Apple Shake and HDV at DVinfo.net

Paul Ramsbottom · May 29th, 2007, 06:11 PM

TIA is anyone has any thoughts on this.

I'm using Shake a lot right now to motion-stabilize some HDV clips, using the Tracking and Smoothcam functions.

I'm seeing some nasty artifacting on some of the clips, I wouldn't say it was the normal color banding you might expect with a highly compressed format like HDV but rather a cubic pattern that appears uniformly accross the image (but is more obvious in areas of uniform color.)

Oddly it seems to be more prevalent, when I am correctly clips with a very small amount of motion, by this I mean I get better results when there are a lot of moving elements in the scene (traffic, people etc.). It's the static landscpes, where I need to remove a little camera-shake, that seem to suffer the most.

Any thoughts?

Thanks,

Paul.

Cole McDonald · May 29th, 2007, 07:36 PM

Are you shooting pregressive or interlaced...if interlaced, are you de interlacing when you pull it into shake? Could you post a screen grab of the problem?

Paul Ramsbottom · May 30th, 2007, 04:24 PM

Thanks Cole, so it would seem that HDV isn't properly supported by Shake.

As per your suggestion, I converted one of my 1080/60i HDV clips to a 1080/30p XDCAM format and the problem dissapeared.

Interstingly, I started my current project using [Digital Anarchy] up-rezzed SD DV clips, exported out of FCP in 1080/60i HDV format. Those worked just fine in Shake. Recently I moved onto my collection of native HDV footage, and it was then when I starting seeing these problems.

Weird that the up-rezzed clips exported in HDV format should be so uniformly free of the problems I had with the native material. Perhaps the [still] poorer quality of the SD-originated footage has somehow obfuscated the artifacts.

I'm actually doing a lot of tests, trying to decide whether to re-export all my HDV material as either XDCAM or DVCPRO HD before starting color correction. I'm thinking about buying a HVX200 or maybe the new XDCAM EX, and it would be nice to have a consistent format to inter-cut with.

Then again my budget my only stretch to a better HDV camera like the Canon XH A1, so I might sty fully in the HDV realm.

Cole McDonald · May 30th, 2007, 05:11 PM

On the filein node, there should be a button to deinterlace...or you can add a deinterlace node to do it right within shake as part of the workflow so you don't have to convert everything. It'll streamline your workflow and uses the same engine (optical flow) as compressor for deinterlacing (someone correct me if I'm wrong).

Paul Ramsbottom · May 31st, 2007, 06:09 PM

Did some interesting experiments for several hours last night (yes, I have no life)

I found the de-interlace option on File-in. Can't say I explored it extensively but I did try one test.

But... I was still able to replicate the artifacting problem with de-interlaced footage that was originated from native HDV footage.

I can't really understand the entire 'story' as far as HDV support in Shake is concerned. Officially it seems that it is not supported, although there are HDV Intermediate Codec options in the format menus, and lots of reports of people using Shake with HDV footage.

That said, the issue tends to manifest itself reliably in darker areas, and static scenes with areas of even or slightly graduated color (precisely the type of image where you'd expect to see some compression-related 'banding' although these artifacts look very different (a cubic pattern that will sometimes overlay areas of contrasting tone or color).

What I have been able to consistently achieve, is an acceptable result if I first export my HDV 1080/60i clip as a XDCAM 1080/60i one (or a 1080/30p as tried previously.)

Using the XDCAM material produces much better image, with just a faint graininess (probably no more than the normal loss of resolution when you have put a clip through the Image Stabilization and SmoothCam functions).

So.... I think that basically Shake can handle the XDCAM format a little better than HDV. Feels like the artifacting I sometimes see is a result of the high levels of compression inherrent with HDV footage.

As far as format support is concerned, it's a little weird as XDCAM isn't even mentioned in the Shake format menus (at least HDV gets an Intermediate Codec 'mention') and yet it seems to handle XDCAM material much more reliably.

