tailieunhanh - Digital video quality vision models and metrics phần 2

. Hơn nữa, các thuộc tính kháng cáo hình ảnh được tích hợp trong PDM trong các hình thức sắc nét và colorfulness xếp hạng xuất phát từ video. Dữ liệu bổ sung từ các thí nghiệm chủ quan được sử dụng trong từng trường hợp để đánh giá về hiệu suất dự đoán. | INTRODUCTION Chapter 6 investigates a number of extensions of the perceptual distortion metric. These include modifications of the PDM for the prediction of perceived blocking distortions and for the support of object segmentation. Furthermore attributes of image appeal are integrated in the PDM in the form of sharpness and colorfulness ratings derived from the video. Additional data from subjective experiments are used in each case for the evaluation of prediction performance. Finally Chapter 7 concludes the book with an outlook on promising developments in the field of video quality assessment. 2 Vision Seeing is believing. English proverb Vision is the most essential of our senses 80-90 of all neurons in the human brain are estimated to be involved in visual perception Young 1991 . This is already an indication of the enormous complexity of the human visual system. The discussions in this chapter are necessarily limited in scope and focus mostly on aspects relevant to image and video processing. For a more detailed overview of vision the reader is referred to the abundant literature . the excellent book by Wandell 1995 . The human visual system can be subdivided into two major components the eyes which capture light and convert it into signals that can be understood by the nervous system and the visual pathways in the brain along which these signals are transmitted and processed. This chapter discusses the anatomy and physiology of these components as well as a number of phenomena of visual perception that are of particular relevance to the models and metrics discussed in this book. EYE Physical Principles From an optical point of view the eye is the equivalent of a photographic camera. It comprises a system of lenses and a variable aperture to focus Digital Video Quality - Vision Models and Metrics Stefan Winkler 2005 John Wiley Sons Ltd ISBN 0-470-02404-6 6 VISION images on the light-sensitive retina. This section summarizes the basics of the .