tailieunhanh - Báo cáo hóa học: " Research Article Flicker Compensation for Archived Film Sequences Using a Segmentation-Based Nonlinear Model"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Flicker Compensation for Archived Film Sequences Using a Segmentation-Based Nonlinear Model | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 347495 16 pages doi 2008 347495 Research Article Flicker Compensation for Archived Film Sequences Using a Segmentation-Based Nonlinear Model Guillaume Forbin and Theodore Vlachos Centre for Vision Speech and Signal Processing University of Surrey GU2 7XH Guildford Surrey UK Correspondence should be addressed to Guillaume Forbin Received 28 September 2007 Accepted 23 May 2008 Recommended by Bernard Besserer A new approach for the compensation of temporal brightness variations commonly referred to as flicker in archived film sequences is presented. The proposed method uses fundamental principles of photographic image registration to provide adaptation to temporal and spatial variations of picture brightness. The main novelty of this work is the use of spatial segmentation to identify regions of homogeneous brightness for which reliable estimation of flicker parameters can be obtained. Additionally our scheme incorporates an efficient mechanism for the compensation of long duration film sequences while it addresses problems arising from varying scene motion and illumination using a novel motion-compensated grey-level tracing approach. We present experimental evidence which suggests that our method offers high levels of performance and compares favourably with competing state-of-the-art techniques. Copyright 2008 G. Forbin and T. Vlachos. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION Flicker refers to random temporal fluctuations in image intensity and is one of the most commonly encountered artefacts in archived film. Inconsistent film exposure at the image acquisition stage is its main contributing cause. Other causes may include printing errors in film .