Abdallah M H, Marble A E, Charayaphan C
Department of Electrical Engineering, Technical University of Nova Scotia, Halifax, Canada.
Med Biol Eng Comput. 1993 Sep;31(5):509-15. doi: 10.1007/BF02441987.
Presented in this paper is a simulation algorithm for the optimisation of camera position with respect to the signer, to have a full and reliable interpretation of the American Sign Language. The simulation includes a three-dimensional world point into two-dimensional image point transformation algorithm, the effect of the depth information loss and a sign projection correction test. It is concluded that the viewing camera should be positioned at any point in a specified area subtended by a solid angle of 30 degrees, where the centre of the area is located at 45 degrees in the azimuth and 45 degrees in elevation relative to the signer. The theory and the technique are tested with regard to the efficiency of interpreting American Sign Language (ASL) by two adult signers. One of the signers had been using ASL on a regular basis since infancy, and the second signer had signed for the past five years. It is demonstrated that positioning the camera anywhere in the specified area provides a 96 per cent correct interpretation of the 36 signs tested. The results also provide a preliminary indication that signer variability may not present a major problem in interpretation, and that a computer vision system which captures the optimum depth information can distinguish between signs which, to the naked eye, appear to have similar characteristics.
本文提出了一种模拟算法，用于优化摄像头相对于手语者的位置，以便对美国手语进行全面且可靠的解读。该模拟包括三维世界点到二维图像点的变换算法、深度信息丢失的影响以及手语投影校正测试。得出的结论是，观察摄像头应放置在一个特定区域内的任意点上，该区域由一个30度立体角所张成，区域中心相对于手语者在方位角45度和仰角45度处。针对两名成年手语者解读美国手语（ASL）的效率，对该理论和技术进行了测试。其中一名手语者从婴儿期就开始经常使用ASL，另一名手语者在过去五年中一直使用手语。结果表明，将摄像头放置在指定区域的任何位置，对36个测试手语的解读正确率达到96%。结果还初步表明，手语者的个体差异在解读中可能不是一个主要问题，并且能够捕捉最佳深度信息的计算机视觉系统可以区分那些肉眼看起来具有相似特征的手语。
