摘要
在数字化时代,图像亮度动态范围获取和显示都离不开转换函数和采样比特位深.当今,虽然图像系统中亮度获取和显示的能力已经得到显著提升,若转换函数选取不当,在既定比特位深下,仍会出现亮度阶梯现象,造成图像质量下降.本文以人眼对比灵敏度为衡量标准,讨论现有高动态范围内容制作标准中,不同转换函数、不同量化位深对图像质量的影响.通过计算,与Barten视敏度模型对比,表明使用12比特位深的PQ不会产生采样量化带来的亮度阶梯现象;在显示最高亮度为200 cd/m^2时,使用12位比特位深的修改后的Gamma2.6与PQ表现相似.
In the digital age,the acquisition and display of the image brightness dynamic range are inseparable from the transfer function and the sampling bit depth.Nowadays,although the ability to obtain and display brightness in image systems has been significantly improved,if the transfer function is not properly selected,at a given bit depth,there will still be a brightness staircase phenomenon,resulting in a decline in image quality.This article takes the contrast sensitivity of human eyes as the measurement standard and discusses the impact of different transfer functions and different quantization bit depths on the image quality in the existing high dynamic range content production standards.Through calculation,compared with the Barten visual acuity model,it is shown that the use of 12-bit depth PQ will not produce the brightness staircase phenomenon caused by sampling quantization;when the maximum brightness of the display is 200cd/m2,the modified Gamma2.6 with 12-bit bit depth behaves similarly to PQ.
作者
顾晓娟
常乐
Gu Xiaojuan;Chang Le(Film and TV Technology Department,Beijing Film Academy)
出处
《现代电影技术》
2020年第6期7-10,共4页
Advanced Motion Picture Technology
基金
《电影数字水印和新型显示格式关键技术研究与示范》项目,项目编号:2018YFB1404004
北京电影学院校级项目《基于LED电影屏幕的放映技术指标推荐方案研究》,项目编号:XZ201802。
关键词
转换函数
量化比特位深
对比敏感度
Transfer function
Quantization bit depth
Contrast sensitivity
