Big square pixels on DVX footage

M

MeAgain

Carbonite Member
I tried searching around for this problem, but there are a million pixelation-related or "my footage looks bad" topics on here.

I think this might be a problem inherant to the DVX, but I DID notice my first little dropout on footage yesterday, so i don't know if it has to do with the heads-

Anyway, I shot some stuff today outside, reviewed on location and it looked fine. I brought it into FCP 7 via firewire (with NTSC/24pA capture settings) and the footage looks awful, especially compared to other stuff I shot. If I zoom in 400% in the viewer on the footage I shot outside, I can see a LOT of video artifacts and blocky pixels. If I zoom 400% on some other stuff I shot a few weeks ago, it's grainy but not blocky.

I'll attached some pictures. If you zoom in on the girl's hair as well as the tree, you'll see what I'm talking about. Is this just inherant to the DVX and the way it handles detail, or is there something wrong with my heads?

The first two pics are from the outside shoot, the third is from the footage that DOESNT look blocky. I used the same settings for all threww grabs:

-24pA to tape (with removed pulldown)
-THIN detail
-Normal Matrix
-Cinelike Gamma
-Detail Level -5
-A. Iris 0
-Master Ped -10

It's on the original dvx in 4:3 aspect ratio. If this is inheriant to the DVX, I'm hoping Neat Video can help me smooth it over.....
 

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I tried attaching it, so I'm just linking it here. You can REALLY see the problem in the girl's hair and jacket. (In the BW pic, the noise on the left side happened during the png conversion, so ignore it.


sequence1.png


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sequence2.png
 
I'd also like to add while I've seen these types of problems with the really bright colors and diagonals, this seems like a worse/exaggerated problem and the colors aren't even that intense...also, I plan on making the first 2 clips BW like the third one, but it doesn't help the problem either way...
 
As an SD camera, I don't think you should expect it to be able to resolve all the details in the tree limbs, especially since the background is blown out (if you had a forest in the background, it might not be as noticeable, but white certainly makes it stand out).

Its just a camera limitation, something you have to learn to work around.
 
Right, but it seems aggressively bad in this footage...I mean, it's the first thing I noticed when I started capturing, because it's not on any of my other footage for the project.

If you zoom in to the color pics vs the BW pics, you'll see the BW footage doesn't have those big ugly noticable blocks, not even on the girl's coat.
 
What you're seeing here is macroblocking. Really high detail scenes, like the woman with the jacket by the tree, stress DV compression because there are a lot of high frequency elements in them. After all, there's only so much data to go around in a frame of DV footage so something has to get thrown out somewhere. Not really a whole lot you can do unfortunately. If it's any consolation, pretty much all DCT compression schemes suffer the same artifacting at these compression ratios.
 
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Hm, I didn't figure on the limitations being that noticable when it broke down. Well...


Will something like Neat Video help me at all with smoothing the blocks at all? I mean, I'm more or less losing the detail completely anyway, so I can at least make the problem less noticable?
 
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