Noise reduction and adaptive contrast enhancement for local tone mapping

In this paper, we propose a noise reduction method and an adaptive contrast enhancement for local tone mapping (TM). The proposed local TM algorithm compresses the luminance of high dynamic range (HDR) image and decomposes the compressed luminance of HDR image into multi-scale subbands using the discrete wavelet transform. For noise reduction, the decomposed images are filtered using a bilateral filter and soft-thresholding. And then, the dynamic ranges of the filtered subbands are enhanced by considering local contrast using the modified luminance compression function. Finally, the color of the tone-mapped image is reproduced using an adaptive saturation control parameter. We generate the tone-mapped image using the proposed local TM. Computer simulation with noisy HDR images shows the effectiveness of the proposed local TM algorithm in terms of visual quality as well as the local contrast. It can be used in various displays with noise reduction and contrast enhancement.