Efficient Banding-Alleviating Inverse Tone Mapping for High Dynamic Range Video

In recent years, there has been an exponential growth in the number of devices that offer High Dynamic Range (HDR) viewing experience. An efficient and popular approach to constructing an HDR image from a standard dynamic range (SDR) image is to use "inverse tone mapping (iTM)." However, it can create or amplify visual artifacts such as banding/false contouring in the resulting HDR images. To address this, we propose a novel method to efficiently construct iTM to reduce banding in the highlight regions of HDR images. Our proposed approach uses a given iTM curve to estimate the banding-risk in each luminance range, based on the input SDR image properties. Then, the risk measure is used to adjust the local slope of the iTM to avoid banding in the resulting HDR images. Experimental results exhibit that our proposed method is highly effective in reducing banding in the HDR images.