Think I'll wait and get that new Sony EX and not the HVX200 :)

May 29th, 2007, 06:11 PM	#1
Paul Ramsbottom Regular Crew Join Date: Jan 2006 Posts: 85	Apple Shake and HDV TIA is anyone has any thoughts on this. I'm using Shake a lot right now to motion-stabilize some HDV clips, using the Tracking and Smoothcam functions. I'm seeing some nasty artifacting on some of the clips, I wouldn't say it was the normal color banding you might expect with a highly compressed format like HDV but rather a cubic pattern that appears uniformly accross the image (but is more obvious in areas of uniform color.) Oddly it seems to be more prevalent, when I am correctly clips with a very small amount of motion, by this I mean I get better results when there are a lot of moving elements in the scene (traffic, people etc.). It's the static landscpes, where I need to remove a little camera-shake, that seem to suffer the most. Any thoughts? Thanks, Paul.

May 29th, 2007, 07:36 PM	#2
Cole McDonald Trustee Join Date: Nov 2005 Location: Sauk Rapids, MN, USA Posts: 1,675	Are you shooting pregressive or interlaced...if interlaced, are you de interlacing when you pull it into shake? Could you post a screen grab of the problem? __________________ Web Youtube Facebook

May 30th, 2007, 05:11 PM	#4
Cole McDonald Trustee Join Date: Nov 2005 Location: Sauk Rapids, MN, USA Posts: 1,675	On the filein node, there should be a button to deinterlace...or you can add a deinterlace node to do it right within shake as part of the workflow so you don't have to convert everything. It'll streamline your workflow and uses the same engine (optical flow) as compressor for deinterlacing (someone correct me if I'm wrong). __________________ Web Youtube Facebook

May 30th, 2007, 04:24 PM	#3
Paul Ramsbottom Regular Crew Join Date: Jan 2006 Posts: 85	Thanks Cole, so it would seem that HDV isn't properly supported by Shake. As per your suggestion, I converted one of my 1080/60i HDV clips to a 1080/30p XDCAM format and the problem dissapeared. Interstingly, I started my current project using [Digital Anarchy] up-rezzed SD DV clips, exported out of FCP in 1080/60i HDV format. Those worked just fine in Shake. Recently I moved onto my collection of native HDV footage, and it was then when I starting seeing these problems. Weird that the up-rezzed clips exported in HDV format should be so uniformly free of the problems I had with the native material. Perhaps the [still] poorer quality of the SD-originated footage has somehow obfuscated the artifacts. I'm actually doing a lot of tests, trying to decide whether to re-export all my HDV material as either XDCAM or DVCPRO HD before starting color correction. I'm thinking about buying a HVX200 or maybe the new XDCAM EX, and it would be nice to have a consistent format to inter-cut with. Then again my budget my only stretch to a better HDV camera like the Canon XH A1, so I might sty fully in the HDV realm.

May 31st, 2007, 06:09 PM	#5
Paul Ramsbottom Regular Crew Join Date: Jan 2006 Posts: 85	Did some interesting experiments for several hours last night (yes, I have no life) I found the de-interlace option on File-in. Can't say I explored it extensively but I did try one test. But... I was still able to replicate the artifacting problem with de-interlaced footage that was originated from native HDV footage. I can't really understand the entire 'story' as far as HDV support in Shake is concerned. Officially it seems that it is not supported, although there are HDV Intermediate Codec options in the format menus, and lots of reports of people using Shake with HDV footage. That said, the issue tends to manifest itself reliably in darker areas, and static scenes with areas of even or slightly graduated color (precisely the type of image where you'd expect to see some compression-related 'banding' although these artifacts look very different (a cubic pattern that will sometimes overlay areas of contrasting tone or color). What I have been able to consistently achieve, is an acceptable result if I first export my HDV 1080/60i clip as a XDCAM 1080/60i one (or a 1080/30p as tried previously.) Using the XDCAM material produces much better image, with just a faint graininess (probably no more than the normal loss of resolution when you have put a clip through the Image Stabilization and SmoothCam functions). So.... I think that basically Shake can handle the XDCAM format a little better than HDV. Feels like the artifacting I sometimes see is a result of the high levels of compression inherrent with HDV footage. As far as format support is concerned, it's a little weird as XDCAM isn't even mentioned in the Shake format menus (at least HDV gets an Intermediate Codec 'mention') and yet it seems to handle XDCAM material much more reliably. Think I'll wait and get that new Sony EX and not the HVX200 :)