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noggin13,884 posts since 26 Jun 2001
Does anyone have to hand the ANC packet structure for Invisodt. Or know where I can obtain?


http://dpp-assets.s3.amazonaws.com/wp-content/uploads/specs/itv/ProgrammeDeliverySpecificationLiveITV.pdf

Quote:

Out of Vision Cue Dots (Mandated Requirement)
The use of Out of Vision Cue Dots on all live programmes supplied to ITV is now a mandatory requirement. The Out of Vision Cue Dot triggers should be carried within the VANC as OP47 data packets on line 15 (578) using only ITV approved equipment.


OP47 appears to be a standard for carrying teletext/subtitles in VANC? I guess Invisidots are part of this?

https://downloads.axon.tv/downloads/1378106/AN2012-11%20Cue%20encoding%20HSI21.pdf Seems to suggest that teletext packet 31 might be used? But this is a very brief skim reading.
http://www.microvideo.co.uk/wp-content/uploads/2013/08/Data-Management-in-Broadcast.pdf

So it looks like Invisidots may well be carried in a form of a teletext data stream carried in VANC? (OP47 being the teletext-in-VANC standard?)

I have no idea if Invisidot is proprietary or standardised? I've seen reference to an Invisidot 'heart beat' so there may be a requirement to send 'I'm still here' type data to confirm the invisidot link is still valid?
badgerbeater2 posts since 23 Oct 2018 new member
Thanks Noggin.
You're correct Axon does appear to insert the Invisdot data "somewhere" within the the Ancillary data using Operational Practice-47.
I was hoping I could find specifically what data it was carrying and where. It looks like ITV specify it on line 15 but the AXON manual link that you attached implies you can put it on any line you like.
At this stage I'm only interested in knowing which bit or bits change as its turned on or off (although it'd be nice to know if it carries any other flags too). With a Tektronix Scope, an Axon card and on an ITV job I'm sure I could figure it out in a few minutes. Unfortunately I have neither at my disposal.
noggin13,884 posts since 26 Jun 2001
Thanks Noggin.
You're correct Axon does appear to insert the Invisdot data "somewhere" within the the Ancillary data using Operational Practice-47.
I was hoping I could find specifically what data it was carrying and where. It looks like ITV specify it on line 15 but the AXON manual link that you attached implies you can put it on any line you like.
At this stage I'm only interested in knowing which bit or bits change as its turned on or off (although it'd be nice to know if it carries any other flags too). With a Tektronix Scope, an Axon card and on an ITV job I'm sure I could figure it out in a few minutes. Unfortunately I have neither at my disposal.


Looks like it might be carried in Packet 31 of a WST stream?