HDV in the preview window.

epirb wrote on 2/8/2005, 2:11 PM
I just noticed that when using clips with the CFHD interm. that when I set the project properties to the HDV 60i setting that the preview window has noticeable verticle banding or blocking across the screen. If I set the project to the HD setting it lokks great. The clips properties show the as HDV with a par of 1.3333 and thats the settings on the HDV set up but when I go to the HD set up with a par of 1 sqaure it looks better. I did a screen cap of each setting then imported the png into PSP. and they look the same, no verticle streaks.
Is this a porblem with my vid card or some settings?
farss or Spot can you tell me if its doing the same for you?

Comments

Spot|DSE wrote on 2/8/2005, 3:34 PM
Project should be at HDV setting, preview window set to Preview/auto.
Otherwise Vegas is rescaling everything.
epirb wrote on 2/8/2005, 6:24 PM
yeah thats what I figured just kinda wierd that I get those lines.
Dont know what to make of it.I'll have to try some short renders to see if it affects the output, I doubt it will.
Spot|DSE wrote on 2/8/2005, 6:32 PM
It won't. It's just how Vegas is downscaling the image, plus in NTSC-DV mode, you're in lower field format, whereas HDV is upper field first. So, you'll see some interlacing weirdness.
farss wrote on 2/8/2005, 7:07 PM
Hm,
we shot our first gig in HDV last night, Tosca at the Sydney Opera House, those guys sure know how to light to stress video.
Anyway we also shot on JVC 500, the HDV stuff is just a trial at the moment.
Latitude wise it held up pretty well, however like epirb I'm having the same issue.
I captured with CineformHD, both the native .m2t and had it converted to the intermediate codec at medium file size. At Best Full there is very noticable artifacting on some vertical edges, seems to affect highlights more than anything else. I tried downconverting to PAL DV 16:9 and thta has the same problem so I can only assume it happened during the encoding.
I've left the machine running doing the conversion again at Large, see if that makes any difference.

One question, when I render out to DV will the field order be taken care of correctly, I seem to recall there was an issue with this?
Bob.
Spot|DSE wrote on 2/8/2005, 7:16 PM
Farss, I've not seen this, but I've read about it on several forums. Is this related to dark imagery that the compression is doing something with? If it's in the m2t, it's not Cineform causing it, but there is another guy in one of the forums that says he can't see this in the transport, just in the DI.
I'm gonna go shoot some fence posts in the dark to see if I can figure out what's happening. I've asked the guys at Cineform to chime in too. Is this seen during still shots, panning, zooming?
farss wrote on 2/8/2005, 7:33 PM
The scene is fairly dark (hey it's opera) but the shot is static and the object is a statue! It's NOT in the m2t, that looks STUNNING! But VERY slow to deal with. The DI plays fine just this aliasing issue.
I could use the DI as a proxy and work that way, but I was under the impression that the DI should give better performance quality wise but it sure doesn't look that way to me. However it is only a medium size file, I'll have to wait and see how the Large size transcode turns out.

Bob.
David Newman wrote on 2/8/2005, 9:55 PM
It is likely to be a display on issue due to preview scaling -- this will not effect output quality -- yes this DI should enhance quality and performance. I don't believe this is a compression artifact, after all the same codec has been around of 18 months and used for a 35mm film out without report of any such artifacts. Still I would like to get to the bottom of this. Can someone do this test -- export a frame from the M2T source and export the same frame from CFHD, open these image files with a non-scaling viewer (IrFanView is a great choice.) If the error is still visible (ignoring the color error of the M2T file) please email me both images (preferrably as PNG images for lossless without the size of BMPs.)

David Newman
CTO, CineForm
farss wrote on 2/9/2005, 12:26 AM
It'll be 24 hours before I can it but no problem. I agree, kind of hard to believe it really is a problem, I was 100% certian it was a preview issue until I did 2 things:
1) Rendered to PAL DV 16:9 and it was the same.
2) Replaced the .AVI file with the .m2t in the same project and the aliasing was gone.
Bob.
epirb wrote on 2/9/2005, 4:03 AM
David If you'dlike I can send you some .pngs as well as a screen cap pf the issue tonight. I will do some renders as well DV wide ntsc. You can send me your email address at epirbATcomcastDOTnet.
Eric Stammer
farss wrote on 2/9/2005, 4:48 AM
I cannot be 100% certain until tomorrow if I was using the correct project template, perhaps I was using 1080i HD rather than HDV but still I don't think I should have been seeing what I was seeing and it doesn't explain why replacing the avi with the m2t stream changed it dramatically.
Ah, the joys of the bleeding edge.
Bob.
Costis wrote on 2/9/2005, 9:29 AM
""Project should be at HDV setting, preview window set to Preview/auto""

