Human Skeleton Model

SMPL model is a parametric model of the human body

• SIMP series method
  SMPL-LBS, SMPL-DQBS

• Disadvantages of the prior 3D mannequin
  does not skinned, after obtaining a 3D model of the human body, you need to add rig, also need to manually adjust the surface texture maps;
  not compatible with existing commercial software;
  not true, it is difficult to deal with all kinds of attitude

• About
  SIMP collected different postures real human grid, to establish the shape parameter (shape), posture parameters (pose) correspondence between the grid (mesh), the training out of this correspondence. LBS compared to traditional methods, a method which surface topography body posture image that simulates human muscle projections and recesses in the limb during exercise, the body surface can be avoided during the movement of the distortion can be accurately describe the morphology of muscle stretching and contraction movement of people.
  Note:
  LBS: Skinned A typical method commonly used in the industry

• Keywords animation

  • Vertex (mesh): animation model can be seen as a plurality of small triangles (quadrangle), each of which can be seen as a small triangle vertex. The more vertices, the finer the animation model.
  • Skeletal point: some of the joints of the human body, similar to the key points of the human body pose estimation. Each triple consists of a skeletal point as a parameter to control (Euler angles can be viewed, quaternions related concepts)
  • Skinned (Rig): establish relationships skeleton points and vertices. Each point will associated with skeletal many vertices, and each vertex weights is not the same. Through this relationship, it can be controlled by rotating the whole person motion vector control skeletal points.
  • Texture mapping: surface texture animated mannequins that these dress pants.
  • BlendShape: animated character movement control, there are two, one is said above, use Rig, there is a use BlendShape. For example: produce a smiley face and normal, then it can automatically generate both transition animation by BlendShape. In this way, compared to the use of Rig, you can not define the skeleton point, more convenient.
  • Skin: The model of transition from one posture to another posture, called the transformation matrix used skin matrix.

• Parameters
  β: height and weight ratio of the body, the head body 10 other than the parameters
  θ: 75 parameters of overall body posture and movement relative angle joints 24

  • Shape parameter

  • Posture parameter

• References
  another SIMP model [Keep it SMPL: Automatic Estimation of 3D Human Pose and Shape from a Single Image ] complete data
  SMPL basic model and resource use Download
  animation Glossary