Hi Everyone!

I've got some footage of a person dancing in front of a pale (almost white) wall. I need to basically do the whole iPod ad thing and get a black silhouette of the person with a transparent background as a PNG sequence. That image will then get manipulated around, and be used in an animation sequence.

Tried luma keying in FCP, but the results were pretty poor.

I've started manually rotoscoping in Photoshop 7 (on PC). Done about 209 frames so far. It takes me about a minute to do one frame. I'm just using the magnetic wand tool and some actions to speed things up. The cutting out doesn't have to be 100% accurate, as the silhouette gets an 8px Gaussian Blur and a 30% opacity (basically it looks kinda like a shadow).

However, I've still got about 600 frames to go!

Is there a better/quicker/easier way to do this?

The Photoshop method works fine - but if I could develop some automated way to do it, well, I'd be in heaven!

I've got Photoshop CS, Final Cut Pro, Shake and After Effects 6.5.

Should I continue with the Photoshop method or try something else for the rest of the frames?

Any suggestions for rotoscoping using Photoshop? I've tried plugins like "Snap" and "Fluid Mask", but they just slow things up.

Oh, and also, does anyone know how to get a batch capture working, with actions that have "Stop's" in them?

Thanks in advance!

Chris!

Hi Everyone!

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Thanks in advance!

Chris!

Post me 10-15 frames as a quicktime/image sequence/anything useable and I will have a quick look for you if you like, I have a few ideas.

Thanks Lee!

Download Link: http://hyperupload.com/download/02f71f7611/Sample_Footage.zip.html

Photoshop 7 Questions:

1. Can you "launch" an image to Photoshop from Windows Explorer that automatically runs an action when it opens? For example, is there a way to make it so you can right-click on a photo icon in Windows Explorer and select "Open With Photoshop (Run XXX Action)"?

2. Is there a way to make an Action that Selects the Magnetic Lasso tool?

3. As asked in the orginal post - anyone know how to run a batch capture that contains an Action script that has "stops" in it?

1. Yes, using a droplet; look it up.
2. I have not tried, but it should be possible. Why don't you try?
3. You can make an action pause by "ticking" the command on the action list.

I think the easiest way to do this is to use high contrast lighting on a greenscreen. I looked at your samples, and the mistake you made was to light the subject. Place the subject in front of the background light. It would be easier to reshoot it than to slug through rotoscoping your existing footage.

Thanks for your reply Emre!

1. Cool. I'll look into it.
2. You cannot record it as an action. For example, if you record a new action, when you click on the lasso tool, Photoshop doesn't add anything to the action list. I was hoping there might be a way around it. Maybe using the menu functions?
3. Sorry, I don't follow you. Could you please explain? The only tickable options in the action list I can see are the toggle on/off.

Yes, I understand that there are plenty of more convenient possibilities if I re-shot. However, in this case, it's not possible.

Thanks Emre for introducing me to droplets! Very handy!

Ahhhh, I see what you mean now Emre in regards to the "action pause"...

For anyone who's interested, after a lot of playing around and testing various different methods using all kinds of weird and wonderful programs, I ended up with the following workflow:

In Final Cut Pro I used Colour Key Filters (15 of them actually!), Keyer, Blurs, Garbage Mattes, Colour Smoothers, etc. to get rid of the background. It actually did a really good job! I was really surprised. If at first you don't succeed, throw in another couple of colour keys! This left me with a cut out person dancing, and a transparent background. I then exported as a TIFF sequence, fixed up some frames manually in Photoshop, and job done!

As I had already manually rotoscoped 200 or so frames, I mixed these with the "automatic rotoscoping" footage. You can't tell the difference between the hand drawn and the computer cut-out frames.

So despite some very crappy footage, with a bit of stuffing around, I got it working.

Thanks Lee & Emre for your time!

Oh, and despite the fact that I've done what I needed to do, if you can come up with a better/different/cooler workflow, please do tell and post your results!

hi chris: i've been following your thread because i need to do something similar, so i have to second your request...

if anyone knows how to do this effectively and minimize the workflow to creat that ipod effect of a shadow figure, please by all means, chime in!

Like I said:
I think the easiest way to do this is to use high contrast lighting on a greenscreen. I looked at your samples, and the mistake you made was to light the subject. Place the subject in front of the background light.

Emre's absolutely correct.

Use someone with black hair, wearing black clothing moving in front of a green screen. A color difference key will be nearly automatic, and work well even with DV color compression.

Then use that key as a mask for a black solid over a color background and you're good to go.

Chris Hocking Sorry didn't get around to looking at your sample ! Too busy !!

Glad you sorted it out.

Emre's absolutely correct.

Use someone with black hair, wearing black clothing moving in front of a green screen. A color difference key will be nearly automatic, and work well even with DV color compression.

Then use that key as a mask for a black solid over a color background and you're good to go.

Like Nick said above, this is pretty much the best technique, you could even go as far as blacking up the face and hands of your actor whatever his starting skin colour.

Also when green screening - softening the chroma (colour) of your DV/HDV signal can realy help.

You can do this very quickly in After Effects (or Photoshop if you 'batch') it realy helps with keying. And it takes no time at all the render!

1 - Stick your HDV or DV footage on the time line (in a composition).

2 - Make a new 'solid' to the size of your composition and stick this on top of the footage.

3 - Set this new 'solid' to be an adjustment layer by clicking on the adjustment layer switch.

4 - Set this adjustment layers' blend mode to 'color'

5 - The add a small gaussian (4 - 8) blur to this adjustment layer.

Hey Presto! you have control over your chroma, you can soften just the colour without making the video any less sharp.

