HV20 and Blocky Images: What's going on?

Here's a raw 24P .m2t straight off the camera. This includes the interlaced pulldown (obviously). This was cine mode, 24P, 1/48 shutter.

http://www.fiftv.com/Alligator.m2tX

Download, save-as, and remove the trailing X. I don't know how long this'll be up there, that server's short of space already so this might be a temporary thing. But just so you can check and see if you see blockies in this footage; this is again raw from the camera, no recompression of any type.
 
Thanks Barry. I am downloading it now. Edit here: I don't see any signs of blockyness in the raw M2T.

Barry since you're on a PC, how are you doing the Pulldown? In what program?

Zak I do see a minor "Blockyness" in the second still. It's not as apparent as some of the others, but it exists. Is it a sure thing that it is not due to the method of pulldown?

What are the existing methods in different NLE/Programs? Since Hydra is like months away I'm back to thinking about picking up an HV20 for an upcoming project.
 
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I'm not. I haven't tried to do anything serious with the HV20, so I haven't bothered to keep up on ways to strip out the pulldown. I thought for sure Vegas would have an update that would handle it, but I guess not... I know After Effects would strip it out, if you imported the file to a composition and told it to remove pulldown and then exported as uncompressed or something, but that'd make editing a nightmare.

So I'm just waiting for Vegas to come along with the proper update...
 
I don't know, but I took those pics from Zak into PhotoShop and put one over the other so I could toggle on/off, and they look nearly identical. There's ever the slightest change in the image from the AIC recompression, but it's so very minor that I don't think I'd even worry about it at all. It certainly didn't make the footage noticeably more blocky or anything like that; there was barely any difference.
 
My early tests with the HV20 I am using Cineform Aspect HD to convert to true progressive .avi. The software is setup to remove pulldown as it captures. I have no official idea if this is the best way but usually Cineform is good about this type of stuff. David Newman suggested this himself.
 
Thanks Barry & Zak (and Kholi too for your appreciation). It seems there's no hassles, right icicle22?

Taken your previous input, any potential HV20 user would stay in trouble:

icicle22 said:
Some things to consider. I don't know if these all hold true but I think they might.

The HV20 takes a 24P stream and wraps it in a good old fashined 3:2 pulldown. This is not 24PA or 2:3:3:2 either. So, some frames are split across fields and may not be represented as a full frame anywhere. So when converting back to 24P stream from 60i there may be a loss in quality. This was the entire reason Panny had the 24PA feature. To allow the 24P stream to be represented with no individual frames having to be reconstructed using fields.

Also, the HDV codec is compressing this using 60 discreet fields instead of 24 frames like on the H1 and the A1. So the initial codec is far less efficent and will introduce more blockies as you called them. So 3.6MB persecond are split into 60 segments instead of 24 thus leaving less bits for each individual frame.

I typically edit my H1 footage using Premiere and Aspect HD. I render the final HD movie out to HD mpg files, usually around 15megabit stream. I play these acroos the network on my 45" LCD 1920x1080 screen and they look amazing and crystal clear. It is hard to differentiate them from the raw footage as far as clarity goes.

The same process with the HV20 is not as good. I can see some "blockies" here and there and sometimes can perceive a type of vertical edging. In other words certain diagonal lines show a minor stair stepping like pattern simlar to color sampling of DV. This is only prominent in less lit scenes or indoor shots. Outside and well lit scenes do not exhibit this so much.

Anyone else have any insights? Overall, technical points aside, the HV20 just doesn't hold up as well for multiple passes and editing as H1 and A1 do. IMHO.
Click to expand...

Although with Cineform I bet I wouldn't... Any thoughts?
 
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