Rotoscoping Tips in Blender

through the power of rotoscoping we can turn a shot like this into this hey i'm canon profit and in this tutorial we're going to break down some of the tools blender has for rotoscoping so that you can make some pretty awesome visual effects shots using blender so i'm going to jump into the masking section of the vfx tab in blender and here i have this footage of this strapping individual walking down the street i'm going to make a mask by pressing ctrl and left click mask around right here and i'll press alt c to close that mask you can see we have a straight point we can press v and change the handle type of that i like to use a line single and boom you've just made a mask how about that there's a lot of cool things we can do here i can press a to select everything can switch the direction of the mask i can also change the handle type the vector handle type is very useful for geometric shapes such as telephone poles or houses if i want to add a point just press control between two points and click and that'll add an additional point there i'm going to change everything back to a line single since that is my preferred method of masking and voila you can also scale the feather that green outline indicates that the mask will be feathered by that diameter and if i come up here to mask display i can see what my final matte is going to look like inside my comp you can view the color combined or also just the alpha so you can see what your black and white matte will be all right now let's get into the nitty-gritty let's hit record jump to a different frame and start adjusting that mask voila you're rotoscoping rotoscoping is just animating a mask so all the normal keys work in blender r to rotate g to grab a to select all and when rotoscoping it's important to jump every 10 or so frames i like to begin on the most important frame the one that has the most information and then work backwards from there jumping every 10 frames or so the more in betweens you do with your animated mask the more precise and clear your rotoscope will be now obviously this very simple mask isn't going to work for an organic shape such as someone's body so it's important to break it down into shapes that are easy to track so for this if we were to just do one mask all around my body here that shape would change way too much so it's important to break it up into different shapes so i've already done the work here i did a rotoscope of the head we can view what that looks like i did a rotoscope of the legs as one mask and each arm and then also the body and breaking it up into shapes like this you might think that's more work but it actually saves you time because you're having to change the mask less and you're able to worry about just one specific part of the body and this is kind of a pro tip for you as well if you were to work in a vfx studio this is how they would want you to work with complex shapes so that you have complete control over each section of your rotoscope so how do we use this info let's jump into the compositor i'm going to press shift a and add a mask node and just choose one of the masks we've created and if we control shift and click we can view that and drop in a scale node here for housekeeping purposes and there you go we can view our roto i'm going to shift d to duplicate that and i'm just going to start plugging in all the other masks i've created here we can add all of these together by using math nodes just duplicating those math nodes adding each mask together it doesn't really matter which order you do all this in just so long as you have all of your individual masks combined and if you want to clamp those values there so that it's just a pure black and white matte and that works alright so now you should have a completely rotoscoped black and white map which is great i'm going to control g to group all those so now i just have my clean little rotoscope node right there and i can always tab back into that and make changes if i need to now you're almost there from having a very usable rotoscope if you want to clean up those edges even more i like to use a dilate your road node and feather that a little bit all right now we're going to utilize the power of the set alpha node so i'm going to press shift a and drop in a set alpha node and this is really critical to having complete control over your rotoscope if i take the image into the image factor of that set alpha and the matte output into the alpha boom i've got my isolated object here and i can treat this as kind of a layer so i might do a little bit of edge cleanup here but now we have an isolated layer that we can do whatever we want we can transform it we can comp it in over top of our background footage here so i'm just going to easily comp that in by pressing shift a dropping in alpha over node i'm going to convert premultiply there and there just by throwing in a transform node you can see that i can make adjustments there and really set that layer just treating it as a as if it were just a video layer right inside so now we need to make a simple mask for the wall here and we don't need to rotoscope this because it's just a still image but we can do the exact same thing plug in our mask into a set alpha node and that allows us to comp that wall in over top of our layered footage there we can make adjustments to that wall scale it up scale it around move it around and blur it make it look like this was shot from a far distance with a long lens make this feel more like a spy shot which is pretty cool nice now we have something like this cool all right obviously uh if this were an actual vfx shot that i was doing for a movie or a show i'd want to integrate that original plate a little bit so just do some color correction there desat a little bit make sure i'm matching the values of my background plate so that later i can color correct it all together so that it feels like it's integrated now you could certainly stop there that's utilizing the power of rotoscoping but let's make good use of that perfectly good black and white mat we already did and do a little bit of light wrapping so i want a nice clean edge for my light wrapping so what i can do is just utilize this original map i'm going to give myself some space here because we really want this to happen before the compton wall so right at kind of this point of my comp i want to add the light wrap so i'm going to move all these down and here i have some space to work for my light wrap so i'm going to add in a mix node and take the matte output into the top factor of that mix node i'm going to duplicate that dilated road node and just hook up the original map and if i set that mix node to subtract and increase that dilate erode you can see now we have something that looks like we can use for some light wrapping nice edge there i'm going to just blur this a little bit so we have a cleaner light wrap bleeding effect and these are all adjustable i can tweak them however much i want that light to be wrapping around my subject i can just adjust that dilated road factor right there so now that mask is going to be used as a factor of a mixed node where i'm mixing my footage plate here with my background plate so i'm going to press shift a drop in a mix node and plug in my background plate into the bottom of that mixed node take my comp up to this point and to the top so now i'm mixing my footage my character with my background plate and take the factor of my dilate erode and put it into the factor of that mixed node and i'll set it to add and there you can see that background image is wrapping around the character like so i can turn this down by duplicating that mix node setting it to multiply and the bottom color to black and now with this factor slider i can adjust how much of that light wrapping we see which is pretty cool so now i have an easily customizable setup where i can adjust my light wrap all these little factors that you can tweak and that's pretty much it i'm gonna plug that back into the rest of my comp so there you go you could add in some camera shake or color correction at that point there's so much more you can do but this was definitely just kind of a broad overview of how you can do some rotoscoping inside of blender and really up your vfx shots hope this was useful this has been canon profit for cg cookie thanks for watching

Channel: CG Cookie

Views: 70,986

Rating: 4.9640827 out of 5

Keywords: blender, tutorial, blender tutorial, cg cookie, blender 2.8, blender how to, vfx, rotoscoping, kenan proffitt

Id: 1eQst8SAVRE

Length: 9min 49sec (589 seconds)

Published: Wed Aug 19 2020