Here is an example of Bad DV I have used this technique on.

http://img182.imageshack.us/img182/8752/chromabluryp7.jpg

The top half is the RGB composite image before and after, which is not noticeably effected by the adjustment layer, the bottom half of the image is the blue channel before and after.

___

This effect is EASILY replicated in shake, and since you have it then you should be good to go.

Take your footage, add a CFC Keylight. Under image, add a color...something like the bright backgrounds. Key out your white in the CFC keylight. Then under Layer add an Over to re-composite.

From there, with your keylight selected under Color go to Saturation and bring the value down, then still with keylight selected under color add a contrast luminence bring up the center and bring down the value.

You can also add a garbage matte if your footage isn't perfect.

This should work, depending on how good your keying footage is but is the best way IMO to do the Ipod Effect.

Thanks EVERYONE for your comments and suggestions!

I understand that shooting against a blue/green screen would have achieved the best results (and even better if the person was wearing a "black suit"). However, as I said, in this case I just had to work with the footage I had. Not ideal, but it actually worked pretty well in the end!

Lee, thanks for your "softening the chroma" technique! I'll give it a test drive sometime!

Harrison, thanks for your advice. I haven't had a chance to really get my head around everything Shake has to offer as of yet. I will definetely try manipulating this footage with only Shake sometime soon. From what little I've done with Shake (mainly just subtle little things - no keying, rotoscoping, etc. yet) I must say I really love it. The interface is fantastic, and I really love the 3-mouse button control. Trouble is I then send the footage back to FCP, and get annoyed when the middle button doesn't do anything! I just need to spend some time playing with it. I can't wait to get stuck in and attempt to become a Shake guru.

I'm sure you could also achieve the same results in AE.

But in this case, with limited time, and as I've never really used AE or Shake for keying, it was easier/quicker just to use the FCP tools I'm familiar with.

Again, thanks everyone for your help.

Chris!

I shot a commercial where I had to cut-out the subject and place her in an all-white set with some graphics moving behind her. I chose to shoot in front of a bright white set rather than blue or green screen due to the fact that I was shooting on DV and I havent had good keying on DV footage, so by shooting in front of a white screen, the keying doesnt have to be perfect for it wont be noticed on the virtual white set.

I get good cut outs using After Effects 6 or 7 with only one Color Key. Whenever I get an undesired cut-out on the subjects bright spots, I just mask that hole out...

I'm a little late jumping in here but if the camera was on a tripod, and stationary, wouldn't the "Difference Matte" do the job? I have not used it but my understanding is that its perfect for removing everything in a clip that remains the same, like on a stage.

If you start filming with only the stage and no actors, then when the actors come onto the stage they are the only new information in the clip and only the actors will show up with this filter. Frequently a still image is taken from the clip of the stage and this clip is on a layer by itself, the length of the entire clip. The overlying clip is compared to this image and only that which is different (ie; the actor) between the clip shows up. Everything but the actor would be transparenta.

Anyone ever use this filter?

I've tried using this kind of feature in the past with a variety of different software applications, but have never had much luck with it. Chroma keying has always worked out much better. But I'd be very interested to hear if others have had any luck with a difference matte approach. I do intend to have another go with it in the future though...

Oh, and by the way, in the end, despite the good results I got using FCP, I ended up just manually rotoscoping the whole footage, thus achieving the perfect matte.

To Charley:
The problem with the difference key is the noise. If you have a "really" good footage without any noise your key will be good, otherwise the noise will be interpreted by the keyer as a difference and the result will follow that.

To everyone: If your background is white (or black) try the extract keyer that is developed specially to make extractions with B or W backgrouds.

I forgot,
even if you have a "near perfect" situation (let´s say 4:2:2 sampling, an even blue or green with good saturation and low spill) is not very often that you can get a perfect key with only one key pass.

heres a link to an ipod spoof me and some friends did.
http://www.youtube.com/watch?v=udSp7yhvYIk

we had a blue screen, then we used green tape on the bottle to key that out as well... it was pretty complicated getting all the compositing done, but it turned out okay in the end.

I've had good results with a difference key.

Equipment used:
*Avid Media Composer recording HD-SDI to DNxHD compression. This is what I had to work with; an uncompressed FCP system should be better quality and cheaper.
*Panasonic HDC-900 camera with some HD zoom lens (it exhibits chromatic aberration)
*The subject was wearing colors not found in the background.

Good points about difference key:
*Perfect spill. You should light a difference key such that the floor, background, etc. give off the same light as your target environment. No spill suppression needed.
*May be slightly cheaper.

Bad points about difference key:
*Requires noise reduction... i.e. erode/blur in Combustion. Other effects packages should be able to do something like that.
*Requires some rotoscoping, because sometimes the colors with shadows overlap.
*Camera can't move (unless you have a motion control rig?).

?
*Motion blur was ok.
*On the HD zoom lens I used, there was chromatic aberration and that got picked up in the difference key.

I haven't tried:
*Seeing how difference key works on hair. I suspect it works poorly, since you need to erode + blur the alpha matte.
*Lighting a green screen really dark (to solve the spill problem), and using a combination of color keying + difference key techniques.

I'll ad my experience in this if it's any help. I've done videos where I'd key out liquid (Luma) and people (green screen). In AE DV matte worked great, but NOTHING could key that liquid. So I did all my Luma keys in Final Cut and was surprised how perfect I got it. With a performer being keyed out the exposure would need to be perfect, and if it's DV someone told me 24p is best.
But green screen is better because if it's like the ipod ads they'd be black and white, and you wouldn't need to worry about the green reflecting.