Evaluating Texture Compression Masking Effects using Objective Image Quality Assessment Metrics

Published

August 1, 2015

Author(s)

Wesley N. Griffin, Marc Olano

Abstract

Texture compression is widely used in real-time rendering to reduce storage and bandwidth requirements. Recent research in compression algorithms has explored both reduced fixed bit rate and variable bit rate algorithms. The results are evaluated at the individual texture level using Mean Square Error, Peak Signal-to-Noise Ratio, or visual image inspection. We argue this is the wrong evaluation approach. Compression artifacts in individual textures are likely visually masked in final rendered images and this masking is not accounted for when evaluating individual textures. This masking comes from both geometric mapping of textures onto models and the effects of combining different textures on the same model such as diffuse, gloss and bump maps. We evaluate final rendered images using rigorous perceptual error metrics. Our method samples the space of viewpoints in a scene, renders the scene from each viewpoint using variations of compressed textures, and then compares each to a ground truth using uncompressed textures from the same viewpoint. We show that masking has a significant effect on final rendered image quality, masking effects and perceptual sensitivity to masking varies by the type of texture, graphics hardware compression algorithms are too conservative, and reduced bit rates are possible while maintaining final rendered image quality.

Citation

IEEE Transactions on Visualization and Computer Graphics

Volume

21

Issue

8

Pub Type

Journals

Download Paper

https://doi.org/10.1109/TVCG.2015.2429576

Keywords

MIP mapping, bump maps, texture compression, image quality assessment

Citation

Griffin, W. and Olano, M. (2015), Evaluating Texture Compression Masking Effects using Objective Image Quality Assessment Metrics, IEEE Transactions on Visualization and Computer Graphics, [online], https://doi.org/10.1109/TVCG.2015.2429576 (Accessed October 10, 2024)