From the Android NDK example "bitmap-plasma": We're going to perform computations for every pixel of the target bitmap. floating-point operations are very slow on ARMv5, and not too bad on ARMv7 with the exception of trigonometric functions. For better performance on all platforms, we're going to use fixed-point arithmetic and all kinds of tricks I… Continue reading [Note] floating-point/fixed-point operations versus OpenGL
Month: June 2011
Augmented Reality Glasses
AR see-through glasses. Built-in 1080p cam. Compass. Earphones. 4999 USD. Vuzix STAR 1200 Augmented Reality System.
Review: "Parallel Tracking and Mapping on a Camera Phone"
Based on the PTAM Project (here PTAM-d for PTAM running on a desktop computer), which originally runs on a computer, Klein and Murray adapted the code to run on an iPhone 3G (here PTAM-m for PTAM running on mobile device such as smartphone). Of course everything need to become more light-weighted so that it can… Continue reading Review: "Parallel Tracking and Mapping on a Camera Phone"
Shi-Thomasi Corners
Shi-Thomasi is a corner detection algorithm improved from Harris' corner detector. The improvement is the way how a certain region within the image is scored (and thus treated as corner or not). Where the Harris-corner detector determines the score with the eigenvalues and of two regions (the second region is a shifted version of the… Continue reading Shi-Thomasi Corners
Review: "Parallel Tracking and Mapping for Small AR Workspaces"
The paper describes the methods and techniques used in the PTAM project. Usually AR systems only work probably when the running system has a certain knowledge of the surrounding area. This knowledge could pre-acquired information of an object or a know marker (a marker could for example a monochrome pattern that is put, like a… Continue reading Review: "Parallel Tracking and Mapping for Small AR Workspaces"