TV3 'shadow' or is it just me?

Forums › Freeview (DVB-T/DVB-S) › TV3 'shadow' or is it just me?

waldoverkill

69 posts

Master Geek
+1 received by user: 1

Topic # 25282 17-Aug-2008 16:37

I have dvbviewer and Arcsoft H264 decoder. TV1 HD looks great, SD channels look as you would expect, but TV3 seems to have a shadow trailing behind fast objects. I had recorded Outrageous Fortune and my wife and I both commented that it was slightly sickening to watch due to the fast motion shadows.

Has anyone else seen this?

Wal

AncestralGeek

91 posts

Master Geek

Reply # 157534 17-Aug-2008 16:52

From other posts on GeekZone I understand that TV1 and TV2 HD broardcasts are 720p while TV3 is 1080i. Is the shadow trailing effect present on all TV3 shows or just those in TV3 HD.

cranz

675 posts

Ultimate Geek

Trusted

Reply # 157535 17-Aug-2008 16:53

Does this also happen on C4 or TVNZ6/7?

TV1/2 are progressive scan where as all the other channels are interlaced - You could try changing your de-interlace settings to see if this helps

edit: my bad, missed the part where you said SD channels were ok

waldoverkill

69 posts

Master Geek
+1 received by user: 1

Reply # 157537 17-Aug-2008 17:33

TV3 is the only one where the effect is obvious.

The 25fps channels do not look as nice as the 50fps channels that is for sure but I don't think they exhibit the same problem as TV3. I will try another H264 decoder and see what happens.

Wal

ldarbz

3 posts

Wannabe Geek

Reply # 159609 25-Aug-2008 16:08

My picture lags behind the sound on TV3. Any ideas why?

sbiddle

27249 posts

Uber Geek
+1 received by user: 6683

Moderator

Trusted

Biddle Corp

Lifetime subscriber

Reply # 159627 25-Aug-2008 16:47

waldoverkill:
TV3 is the only one where the effect is obvious.

The 25fps channels do not look as nice as the 50fps channels that is for sure but I don't think they exhibit the same problem as TV3. I will try another H264 decoder and see what happens.

Wal

All channels are 50fps - there are no 25fps channels. Your issue is almost certainly a deinterlacing issue, what type of video card are you using?

waldoverkill

69 posts

Master Geek
+1 received by user: 1

Reply # 159634 25-Aug-2008 16:58

ATI X1950Pro

I changed the decoder from Cyberlink to CORE AVC and it is better but I still much prefer the look of TV1.

Warren

petes117

364 posts

Ultimate Geek
+1 received by user: 38

Reply # 159727 25-Aug-2008 21:58

sbiddle:
waldoverkill:
TV3 is the only one where the effect is obvious.

The 25fps channels do not look as nice as the 50fps channels that is for sure but I don't think they exhibit the same problem as TV3. I will try another H264 decoder and see what happens.

Wal

All channels are 50fps - there are no 25fps channels. Your issue is almost certainly a deinterlacing issue, what type of video card are you using?

Watching The Bourne Identity on TV3 tonight, and DVBSource says that its playing (or receiving? what is DVBSource anyway?) at 25fps. Even though The EVR renderer says I'm getting it at 37fps. Could be some confusion there ;). Other channnels usually say 50fps in DVBSource.

I used to get really bad ghosting in TV1 and 2 as well until I updated my DVBViewer version. Make sure you've got v3.9.4
Though I still get ghosting it on TV3!

Hope that helps :)

sbiddle

27249 posts

Uber Geek
+1 received by user: 6683

Moderator

Trusted

Biddle Corp

Lifetime subscriber

Reply # 159729 25-Aug-2008 22:06

It says 25fps because it's an interlaced channel. 2 x 25fps = 50fps.

Your main problem is that you don't have a GFX card that supports h.264 hardware acceleration. To be completely honest you stand absolutely no chance of getting a decent picture on TV3 unless you have a video card such as a NVidia 8500 or higher that supports onboard H.264 hardware acceleration. Trying to get a decent picture of TV3's 1080i feed with a software based codec is just a complete waste of time.

TV1 and TV2 are transmitted in 720p so there is no deinterlacing required once the picture is received. This is why IMHO 720p is a far superior standard to 1080i - when all TV's these days are progressive scan it seems absolutely crazy we're transmitting interlaced video that was designed for a CRT TV.

jeavons

19 posts

Geek

Reply # 159730 25-Aug-2008 22:07

Make complaint to TV3, and get them to change their system to 720p

petes117

364 posts

Ultimate Geek
+1 received by user: 38

Reply # 159734 25-Aug-2008 22:17

Ah thanks for clearing that up sbiddle!

I still noticed a big difference with ghosting on TV1 and 2 after upgrading the DVbViewer software though. Worth a shot!

Agreed TV3 should pick a side, 720p or 1080p, none of this 1080i business.
Is 1080p even possible over DVB-T?

sbiddle

27249 posts

Uber Geek
+1 received by user: 6683

Moderator

Trusted

Biddle Corp

Lifetime subscriber

Reply # 159737 25-Aug-2008 22:21

gurthang117: Ah thanks for clearing that up sbiddle!

I still noticed a big difference with ghosting on TV1 and 2 after upgrading the DVbViewer software though. Worth a shot!

Agreed TV3 should pick a side, 720p or 1080p, none of this 1080i business.
Is 1080p even possible over DVB-T?

1080p is theoretically possible over 1080p but the reality is 1080p will never be a broadcast standard, simply because of the bandwidth requirements. Nobody's broadcasting 1080p other than some trials that have taken place. 1080p will only ever be a Bluray/IPTV/internet download format.

If you're getting "ghosting" on TV1 and TV2 my guess if your PC is trying to deinterlace a progressive image which is causing issues.

aucklander

379 posts

Ultimate Geek
+1 received by user: 3

Reply # 159807 26-Aug-2008 10:16

sbiddle:
IMHO 720p is a far superior standard to 1080i - when all TV's these days are progressive scan it seems absolutely crazy we're transmitting interlaced video that was designed for a CRT TV.

I perfectly agree with this !! Why two standards on a small market, with only three channels (partially) HD?

And one more thing difficult to understand: if the signal contains 720 lines, why on Earth do "they" manufacture / promote / sell screens with 768 lines ???? At the end of the day, we want progressive, but it comes in 720 lines only. So you have to do an upscaling using a $5 chip in the tv. Same happens in an 1080 tv.

Avoid upscaling using 1080i on a full HD screen? You hit the "de-interlacing" wall at full speed.

Why 1080i on a tv? This chart shows full benefit from having 1080 (over 720) is achieved when viewing distance is approx 1.6m for a 42" screen (or 1.8m for 46"screen). I really do not believe there are people really watching tv from so close, for hours at a time, day after day. I have a 46" (768 lines) and my eyes are at over 4m from the screen when watching tv. Please note the chart compares 720p with 1080p (much smoother I believe), not 1080i.

my opinion: 1080 screens are a marketing stunt. If you watch tv from 1.5m away on a BluRay, then it might be fine. But how many do? (the average person cannot lie in bed and do this unless your feet go under the tv !!) And one more thing: imagine the motion sick you get if the image is not REALLY smooth when watching 46" from 1.6m away!

mobo Intel DH55PJ, RAM: 4GB RAM, Nova-T 500 HD + Avermedia Trinity tuner card, Geforce 520 video, 120GB SSD Sandisk + 640 WD + 1000SG, Win7 Home Prem 64-bit, Media Portal 1.15.0; BTC 9019URF Cordless Keyboard, Panasonic 55" (HDMI cable), HTPC Case Silverstone Grandia GD05B.