Blender Motion Tracking - Room Transformation!

[Applause] so I wanted to do a series showing how to go from a green screen to a finished scene in blender but I got to break it up this one's motion tracking motion tracking is one of the keys to transforming a small set into a large one or putting your characters into entire digital worlds it's this incredibly powerful tool for low-budget indie filmmakers since it's one of the best ways to merge real-life with your digital creations the the computer stuff the blender tracker is crazy powerful but as many have noted it can be a little intimidating to get into so let's just blast through first pass so you can wrap your head around it open up a motion tracking interface and load in your footage make sure the scene framerate matches the framerate of your footage hit set scene frames to make the scene match the clip length and prefetched load in the RAM this makes it all more responsive there's lots of motion models but for big shifts like this perspective makes sense I'm gonna go to the middle of the clip since it's more likely points visible there will also be visible at the beginning in the end and I'm gonna go through and control click on points with identifiable patterns like it's a moss or paint or bright pieces of gravel hit a to select them all then track them in a direction great now go back to the middle and track the other way a couple didn't make it but we only need eight good ones for a track so I'm just gonna delete him jump on over to this all panel I'll let blender pick the key frames and I'll let it refine the focal length and the K twins hit solve one point zero eight pixel err that's actually pretty good I can turn on the info check box and see what the average errors are ideally less than one five delete it one point one delete it resolved it point two pixels that's that's real good yeah let's use that I'm gonna set it as the background and set up the tracking scene that drops it all into the viewport but it doesn't know which way is up select the point make it the origin that'll be the center of the scene select three other points and make them the floor great put your monkey in there and go tell your mom because this is very exciting but it's rarely that easy I mean it can be it is that only took a couple minutes but it was a pretty optimal situation wanna know a secret though whatever you can whenever you shooting try to make it an optimal situation there'll be times if you're doing it professionally when a client might give you footage in you just have to work with what you got the other half of the time though they'll bring you on set specifically to make sure you're getting what you need so try to keep the shot steady with minimal motion blur you can keep the aperture small yova deep depth of field with a lot more points in focus make sure there's stuff in the shot you can track if you're not sure you can put little pieces of tape up but little like rocks and pinecones can work too ideally stuff you don't have to paint out and post because that makes your life harder it also helps to know how this all works like say you had a bunch of lights on sticks in your yard you walk around filming them some dots are closer and appear to move faster than lights in the background that's that's parallax you give it to a computer and say a computer I bet you can't tell me the cameras movement just by looking at these points of light idiot and the computer goes why are you being mean to me I'm a computer this is easy there's only one camera movement that could explain the changing of these 2d points relative to each other here you go that's why you want points in different areas if they're all in one wall for example the computer has trouble knowing if say the cameras just rotating around or it's actually moving around because the pattern of dots stays the same so let's try a more complicated example so I film this with Caitlin and we live out in the woods but I want to make a bunch of sci-fi films and sci-fi happens in the big city so perhaps this is a problem we can fix with motion tracking I sure hope so so we couldn't do this the same as the other one take our tracking points and babysit them and clean them in all that and there's a lot of great tutorials out they've had to do that I've linked some of them below but I want the computer to do the work so new motion tracking layout set the frame rate load in the footage set scene frames prefetch I'm gonna go with a location motion model this time since most points we're tracking are just gonna be points on the wall without too much perspective shift and now the good stuff Auto detect features I'm gonna lower the threshold to like 0.2 zero one and the distance to eighty whoa then we're gonna start tracking forward and look at him go but as the camera moves some trackers are disappearing and we're seeing new empty space so I'm gonna hit escape to stop detect more features hit a to select all the previous ones and keep going just brute-force in it whenever they start to disappear I'm gonna add some more some of these are going nuts let them have their fun before you know it you're done look at this wonderful mess great we have data let's clean it a bit you slide open the graph you'll see some lines are going haywire if you click them you can see the corresponding point yeah that's that's no good you can click on those and delete them but blender can also do that automatically jump to the solve panel and click filter tracks I'm gonna slide this number up until only the most extreme little guys