SIMPLE BUT FLEXIBLE DYNAMIC RANGE ENCODING Russian patent published in 2020 - IPC H04N19/00 G06T5/50 

FIELD: transmission of video data.

SUBSTANCE: invention is intended for image conversion. HDR video decoder has an image color processing device configured to display an input image (Im_in) input color (Y'UV_LDR), wherein input image has first dynamic range (DR_1) of brightness, in output color (R'o, G'o, B'o) of components of red, green and blue color of output image pixel (Im_res; REC_HDR), wherein output image has second dynamic range (DR_2) of brightness, due to which peak brightness of first dynamic range is at least 2 times lower than peak brightness of second dynamic range or vice versa, an approximate display unit configured to apply a three-segment brightness correction recurrent curve, which consists of a linear segment for dark subrange (SR_d) of a range of brightness signals of colors of input images containing the darkest values of the input brightness signal, which is determined by variable (InvBet) of inclination of second linear segment for lightest values of brightness input signal in bright subrange (SR_br), which is controlled by second inclination variable (InvAlph), and parabolic segment between two linear segments.

EFFECT: technical result is higher image quality.

15 cl, 5 dwg