noggin's posts, page 60

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NG
noggin Founding member

PromoSmart: Personalised trails on live BBC channels

all new Phil posted:
Pete posted:
noggin posted:

(The DVB standard is designed for local advert insertion at DVB-T/T2 transmitter sites or DVB-C cable head ends that are fed by satellite. It can also be used for triggering local news insertion I believe)


Wouldn't this save a fair whack for ITV's distribution costs?

I remember suggesting this over on Digitalspew when it was first announced but I just got loads of reasons why it wouldn’t work. Glad to see that it potentially could.


It stops you being able to statmux though - so it's not without new limitations. UK DVB-T and T2 stuff (apart possibly from local TV) is statmuxed to maximise encoding efficiency. If you need to replace content at the DVB level, you can't statmux, so you are then either dropping quality or increasing bitrate of your CBR system to mitigate.

Remember this is how BBC One English regional news effectively worked on DVB-T in the early days of regional opting on DVB-T (without the automatic signalling) - and this meant BBC One was CBR at around 5.8Mbs with BBC Two, Three/CBBC, News 24 statmuxed with each other (but not with BBC One). (Think Parliament and possibly BBC Four/CBeebies were still on a different mux at this point?)

The limitations of having to run CBR for channels that use 'local replacement' mean that it's not really a go-er here for DVB-T/DVB-T2 'drop ins' here.
NG
noggin Founding member

PromoSmart: Personalised trails on live BBC channels

Pete posted:
noggin posted:

(The DVB standard is designed for local advert insertion at DVB-T/T2 transmitter sites or DVB-C cable head ends that are fed by satellite. It can also be used for triggering local news insertion I believe)


Wouldn't this save a fair whack for ITV's distribution costs?


Not really - as it would mean they couldn't be statmuxed.
NG
noggin Founding member

PromoSmart: Personalised trails on live BBC channels

Neil Jones posted:
AFAIK Adsmart only works if you watch in real time OR play back in real time. So if you suspect you've seen an adsmart advert, you can wind it back and you should be able to see what advert was covered up.

https://www.adsmartfromsky.co.uk/faqs/ is quite interesting, particularly the question about recorded content.


Yes - the bit about advertisers being able to supply their own household information is interesting - it presumably means they can target people they know about?

The charging structure is interesting too.
NG
noggin Founding member

GMB & This Morning to be extended-Official

Interesting that ITV are happy to drop a Salford-based show. This means their 0600-1330 daytime output (7.5 hours) 5 days a week is all from London. That's a lot of London output. I suspect Ofcom will be looking at where their out-of-London production is?
Last edited by noggin on 12 November 2019 11:42am
NG
noggin Founding member

Half Frame Width HD Video Backhaul

harshy posted:
I don’t understand if BT are sending quad feeds in UHD for 4hd pictures does that mean bt aren’t broadcasting true UHD pictures?


No - it's perfectly routine to produce in Quad HD and until 2160p50 h.265 broadcast encoders and decoders were widespread, 4 x 1920x1080p50 h.264 streams were sometimes backhauled over fibre or satellite. You have to work very hard to ensure the 4 streams say in sync with each other - otherwise you will see 1/4 of the picture cut early/late compared to the others for instance.

You effectively send a single UHD picture as 4 x HD streams (1080p50 not 1080i25)

Also - in UHD production almost no studios or OB trucks use 2160p50 12G-SDI for interconnects, they either use Quad 2022-6/7 (3G-SDI 1920x1080 over IP) or 2110 (2160p50 or Quad 1080p50 elementary streams over IP), or Quad 3G-SDI (4 x 1920x1080p50 in either Quadrant or 2SI modes) In fact a lot of vision mixers and servers like EVS were upgraded to UHD with relatively few modifications (they took in one UHD signal via 4 HD inputs, and output one UHD signal as 4 HD outputs - you quartered the number of inputs and outputs - but didn't have to totally re-engineer your product...)

