an individual item if there is a clash with another recording.
The use of the 'Accurate Recording' feature is described in README-vps.
The plugin captures CRID data continuously, beginning 5 minutes after VDR startup. A maintenance task runs every 24 hours at a time set by the '-u' parameter or in VDR's OSD (default 03:00) which:
- Checks for new manually-created timers and adds series links for them.
- Checks each series link to see if any new events have been added to the EPG in the same series. If so then timers are added for them.
- Checks for timer clashes and suggests possible alternative recording times.
- Checks that the event being recorded by each timer is the same as when the timer was set (ie that the EPG has not changed in the meantime)
- Flags any split events (eg a long programme with a news summary in the middle). At present a manual check is needed that all parts of the programme are set to be recorded.
- Optionally sends a mail report listing new timers which have been automatically created, any timer clash warnings, and a complete list of timers and any suggestions for them.
The plugin takes the following parameters:
-l n --lifetime=n Lifetime of new timers (default 99) -m addr --mailaddr=addr Address to send mail report -p n --priority=n Priority of new timers (default 99) -s n --serieslifetime=n Days to remember a series after the last event (default 30) -u HH:MM --updatetime=HH:MM Time to update series links (default 03:00)
The plugin logs activity through the VDR syslog, unless the -m parameter is set in which case only errors go to syslog and a report is emailed to the given address daily.
The plugin has an SVDRP interface which is mainly used for debugging, but could be used to interface with other applications. The commands are:
LLOG Print the pending log report
LSTL Print the series links list
LSTS Print the 'suggested' events list
LSTY Print the CRIDs for each event
LSTZ Print the Default Authority data for each channel
STOP Start and stop CRID data capture STRT
UPDT Trigger an update of the series links.
Points to remember:
- Not all channels on UK Freeview have CRIDs in the EPG. Some radio channels have item CRIDs but none have series CRIDs.
- Different programme providers have different ideas of what constitutes a 'series'.
- The timer creation process is very simplistic; it doesn't check for timer clashes, and selects the first physical entry in the EPG (which may not be the prime broadcast of the programme).
- A series link is created for every timer whether you want one or not.
- This plugin has not been tested with multiple tuner cards or with mixed DVB-T and DVB-S setups.
- The 'suggested' events list may have CRIDs which do not appear in the events list.
The plugin is compatible with VDR version >= 1.7.19. The patch version will work with VDR 1.6.
Although I use this software day-to-day on my VDR installation, this is Beta-quality code - USE AT YOUR OWN RISK!!