G7503 (Zinwell) picture glitching on HD

Forums › Freeview (DVB-T/DVB-S) › G7503 (Zinwell) picture glitching on HD

sjadd

61 posts

Master Geek

#25238 15-Aug-2008 23:44

I've been watching some of the Olympics in HD with a G7503-DSE and have been noticing picture glitches in some of the sports, where the picture will freeze for about 1-2 seconds before continuing (audio is unaffected).

The weird thing is that it doesn't seem to be completely random, basically it only happens in fast moving sports that have a lot of camera angle changes. I was just watching some track cycling just before and it happened quite a lot, and always just before the picture was about to change from focusing on a close-up of 1 rider to a wider shot.

I also have a PC with a HVR2200, and it's perfectly fine so I guess I'll be getting the G7503 replaced. Before I do I thought I'd see if anyone had heard about this problem (mainly so I can tell DSE that it's a known issue

). Also I would be interested generally if anyone knows what may be going on here, as it's definitely not a random thing (and has never happened on a non-HD signal).

Cheers.

sbiddle

30853 posts

Uber Geek
+1 received by user: 9996

Retired Mod

Trusted

Biddle Corp

Lifetime subscriber

#157347 16-Aug-2008 07:01

If you're not getting the same results on the PC then chances are it could be the STB - the quality of the Zinwell boxes in general is only pretty average.

As for picture breakup there has been a lot in outside events (particularly the cycling) where the microwave uplink has been lost between the ground and presumably the helicopter above that's relaying the picture.

scottjpalmer

6032 posts

Uber Geek
+1 received by user: 790

Moderator

ID Verified

Trusted

Lifetime subscriber

#157352 16-Aug-2008 09:08

I've noticed it too on many different sports, and yes before/as the shot changes.

tristanb

89 posts

Master Geek

ID Verified

#157471 16-Aug-2008 22:58

I've also noticed these freezes with our G7503. They tend to happen before a scene/shot change - which I guess is because a whole new keyframe (and a lot of data) is needed. I'm not sure if its exacerbated by poor reception, or just a function of the extra processing it takes for a new scene to be displayed.

I've only seen it on the Olympics, and initially I thought it might be NZ's or Olympic signal rather than just mine. But it does sound like a set-top box problem if your other one is fine.

mcraenz

1140 posts

Uber Geek
+1 received by user: 222

#157493 17-Aug-2008 11:09

HVR2200, I've noticed it too, but ONLY on camera change I guess it's at their end.

Help me build a better way of doing politics in Aotearoa New Zealand

political.nz

amphibem

138 posts

Master Geek

#157507 17-Aug-2008 12:39

I've had freezing and blocking with a Nova T 500 and Mediaportal, although I supect some of it is my box. It does seem to mostly be a feed issue, as said before particularily with the moving (and hence wireless) cameras.
The tech to wirelessly transmit HD must be pretty new, and it is a large data stream to deal with.

Desktop: 5200 X2 - 3GB - 320GB - Nvidia 8600GT - Vista Home Premium - PVR150 - MediaPortal 1.0
My HTPC Blog - HTPCnz, the Home Theatre PC Resource

mcraenz

1140 posts

Uber Geek
+1 received by user: 222

#157549 17-Aug-2008 18:18

I'm not talking about blocking or corruption, just a freeze for a second as the camera changes, I really saw this on the out cycling races.

Help me build a better way of doing politics in Aotearoa New Zealand

political.nz

Quic Broadband

Move to New Zealand's best fibre broadband service (affiliate link). Free setup code: R587125ERQ6VE. Note that to use Quic Broadband you must be comfortable with configuring your own router.

linw

2893 posts

Uber Geek
+1 received by user: 1205

#157601 17-Aug-2008 22:09

I have had these mini freezes on the DSE Freeview box and the SKY box. As others have said, it seems to happen on camera changes. Don't really think we can use these as an argument to take the box back!

sjadd

61 posts

Master Geek

#157606 17-Aug-2008 22:28

Oh well at least it's a common problem, I guess that's kind of good from a selfish perspective. I have a knack of getting imperfect equipment (e.g. I have never owned an LCD display without a dead pixel!) so I didn't want to sell myself short on this one. Won't bother trying to replace it then.

whatty

42 posts

Geek

#157682 18-Aug-2008 11:49

Host Broadcaster End nothing to do with Freeview or the zinwell box. Low shot (side) on rowing and Track cycling side camera are especially bad.

HD wirless links I susspect....

yellow15

134 posts

Master Geek
+1 received by user: 6

#157765 18-Aug-2008 16:15

linw: I have had these mini freezes on the DSE Freeview box and the SKY box. As others have said, it seems to happen on camera changes. Don't really think we can use these as an argument to take the box back!

I believe it's actually the other way round... when the operator at either TVNZ or Beijing notices there is a freeze on the image (probbably casued by the interupt in signal transmission), he just immediately swtich the camera to another one.

i notice this "glitching" problem on HD freeview, Satelite Freeview and analogue TV one broadcast. it happens most often during outdoor events

samj

8 posts

Wannabe Geek

#157781 18-Aug-2008 17:00

I'm seeing this too on my Zinwell (DSE) box. At first I just assumed it was some issue with the feed coming into TVNZ from Bejing but then I looked closely at the picture when it froze: the MPEG artifacts around the TV One logo like the mosquito noise and blockyness were still there in the freezed frame.

Presumably if this was an issue with the feed these artifacts wouldn't be there when the picture was paused (since it would essentially be a still picture to the encoder -> high encoding quality). Maybe it is something going on in the Zinwell box? Or are TVNZ just using crude methods to switch between shots (perhaps due to them not being fully equipped for HD broadcasting yet) which cause the decoder to slip up?

Lenovo

Shop now for Lenovo laptops and other devices (affiliate link).

whatty

42 posts

Geek

#157807 18-Aug-2008 20:07

Guys as long as you are only talking only about the Olympic coverage especially the cycle track coverage, I can assure you it is the Host broadcaster and the OB truck end with possibly some wireless breakup and not the zinwell box or NZ TX via Freeview.

sjadd

61 posts

Master Geek

#158187 19-Aug-2008 23:12

whatty: Guys as long as you are only talking only about the Olympic coverage especially the cycle track coverage, I can assure you it is the Host broadcaster and the OB truck end with possibly some wireless breakup and not the zinwell box or NZ TX via Freeview.

Well like I said I ran a side by side test with the DSE/Zinwell and an HVR2200 and only the DSE glitched. But yeah, have never seen it glitch in ads or non-Olympic coverage so who knows?

richms

29098 posts

Uber Geek
+1 received by user: 10208

Trusted

Lifetime subscriber

#158190 19-Aug-2008 23:34

Are you people with the issues outputting at 720p or having the box downconvert to 1080i only to have your screen deinterlace it again?

Richard rich.ms

samj

8 posts

Wannabe Geek

#158195 19-Aug-2008 23:56

I noticed that it does it on the HD Demo channel too on part of the Poseidon clip with lots of flashing light (the disco scene).