HV20 working out well for greenscreen!
 

Hey all,

I'm working on a new version of dvmatte pro, and so far, the HV20 is really faring well! Check it out here...

A couple notes:
I'm currently evaluating different image controls on the HV20 to maximize the results for greenscreen. So far I've been using a "Custom" image setting, but I'm going to do some tests with the "Low Sharpening" mode soon. The custom settings I'm using right now are Sharpening -1, Contrast -1, Color -1, Brightness +1... I'm also shooting in 24p, and using the Cine setting. Those Custom settings combined with the Cine look gets you the lowest-contrast image out of this camera, which is invaluable when doing further processing... Also, the miniSD trick really helps when you're doing keying, because you want to be at 0db gain.

I'm frankly pretty blown away by the image quality on this $900 palmcorder... The times, they are a-changin'...

- ben

Someone asked about my greenscreen setup -- I shot this against two pieces of fluorescent-green posterboard taped together. For headshots, this stuff is actually pretty nice. It's a very bright green, which is just what you want. And you can't beat the price, at $1/sheet. :)

Good deal - i've had very good results as well capturing HDMI.

Are you going HDV or HDMI?

HDV -- I don't have a way to capture HDMI yet. I'd be curious to compare the two. Although I don't think the HDV compression is the limiting factor anymore...

that looks really good! ill have to check out your keyer sometime.

Thanks Adam! This new version will be a doozy.

I'm impressed the HDV did so well for you!

However, capturing with CINEFORM is immensely superior - if you ever get the opportunity i'd definitely give it a try!

I'm not familiar with how a keyer works but I was thinking that you could only use them with pro cameras. Where can I get some information on the dvmatte pro?

Yeah, a lot of people assume they can't do greenscreen unless they have a high-end camera, but you can get some great results with small cameras these days!

dvGarage distributes my stuff, but I'm about to release a new version -- check the site in a couple weeks!

I didn't realize you wrote this stuff. I just looked at the dvmatte products on the dvgarage website. Very impressive!

Very impressive for an inexpensive camera and impressive software too.

Ben,
I've been considering experimenting with no budget greenscreen work for a long time and would like to go into this. Especially because, with no budget, you need all the help you can get to make your film look more than it is -- and greenscreen is a marvelous way to do that (with no boundaries!). When I have time I'll sort out my plans and get your software.

sorry to go off topic, but is your LinBayer software still available? I know several years ago you were experimenting with a Sumix camera head -- there's a new one out with a credible sensor (look in the Alternative Imaging section). Your program may be of interest to the people on that thread...

Regards,
John.

cool, ill be checking back soon. need to try that posterboard idea too, looks like it gives good results.

Definitely -- greenscreen has become routine for even non-effects movies in Hollywood, and I'd like to see indies have the same flexibility!

Geez, I don't even know where LinBayer is in my archives... It wouldn't be hard to replicate that work. It was basically a logic-based debayer algorithm on top of a pretty basic two-pass 1D interpolation (spline?). The logic-based bit was good for pixel-level detail, but it freaked out when it encountered moire, noise, or fine detail past nyquist.

These days, I'd probably strip out the logic layer and just work on getting the best possible interpolation.

Incidentally, it would be very easy to write a GPU-accelerated bilinear debayer plugin for previewing raw footage -- it would run faster than realtime on most systems...

Ben is the new version of dvmatte pro Mac-only?

Yeah, I'm focusing my development efforts on Final Cut Pro right now. FCP has an amazing realtime processing path, and it's very accessible to developers...

As a long-time DV Matte Pro user, I am very excited about what I'm seeing there for the new version...

I'm also considering an HV20 as a second camera... so it's nice to know that it will capture chroma-keyable footage okay.

This new version is a whole new world... and the HV20 is an awesome machine!

Are you going to have a new version for After Effects or Premiere Pro?

Maybe at some point, but not right away... I'm moving away from traditional CPU-based effects. Once you see a MacBook Pro playing back a 720p dvmatte pro composite in realtime -- and you're able to tweak dvmatte parameters as it's playing -- After Effects begins to look extremely unappealing.

Your hair is transparent.

Maybe you have thinning hair too like me.. ;)

Yeah, I might have gone a little too light on the hair... there's a slider that lets you adjust how dark those fine details are.

Very nice. I'm going to have to give the new version a hard look. Will you post back here when it is available?

Your sample was scaled down to SD. Do you really think that at HD dimensions the added color resolution of straight HDMI capture (4:2:2 vs HDV's 4:2:0) won't make a significant difference in edge quality?

Joseph,

The sample I posted is in HD resolution -- to see the full 720p, make sure you have the "HD on" button toggled in the Vimeo player. You probably want to hit "full screen" too...

You'll probably see a small advantage from capturing to HDMI, but for most subjects, the pain of shooting tethered to a desktop machine with an HDMI board won't be worth it. I know I'd rather shoot to tape or to a laptop... :)

Found the Quicktime at the bottom of the screen.

Very nice raw results. With the right lighting and the appropriate bkg plate you defintely could make tricky composites that sell on screen, even with HDV.

Please do let us know when the new version ships. Do you have a list of the improvements anywhere?

Not yet, but the improvements are basically:

- Vastly improved fine detail response. It's now possible to preserve even the finest details. Tiny wisps of blonde hair can be reproduced.

- Dynamic spill suppression. Normal spill suppression corrects the green of the greenscreen to one specific color -- usually a brownish gray. The new dvmatte considers the background when de-spilling, changing the spill parameters on a per-pixel level.

