CGV Colloquium – Thursday July 16th

You are cordially invited to attend our next Computer Graphics and Visualization (CGV) Colloquium, which will be held on Thursday July 16, 2015, 15.45-17.20, in the Vassiliadis zaal (HB10.230). The program this month features the following speakers:

  • Panchamy Krishnan
    • Title – Supervised learning for measuring hip joint distance in digital X-ray images
    • Abstract – Osteoarthritis is a degenerative joint disease which is hard to measure objectively as the diagnosis differs from surgeon to surgeon.  Hip X-rays are used to diagnose this disease by measuring several characteristic features of the image, mainly the joint distance between the femoral head and acetabular cup.  Joint distance reduction is a clear sign of OA (it is a symptom of cartilage disappearance). This metric involves segmentation of the femur and acetabulum in x-rays, a challenging task because of contrast variations as well as external factors like anatomical and pose-variation. A multi-scale approach based on Machine Learning is proposed here providing a robust segmentation by detecting landmarks along the edges of the bone. The labelled landmarks are then used to determine the joint distance in several locations along the hip joint. The learning is supervised using manually annotated landmarks. The impact of landmark selection is studied in detail in this paper. The landmark detection is further refined using Active Shape Model (ASM) and gradient profiling.
  • Bas Dado
    • Title Compression of voxelized scenes using colored DAGs
    • Abstract – Voxels are great alternative for triangle-meshes. No texture and bump-mapping techniques are necessary to capture fine details, and rendering by means of raycasting is relatively cheap. However, a big dowside of voxels is the large memory footprint, even when a Sparse Voxel Octree (SVO) is used. Directional Acyclic Graphs can be used to reduce this problem but don’t allow for storing materials. We present a technique, based on the DAG compression, to efficiently store the voxel data. The presented technique is smaller than a standard SVO for all tested scenes in high resolution.
  • Kevin Allain
    • Title – Enhancing document triage process using multi layer visualization tool
    • Abstract The European Patent Office is an international organisation that is charged with granting patents for applications sent to their offices. To do so, the examiners have to verify if the claims of the application are indeed new or not, and thus perform a state of the art review. The tools currently used at the EPO return a list of patents that might match the keywords entered by the examiner, but it provides a very poor visualization of the results and document triage is a very cumbersome process. We work on a visualization of all the results from a search query to increase the document triage process, by showing data of all the results at once, offering several levels of details for the examiner to determine the patents that might not be relevant.

As a reminder, all CGV MSc students (both seminar and thesis project) are expected to attend our monthly colloquium series. All other interested colleagues are more than welcome, so feel free to disseminate this announcement.