Full Body Pose Estimation for Sports Analysis - Pose Correction

Full Body Pose Estimation for Sports Analysis on NVIDIA ®Jetson™
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Camera Abstraction
Camera Calibration AprilTag Camera Calibration Chessboard Camera Calibration 3D Pose Estimation Pose Representation Skeleton Calibration Temporal Filter Kinematic Fitting Pose Optimization Pose Alignment Pose Correction Performance
Introduction Required Hardware How to Get the Code How to Install the Library How to Use the Library
Getting Started
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Introduction

The pose correction module is intended to map the trainer and traineeT sequences to a 3D space when needed and after that, compare them to obtain the differences. Additionally, it generates the corrections and displays them in a 3D GUI for the user to explore them interactively.

Pose correction module location in general workflow

How it Works

The different steps involved in this module are shown in the next flow diagram:

Flow diagram of the correction process.

Next we will get deeper into each of the submodules.

3D Representation Generation

In order to provide the movement correction it is required that this one is represented in 3 dimensions to ensure an accurate feedback. If the inputs are in 2D it is impossible to give a recommendation related to forward or backward movements due to the lack of depth of the image. Here we will use the front and side auxiliar views prepared in the alignment preprocessing in order to generate the 3D representation. As seen in the next image what we do is to map all the X and Y positions of the front views to the X a Z axes of the 3D space and then the X positions of the side views to the Y axis of the 3D space.

Mapping process from 2D to 3D space

Movement Differences Computing

Once we have the trainer and traineeT sequences in 3D space, we proceed to compute the differences between them in each frame. At this point, both sequences are temporally aligned, therefore each frame from the trainee sequence has its corresponding frame in the traineeT sequence. The differences between movements are computed by a common subtraction in each of the joints and also in each of the axes since we have to provide feedback in the three directions.