A new kind of HDR image tone compression algorithm

In order to display and output HDR(High Dynamic Range) images on the conventional equipments, this thesis proposed a new kind of HDR image tone compression algorithm based on local environmental luminance factor. The workflow of new algorithm is based on the latest image color appearance model iCAM06, as shown in Fig.1. The new algorithm decomposed the original HDR image into the base layer image and detail layer image by the edge-preserving filter method. Then the tone compression function based on the environmental luminance factor was used for the tone range compression of HDR image. And this is the innovation point of the thesis. Lastly the thesis used the image quality evaluation model based on the dynamic range independence to evaluate the reproduction accuracy performance of new HDR tone compression algorithm. The distortion probability graph derived from the original HDR image and compressed image shows that the tone range compression performance of the new algorithm is better than the other algorithm. In addition, the new tone compression function has a low complexity and high execution efficiency.