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Old 06-08-2009, 15:21
d'@ve
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Luxe HD always looks pretty good, and it works at 10Mb/s.
Luxe SD 2.9 mbps

Luxe HD 5.5 mbps (with 128kbps audio).

The reason it looks OK is because it uses undemanding material (brightly lit scenes, talking heads, little or no action). When they occasionally do slow pans, the resolution and clarity really drop away.

It would be a disaster if the major HD channels went there... new encoders or not.
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Old 06-08-2009, 16:16
JordanDS
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I now get jitter on static-ish scenes, e.g. David Mitchell talking on Who Do You Think You Are? when that never happened previously. It also happens sometimes with cross-fades. This is with a Sony BDP-S350 Blu-ray player playing back a recording authored to DVD as AVCHD format.

Those frames seem to jump back and forth a bit. Shots with more continuous movement are perfect.
It couldn't cope with slow transitions between some black-and-white etchings and back to live action about 45 minutes into last night's Who Do You Think You Are?

Before I'd read that new encoders were in use, I was sure I was seeing motion artifacts and some 'blocky' transistions on Dragon's Den which I hadn't noticed the week before.
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Old 06-08-2009, 21:00
scoobiesnacks
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I've posted this comment to the BBC POV board.

Yesterday BBC HD slashed the bandwidth of its transmission by 40% and this has a direct impact on picture quality we are getting. BBC HD is now a poor relative of its former self and cannot compete with Sky HD , Channel 4 HD or ITV HD.

You can see the cutback here:
Linowsat Bitrates - DVB PID-Lists and VDR channels.conf

What's the impact you might ask? The result is a picture quality at times like the early days of digital TV when you get blockiness (so called digital artefacts) because there is insufficient bitrate. Although still scenes BBC HD can cope with , complex scenes with smoke or movement are badly affected because they require more bandwidth than the signal can be compressed into.

This is the second time the channel has cut its picture quality. 2 years ago BBC HD transmitted at 20mbps. Today Eurosport HD transmits at that rate using the latest encoder. BBC HD however has cut its bitrate to 9mbps. So don't believe the marketing hype - BBC HD is not true HD - its a cheaper, poorer alternative.

I call upon the BBC HD channel to restore the picture bandwdith to at least 16mbps - what it was last week. Not 9mbps

Note the graph with the size of the cutback
http://www.linowsat.de/0282/bitrate/2050/6940.html


Everyone if you have time please chip into the debate on BBC Points of View
http://www.bbc.co.uk/dna/mbpointsofv...thread=6819732
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Old 06-08-2009, 21:14
u006852
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I've posted this comment to the BBC POV board.




Note the graph with the size of the cutback
http://www.linowsat.de/0282/bitrate/2050/6940.html


Everyone if you have time please chip into the debate on BBC Points of View
http://www.bbc.co.uk/dna/mbpointsofv...thread=6819732
I have only watched Rick Stein this evening but actually thought it looked very good.

I know you seem to want some sort of campaign, but dare I suggest that an objective assessment is made of the effects of this change. I have highlighted problems that I have perceived, but also acknlowledged where there are no problems.

Don't just turn around and say "it has all turned to s***" because it simply has not.

If there are more services to come they could be stat muxed which will improve things. You have to question why the drop has been implemented. Unfortunately I am sure you won't get an official answer.

Just so long as the freed up space is not used for SD channels, if it is then even I will throw my toys out the cot.
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Old 06-08-2009, 21:19
scoobiesnacks
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I have only watched Rick Stein this evening but actually thought it looked very good.
I agree at times it was ok, close cooking shots for instance. Anything with movement in it though showed shortcomings. His shirt had blocky artefacts on it when I checked.
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Old 06-08-2009, 21:22
Andy Quested
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Dear scoobiesnacks

I will get your post in due course from the POV site but there is a BBC HD Picture Quality blog too for comments.

You only site bit rate as your measure of quality whereas there are many factors that have an impact on compressed moving images.

