BBC/ITV/ Ch4 / Ch5 HiDef Freeview Trial

Seft · 1 Jun 2006 at 13:44

Realtime PC decoding should be possible with the introduction of CoreAVC 1.1 on the seventh of June (timing deliberate

)

@Energize: The BBC streams are using MBAFF interlacing, which is much more intensive than your normal h.264 stream.

Also, h.264 != DivX, XviD (different part of the MPEG4 spec). You must have the quality very low if you are encoding at 24fps

Lanz · 1 Jun 2006 at 13:57

Seft said:
Realtime PC decoding should be possible with the introduction of CoreAVC 1.1 on the seventh of June (timing deliberate )

@Energize: The BBC streams are using MBAFF interlacing, which is much more intensive than your normal h.264 stream.

Also, h.264 != DivX, XviD (different part of the MPEG4 spec). You must have the quality very low if you are encoding at 24fps

What app do you use to view streams? I think i need a kosha version of tsreader maybe.

Energize · 1 Jun 2006 at 18:55

Seft said:
Realtime PC decoding should be possible with the introduction of CoreAVC 1.1 on the seventh of June (timing deliberate )

@Energize: The BBC streams are using MBAFF interlacing, which is much more intensive than your normal h.264 stream.

Also, h.264 != DivX, XviD (different part of the MPEG4 spec). You must have the quality very low if you are encoding at 24fps

The interlacing isnt going to change 40% cpu usage to 100%, since h.264 is better than xvid you dont need the quality settings as high anyway.

Seft · 1 Jun 2006 at 19:01

Energize said:
The interlacing isnt going to change 40% cpu usage to 100%.

The rest of the world disagrees with you. I won't post a link to a sample as I'm not sure it's allowed here, but if you get it working at full fps, you should really tell everyone what you're doing.

Energize · 1 Jun 2006 at 19:03

Seft said:
The rest of the world disagrees with you. I won't post a link to a sample as I'm not sure it's allowed here, but if you get it working at full fps, you should really tell everyone what you're doing.

The rest of the world? Lol, its a trial run of a service which is in the Uk only, and very few people have access to. Most people in the world dont have computers.

Seft · 1 Jun 2006 at 19:17

Energize said:
The rest of the world? Lol, its a trial run of a service which is in the Uk only, and very few people have access to. Most people in the world dont have computers.

Fine, my experience included, everyone who has tried playing it (including those who tried playing captured material), was unable to achieve full fps on high-motion scenes.

EDIT: I just got powerDVD (which has GPU acceleration). I can decode on x2 3800 + 2.4, 7800GT at full FPS with ~80% load

FrankJH · 1 Jun 2006 at 20:38

anyway everyone get off this thread (-: unless yur actually interested in the official equipment hahahahaaha

FrankJH · 3 Jun 2006 at 17:50

Picked up the STB today (from Ch4 offices in SW1), which is an i-can 3800T box , which looks much like any STB from the front with a top-up TV slot also.

Roun the back it has power, two scart connectors, analogue L+R, RF in and out, HDMI, SPDIF, ethernet and USB 2.0

For anyone who is interested; STi7100 CPU, 68Mb Flash memory and 192Mb RAM

1280*720 & 1920*1080 available res (and SD upto 720*576)

At the moment I can only pick up one BBC HD channel which is just showing clips, as soon as I catch a full HiDef broadcast I will try and take pics from SD BBC and HD channel for comparison (if anyone wants to see) - of course its also picked up the standard 50 odd channels or so from freeview.

I currently have the res set to 1080i even though I am only using a Samsung 32R41BDX , it just seems a little better than 720p, but I may change this once the BBC have finalised the transmission rate ( we were advised they willl be changing this up until thebeginning of the World Cup)

/edit ..... I have just checked the BBC HD website and there doesnt seem to be much on at all before the WC - I was hoping there would be some wildlife programmes or simulcasts to do some comparison but it seems not - they have a couple of programs but these have not been filmed in HD , so no live pics for a while I am afraid)

Goatboy · 3 Jun 2006 at 18:24

I think it's just the same channel that's on sky and telewest where nearly everyting is upscaled, if you go through the listings far enough there are a few nature programmes that are HD.

Tesla · 3 Jun 2006 at 20:31

It's odd that 1080i looks better than 720p considering 720p is the panels native res.