are left to lead them grabs a lot cleaner now you know so eyeball it there's a few on her those obviously aren't good there's also places where a foreground edge will intersect a background edge these move as you change perspectives so that's that's no good either great let's try to solve it this time we're not using Auto key framing we'll set our own pick two frames that have fairly different points of view but contain eight or more of the same tracking points something that demonstrates the parallax if the track solves taking a really long time are you randomly getting these huge solve errors and banging your head against the wall a lot of times tweaking the key frames will fix that we find the focal length indicate wins and lets go few seconds later 1.3 pixel err not bad now the blender has a solution in mind we can compare it to the tracked points let's just click clean tracks and if we're lucky we can put in a reprojection air of 1 this will select any points that if more than a pixel away from where blender would expect them to be a lot of times they do in something a little bit weird in this case it's selecting more points than it probably should so I'm gonna put in 3 pixels instead delete the selected points and solve it again hey listen a pixel that could work but let's style it in cleaning with a reprojection error of 1 andrey solve hey listen have a pixel that's great excellent click set as background and setup the tracking scene and it's ready to go but remember last time we selected the points on the ground to orient things this one doesn't really have that but we can add some real easy go to a place with a good view of the floor and control click on a few trackable zones now we have a good camera solve you only need to track a few frames to snag the position Reese all've and look your points appear this is really handy for lots of stuff especially reconstructing the environment so select your three points and click floor to make a floor then set your origin to be the center of a scene if you can find a point that's along the same axis as the origin select it and hit that axis someone will get everything straightened out look at that oh jeez head into the layout workspace we've got our animated camera open the overlay panel and turn on motion tracking now we can see our points this is a tracking tutorial not a modelling tutorial but let's do some stuff I'm gonna start modeling a wall using the tracking points as a guide mostly just extruding stuff out if you want more tips on modeling environments you can check out the modeling buildings tutorial linked below I'm also gonna model a rough interior matching the layout of the back wall and I'm gonna put our footage on it so create a new material and give it an emissive surface and let's make the base color and image texture load in your footage crank up the frames hit auto refresh and we're gonna set the vector to window so now the footage is gonna fill a whole camera view it's a bit weird that it repeats so change it to clip there we go if you line things up right and made the geometry of the wall match the points you can now tab into edit mode and just hit Katie using the knife tool to trace the window delete that face and hey look it's a window it actually kind of lines up that's that's cool I'm gonna import an image and put it way in the distance sky isn't tall enough so in edit mode I'm gonna add an edge loop and just stretch that top bit up yeah that's cool next I'll block in the apartment details a little bit I'm gonna create a new material with an image texture and load in a good wall image next I'll select all the faces and hit u cube projection if I open up a UV panel load in that same image I can select faces and drag around the ones that don't work until I like it where the draw all the rest of the owl here but honestly this part was a slippery slope to begin with so there you go it's really fun to be able to scroll around and see it all in real time and Evie we could spend a lot more time on it but we'd put our house in the woods into the big city also goes to show you only need a back corner of a set everything in front you can add digitally without green screens or anything although speedy in green screens I'm working on that tutorial next so stuffs crazy over on the patreon started a few weeks ago I've got breakdowns and I've got tutorials and model and stuff from photos and 3d out lots of 3d assets and behind the scenes hopefully a lot of bang for your buck and you get to help me finish some films and get these tutorials made huge thanks to everyone who jumped on board already you've made some some intense weeks significantly better so I'll see you soon

Channel: IanHubert

Views: 1,602,836

Rating: 4.9823236 out of 5

Keywords:

Id: lY8Ol2n4o4A

Length: 7min 57sec (477 seconds)

Published: Tue Mar 24 2020

Reddit Comments

[u/Ross_Kun]

That was amazing... that’s all I can say about that

[u/northernlightsorbust]

3D stuff has always been outside of my realm of knowledge. This guy seems like a great way to learn, like Andrew Kramer with After Effects but for Blender.

Huge props to him for not being dry in a tutorial. Especially loved the bit 4:00 in— “Look at this wonderful mess! Great, we have data.”

[u/[deleted]]

well, you should watch all his videos, even if you don't use Blender. they are pretty informative and a great load of fun.

[u/T-Conner]

omg they have to bring Ian on VFX artists react

[u/badken]

This shit is PFM. Cool examples!

[u/RustedBlade7]

Great video, Ty :)

[u/benshivers11]

He sounds like wren