Spatially adaptive tone mapping for display of high dynamic range (HDR) images

摘要

Techniques are provided for spatially adaptive tone mapping for display or reproduction of HDR images on devices with lower dynamic range capability. An example system may include a log-conversion circuit to convert luminance data, from a received image, to a logarithm domain. The system may also include an edge-aware filter circuit to decompose the log domain luminance data into a base layer, a small scale detail layer, and a large scale detail layer. The system may further include an amplitude adjustment circuit to shift and scale data amplitudes in each of the layers to a selected range and a linear-conversion circuit to convert the adjusted layers from the log domain back to the linear domain. The system may further include a tone compression circuit to generate compressed linear domain layers and a luminance data reconstruction circuit to generate compressed luminance data based on the compressed linear domain layers.

主权项

1. A processor-implemented method for spatially adaptive tone mapping, the method comprising:
extracting, by a processor, luminance data associated with pixels from a received image; converting, by the processor, the luminance data to a logarithm domain; decomposing, by the processor, the logarithm domain luminance data into a base layer, a small scale detail layer, and a large scale detail layer; adjusting, by the processor, amplitudes of data in each of the layers, the adjusting to shift and scale the amplitudes of the base layer and to scale the amplitudes of the small scale layer and the large scale layer, to map the amplitude data into a selected range; converting, by the processor, the adjusted layers from the logarithm domain to a linear domain; applying, by the processor, a global tone compression function to the converted linear domain base layer to generate compressed linear domain layers; and generating, by the processor, compressed luminance data based on a multiplicative product of the compressed linear domain layers.