How was the film Alice in Wonderland filmed? The characters in it are too real. What technology is it?

Implementing other roles outside the digital environment

We know that actors have to interact with CG characters, so we let the staff wear green jumpsuits on the set. In fact, all CG characters should have been created from the beginning, but they were added with real shots later. We filmed a lot of minor characters, and these characters had to interact with the main characters. So in the movie, you can see the people behind the Queen of Hearts and Mr. Mad Hatter and the people who interact with them. In fact, these people were not on the scene when shooting, which increased our challenge. We need to synthesize different materials, and we can't use motion control.

The Formation of 3D and Stereo Effects

3D is an important part of movies. We knew from the beginning that this was a stereoscopic film, so we decided to shoot it with a stereoscopic camera, that is, the two cameras were divided into left and right eyes. Later, for several reasons, we didn't shoot with a 3D camera. The main reason is that we have to do a lot of zooming, so we need to use a high-resolution camera. So far, there is no suitable 4K camera (such as Dalsa) to complete 3D shooting. So even if we set up a camera system, there are only two prototypes. If a movie is shot more and CG characters less, it is very suitable for stereo shooting. But because we started with a digital environment, we gradually added many other elements, so it's best to finish the three-dimensional effect later.

After we make this decision, we will get more 3D depth information when shooting. In addition, we need to understand the actors' position in the scene and their interaction. Especially for the interaction between actors and CG characters, we can put 3D characters in the right position through depth information. We put a lot of reference cameras on the set, and Sony950' s are everywhere in the scene, which helps to triangulate and determine the position of actors.

If you create a three-dimensional effect later, there are generally two methods. The first technology is rotary automation, which is the most commonly used method. The motion trajectory of the camera is obtained from the motion matching of the material shot by the green screen, and then imported into the model of the character to simulate the motion of the camera frame by frame, and then the camera information is re-projected on the model, and then the camera of the other eye is applied to the scene. The second is a technique similar to displacement mapping, which only modifies the edge of the character at key frames. For example, an arm, you can key it and then replace it. Just don't use depth information, but use vision to define it. If you don't get depth information from the studio, it's best to use this technology.

The fit between the real shot character and CG material

We knew from the beginning that we should combine the real shot character with CG material. And our biggest challenge is to bridge the gap between these two materials, Tim? Burton doesn't want to see completely real characters moving in the virtual environment. Characters should be integrated into the environment, better integrated into the environment. Tim hopes that these real characters can better integrate into this exaggerated world.