Generating High Dynamic Range Radiance Maps from a Single Image

We present a method of generating high dynamic range (HDR) radiance maps from a single low dynamic range (LDR) image and its camera response function (CRF). The method first models and estimates the inverse CRF; then multiplies the inverse CRF by a weighting function to make it smooth near the maximum and minimum pixel values; finally conducts the smooth inverse CRF on the input LDR image to generate HDR image. In the method, the inverse CRF is estimated using one single LDR image and an empirical model of CRF, based on measured RGB distributions at color edges. Unlike most existing methods, the proposed method expands image from both high and low luminance region. Thus, the algorithm can avoid the artifacts and detail loss in dark area which results from extending image only from bright region. Extensive experimental results show that the approach induces less contrast distortion and produces high visual quality HDR image.