Picture twitches across cuts on 1080p freeview

[the-rence]

Is anybody else getting picture twitches across some cuts on BBC HD preview 1080p transmissions? My KDL-EX503 shows what looks like 2 or 3 frames of a slightly wider image before zooming back into normal size pictures on occasional picture cuts. 1080p blu ray images are fine.

[Bravia55HX]

the-rence,

Hi,

the thing you need to remember here is that freeview broadcasts are 1080i and not 1080p, transmissions in 1080p would be far too expensive to do so all transmissions are done 1080i,

so not really sure why you seem to be experiencing this phenomenon.

[KDL-CX520]

this problem is a synchronization problem for frame drawing between the broadcaster (BBC) and TV, if this happen rarely ignore it , you may also check other HD sources, if they are working fine.

In some cases the problem improved by setting the Color System to : PAL instead of AUTO...this is funny

Regards,

[the-rence]

Hi

BBC HD Preview are transmitting some programmes in 1080p (perhaps experimentally) at the moment - I'm sure this is the same (25) frame rate as their 1080i transmissions and therefore shouldn't require a larger bandwidth - or expense. As with blu-ray 1080p playback, my KDL-EX503 displays the 1080p icon when I switch to HD preview when it's transmitting progressive programmes.

[the-rence]

Changing the color system to pal instead of auto is not an available option on my screen. So no further at the moment.

[KDL-CX520]

Pls see your model i-manual here

http://support.sony-europe.com/tvhc/imanual/menus.aspx?site=odw_en_GB&m=KDL-32EX503&s=SM19

Scroll down , there is something written about video input settings depends on your region

Have a nice day

[Bravia55HX]

Hi,

personally i would stop twiddling around with the settings as its not relevant to the situation,

if as you say with blu ray its fine ( natuarally ), how about all the other channels?, my guess is they are fine too!, this business with BBC and their 1080P broadcast is still experimental so to be fair, messing up the settings on your tv for this one experimental channel is a bit of a mismatch is'nt it?.

i would wait and see how it is after christmas and see if the BBC settle on something definate.

[KDL-CX520]

i agree with Bravia55HX923, your TV is fine, because others HD sources playing well, BBC experimental Ch. lost the Synchronization sometimes.

i would explain that if one picture frame received by TV is corrupted so the TV will not understand the frame format and will try to draw the frame one time using PAL and one time with NTSC (in case the color system preset to AUTO), this is why you notice the picture twitches, By force the setting to PAL it will minimize the twitches but will not eliminate the problem totally .

I own a different model but you may try if the color systems are adjustable as per your manual.

[jokelly95]

We also get this - KDL-32ex503 and it's annoying on the BBC HD channel. The rest of the channels are okay. I have emailed sony and Sony blame the BBC because the picture is switching between 1080p and 1080i, This is correct as I have tested it by clicking on info when it happens and you can see the 1080i one minute and 1080p the other. The thing is I have watched a Samsung Freeview HD picture and the HD picture was totally stable the whole time. This implies to me that it's the tv that's at fault.

Sony - can we have a comment please?

[jokelly95]

This is interesting

http://www.bbc.co.uk/blogs/researchanddevelopment/2011/04/software-upgrade-for-bbc-hd-on.shtml

According to this:-

The Freeview HD platform has always been specified to provide a 1080p25  capability.  This is why STBs are mandated to have a 1080p50 output to  enable seamless up-conversion to a mode which is guaranteed to be  present in all display devices.  A great deal of material is shot  natively at 1080p25 and there are significant advantages in maintaining  1080p25 through to the viewer's display.  Within a single programme  interlaced may be used for moving credits, cross-fades and studio shots  whereas  progressive may be used for location shot material.

Also it goes on to say:-

The encoded bitstream can only  change at each GOP boundary to ensure  decoders maintain a consistent display. This means that each coded video  sequence either contains interlaced or progressive pic_struct values  within the bitstream.

That to me implies that the picture will always be changing from 1080i to 1080p and back. There is a fault on the sony decoder if it can't cope with this. Am I right in reading this this way? Is a fix being worked on?