Andy
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Old 06-08-2009, 21:26
u006852
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I agree at times it was ok, close cooking shots for instance. Anything with movement in it though showed shortcomings. His shirt had blocky artefacts on it when I checked.
I did not actually notice this. Unfortunately I did not record the program so cannot check again.
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Old 06-08-2009, 21:36
scoobiesnacks
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Dear scoobiesnacks

I will get your post in due course from the POV site but there is a BBC HD Picture Quality blog too for comments.

You only site bit rate as your measure of quality whereas there are many factors that have an impact on compressed moving images.

Andy
Andy - I rate my measure of quality purely by what I see - and right now its artefacts when I actually should be seeing wood grain, in still background scenes in "Spanish Flu".. from a normal viewing distance, on a plasma tv.

The picture quality is average at best in my honest opinion. What I don't understand is you now have the equipment presumably to have the best picture out there. Why have you decided to go for second best?
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Old 06-08-2009, 21:50
Wayne Moule
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I would guess the BBC are standardizing their HD output for the launch of Freeview HD on the limited space that DTT has.

ITV HD is a similar bitrate.

Rick Stein looked excellent to me tonight.
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Old 06-08-2009, 21:50
u006852
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My initial impressions are that any source material that has noise (camera or whatever) are really making the encoder struggle.

Just gone to a well lit scene in Spanish flu from a poorly lit and noisy one and the issues I see disapear.
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Old 06-08-2009, 21:53
technologist
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Andy - I rate my measure of quality purely by what I see - and right now its artefacts when I actually should be seeing wood grain, in still background scenes in "Spanish Flu".. from a normal viewing distance, on a plasma tv.

The picture quality is average at best in my honest opinion. What I don't understand is you now have the equipment presumably to have the best picture out there. Why have you decided to go for second best?
Andy has made reference in his Blog to the effect of Noise on the coding ... and some shots of the office have this -
but the detail is out of focus ...
And may be ( I would need side by side comparison) this coder is different to the other one on this ... generally all be it on a very good Lcd I do not see gross artefacts.
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Old 06-08-2009, 22:01
scoobiesnacks
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I would guess the BBC are standardizing their HD output for the launch of Freeview HD on the limited space that DTT has.

ITV HD is a similar bitrate.

Rick Stein looked excellent to me tonight.
Cooking shows are always the best. though I maintain a saw artefacts on his shirt of all things. Agree with you though at times it looked fine.

This weekend will be the proof. Football on 10mbps. It will be like playing spot the ball versus the digital artefacts.

Unless we get a sudden change of heart on the bitrate of course? Anyone....?
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Old 06-08-2009, 22:04
Wayne Moule
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Cooking shows are always the best. though I maintain a saw artefacts on his shirt of all things. Agree with you though at times it looked fine.

This weekend will be the proof. Football on 10mbps. It will be like playing spot the ball versus the digital artefacts.

Unless we get a sudden change of heart on the bitrate of course? Anyone....?
Footy on Sky Sports SD looks very fine @ < 10mbps , so I think it will look excellent on BBC HD.

I think 10mbps will be the norm for broadcast HD I'm afraid, due to bandwidth space.
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Old 06-08-2009, 22:15
Snoods
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Hmmm well it's all right for some.

This is how BBC HD now looks in DVB Viewer in Windows 7 with the native Microsoft Video Decoder.

All was well before the encoder change. Any ideas why DVB Viewer is now baulking at BBC HD ?

Haven't tried any fixes yet been too busy. Anyone else having problems now in Windows 7 with BBC HD or is it just me ?

BBC HD (DVB Viewer)

http://www.flickr.com/photos/freesat...29048/sizes/o/

Luxe HD and ITV HD are fine as usual.


The grab was from this afternoons preview, but tonights programmes are just the same.
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Old 06-08-2009, 22:20
derek500
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That's awful. What band is it, New Kids on the Blocking?
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Old 06-08-2009, 22:20
u006852
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I'm sure this isn't my imagination, but I see flickering from time to time. Seems to happen randomly, no obvious reason.
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Old 06-08-2009, 22:23
Snoods
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That's awful. What band is it, New Kids on the Blocking?
Yes i think so Derek, it's totally unwatchable now. (for me)

I will have to dig out the Cyberlink codec and give it a go to see if anything changes.

I'm quite mystified as to why DVB Viewer can no longer cope with it. There must be a drastic change somewhere to cause that amount of constant blocking.


