Wire Removal

Well, my post on wire removal for Stop Motion Animation is finally here. If you've been reading my blog, you probably knew that I was working on a tutorial on how to do wire removal for free, which I will have in this post, but I'm also going to have a number of other links to places that you can learn more about the topic. Let's get started.

Intro
Gravity. The source of all the trouble that pops up in stop motion animation that causes the need of rigs and wires to support different objects and puppets. Without the rigging, your puppet may fall over or your ball will not be fly through the air when it is thrown. On camera however, rigging is very ugly and obvious so there is a need to remove it to deceive the audience of what was being done. Some people hide the rigging simply because they don't know how to remove it, but hopefully the links and things that I have in this post will help clear things up with you. Let's start with a few links that introduce you to the topic and how rigging is removed in live action films(the same basic process is used for stop motion)

Wire Removal in General
Fxguide has a very nice article called "The Art of Wire Removal" that tells some of the basic techniques used during the process and some of the programs that are used. This was the place where I learned the idea of how to do it in order to adapt it to Blender 3d(I use a clean plate method in my tutorial, I'll explain more later). It is probably one of the best starting places to get a grasp on things so I highly recommend checking it out. Another article I have a link to below is called "Wire Removal" by Michael Smith that talks some about the topic.

The Art of Wire Removal
Wire Removal

Cloning
One of the main ways that I started to remove wire was to clone the wire out using an image editing program. Basically you take each from in the animation and take some of the pixels around the wire and put them on top of the wire to hide it. It works sometimes, but the results aren't always the best. If the editing job is not done very well, or because of slight variations in tone and color, the area where you edited the wire out can still be visible due to flickering of color. You can do this process with any program with the right tool. Sometimes it's called a cloning tool or the rubber stamp tool. View this article on Wikipedia to learn more about the cloning tool. If you need a free program to do it, check out the Gimp. Another program that works specifically for removing wire is called Wire Pilot and works around the same lines, but is probably more suited to individual images. Both are linked to below as well as a tutorial on cloning using the Gimp.

Gimp Download Site
Wire Pilot
Gimp Cloning Tutorial

The Clean Plate Method
The second method I've experimented with and found good results with is by using a clean plate. (I actually first discovered this method watching a behind the scenes video of Narnia: The Lion the Witch...) Basically you use two images; one with your wire in it, and one of just your background(the clean plate). Each image or layer I guess would be considered a plate, and since the background one doesn't have anything on it, it's considered "clean". You take the background image and cut out a little piece of it to cover the wire with. I'm not going to explain too much more since I have two tutorials that you can look at. One is my video tutorial that I made and the other is an article done by Kyle Prohaska.

Wire Removal by Kyle Prohaska

---------------------------------------------------------------------

Before you watch my video, I want to apologize for the many flaws and mistakes in it. It's not professional by any means, but I did try my best to get the point across. Sorry for any poor pronunciation and audio problems as well. The audio is a bit off of sync and there were some issues with recording so some parts are weird. Anyways, during the tutorial I used Blender 3D to edit wire out of my animation. One thing that I did in the tutorial was save my mask, something that you need to do if you don't want to paint over the wire again. I don't remember the exact version of blender that I used, but it should work on the newest versions as well. I don't remember if there's anything else I should note. Enjoy!



Get Blender 3D Here

---------------------------------------------------------------------

That's it for my rather long blog post on wire and rig removal. I hope that you learned a lot about it and that you can use what you learned for your own films and animations. My next post that teaches something will probably be about little things that you can do to make your animation better by using a program called Virtual Dub as well as Blender 3D.

Wire Removal Test Video

Yesterday I finally figured out how to finish up the wire removal stuff. It's not perfect because of some poor masking, but other than that, it looks pretty good. I'm probably going to try to make up a video tutorial, but I can't promise when it'll be on the web. Some planning will have to go into it as well as some other factors before it will be ready. If you want to see the results I got, view the video at the bottom of this post.

To get the results I went through a few different steps:
1. Combine captured frames into an avi movie clip (Virtualdub doesn't take QuickTime files) using Blender 3d.
2. Use Virtualdub and a filter to de-flicker the video. This made it so that there would be a constant lighting. If I hadn't done this you would notice where the wire once was.
3. Change the compressor in Virtualdub to one that is compatible with Blender, then save it.
4. Use Blender to draw over the wires and unwanted objects to create a mask. Save the mask as a movie or image sequence in case needed later for further use.
5. Use Blender's node system to mask out the wires and show the clean plate instead. Do a few color corrections on the clean plate and modify the mask a little.
6. Export from Blender as QuickTime File.

If you don't understand some of that, don't worry, I plan to go over it later. I just wanted to give a rough overview of what I did to get the results. I'll probably talk about the reasons why you would want to erase wire later. Note that this is just one way to remove wire. There are others, but I found that this is pretty effective as long as your camera is not moving.

Here's the video:

More Wire Removal Testing

I had the concept down on wire removal, but I didn't really try it yet. Today I tested out the theory, and it seems to work pretty well. The only thing that is messing me up right now is flicker problems from not constant lighting that shows where the wires were. I tried concealing it somewhat using a plug-in in Virtualdub and while it fixed the flicker problem there are other abnormalities that happen because of it. Other than that and some bad masking, it looks pretty good. I may need to try to fix it by using the plug-in first and then masking out the wire, but I'm having some problems with using footage in Blender that has been exported from Virtualdub. Once I can figure that out, I'll do another blog post to update you on what's happening.

Wire Removal Studying

I haven't gotten around to posting the rest about chroma keying yet, I think I'll do that later within the next few days, but I have done some studying and research on wire removal. I'm trying to figure out how to do it a couple ways and give options to programs like I did with the chroma key, but I think I'll probably mainly stick to blender since I've had pretty good quality results. I should probably animate something with wires as well instead of using still images to see if it really works too. I'm not sure how I'll share this yet, maybe as a video tutorial but I still need to get a time to record. Now onto a couple more tests.