I have a project for gesture recognition. I was wondering how can use C# or Java to program it? Is there any special library? Do I need programming or do I need a special device rather than a webcam?
Have you looked at OpenCV?
OpenCV (Open Source Computer Vision) is a library of programming functions for real time computer vision.
Example applications of the OpenCV library are Human-Computer Interaction (HCI); Object Identification, Segmentation and Recognition; Face Recognition; Gesture Recognition; Camera and Motion Tracking, Ego Motion, Motion Understanding; Structure From Motion (SFM); Stereo and Multi-Camera Calibration and Depth Computation; Mobile Robotics.