TV Programmes Broadcast In AC3?

Forums › Freeview (DVB-T/DVB-S) › TV Programmes Broadcast In AC3?

1gkar

722 posts

Ultimate Geek

#21288 21-Apr-2008 22:50

Hi,

Are any FreeviewHD programmes being braodcast in AC3 at present? I ask because I haven't seen my Denon receiver switch across to Dolby Digital on any of the channels I have watched.
If so, are there any further requirements to receiving AC3 on Freeview? Cheers.

Silverstone LC14 HTPC Case/Intel E4600 CPU/GA-EP35-DS3 MOBO/Asus EN9500GT graphics/2GB RAM/total 2TB HDD space/HVR-2200 & 2X 150MCE tuner cards/LG GGC-H20L BD Drive/MCE2005/Mediaportal/TVServer 1.1.0Final/LG 55"3D LED-TV/Denon AVR-1803 receiver/X1 projector

sbiddle

30853 posts

Uber Geek
+1 received by user: 9996

Retired Mod

Trusted

Biddle Corp

Lifetime subscriber

#125472 22-Apr-2008 07:44

Underbelly appears to be the only show currently broadcasting a 5.1 audio stream.

1gkar

722 posts

Ultimate Geek

#125606 22-Apr-2008 17:07

Okay, so it's not my setup. Thanks for the confirmation.

lchiu7

6521 posts

Uber Geek
+1 received by user: 543

Trusted

#125625 22-Apr-2008 18:05

sbiddle: Underbelly appears to be the only show currently broadcasting a 5.1 audio stream.

Interesting. Most US shows TV3 shows in HD would have a DD5.1 track - wonder why they are not broadcasting that?

Staying in Wellington. Check out my AirBnB in the Wellington CBD. https://www.airbnb.co.nz/h/wellycbd PM me and mention GZ to get a 15% discount and no AirBnB charges.

richms

29098 posts

Uber Geek
+1 received by user: 10209

Trusted

Lifetime subscriber

#125698 22-Apr-2008 21:32

Probably have to deal with the 4% speed problem in their conversion to pal rates...

Richard rich.ms

old3eyes

9158 posts

Uber Geek
+1 received by user: 1364

Subscriber

#125762 23-Apr-2008 08:24

richms: Probably have to deal with the 4% speed problem in their conversion to pal rates...

There is no such thing a PAL in HD TV

Regards,

Old3eyes

lchiu7

6521 posts

Uber Geek
+1 received by user: 543

Trusted

#125792 23-Apr-2008 09:46

So if a source is 720p/60Hz and they broadcast 720p/50Hz what does that do to the picture?

My understanding is that HDTV's here can handle 720P/50 and 60Hz but US TV's which are much cheaper aren't really designed for 720p/50Hz and that poses problems for those who want to purchase BR discs designed for the European market

Staying in Wellington. Check out my AirBnB in the Wellington CBD. https://www.airbnb.co.nz/h/wellycbd PM me and mention GZ to get a 15% discount and no AirBnB charges.

Dyson

Shop now for Dyson appliances (affiliate link).

digitalepsilon

41 posts

Geek

#125849 23-Apr-2008 12:29

lchiu7: So if a source is 720p/60Hz and they broadcast 720p/50Hz what does that do to the picture?

My understanding is that HDTV's here can handle 720P/50 and 60Hz but US TV's which are much cheaper aren't really designed for 720p/50Hz and that poses problems for those who want to purchase BR discs designed for the European market

There is no 'PAL' as such but the 50 and 60Hz rates are part of standards used for HD transmissions. The standards needed to do that to make sure NTSC and PAL material shot in the past could be seamlessly shown in an HD world, so many of the problems associated with them (like speedup and audio pitch issues) haven't necessarily gone away.

If a NZ broadcaster has source that is 720p/60 they could downconvert it to its native 720p/24 (assuming it is TV show shot on film) and then run it at 25fps/50Hz. Most 720p HD releases on bittorrent are sourced from a 720p/60 broadcast downcoverted to 24p. Running at 25fps, you would need to re-encode the audio to match the faster framerate and the length of the feature would be reduced by 4%. Alternatively you can butcher video and throw away some of the frames to go direct from 720p/60 to 720p/50. The result would often be pretty jerky but it can be done and the original audio track would be left as is since the length of the feature won't change.

Researching though, the ATSC standard used in the USA has support for both 60 and 50Hz rates via the A/63 standard (see http://en.wikipedia.org/wiki/ATSC_Standards), however I don't know how many broadcasters choose to use that even when the originating material is 50Hz.

