Image quality evaluation for high dynamic range and wide color gamut applications using visual spatial processing of color differences

High dynamic range (HDR) and wide color gamut imagery has an established video ecosystem, spanning image capture to encoding and display. This drives the need for evaluating how image quality is affected by the multitudes of ecosystem parameters. The simplest quality metrics evaluate color differences on a pixel‐by‐pixel basis. In this article, we evaluate a series of these color difference metrics on four HDR and three standard dynamic range publicly available distortion databases consisting of natural images and subjective scores. We compare the performance of the well‐established CIE L*a*b* metrics (ΔE₀₀ , ΔE₉₄ ) alongside two HDR‐specific metrics (ΔE_Z [J_za_zb_z], ΔE_ITP [IC_TC_P]) and a spatial CIE L*a*b* extension (). We also present a novel spatial extension to ΔE_ITP derived by optimizing the opponent color contrast sensitivity functions. We observe that this advanced metric, , outperforms the other color difference metrics, and we quantify the improved performance with the steps of metric advancement.     

Optimization of Kiln Drying for Softwood through Simulation of Wood Stack Drying,Energy Use,and Wood Color Change

An integrated modeling system was developed to simulate the drying processing, energy use, and wood color change in kiln drying of softwood timber. The model has been applied for a temperature range from 50 to 70°C and an airspeed from 3 to 9 m/s. The model is based on theoretical analysis and contains components such as kiln configuration and practical operations. From the model simulation, optimized drying schedules for minimizing color change and energy use are recommended with dry bulb temperature of 60 to 70°C and wet bulb depression of 15 to 20°C.     

Optimization of Kiln Drying for Softwood through Simulation of Wood Stack Drying, Energy Use, and Wood Color Change

An integrated modeling system was developed to simulate the drying processing, energy use, and wood color change in kiln drying of softwood timber. The model has been applied for a temperature range from 50 to 70°C and an airspeed from 3 to 9 m/s. The model is based on theoretical analysis and contains components such as kiln configuration and practical operations. From the model simulation, optimized drying schedules for minimizing color change and energy use are recommended with dry bulb temperature of 60 to 70°C and wet bulb depression of 15 to 20°C.