1920 x 2= 3840
1080 x 2 = 1080

So 4 x 1080p50 streams = 1x 2160p50 - and if you keep them all in sync you're fine.

In Quad 3G-SDI - Quadrant mode splits the picture into 4 quarters, 2SI mode switches the feeds in small groups of pixels (it isn't 2x2 pixels but that's a good way of thinking about it) so with 2SI you get 4 x full size 16:9 pictures (rather than quarter screen portions) (Ironically this was what the BBC and Phiips/BTS did in the late 80s when they recorded 1440x1152 Eureka 1250 HD as 4 x SD 720x576 digital streams onto D1 VTRs. What goes around comes around - the BBC system was very similar to 2SI, the Phiilps/BTS system was Quadrant)

HOWEVER - as thegeek mentioned - h.265 2160p50 encoders are now available and so you can backhaul a UHD video stream (whether produced in Quad 3G or 2160p50 native) as a single stream. As a by product - if you are doing HD remote production (i.e. not UHD) you can backhaul 4 camera outputs (for cutting back at base rather than on-site, or multiple event streams) as 4 x 1080p50 streams as a Quad Split in 1 x 2160p50 stream, rather than backhauling 4 x 1080p50 h.264 or h.265 streams - and by keeping them as a single 2160p50 stream you have everything nice and in sync (particularly relevant for remote camera feeds)
Last edited by noggin on 12 November 2019 11:32am - 2 times in total
UKnews, thegeek and bilky asko gave kudos
NG
noggin Founding member

Half Frame Width HD Video Backhaul

thegeek posted:

You can also use H265 to send four individual cameras as if it were a single 2160p image (essentially a quad split), and use it in a remote production scenario, producing an HD programme - thus using fewer encoders and satellite space than using one per camera.


And the quad split approach ensures the 4 feeds do stay in sync.
NG
noggin Founding member

Half Frame Width HD Video Backhaul

Rkolsen posted:
noggin posted:
Rkolsen posted:

Satellite providers can reencode to fit their distribution platform however they cannot change anything that would alter how it’s displayed - if it’s 1920x1080i they’d have to transmit it at the same quality of the station. The same goes for cable which up until a while you could plug in a tv without a box and tune to the stations OTA channel number and get the channel. Now that’s all encoded. Like satellite they can’t distort or change the signal.


They were certainly horizontal down-sampling in the MPEG2 days https://www.engadget.com/2007/01/11/the-engadget-hd-interview-directvs-cto-re-hd-lite/

HD-Lite was the name that people who didn't like it christened it. I wasn't aware of any legislation in the US that dictated that broadcast resolution has to be maintained 1:1.


HD Lite was never used on broadcast, OTA channels.



Yep - I was clear to use the word platforms and never suggested that HD Lite was used for ATSC platforms (though ATSC QAM cable operators do resolution conversion, and some affiliates of '1080i' networks broadcast at 720p on their ATSC 8VSB OTA transmissions I believe - some PBS stations for example)

HD Lite was particularly a thing for satellite operators who had to cope with large numbers of local regional affiliates on their platform, and didn't have the bandwidth to carry them - and all the other national channels - at full quality. HD Lite was their solution to getting bitrates down...

Quote:

I'm going by one of the comments in a Comcast forum from an employee. Also, since my local Comcast headend (and most across the country) have moved to "enhanced HD" aka down converting all non broadcast channels to 1280x720p and encoding them in MPEG-4. They may have converted OTA to MPEG-4 but the resolution stands. I believe if Comcast and others could downsize broadcast affiliates to 720p, they could and would.


Yep - HD Lite was (and may still be) more of a satellite thing.

