基于改进拉普拉斯金字塔的HDR图像色调映射算法

Tone Mapping Algorithm for High Dynamic Range Images Based on Improved Laplacian Pyramid

为进一步提升高动态范围图像在普通显示器上的呈现效果,提出了一种基于改进拉普拉斯金字塔的高动态范围图像色调映射算法。该算法将预处理后的图像分解为高频层和低频层,分别输入2个特征提取子网络,将2个包含不同特征的输出图像融合后再输入微调网络,最终得到感知效果优越的低动态范围图像。此外,该算法设计了自适应分组卷积模块以增强子网络提取局部和全局特征的能力。测试结果表明:与现有的先进算法相比,所提算法可以更好地压缩高动态范围图像的亮度,保留更多图像细节,拥有更加优越的客观质量指标和主观感知效果。

A tone mapping algorithm for high dynamic range(HDR)images based on the improved Laplacian pyramid is proposed to enhance the rendering effect of HDR images on ordinary displays.The algorithm decomposes the preprocessed image into high-frequency and low-frequency layers,which are then fed into two feature extraction subnetworks.The algorithm combines their output images having different features via a fine-tuning network and finally obtains a low dynamic range image with a superior perceptual effect.Furthermore,the algorithm designs an adaptive group convolution module to enhance the ability of the sub-network to extract local and global features.The test results show that,compared to the existing advanced algorithms,the proposed algorithm can compress the brightness of the HDR image better,retain more image details,and achieve superior objective quality and subjective perception.