[mythtvnz] The use of CRIDs in MHEG and EIT streams

[Solor Vox]

On 1 May 2010 10:33, Steven Ellis <steven at openmedia.co.nz> wrote:
> Thought it would be worth while splitting the technical discussion of the
> CRID data from the current grabber thread until we have the details worked
> out.
> I've managed to dig out the following references
> CRID format
> CRIDs carried in SI may be defined in such a way that the Scheme and
> Authority parts are carried once only if they are common to a group of
> CRIDs. However the format for CRIDs passed across the MHEG PVR API in any of
> the following Resident Program calls shall include the Scheme and Authority
> parts in all cases.
> A CRID that does not include an instance identifier shall be in the format:
> Scheme + Authority + Unique Identifier
> A CRID that includes an Instance Identifier shall be in the format:
> Scheme + Authority + Unique Identifier + # + Instance Identifier
> Examples of CRIDs with and without Instance Identifiers follow:
> crid://company.tv/123df5
> crid://broadcaster.com/hef5w#e1
> As specified by [DTG DTR] CRIDs carried in SI are case insensitive. However,
> MHEG-5 operations on strings are case sensitive. So:
> • the following Resident Programs shall be case preserving • operations
> relative to broadcast SI shall be case insensitive
>
> Basically the myFreeview PVRs can book programs by either series ID or
> episode. The EIT stream on DTH also contains these crid fields so the PVR
> can match the booking to the correct program.
> One other benefit is that if they start broadcasting EIT Actual then the PVR
> should realise when a program is delayed and re-schedule accordingly.
> You can find the TV Anytime reference on CRIDs here
>  * http://www.rfc-archive.org/getrfc.php?rfc=4078
> Haven't found any reference on how a CRID is mapped to a particular show, of
> if it is program unique or program+network unique.
> Steve