In the days when DVC Pro HD and HD Cam (1280x1080 and 1440x1080 respectively at i29.97) were often used in acquisition - there often wasn't much information between 1280 and 1920 horizontally anyway... However once HD Cam SR, XD Cam 422 HD etc. became widespread (and for operators using HD-D5 back in the day instead of HD Cam) there was good reason to keep to 1920. (DVC Pro HD in 720p is even worse - it's 960x720 at p59.94)
NG
noggin Founding member

Half Frame Width HD Video Backhaul

Rkolsen posted:
noggin posted:
Rkolsen posted:
Here the only standards used are 1920x1080 and 1280x720 and as it’s an NBC station it will be 1920x1080 (Fox and ABC are the only 720p only broadcasters). There used to be HD Lite on satellite where it was 1440x1080 and some cable companies in an effort to fit 100+ HD channels have downgraded the signals to 720p (but they cannot convert or manipulate broadcast channels on their system). The ATSC standard only supports those two for HD, but have been used for distribution. If there are multiple HD services the 1920x1080i may be downgraded to 1280x720p or SD widescreen, so those odd resolutions wouldn’t be transmittable.

Edit : However if they are using a DVE or resized for multiple boxes (not sure what it’s called when there are more than one video feed on air) it may not be noticeable.


Yep - it was Dish and/or DirecTV who use (or used) the lower horizontal resolution variants - as low as 1080x1080 I believe. People with modified receivers who could access the decrypted transport stream were able to analyse the video parameters ISTR. Things may have changed since then. AIUI the satellite platforms are allowed to re-encode the local broadcast channels they distribute - as they use h.264 rather than MPEG2 (which is still used OTA) for distribution these days ?

ATSC mandates (or kind of tried to) specific resolutions for OTA and cable - but the North American satellite operators can pretty much do what they like on their closed platforms.


Satellite providers can reencode to fit their distribution platform however they cannot change anything that would alter how it’s displayed - if it’s 1920x1080i they’d have to transmit it at the same quality of the station. The same goes for cable which up until a while you could plug in a tv without a box and tune to the stations OTA channel number and get the channel. Now that’s all encoded. Like satellite they can’t distort or change the signal.


They were certainly horizontal down-sampling in the MPEG2 days https://www.engadget.com/2007/01/11/the-engadget-hd-interview-directvs-cto-re-hd-lite/

HD-Lite was the name that people who didn't like it christened it. I wasn't aware of any legislation in the US that dictated that broadcast resolution has to be maintained 1:1.
NG
noggin Founding member

Half Frame Width HD Video Backhaul

Rkolsen posted:
noggin posted:
A number of US platforms use lower resolutions than 1920x1080 for emission (i.e. the final leg to the viewer) - with 1440x1080 (as BBC HD used to use), 1280x1080 and 1080x1080 all used I believe - so the resolution loss caused by a 50% horizontal squeeze may not be that huge.

DVC Pro HD - which was a widespread codec in use for production (as it's supported by pretty much every platform - FCP, Avid, Prem Pro, Quantel/GVG - and operating system) uses 1440x1080 in 1080i25 and 1280x1080 in 1080i29.97 too (the lower frame rate of 50Hz systems means you get a bit more resolution)

I've worked on shows where video screens are fed by 1/4 screen crops and zooms of a single quad split graphic source (rather than tying up 4 replay server ports, you use one and some re-sizers) It's fine if the screen is small in frame, or lower resolution (or defocused)

The other system that used to be used to get two video signals into one was I think CamPlex or VidiPlex(?) which sent one field of each source - so you got a 288 or 240 line feed of each source (the decoder field-doubled back to 576 or 480) with half motion.

Here the only standards used are 1920x1080 and 1280x720 and as it’s an NBC station it will be 1920x1080 (Fox and ABC are the only 720p only broadcasters). There used to be HD Lite on satellite where it was 1440x1080 and some cable companies in an effort to fit 100+ HD channels have downgraded the signals to 720p (but they cannot convert or manipulate broadcast channels on their system). The ATSC standard only supports those two for HD, but have been used for distribution. If there are multiple HD services the 1920x1080i may be downgraded to 1280x720p or SD widescreen, so those odd resolutions wouldn’t be transmittable.

