August 18, 2020

Adding 3D Objects to Video Footage

For this post, I’m going to give you an overview of how I added a wall of boxes into some video footage of my garage. To get started, you’ll need some footage that you want to add elements too. I shot my scene handheld which makes tracking a bit more difficult. To keep things simple, you can use a tripod and add in camera shake after everything is composed. If you do want to use a handheld shot, try and add some high contrast tracking points. These can be taped down markers or simply objects in a scene that stands out from the background.

Tracking the Footage

In Blender, go to the Motion Tracking layout and open your image. Go to the Toolbar Tab Track / Clip and click Set Scene Frame. This matches your blender timeline to the video clip.

Now to add the tracking points go to Markers Tab, choose Detect Features to automatically find points, or manually pick your points by choosing Add and click on what you want to be a marker in the footage. Try to add 10 or more markers. You can always delete the ones that don’t solve cleanly. Once the markers are set you can track those points by clicking the track forward button on the timeline.

Solving the track points

In the Solve tab, toggle on Keyframes so that Blender chooses the keyframes for you and the click the Solve Camera Motion button. Once the solve is done you’ll see the Solve Error range in the top right of your viewport. Try and get the error under 0.5 by deleting any tracking points that drift or go off target. You can also look at the waveform and select and delete and points that don’t fit the main motion path.

Once you are happy with the solve error. Go to The Scene Setup and click Set as Background. This aligns your video footage with your camera.

Defining the scenes axis

With everything tracked, the video footage and camera movements match but Blender doesn’t know what way is up. To align the axis of the scene to the footage, go to the Orientation tab, choose 3 points on a flat surface, and choose either wall or floor. Obviously pick the option that fits your scene. For my footage I chose Floor. Next, check your 3D viewport and see if things align right. If it’s giving you trouble, try choosing different tracking points and reapply the Orientation.

Modeling the scene

Now that the technical work is out of the way, it’s time to start modeling things. For my scene i’m adding boxes inside the garage so we will need to model anything that will be between our 3D props and the camera. That means the walls and garage door. After that you can add in your props.

Lighting

A big part of making your 3D objects fit the scene is to make sure your lighting matches. How you set up your lights all depends on your footage. Do some side by side tests with your basic geometry and compare it to your footage until you have something close. Pay close attention to how defined the shadows are.

Getting ready to render

The last part before we render it to hide the rough geometry while still keeping that cast shadows. To do this select your geometry, go to Object Properties, Visibility tab, and toggle on Shadow Catcher.

Render it

Now render out your scene and see how it all went! If you want to see you can also render out the scene without the footage and composite it in another program like after effects but that’s for another post.

July 17, 2020

Back Anatomy Studies

Whenever I take on a new project I can’t help but find my self running up against a wall of my understanding of something; whether it’s mechanics, concepts, or anatomy. One such project required me to create a detailed drawing of someone back, and rather than just finding a single point of reference to get me through that project, I wanted to really understand how the back muscles worked. So, here are some of my initial studies.

These aren’t anything too sophisticated, but it was enough surface-level understanding to give me confidence in my work.

April 12, 2020

Hard Surface Modeling

I'm working on a course by Creative Shrimp on hard surface modeling in Blender 3D. Here is a look at the progress.

This is the beginning where I am blocking out the basic shapes.

Once everything is blocked out, I worked on refining the each part, one piece at a time.

February 16, 2020

Expression Fun

I'm working on a project and created this little test to figure out my Java Script Expressions. Here is a basic overview of how this is built.

The large pulsing circles are precomposed animations that are reused for each of the 3 points. I've named these ORB_Comps. The Position variable has the following expression to create the jittery movement:

wiggle(2,10);

The connecting lines are Beam effects with endpoints defined with this expression:

Start Point = thisComp.layer("ORB_Comp 01").transform.position

End Point = thisComp.layer("ORB_Comp 02").transform.position

ORB_Comp ## defines the endpoints and moves the position of the Beam with the ORB_Comps

The smaller circles that travel along the Beams were a little trickier because it had to follow the beam which was connected by the orbs with a wiggle parameter. So the endpoints can't simply be defined by a fixed number. I ended up creating a Null object with a slider that ranged from 0 to 100, created some keyframes moving the slider from 0 to 100, easy eased them, and added this expression to loop that movement:

loopOut("pingpong")

Along with the slider I could then add the following expression to the small Pulsing Point:

s = thisComp.layer("SliderNull").effect("Slider Control")("Slider");
A = thisComp.layer("ORB_Comp 01").transform.position;
B = thisComp.layer("ORB_Comp 02").transform.position;
linear(s,0,100,A,B)

The expression linear(t, tMin, tMax, value1, value2). This takes the slider, 's', sets the min and max value of 's', in this case 0 to 100, and then changes the value from value1 to value2.

With these all combined together, it creates a set up that is independent of fixed positions and I can animate and move around the endpoints with all the connecting beams and pulse effects follow it perfectly.

July 24, 2019

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GUI Design

July 23, 2019

Spinner

July 22, 2019

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April 30, 2016

Walker

April 27, 2016

Drone

Still having a lot of fun with modeling. I've been learning a bit more about lighting. I found that I could make a material glow by using Indirect Lighting and increasing the Bounce.

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Contact me at asher@mindsize.us