- When compared with older versions of dvmatte, the new version is somewhere between 10 to 100 times faster, thanks to GPU acceleration. You can key 720p footage in realtime on a laptop!

That's some list!

:)

In the past, the software was really the limiting factor. You could have pretty good footage, but not be able to make an acceptable composite. But with this new version, I think we're finally brushing up against the limits of the greenscreen process itself...

The new fidelity of the process can be a double-edged sword; reproducing all that subtle detail means we're also reproducing any tiny mistakes or problems. The new dvmatte will render even the finest wisps of hair, but if you're not careful, it can also faithfully reproduce vignetting, uneven lighting, camera noise, and tiny screen imperfections. If you use a cloth greenscreen like I sometimes do (the ones from Composite Components are the best on the planet), you have to be careful when shooting HD, because dvmatte will even reproduce the fine weave of the fabric!

Of course, I have tools in the dvmatte toolbox to deal with that, including a screen correction plug-in, and a screen cleaner that scrubs away detail from empty areas of the screen. But the less work those plugins have to do, the better.

It'll be interesting to see how people take to this new version -- it shifts a lot of weight from my shoulders to the person lighting and shooting...

When will it be available?
 

Hey Ben, the new version looks awesome!!! Do you have any idea on when it will be available for purchase, and what it will be called? I'm anxious to get my hands on it.... Thanks!

Stefan szabo

Thanks Stefan!

From what I gather, we're set to release sometime late this month or early in December. It'll still be called "dvmatte pro," and will still be distributed through dvgarage.com

What bit depths will the new version of dvMatte Pro support -- full 32-bit floating point? What resolutions? And will there be a Windows version at some point?

Lawrence,

The plugin will run at 32bit floating point, but there is no benefit to doing so. Internally, the plugin operates at 32 or 16 bit floating point, depending on the graphics card present. So even working with 8 bit footage, you get the precision of floating point.

The resolution is limited by what the graphics card can handle. Most cards are 2k at this point, but some new cards have 4k support.

It's sounds like the newly announced FCE 4 supports the same plug-in architecture.

Ben,
Do you think it's likely that the new dvmatte will function in the new Express?

Joseph,

I haven't done any testing with it, but FCE does support FxPlug, which means dvmatte will probably run great!

24p process question
 

Hi Ben,
I do a lot of chroma keying and just purchased an HV20. Your dvmatte sample looks great!

Can you please tell me if you recommend using the 24p mode or the normal interlaced mode for chroma keying with the HV20?

If you recommend 24p, can you also please let me know which process you use for encoding the video with the HV20 (i.e. do you get true 24p with the reverse telecine)? Are you using Apple's method (in link below)?

http://docs.info.apple.com/article.html?artnum=306389

I have an important project coming up, and I want to be sure everything will work properly.

Thanks!

- Kent

Hi Kent,

Cool! You won't be disappointed. The choice of 24p or 30i will really depend on the rest of your project, since you presumably want the greenscreen stuff to fit in with your other footage...

That said, progressive footage may have the edge, because interlacing really stresses the MPEG codec used in HDV. Also, 24p is more sensitive to light, so the camera won't kick on the gain as quickly.

I do use that Apple technique to convert the footage to true 24p. It works great!

Hi Ben,
Thanks for the info. I am actually using the chroma footage in a Flash program, so progressive seems best.

Thanks again!

- Kent

Ben - I purchased an Intensity card to use with Final Cut Studio 2 and the HV20 for green screens.

1. When I capture at 1920 x 1080 60i 'live' from the HDMI (to ProRes 422 HQ), exactly what am I getting? I get very different feedback depending on who I ask.

Is it 60 fields, each recorded at 60 distinct intervals per second (no field matches the time of any other)?

Or, is it 60 fields, with 2 field recorded at the exact same time, the frame broken up into even and odd fields so that it can be packaged in 60i?

2. If I capture 24p HDV, encapsulated in 60i, what am I getting? Are there 48 fields (odd and even) captured at exactly the same instant, but packaged into a 60i stream with the pulldown frames added?

In other words. Is it progressive for HDMI capture? Is it progressive for HDV 24p capture? But, all packaged within 60i?

3. Are there any settings on the HV20 that will affect the output when capturing thru HDMI? I'm really hoping that with the better color space - and no MPEG compression, I can get better output.

4. Any word yet on when your new version of dvMatte Pro will be out?

BTW - it would be nice to have a 'versions' page on the dvgarage.com site. I have no idea what version is currently shipping, the bugs fixed in previous versions, etc.

1. When capturing 60i, each field is a unique moment in time, each field is different. This is easy to see when you step through your deinterlaced footage.

2. When capturing 24P, each combination of fields is a discrete moment. The sensor is truly progressive.

3. Whether recording to HDV or going out the HDMI port, the 24P is encoded into a 60i stream.

4. Most, if not all, of the HV20's image settings affect the HDMI output. If you think about the image chain, the HDMI output sits immediately before the HDV compression.

5. You're gonna want to keep all of the image settings at 0 or -1. Especially SHARPNESS if you're keying.

Joseph - why in the world would they use a progressive sensor and muck it up by taking 60 distinct fields? They could have packaged this as 30p in 60i, couldn't they?

You seem to be saying that 24p is possible out of the HDMI?

Is there a way to get 24p, or any true progressive stream - out of the HDMI with a 'live' capture? Or, am I stuck with 60 discreet odd/even moments in time that won't exactly ever fit together properly?

BTW - if you happen to be a FCP user, any tips on the best way to de-interlace the 60i HDMI, if what I'm stuck with are truly 60 distinct moments in time, how can you de-interlace something where the parts are not meant to fit together?