Harry

Abc1 Soon To Be Hd ?

339 posts in this topic

9 hours ago, davmel said:

Digging deeper they appear to still be using dual stream audio on many terrestrial HD channels with AC3 DD5.1 in addition to MPEG-1 layer 2 (like some of our Australian broadcasters did many years ago). But the UK also transmits their channels on Freeview SAT and they appear to have identical (mostly dual AC3/MPEG) audio streams as on terrestrial, see transponder 10847 V:

Certainly use dd5.1 and mpeg decoding [MPEG-2/MPEG-1 layer I & II ] in Iceland davmel ; a typical stb ;

http://tv.fo/content/DVB-T2-MPEG4-HD-2.pdf

Share this post


Link to post
Share on other sites

CWT,

You need to read more than the titie on the front. The specifications (at the back), are not DVB-T2 at all it is the same as our old STBs. It is a DVB-T box with HD and SD and no Dolby 5.1

Alanh

Share this post


Link to post
Share on other sites
41 minutes ago, alanh said:

CWT,

You need to read more than the titie on the front. The specifications (at the back), are not DVB-T2 at all it is the same as our old STBs. It is a DVB-T box with HD and SD and no Dolby 5.1

Alanh

what titie ? i dont see no tities

after making me scroll through a manual with lots of articles and no tities i found

MPEG-2 layer ii which supports up to 5 full range audio channels and an LFE-channel (Low Frequency Enhancement channel)

 

Edited by mello yello

Share this post


Link to post
Share on other sites

Mello yello,

You need to read more than the titie on the front page. The specifications (at the back), are not DVB-T2 at all it is the same as our old STBs. It is a DVB-T box with HD and SD and no Dolby 5.1

Video Decoding "MPEG-2 & MEPG-1 compatible" MPEG-1 has never been used for broadcasting vision. There is no MPEG-4 which is required by all broadcasters who transmit DVB-T2.

There is no mention of AC3 which provides the Dolby 5.1 signals. MPEG-2/MPEG-1 layer I & II is incapable of surround sound. If this STB was MPEG-4 capable, it also has to provide AAC sound compression which is also surround sound capable.

Alanh

Edited by alanh

Share this post


Link to post
Share on other sites
14 hours ago, alanh said:

CWT,

You need to read more than the titie on the front. The specifications (at the back), are not DVB-T2 at all it is the same as our old STBs. It is a DVB-T box with HD and SD and no Dolby 5.1

Alanh

Good to see you checked the specs carefully Alan ; even had a diagram showing the dolby ac3 5.1 sp/dif if you bothered to read the pdf :rolleyes:

btw was referencing what davmel said  

Quote

Digging deeper they appear to still be using dual stream audio on many terrestrial HD channels with AC3 DD5.1 in addition to MPEG-1 layer 2 (like some of our Australian broadcasters did many years ago).

didn't even mention mpeg4 ...

Quote

Rear Panel Description 
 
1 TERRESTRIAL IN Terr. input of the digital tuner. 2 LOOP OUT Terr. output for cascading to others devices. 3 VIDEO CVBS video output for TV AV in. 4 AUDIO HiFi output for stereo set. 5 COAXIAL S/PDIF Coaxial output for digital audio (AC3) 6 USB To connect with USB disk. 7 HDMI HDMI output for the connection to a TV set. 8 AC IN Mains input cable.


 
 

Share this post


Link to post
Share on other sites

So when are the ABC going to convert their studios to make HD programs?

They already have a distribution network which can transmit HD programs in MPEG-4 to all Australians. They are busilly upscaling their current SD programs of which there are many up to HD, but this does not improve image sharpness.

If they were to reequip their studios, then the transcoding would become unnecessary except for downscalling to the internet and mobile devices.

Then again if they were to be innovators and convert to DVB-T2 they could not only transmit more channels of HD but also to mobile devices from the same transmitters. There is millions of mobile phones in India which receive DVB-T2 from the broadcasters for free, and not the telco. Again this would make much of the transcoding irrelevant.

Alanh

Share this post


Link to post
Share on other sites

A bit more news from a very obliging Audience and Consumer Affairs lady in the ABC - no surprises here though - as there appears to be an increase in native HD programming over the past couple of weeks.  Some more bit rate on the HD channel would be nice though.

 

"Dear Sir,

 

Thank you for your email.  ABC Reception Advice have passed your email to Audience & Consumer Affairs for response.  Please accept my apologies for the delay in doing so.

 

It is correct that on Dec 7 we were only airing upconverted SD content until all our technical processes and requirements were completed (in mid Dec). In addition, not all of the content owned by the ABC is HD quality. When the ABC has HD quality programs, these are broadcast in full 1080i HD, which is higher resolution than the previous ABC News24 HD, which was 720p. The ABC is working towards increasing the number of programs it owns in HD, and expects to be fully native HD in the future.

 

Thank you again for taking the time to write.

 

Regards"

Share this post


Link to post
Share on other sites

ABC HD Sydney has ditched Dolby Digital audio (AC-3), which was only stereo, and replaced it with MPEG stereo @256kb/s.

So I guess that means any chance of providing some 5.1 AC-3 has bitten the dust.  It's 2017, and we're going backwards.

I'm amazed that pairing archaic MPEG stereo audio with h.264 HD video is even allowed in the DVB standard!

Share this post


Link to post
Share on other sites

Craig,

How many programs are they transmitting with surround sound content, not just the indicator showing? I suspect probably none. They are probably on the hunt for more spare data rate. They could have got surround sound using HE-AAC audio compression  https://www2.iis.fraunhofer.de/AAC/multichannel.html which is in the current Australian standard. It is backward compatible with stereo and mono and is part of the h.265 standards. Remember they are the last metro network to go HD 2nd time around.

Alanh

Share this post


Link to post
Share on other sites

The ABC are probably so desperate to save money that by moving to MPEG audio they don't have to pay royalties to Dolby or their license fee. Given that it's a MPEG-4 HD channel the audio should have been AAC rather than MPEG-1 because backwards compatibility isn't needed.

Oh, and Alanh, for bitrates of 128kbps and higher (whether stereo or surround sound 5.1+ channels) LC-AAC should be used. HE-AAC is preferred only for <128kbps streams.

Share this post


Link to post
Share on other sites

There is barely any HD content anyway, I remember when HD was a big thing all the stations began pumping out 1080 content everywhere and then it died down, quite a scam if you ask me when we have all these modern high definition TV's and cant watch anything nice on them unless we buy DVD Movies or pay for Foxtel.

Share this post


Link to post
Share on other sites

Whilst there is still a way to go, over the last couple of weeks, definitely more native HD content on the ABC. Some good viewing last night at, what to the naked eye, appeared a pretty reasonable bit rate (for FTA).  

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now