• Web

    Fixing DB problems in Joomla

    Sometimes, this site goes down, and the following homepage appears: The jos_session gets corrupted, a frequent issue with Joomla 1.5.x installations. Luckily, fixing this issue is quite simple, just log into the phpMyAdmin site (usually at the following address: http://www.mywebsite.com/phpMyAdmin) and open the joomla database Locate the jos_session table, then…

  • Software

    Fixing Here Maps in Windows Phone 8

    After the map updates on mid-May, both the HERE Maps and Drive apps for Windows Phone 8 stopped working, even worse, launching them made the phone reboot. The obvious fix would be an hard reset of the phone, but that would mean a lot of work, backing up everything. Here…

  • Video

    Background subtraction: ViBe

    The ViBe algorithm In the paper “ViBe: A universal background subtraction algorithm for video sequences“, Olivier Barnich and Marc Van Droogenbroeck introduce several innovative mechanisms for motion detection: Pixel model and classification process Let’s denote by v(x) the value in a given Euclidean color space taken by the pixel located…

  • Video

    Background subtraction: neural and neuro-fuzzy methods

    Performance map Adaptive SOM of Maddalena and Petrosino (2008) paper link {youtube}o7VdgyoxPgA{/youtube}  Detection of moving objects in video streams is the first relevant step of information extraction in many computer vision applications. Aside from the intrinsic usefulness of being able to segment video streams into moving and background components, detecting…

  • Video

    Background subtraction: methods based on eigen features

    Performance map Eigenbackground / SL-PCA of Oliver et al (2000) paper link {youtube}4c1lLY3ta08{/youtube} We describe a real-time computer vision and machine learning system for modeling and recognizing human behaviors in a visual surveillance task [1]. The system is particularly concerned with detecting when interactions between people occur and classifying the…

  • Video

    Background subtraction: non-parametric methods

    Performance map Pixel-Based Adaptive Segmenter (PBAS) of Hofmann et al (2012) paper link {youtube}DjCLUQg4dow{/youtube}  In this paper we present a novel method for foreground segmentation. Our proposed approach follows a non-parametric background modeling paradigm, thus the background is modeled by a history of recently observed pixel values. The foreground decision…