MULTIRANGE ENCODING OF VIDEO WITH EXPANDED DYNAMIC RANGE Russian patent published in 2023 - IPC H04N19/98 

FIELD: image encoding.

SUBSTANCE: invention relates to methods and devices for encoding of images with an expanded dynamic range. Encoder (900) of video with an expanded dynamic range is made with the possibility of reception through image input (920) of an input image (MsterHDR) with an expanded dynamic range, which has the first maximum pixel luminosity (PB_C_H50). At the same time, the encoder is made with the possibility of reception through metadata input (921) of the main brightness display function (FL_50t1), which determines the relationship between normalized brightness of the input image with an expanded dynamic range and normalized brightness of the corresponding image (Im_LDR) with a standard dynamic range, having the maximum pixel luminosity of preferably 100 nits. In this case, the encoder contains metadata input (923) for reception of the second maximum pixel luminosity (PB_CH). The encoder additionally contains HDR function generation block (901) made with the possibility of use of a standardized algorithm for conversion of the main brightness display function (FL_50t1) into an adapted brightness display function (F_H2hCI), which links normalized brightness of the input image with an expanded dynamic range with normalized brightness of an image with an intermediate dynamic range (hereinafter – IDR), which differs in the maximum possible luminosity equal to the second maximum pixel luminosity (PB_CH); IDR image calculation block (902) made with the possibility of use of the adapted brightness display function (F_H2hCI) to brightness of pixels of the input image (MsterHDR) with an expanded dynamic range to obtain brightness of pixels of IDR image; and IDR display function generator (903) made with the possibility of reception, based on the main brightness display function (FL_50t1) and the adapted brightness display function (F_H2hCI), of a channel brightness display function (F_I2sCI), which determines, as output data, corresponding normalized brightness of the image (Im_LDR) with a standard dynamic range, when corresponding normalized brightness of IDR image is set as input data. In this case, the encoder additionally outputs IDR image, the second maximum pixel luminosity (PB_CH) as the first metadata, the channel brightness display function (F_I2sCI) as the second metadata, and the first maximum pixel luminosity (PB_C_H50) as the third metadata.

EFFECT: provision of encoding of images with an expanded dynamic range with adapted brightness data for displays with different capacities of display of a dynamic range of image brightness.

13 cl, 28 dwg