Abstract: To enable a high quality HDR video communication, which can work by sending corresponding LDR images potentially via established LDR video communication technologies, which works well in practical situations, applicant has invented a HDR video decoder (600, 1100) arranged to calculate a HDR image (Im_RHDR) based on applying to a received 100 nit standard dynamic range image (Im_RLDR) a set of luminance transformation functions, the functions comprising at least a coarse luminance mapping (FC), which is applied by a dynamic range optimizer (603), and a mapping of the darkest value (0) of an intermediate luma (Y?HPS), being output of the dynamic range optimizer, to a received black offset value (Bk_off) by a range stretcher (604), the video decoder comprising a gain limiter (611, 1105) arranged to apply an alternate luminance transformation function to calculate a subset (502) of the darkest luminances of the HDR image, from corresponding darkest lumas (Y?_in) of the standard dynamic range image.

Abstract: To enable a high quality HDR video communication, which can work by sending corresponding LDR images potentially via established LDR video communication technologies, which works well in practical situations, applicant has invented a HDR video decoder (600, 1100) arranged to calculate a HDR image (Im_RHDR) based on applying to a received 100 nit standard dynamic range image (Im_RLDR) a set of luminance transformation functions, the functions comprising at least a coarse luminance mapping (FC), which is applied by a dynamic range optimizer (603), and a mapping of the darkest value (0) of an intermediate luma (Y?HPS), being output of the dynamic range optimizer, to a received black offset value (Bk_off) by a range stretcher (604), the video decoder comprising a gain limiter (611, 1105) arranged to apply an alternate luminance transformation function to calculate a subset (502) of the darkest luminances of the HDR image, from corresponding darkest lumas (Y?_in) of the standard dynamic range image.

Abstract: To enable a high quality HDR video communication, which can work by sending corresponding LDR images potentially via established LDR video communication technologies, which works well in practical situations, applicant has invented a HDR video decoder (600, 1100) arranged to calculate a HDR image (Im_RHDR) based on applying to a received 100 nit standard dynamic range image (Im_RLDR) a set of luminance transformation functions, the functions comprising at least a coarse luminance mapping (FC), which is applied by a dynamic range optimizer (603), and a mapping of the darkest value (0) of an intermediate luma (Y?HPS), being output of the dynamic range optimizer, to a received black offset value (Bk_off) by a range stretcher (604), the video decoder comprising a gain limiter (611, 1105) arranged to apply an alternate luminance transformation function to calculate a subset (502) of the darkest luminances of the HDR image, from corresponding darkest lumas (Y?_in) of the standard dynamic range image.

Abstract: To enable good quality HDR image decoding, as corresponding SDR images which are typically defined in a narrower Rec.

Abstract: For serving the new different needs of high dynamic range image handling and conversion of images to a different dynamic range in decoding strategies the inventor invented image encoder (201) for encoding at least one high dynamic range image (HDR_ORIG) for at least one time instant, and at least one image (Im_LDR_out) of a second dynamic range which is different from the one of the high dynamic range image by at least a factor two for the same time instant, which is arranged to encode a matrix of pixel colors for at least one of those two images, comprising a specification unit (212) which comprises a color saturation modification apparatus (202) as claimed in claim 1, and a saturation specification unit (204) arranged to specify a saturation modification specification function specifying a color-dependent saturation transformation, as a set of gains (g) for each possible value of a maximal one of at least two color difference values (R?-Y?, B?-Y?) of a pixel color (Y?,Cb,Cr), which color difference values a

Abstract: To enable a high quality HDR video communication, which can work by sending corresponding LDR images potentially via established LDR video communication technologies, which works well in practical situations, applicant has invented a HDR video decoder (600, 1100) arranged to calculate a HDR image (Im_RHDR) based on applying to a received 100 nit standard dynamic range image (Im_RLDR) a set of luminance transformation functions, the functions comprising at least a coarse luminance mapping (FC), which is applied by a dynamic range optimizer (603), and a mapping of the darkest value (0) of an intermediate luma (Y?HPS), being output of the dynamic range optimizer, to a received black offset value (Bk_off) by a range stretcher (604), the video decoder comprising a gain limiter (611, 1105) arranged to apply an alternate luminance transformation function to calculate a subset (502) of the darkest luminances of the HDR image, from corresponding darkest lumas (Y?_in) of the standard dynamic range image.