I wonder if its DD 5.1 related. Tom Jones is on at the moment and piccy is fine no blocking at all. (Not DD 5.1)

Will have to look and see if the blocking returns during 5.1 audio.

(Michael Palin at midnight is DD5.1 so will lookie then)

Well the blocking is back, so bang goes the DD 5.1 theory.
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Old 06-08-2009, 23:00
Wayne Moule
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The BBC did say there was a sound issue with the old codec, now fixed in the new one.
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Old 06-08-2009, 23:03
Snoods
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The BBC did say there was a sound issue with the old codec, now fixed in the new one.
Well the sound is fine, but they broke the piccy in my DVB Viewer.

Fling that new fangled encoder out the window, it's useless.
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Old 06-08-2009, 23:27
mwardy
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Well the sound is fine, but they broke the piccy in my DVB Viewer.

Fling that new fangled encoder out the window, it's useless.
Is this any help?

http://www.dvbviewer.info/forum/inde...howtopic=18449

They have been using wrong AC3 PES start codes for months, but Andy Quested said they would correct this with the next upgrade. Perhaps they have (can't test it atm).

I don't have DVBViewer so this is a bit of a shot in the dark.
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Old 06-08-2009, 23:30
Jarrak
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Well the sound is fine, but they broke the piccy in my DVB Viewer.




I had problems with it as well, tried the latest version of CoreAVC and it cleared it up.
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Old 07-08-2009, 00:11
remlap
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No problems for me with Cyberlinks H.264/AVC codec that came bundled with this system.

DXVA fine to graphics card its doing its job
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Old 07-08-2009, 01:23
White-Knight
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"ITV HD is a similar bitrate"

Cooking shows are always the best. though I maintain a saw artefacts on his shirt of all things. Agree with you though at times it looked fine.

This weekend will be the proof. Football on 10mbps. It will be like playing spot the ball versus the digital artefacts.

Unless we get a sudden change of heart on the bitrate of course? Anyone....?
Football on ITV 1 can be terrible at times. HD looks great until the camera moves slightly then the whole pitch just becomes a blur. Maybe I shouldn't be counting blades of grass but isn't that what HD was always about and advertised? In sports see every blade of grass?

As for BBC HD, I've not watched enough of it to make a comment other than to say that Wildest Dreams (yesterday) was excellent - in fact the best I've seen that particular programme look.

Maybe the BBC just have some fine tuning to do.

Also, no-one has actually said they've bought Ateme encoders. All we know is the bit rate has been reduced. that could just be the result of better software for their existing encoders so you can't just assume they have LUXE quality encoding now.
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Old 07-08-2009, 01:28
scoobiesnacks
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Also, no-one has actually said they've bought Ateme encoders. All we know is the bit rate has been reduced. that could just be the result of better software for their existing encoders so you can't just assume they have LUXE quality encoding now.

They have confirmed new encoders but not named the model- Andy Quested has confirmed here and on BBC HD Blog. They went live at 2am Weds I think.

Thats what I thought incidently - I never though they would buy new encoders and cut bandwidth at the same time. Though come to think of it they have warned previously they want to continue to cut bandwidth.
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Old 07-08-2009, 02:39
d'@ve
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Hmmm well it's all right for some.

This is how BBC HD now looks in DVB Viewer in Windows 7 with the native Microsoft Video Decoder.

All was well before the encoder change. Any ideas why DVB Viewer is now baulking at BBC HD ?

Haven't tried any fixes yet been too busy. Anyone else having problems now in Windows 7 with BBC HD or is it just me ?

BBC HD (DVB Viewer)

http://www.flickr.com/photos/freesat...29048/sizes/o/

Luxe HD and ITV HD are fine as usual.


The grab was from this afternoons preview, but tonights programmes are just the same.
It's been fine in DVBViewer in Windows XP.

Incidentally, I noticed during The Bill on ITV HD on Thursday that their bitrate is approx. 10.6 Mbps... over 10% higher than the new BBC HD bitrate. There were no issues that I noticed, on ITV HD.

What I don't know is if the new BBC encoder/codecs etc. are 10% more efficient than the ITV ones.
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