Digital TV Technical Discussion

A bit late, but these small black bars come from 720x576 not being exactly 16:9 (or 4:3) according to some interpretation of SD digital video standards.
When following this interpretation, the active picture area not 702 pixels wide with 8-9 pixels of “not active picture area” to round out the 720px. I presume the extra sampling was for blanking or some such reason.

When SD video was still king, some people created content a few extra pixels wide to accommodate the extra space, but now that SD is almost universally down-scaled from HD, you get black bars if equipment used follows this interpretation.

The Adobe suite was notorious for following the 702 not 720 interpretation.

Considering most equipment (particularly digital consumer TVs) just ignore this whole thing, so the de-facto standard is 720x576 = 16:9 (or 4:3) these days and you get weird black bars on almost every device.

For the curious: I’ve dug these two links out of my browser’s bookmark hell
One from a graphics artist from around the time and the link from BBC Commissioning he quotes in the blog post

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Awesome article. Explains a lot of issues I had rendering videos in Sony Vegas back in the day.

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Shouldn’t it be 704x576, not 702x576? I’ve never seen a 702 option on an encoder.

It’s possible to set the SAR or PAR on the stream to make the final result come out as proper 16:9 without black bars on SD, regardless of 720 or 704. For some reason though, the default aspect ratio usually ends up as 16:11 in SD, which would explain the black bars.

You’re still not quite getting it.

For example, Seven still want to sell specific ads for regional/local advertisers on the regional services.

It’s a bit hard to do that in these overlapping areas if viewers can’t easily find the regional Seven services on their TV and are instead watching the metro version.

There’s still value for networks and advertisers in making sure viewers are watching their local service and not an out-of-area channel.

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Here’s an interesting question. In such overlapping markets (e.g. the Gold Coast) how many people watch the capital city station and how many watch the regional affiliate?

Currently OzTAM conducts ratings for the capital city areas while RegionalTAM conducts ratings for much of the regional areas, but does anyone provide an overall picture of ratings in overlapping markets?

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I think it has been discussed before and to be honest, I doubt that the Northern NSW regionals are being watched on the Gold Coast. The double up of stations is a waste of bandwidth.

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Bandwidth has nothing to do with it. They’re all on different frequencies

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Forgive my lack of knowledge, but is there actual effort by the NNSW broadcasters to penetrate the Queensland side of the Gold Coast market, or is it just a convenient outcome of having strong transmitters on the NSW side?

NBN has a full local news service with inserts while WIN has local updates. Seven Regional doesn’t have anything however.

Ok, then what about SBS in overlap areas where both metro and regional signals are received? In some states there is a difference in the commercial content with the SBS signal splitting 12 ways. As such, SBS seems to still run ok with its single set of ‘3’ LCNs in areas with overlap.

Is time the LCNs mirror the on-screen branding.

Yes, for the transmitters serving the Gold Coast, the northern NSW regional broadcasters do things especially for the Gold Coast that they don’t do for the rest of their market, including:

  • Timeshifting their programs to eastern standard time when NSW has daylight saving time
    • this is so that age related programming isn’t shown at the wrong time
  • Having Brisbane-based news bulletins rather than Sydney-based
  • Where applicable, carrying Queensland state sporting shows rather than NSW state-based ones.

Also, their market is divided into regions and each region has different advertising. The Gold Coast is one such region.

It hasn’t been about strong transmitters (or good antennas) since the mid 80’s. The Gold Coast has its own transmitters serving different parts of the Gold Coast, and each transmitter site has both the capital city and reginal stations as well as ABC & SBS.

IIRC Seven Regional carries Seven News Sydney (4pm + 6pm) and NBN carries Nine’s Afternoon News Sydney (they have NBN News at 6) Only WIN carries 10 News First Queensland.

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I did read/hear somewhere that the ratio is about 85/15 in favour of metros.

The reality is a bit less… it’s usually 1 local Gold Coast report per night sourced from Nine and the rest of the Gold Coast news window is news from the Northern Rivers and further south.

All of these variations pretty much render the duplication of regional and metro services pointless.

When the digital switchover occurred the Gold Coast and Central Coast should have been separated from the Brisbane/Lismore and Sydney/Newcastle licence areas respectively and had their own licence areas created (they’re certainly big enough to justify it).

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T’was a joke. A poor attempt but a joke nonetheless.

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Easier said than done back then. 6 commercial licenses owned by 6 different companies - who then gets the 3 licenses that make up the new license area? Or a joint venture?

That said, it’s slightly easier now with Seven and Nine owning the old Prime and NBN licenses now and thus owning 2 licenses each. Ten and WIN is still seperate though.

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The regionals arent doing this one out of the goodness of their hearts - it’s mandatory

Am I right in saying that NRTV is licensed for the Central Coast, but doesn’t have a transmitter there? Thus it would be quite easy to have one set of commercial stations as each of the other two regional affiliates is owned by its respective capital city station.

There are 3 transmitter sites on the Central Coast, NRTV/WIN is only on air at the northern most one (Forresters Beach/Wyong) and is the Newcastle feed (no localised Central Coast ads).

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Thanks. @Radiohead

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