内存带宽通常是计算机图形系统的瓶颈,文中总结了用于降低图形系统带宽开销的常见机制,在纹理压缩算法S3TC基础上,提出场景前颜色缓冲区压缩方法——YCoCg-R CBC.该方法定义了2种颜色缓冲区压缩数据格式,将像素转换到YCoCg-R颜色空间,对亮度和色度数据分别处理,并使亮度数据具有较高精度.实验结果表明,YCoCg-R CBC 2种数据格式的平均PSNR值各为41.71 dB和47.24 dB,较S3TC算法分别提高了7.87 dB和13.40 dB;解压图像质量得到显著改善,已经很难观察到它们与原始图像的差异.
Memory bandwidth is often the bottleneck of computer graphics systems.Various methods used for reducing the bandwidth consumption are summarized in this paper.A pre-scene color buffer compression scheme,named YCoCg-R CBC,is proposed on the basis of the texture compression method S3TC.By the method,two data formats for color buffer compression are defined,and the pixels are transformed to YCoCg-R color space.Afterwards the luma data and chroma data are handled separately,with the luminance possessing higher accuracy.Experiment results show that the average PSNR scores of YCoCg-R CBC format I and format Ⅱ are 41.71 dB and 47.24 dB respectively,with an improvement of 7.87 dB and 13.40 dB in comparison with S3TC.The quality of the images decompressed is significantly improved,and as a result,the difference from the original ones is hardly perceived.