• Image-2-Lixel: New Method For Accurate Human Pose and Mesh Estimation

    In a novel paper, researchers from the Seoul National University in Korea have proposed an accurate method for 3D human pose and mesh estimation from a single image.

    Typically human pose estimation methods work by learning a mapping between the input pixels and the parameters of a human mesh model. In contrast, the new method works by predicting a lixel-based 1D heatmap before predicting the final output pose and mesh. The so-called “lixel” is in fact short for “line + pixel” and the idea behind the introduction of lixels is the preservation of spatial relationships in the input image. According to researchers, the produced high-resolution 1D heatmaps allow for precise dense mesh vertex localization.


    Diagram of the overall framework for human pose and mesh estimation,

    They propose an overall pipeline for both human 3D pose and mesh estimation, consisting of two deep neural network models: PoseNet (for human pose estimation) and MeshNet for regressing 3D human meshes. The diagram below shows the network architecture that researchers use for estimating the lixel-based 1D heatmaps.


    The architecture of the 1D heatmap estimation network.

    The PoseNet model estimates three lixel-based 1D heatmaps of all human joints given the input image. The MeshNet network takes as input the image feature from PostNet and a 3D Gaussian heatmap in order to produce the final 3D human mesh.

    Researchers conducted experiments on several benchmark datasets: Human3.6M, 3DPW, FreiHAND, MSCOCO, MuCo-3DHP. Results showed that the method achieves state-of-the-art performance.

    More details about the method can be read in the paper published on arxiv. The implementation was open-sourced and it is available on Github.