Ben · 3 Jun 2006 at 20:42

Energize said:
The interlacing isnt going to change 40% cpu usage to 100%, since h.264 is better than xvid you dont need the quality settings as high anyway.

Think someone needs to read up a bit more on h264/MPEG4-AVC.

FrankJH, sounds great. Quality wise 1080i should look slightly better even when downscaled compared to 720p, however 720p should have smoother motion, depends on preference really.

FrankJH · 3 Jun 2006 at 21:38

I am sure you are right - the demo stuff was all music programs and slow moving wildlife - which looked good but difficult to really compare as soon as the WC starts I will be flicking between them to see which is better.

tesla - as above , however remember that the panel is actually slightly better than 720p ( native is 1366*768 instead of 1280*720) so using the tv's downscaling may still end up better as I would guess the image should be slightly better - but as Ben said fast motion might change this once I get a chance to view.

Goatboy, you may well be right however the bbc website was only willing to tell me the timetable upto about Wednesday of this coming week, and it was either SD upscaling for about an hour a night or the rolling demo.

Once proper HD is shown I will happily try and produce some pics for people to get a proper idea. I was also hoping that ITV would be broadcasting their matches in HD (and Ch4 would be doing something also) but as yet their channel isnt broadcasting - or the tuner isnt picking it up - as this is a trial what do people think about the possibility of all terrestrial channels broadcasting on the same trial channel ( as there isnt enough broadcasting space for them all to do it until analogue gets turned off)?

It was just curious that the BBC is the big pusher of this, and yet I picked it up from CH4 offices and in the included leaflets it clearly states BBC and other broadcasters........... will update either way as soon as I know more

MrM3 · 3 Jun 2006 at 22:01

Damn I signed up for this... twice I think.

I have Sky HD but would hav preferred yours for ITV World Cup coverage.

Do you keep the stb afterwards? Can it record?

Energize · 3 Jun 2006 at 22:54

Ben said:
Think someone needs to read up a bit more on h264/MPEG4-AVC.

Well it's not me because I encode with it all the time.

Seft · 3 Jun 2006 at 23:51

Energize said:
Well it's not me because I encode with it all the time.

More specifically, the difference betwwen PFAFF and MBAFF.

FrankJH · 4 Jun 2006 at 00:48

MrM3 said:
Damn I signed up for this... twice I think.

I have Sky HD but would hav preferred yours for ITV World Cup coverage.

Do you keep the stb afterwards? Can it record?

Well they where giving away the stb to people just walking in today - so I dont know why you didnt get the email saying you could be part of the trial.

As long as you complete all the online questionaires ( once a month I believe) and do a few phone questionaries for the 6 months til Xmas, you are entitled to keep it yes ( i think there are other incentives also but cant remember the details)

No it cant record - I am going to see if my dvd/hdd recorder can do it justice when there is real programing to be recorded.

If anyone has HD ITV it will be sky so I wouldnt worry too much. I am hopeful I get it also but I am not certian

Energize · 4 Jun 2006 at 01:09

Seft said:
More specifically, the difference betwwen PFAFF and MBAFF.

I know the differences the problem with some people is because of poor codecs currently avalible to decode the stream not solely because of the interlacing normally needing tons of power.

FrankJH · 4 Jun 2006 at 02:01

Without being rude - it would be nice to keep this for the official equipment, I know a number of people from here have signed up

If you want to talk codecs etc etc then by all means create a new thread........... just remember that as far as I am aware the BBC is only transmitting the triial from Crystal Palace, so if you dont have your tv signal coming from there you wont get the new HD channel anyway.

Energize · 4 Jun 2006 at 02:16

FrankJH said:
Without being rude - it would be nice to keep this for the official equipment, I know a number of people from here have signed up

If you want to talk codecs etc etc then by all means create a new thread........... just remember that as far as I am aware the BBC is only transmitting the triial from Crystal Palace, so if you dont have your tv signal coming from there you wont get the new HD channel anyway.

Ill stop talking about codecs but realisticaly, there isn't likely going to be anyone else here who has the offical equipment and is going to discuss it.

FrankJH · 4 Jun 2006 at 07:05

Well actually there was a thread not so long ago with loads saying they had signed up- but as to whether they got the box, I have no idea

BBC/ITV/ Ch4 / Ch5 HiDef Freeview Trial

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