Ok, but the preview image is stretched then, is not 16:9. That is in both settings, 1920/1080 and 1440/1080. What is the correct project settings anyway?
Spot|DSE wrote on 2/9/2005, 9:32 AM
The correct project settings are part of the Vegas 5d upgrade (free download) and you'll want to be using the HDV preset for 1080i and the framerate you're working in. Keep preview window set to Preview/Auto. The image is not stretched, it's accurate.
Costis wrote on 2/9/2005, 12:46 PM
You mean the 1080-50i (1440x1080 25) preset or the 1080-60i (1920x1080 25) one?

Tfe first gives me a 1.4/1 image, the second an almost 2/1 image. Both with 1.33 pixel.
What am I doing wrong?
farss wrote on 2/9/2005, 5:57 PM
Just got back from having another look at this, it does seem to be a Vegas and not CF issue.
Using HDV 50i template the m2t and avi DI are the same. Setting preview window on second monitor to Preview Auto and selecting Simulate Device Aspect there's very noticable vertical tearing. Turning off "Simulate Device Aspect" clears the problem so I think I can say it isn't a codec / camera issue.
However no matter what I set preview to I cannot get a clean correct AR preview off the DI but I can off the m2t I think, this is very odd. At the moment I'm trying encoding from the DI to 16:9 PAL mpeg-2 for a DVD at Best, we'll see how that goes. Once that's finished (yes this takes a lot of time) I'll play with the preview problem some more.
I suspect this isn't a problem new to HDV, I've had the same issue with text for example, it can look real ugly on the preview with SDA on (even at Best) but looks fine on the external monitor. Where it does become a problem with HDV is the internal monitor is ALL we have to work with, maybe the interpolation algorthms used to adjust AR for the internal preview need some tweaking. I also suspect with DV25 this is more of an issue in PAL than NTSC, on the odd times I've work in NTSC the preview with SDA on looks much better than it does for PAL (lower res of NSTC taken into account).
Bob.

PS, before anyone jumps all over me here, please, please check things in a PAL project!
epirb wrote on 2/9/2005, 6:10 PM
I too am trying a couple of things but my wife is using the computer for work stuff, and i'm still not finished building my HDV PC.
farss, did you notice that if you change the project prop to HD the preview window looks great, but plays about 1/2 the frame rate of the HDV codec. assuming its because of the par and frame size difference.
epirb wrote on 2/9/2005, 6:14 PM
monica, just to be clear a couple of questions:
are your clips PAL or NTSC?
you have the template set to the HDV 50i for pal or HDV 60i NTSC yes?
you have the preview window set to preview auto and not full?
and simulate device aspect ratio selected?
farss wrote on 2/9/2005, 6:43 PM
I'll have a more detailed look later. The boss is very keen for me to pop something / anything out asap as he wants something to show off to the client I think.
Bob.
Costis wrote on 2/10/2005, 4:15 AM
epirb,

my clips are PAL. I tried both templates, both gave me distorted preview (auto).

"simulate device aspect ratio"- where is that?
farss wrote on 2/10/2005, 4:18 AM
R click in the preview window.
Bob.
Costis wrote on 2/10/2005, 4:49 AM
thanks, it was checked already. I have the same 1:1,89 ratio in preview. Larger than 16:9. Anyway, should I select 1080i-50 template (1440x1080) and 1.33 pixel, as mentioned on an other forum?
farss wrote on 2/10/2005, 5:38 AM
Just use the HDV 1808 50i template. If you have the preview window set to Anything Full then what you see in the preview window is a cropped version, in Anything Auto it's correct AR at the largest possible size that'll fit in the window.
Bob.
Spot|DSE wrote on 2/10/2005, 5:57 AM
Monica, if you have Preview/Auto selected, but have the window very small, you'll get pixelation. Undock the window, double click the header. It will resize. See if you're still seeing pixelation.
epirb wrote on 2/10/2005, 5:49 PM
Bob could you email me at epirbAT comcast DOT net? RE this I want to send you some correspondence about this ,plus some screen shots
Also I noticed that it even affects generated media like titles on the preview window , which makes me think even more that its a Vegas issue. Spot I have had contact with David from Cineform is there somebody from sony in the loop too?