Hi all,

Mutlichoice has recently launched HDTV via Satellite in South Africa. They are currently airing the Olympics.

Picture quality is excellent but I am having some issues...

Me and a couple of guys on the multichoice forum are experiencing what looks like frame-drops when the camera is panning on wide angle shots eg. when the athletes are running and the camera is following them the crowd in the background stutters every couple of frames consistently.

One of the posters and myself have the same setup - Sinotec (will be unknown to the US and Europe) 47" LCD with the HDPVR, Sony PS3 and Xbox 360 attached. We are not getting the same problem on the consoles.

A workaround for this glitch is to change the TV input from HDMI to Video1 and then back to HDMI - the problem disappears but if the decoder is rebooted it returns.

Now before we speculate that it is an HDMI issue - if the stuttering is occuring on the HDMI input and you switch to component (I have the HD decoder connected via component too for testing - however here it ouputs in SD) the stutter is there too. Only if you switch to video1 and back to HDMI does it dissapear.

It also reappeared yesterday when I switched between to my PS3 and back to the HDTV feed again.

All my sources are connected via a Sony STR-DG910.

I'd appreciate it if the HD guru's on this board could give some input into what u think it may be...

My speculation is 3:2 pulldown issues on the STB - it may be setting the output to film mode when the source is in fact video but corrects itself when the HDMI renegotiates OR is it an issue with the TV that is not negotiating the switch from 50-60hz correctly - consoles all operate on 60Hz.

Interested to hear your views.

Cheers
Douw

Have you tried running HDMI directly from the satellite box to the TV (bypass the A/V receiver)?

I have the same problem as DouwG - and I'm connecting the satbox directly to the TV using HDMI

Yeah - also ran it directly to the TV - problem persists.

Okay... now we're down to either the sat box or the TV.

Do you have the same sat box and/or TV?

IMO... if the problem never occurs using other HDMI sources, I'd suspect the sat box. Or... may be an incompatibility of AC power and timing (50Hz/60Hz) creating a "drift" (just a guess).

Providing the exact make/model numbers of ALL of the hardware would help.

If you both have the same TV/sat box, have you contacted either the TV manufacturer or the sat box manufacturer/provider? Perhaps they may be aware of the issue(s) and have a firmware upgrade to address the "problem".

It's kind of tough for North Americans to provide solid suggestions for those overseas. :)

Another South African here with the same HD PVR as the previous two. I have a Panasonic Plasma and am not experiencing any judder at all. Just thought I'd contribute and potentially help the elimination process :)

Trioptium has contacted the manufacturer of our TV's today and they will be looking into it for us - I have a nagging suspicion that it may be the TV but as has been pointed out - why is it not happening with other HD sources.

A good thing in a way is that we only have one satellite HDTV provider in SA so the manufacturer of the TV at least knows exactly what he is dealing with :)

On the 50hz/60hz point - it may very well be that the HDMI only sets to 50hz properly when doing the workaround - the XBOX and PS3 both run at 60hz natively and thats why we not seeing the judder there - ie. the TV switches from 50hz to 60hz properly but does not switch correctly from 60hz back to 50hz via HDMI. When you then select the video1 composite input the TV switches back to 50hz correctly. Thats my diagnosis of this problem - what do you guys think?

The STB is a Pace TDS850: http://www.pace.com/corporate/products/productDetails.asp?nav=products&productID=DSAT-TDS850

The TV is a Sinotec MP-47HU27 47" Full HD LCD TV.

Regards
Douw

Following are some factors that may be involved.
MPEG2 encoding consists of both full frame data and change to previous full frame data.
So when then there is a lot of movement or expecially panning the amount of data being received and processed is far more then when normal motion programming is occuring.
This means of course that either your STB has a lot more work to do and if it can't keep up you will get dropped frames and or stuttering.
Also 1080i programming requires more work then 720p prograqmming due to the larger buffers involved and due to the work required to do a decent job of de-interlacing.

walford - we are receiving a H.264/MPEG-4 AVC stream here in South Africa for our HD.

Walford,
Although your info is appreciated, here's a factor from the opening post:

"A workaround for this glitch is to change the TV input from HDMI to Video1 and then back to HDMI - the problem disappears but if the decoder is rebooted it returns...... Only if you switch to video1 and back to HDMI does it dissapear.

It also reappeared yesterday when I switched between to my PS3 and back to the HDTV feed again"

I don't think that this issue is related to 1080i vs. 720p or MPEG2 in the STB if it is "reset" by changing the TV's inputs.

Ratman,
I agree the statements you quote were confusing to me. My only thought was that if the STB was only being using to output composite video then the load on its internal graphics chip(s) was reduced to the point that the decoding would not fall behind since the same chip(s) was not longer be required to generate HD resolution output over HDMI.

Metoo,
H.264 compression works the same as MPEG2 as far as full and change frames are concernet. It also requires more graphic or system CPU power to decode sinc it is more highly compressed.

It will be interesting to find out the final cause of the symptoms and it appears that the local provider will nail down the cause.

Ratman,
I agree the statements you quote were confusing to me. My only thought was that if the STB was only being using to output composite video then the load on its internal graphics chip(s) was reduced to the point that the decoding would not fall behind since the same chip(s) was not longer be required to generate HD resolution output over HDMI.
Huh?
The OP clearly states he's using HDMI and his provider recently added HD. The problem persists whethe it's HD (HDMI) or SD (component). IMO... you're making this more "technical" than is needed. Sorry...


Metoo,
H.264 compression works the same as MPEG2 as far as full and change frames are concernet. It also requires more graphic or system CPU power to decode sinc it is more highly compressed.
Again... if the TV's inputs are switched (reset/resync), the problem clears. I don't think full frames or change frames are the issue. I lean towards a sync issue, as I alluded to in post #5 in regard to a 50Hz/60Hz incompatibility and/or drift. Or... hopefully as easy as a firmware upgrade (for the TV or STB). All they need is the TV or STB manufacturer to admit and address. ;)

And we will work on that admission :) and post back as to what may have been causing the problem.

Thanks everyone for your valuable input.

AVSForum for the WIN as usual.

Cheers
Douw

The provider has listed this as an official bug :) so it will be attended to.

http://www.dstv.com/Gysmm/Forum/threadView.aspx?sid=36029&Id=132

Good news... kind of ;)
Glad someone admitted responsibility and will address. Keep us updated.