Abstract: To enable a high quality HDR video communication, which can work by sending corresponding LDR images potentially via established LDR video communication technologies, which works well in practical situations, applicant has invented a HDR video decoder (600, 1100) arranged to calculate a HDR image (Im_RHDR) based on applying to a received 100 nit standard dynamic range image (Im_RLDR) a set of luminance 5 transformation functions, the functions comprising at least a coarse luminance mapping (FC), which is applied by a dynamic range optimizer (603), and a mapping of the darkest value (0) of an intermediate luma (Y?HPS), being output of the dynamic range optimizer, to a received black offset value (Bk_off) by a range stretcher (604), the video decoder comprising a gain limiter (611, 1105) arranged to apply an alternate luminance transformation function to 10 calculate a subset (502) of the darkest luminances of the HDR image, from corresponding darkest lumas (Y?_in) of the standard dynamic range image.

Abstract: To have a much better usable pragmatic manner of HDR video encoding and decoding, the inventor invented a high dynamic range video decoder (500) arranged to receive an encoding (Im_COD) of a high dynamic range video and to decode and output a set of temporally successive images (Im_RHDR) comprising: An input (502) to receive three weight values (kRY, kGY, kBY); A video decoder (501) arranged to decode the encoding (Im_COD) into an intermediate image (Im_RLDR) being in a Y?CbCr color representation; A brightness index calculation unit (503) arranged to calculate for each pixel of the intermediate image (Im_RLDR) a brightness index (J?) being defined as J?=Y?+MAX{kRY*(R??Y?), kGY*(G??Y?), kBY*(B??Y?)}; A brightness mapper (505) arranged to receive a specification of at least one one-dimensional function F_ct, and to apply it with the brightness index (J?) as input, to obtain an output brightness index (J*); A multiplication factor calculation unit (506) arranged to calculate a multiplicative factor (g) being eq

Abstract: To enable good quality HDR image decoding, as corresponding SDR images which are typically defined in a narrower Rec.

Abstract: An image color processing apparatus to change a luminance dynamic range includes a maximum calculation unit configured to calculate the maximum of at least three components of the input color; a brightness mapper configured to apply a predetermined function to the maximum, yielding an output value, where the function has a constraint that the output value for the highest value of the maximum cannot be higher than 1.0; a scaling parameter calculator configured to calculate a scaling parameter being equal to the output value divided by the maximum; a multiplier configured to multiply the three color components of the input color by the scaling parameter, yielding the color components of the output color; and at least one component multiplier configured to multiply a component of the input color with a weight being a real number yielding a scaled component prior to input of that component in the maximum calculation unit.

Abstract: Because we needed a new color saturation processing in tune with dynamic range transformations necessary for handling the recently introduced high dynamic range image encoding, we describe a color saturation modification apparatus (101) arranged to determine linear color differences (R-Y,G-Y,B-Y) on the basis of an input color (R,G,B) and a luminance (Y) of the input color, and to do a multiplication of the linear color differences (R-Y,G-Y,B-Y) with a gain (g), characterized in that the apparatus is arranged to determine the gain as a function of a difference value (V_in-Y) being defined as the value of the highest one of the linear color differences (R-Y,G-Y,B-Y).