BR discs support the 24p format, and as far as I know most new film titles have been encoded in that format, matching exactly the timing of the original film. There should be no speedup or interlacing issues like there are with DVDs, at least with discs issued by major studios. Finally the 25fps speedup issues for PAL-based countries will be a thing of the past, at least with BR. If the receiver TV doesn't support a native 24p signal (I think only elite TVs currently do), it's up to the player to convert the 24p material into 1080i/30 or whatever to get a compatible signal.

Features shot on video and released direct on BR would probably choose to encode using the 50 or 60Hz modes so then perhaps there could be a region issue. That said, wikipedia and the ATSC standard suggests US TVs must support 50Hz input...

Anyways this is a bit OT so I'll end it there.

On topic, whether any of this has anything to do with why so few programmes are in AC3, I'm not sure since it depends on how the conversion from 60Hz to 50Hz is done and whether that's done here in NZ or is simply done by the US source before it's provided to an international broadcaster.

openmedia

3449 posts

Uber Geek
+1 received by user: 878

Trusted

#125871 23-Apr-2008 13:15

Well based on the information in the MHEG-5 DTT EPG the following shows should have Dolby

CSI: New York
Boston Legal

Also according to the MHEG EPG Numb3rs is replacing Underbelly on Sunday.

Generally known online as OpenMedia, now working for Red Hat APAC as a Technology Evangelist and Portfolio Architect. Still playing with MythTV and digital media on the side.

mentalinc

3384 posts

Uber Geek
+1 received by user: 1023

Trusted

#125878 23-Apr-2008 13:35

openmedia: Also according to the MHEG EPG Numb3rs is replacing Underbelly on Sunday.

Underbelly has been dropped due to poor ratings will return later in the year at a differnt time slot - Think it is stated in the current Time out from NZ Herald

CPU: AMD 5900x | RAM: GSKILL Trident Z Neo RGB F4-3600C16D-32GTZNC-32-GB | MB: Asus X570-E | GFX: EVGA FTW3 Ultra RTX 3080Ti| Monitor: LG 27GL850-B 2560x1440

Quic: https://account.quic.nz/refer/473833 R473833EQKIBX

sbiddle

30853 posts

Uber Geek
+1 received by user: 9996

Retired Mod

Trusted

Biddle Corp

Lifetime subscriber

#125885 23-Apr-2008 13:52

Underbelly is staying on Sunday nights after the about face by TV3.

TV3 website says it's on this Sunday..

openmedia

3449 posts

Uber Geek
+1 received by user: 878

Trusted

#125943 23-Apr-2008 18:43

Ok the EPG updated with Underbelly back on, plus I missed a couple of shows off the list. The following are currently flagged for both HD and Dolby in the DTT EPG.

CSI: New York
Boston Legal
Underbelly
Bones
Dexter

Generally known online as OpenMedia, now working for Red Hat APAC as a Technology Evangelist and Portfolio Architect. Still playing with MythTV and digital media on the side.

Dyson

Shop now for Dyson appliances (affiliate link).

sbiddle

30853 posts

Uber Geek
+1 received by user: 9996

Retired Mod

Trusted

Biddle Corp

Lifetime subscriber

#125955 23-Apr-2008 19:36

How do the Zinwell's handle AC3 broadcasts? Do you automatically get an AC3 signal from the SPDIF connector during a show as well as the analogue output or do you have to select the audio type?

richms

29098 posts

Uber Geek
+1 received by user: 10209

Trusted

Lifetime subscriber

#125967 23-Apr-2008 20:32

old3eyes:
richms: Probably have to deal with the 4% speed problem in their conversion to pal rates...

There is no such thing a PAL in HD TV

I said pal rates, not pal.

I have being advised that all DTV in NZ has to be at 50Hz so that the boxes can do output at 50Hz - Why, who knows, but I have seen cheap as anything sat STBs that will output PAL when given NTSC so I cant see why HD boxes cant do the same when outputting to a SDTV.

Dont really notice teh difference on voices, but with theme music etc its quite apparant, quite annoying. Plus it means they get to fit another add or 2 in without editing. I had hoped that HD and DTV would spell the end of this whole systems conversion crap, sadly not.

Richard rich.ms

digitalepsilon

41 posts

Geek

#125985 23-Apr-2008 21:41

I had hoped that HD and DTV would spell the end of this whole systems conversion crap, sadly not.

My feelings exactly. In their efforts to ensure backward compatibility, they seem to have also ensured the new generation of hardware follows the same divided 50/60Hz spec as the old stuff, albeit with a larger picture. It is the most practical and economical solution though.