Edit : However if they are using a DVE or resized for multiple boxes (not sure what it’s called when there are more than one video feed on air) it may not be noticeable.


Yep - it was Dish and/or DirecTV who use (or used) the lower horizontal resolution variants - as low as 1080x1080 I believe. People with modified receivers who could access the decrypted transport stream were able to analyse the video parameters ISTR. Things may have changed since then. AIUI the satellite platforms are allowed to re-encode the local broadcast channels they distribute - as they use h.264 rather than MPEG2 (which is still used OTA) for distribution these days ?

ATSC mandates (or kind of tried to) specific resolutions for OTA and cable - but the North American satellite operators can pretty much do what they like on their closed platforms.
NG
noggin Founding member

PromoSmart: Personalised trails on live BBC channels

Asa posted:
Having never had SkyQ I didn't realise there was no dedicated iPlayer app until today.

https://www.skygroup.sky/corporate/media-centre/articles/en-us/bbc-and-sky-agree-new-content-and-technology-partnership

The interesting bit for me though -
Quote:
The BBC and Sky are also in early stage exploration to use PromoSmart, powered by AdSmart Sky’s targeting technology, to serve up more personalised promotional content to BBC viewers. In practice, this will mean that viewers in different households could be shown different trailers for BBC content that are more relevant to their interests during the breaks between programmes when watching BBC channels live.



Is AdSmart frame accurate then? So it feels like genuinely part of the junction and not 'badly tacked on' and buffering? Maybe it can also offer idents we'd actually like to watch too Very Happy


It's been running for a good few years on Sky HD and Sky Q boxes on a number of channels. It's seamless - you literally have no idea it's happening when you are watching.

The adverts are already stored on the Sky+HD/Q boxes hard drive (so no buffering) and the broadcast stream is encoded in a manner that allows the h.264 stream to be spliced without any glitches (presumably ensuring GOPs don't get broken) There is DVB standard for triggering local advert insertion (and a way of carrying this in HD-SDI) but I don't know if Sky use that.

Sky distribute a library of commercials to all boxes for local insertion (I think they use DVB-S2 delivery - rather than IP - for the commercials, just using a spare tuner during downtime/overnight)

(The DVB standard is designed for local advert insertion at DVB-T/T2 transmitter sites or DVB-C cable head ends that are fed by satellite. It can also be used for triggering local news insertion I believe)
UKnews, London Lite and Richard gave kudos
NG
noggin Founding member

Half Frame Width HD Video Backhaul

A number of US platforms use lower resolutions than 1920x1080 for emission (i.e. the final leg to the viewer) - with 1440x1080 (as BBC HD used to use), 1280x1080 and 1080x1080 all used I believe - so the resolution loss caused by a 50% horizontal squeeze may not be that huge.

DVC Pro HD - which was a widespread codec in use for production (as it's supported by pretty much every platform - FCP, Avid, Prem Pro, Quantel/GVG - and operating system) uses 1440x1080 in 1080i25 and 1280x1080 in 1080i29.97 too (the lower frame rate of 50Hz systems means you get a bit more resolution)

I've worked on shows where video screens are fed by 1/4 screen crops and zooms of a single quad split graphic source (rather than tying up 4 replay server ports, you use one and some re-sizers) It's fine if the screen is small in frame, or lower resolution (or defocused)

The other system that used to be used to get two video signals into one was I think CamPlex or VidiPlex(?) which sent one field of each source - so you got a 288 or 240 line feed of each source (the decoder field-doubled back to 576 or 480) with half motion.
NG
noggin Founding member

ITV abandons the South Bank

dosxuk posted:
Would a production team tell the audience at a filming that they hate the facilities and will be moving out as soon as they can, even if it is what they are thinking?


No - and the production team members audiences usually get a chance to talk to are more likely to be junior people like runners, audience services and researchers rather than the Directors, Producers, Execs and Production Managers/Production Execs who make those decisions, and whose 'liking' of a facility can make a significant difference (sometimes talent also).