Abstract: To enable a high quality HDR video communication, which can work by sending corresponding LDR images potentially via established LDR video communication technologies, which works well in practical situations, applicant has invented a HDR video decoder (600, 1100) arranged to calculate a HDR image (Im_RHDR) based on applying to a received 100 nit standard dynamic range image (Im_RLDR) a set of luminance 5 transformation functions, the functions comprising at least a coarse luminance mapping (FC), which is applied by a dynamic range optimizer (603), and a mapping of the darkest value (0) of an intermediate luma (Y?HPS), being output of the dynamic range optimizer, to a received black offset value (Bk_off) by a range stretcher (604), the video decoder comprising a gain limiter (611, 1105) arranged to apply an alternate luminance transformation function to 10 calculate a subset (502) of the darkest luminances of the HDR image, from corresponding darkest lumas (Y?_in) of the standard dynamic range image.

Abstract: To have a much better usable pragmatic manner of HDR video encoding and decoding, the inventor invented a high dynamic range video decoder (500) arranged to receive an encoding (Im_COD) of a high dynamic range video and to decode and output a set of temporally successive images (Im_RHDR) comprising: An input (502) to receive three weight values (kRY, kGY, kBY); A video decoder (501) arranged to decode the encoding (Im_COD) into an intermediate image (Im_RLDR) being in a Y?CbCr color representation; A brightness index calculation unit (503) arranged to calculate for each pixel of the intermediate image (Im_RLDR) a brightness index (J?) being defined as J?=Y?+MAX{kRY*(R??Y?), kGY*(G??Y?), kBY*(B??Y?)}; A brightness mapper (505) arranged to receive a specification of at least one one-dimensional function F_ct, and to apply it with the brightness index (J?) as input, to obtain an output brightness index (J*); A multiplication factor calculation unit (506) arranged to calculate a multiplicative factor (g) being eq

Abstract: For serving the new different needs of high dynamic range image handling and conversion of images to a different dynamic range in decoding strategies the inventor invented image encoder (201) for encoding at least one high dynamic range image (HDR_ORIG) for at least one time instant, and at least one image (Im_LDR_out) of a second dynamic range which is different from the one of the high dynamic range image by at least a factor two for the same time instant, which is arranged to encode a matrix of pixel colors for at least one of those two images, comprising a specification unit (212) which comprises a color saturation modification apparatus (202) as claimed in claim 1, and a saturation specification unit (204) arranged to specify a saturation modification specification function specifying a color-dependent saturation transformation, as a set of gains (g) for each possible value of a maximal one of at least two color difference values (R?-Y?, B?-Y?) of a pixel color (Y?,Cb,Cr), which color difference values a

Abstract: For obtaining an good yet easy to use luminance dynamic range conversion, we describe an image color processing apparatus (200) arranged to transform an input color (R,G,B) of a pixel of an input image (Im_in) having a first luminance dynamic range into an output color (Rs, Gs, Bs) of a pixel of an output image (Im_res) having a second luminance dynamic range, which first and second dynamic ranges differ in extent by at least a multiplicative factor 2, comprising: a maximum determining unit (101) arranged to calculate a maximum (M) of color components of the input color, the color components at least comprising a red, green and blue component;—a uniformization unit (201) arranged to apply a function (FP) to the maximum (M) as input, which function has a logarithmic shape and was predetermined to be of a fixed shape enabling to transform a linear input to a more perceptually uniform output variable (u); a function application unit (203) arranged to receive a functional shape of a function, which was specified

Abstract: For obtaining an good yet easy to use luminance dynamic range conversion, we describe an HDR video decoder (250) comprising an image color processing apparatus (200) arranged to transform an input color (Y?UV_LDR) of a pixel of an input image (Im_in), which input image has a first luminance dynamic range (DR_1), into a red, green and blue color component output color (R?o, G?o, B?o) of a pixel of an output image (Im_res; REC_HDR), which output image has a second luminance dynamic range (DR_2), whereby the peak luminance of the first dynamic range is at least 2 times lower than the peak luminance of the second dynamic range or vice versa, comprising a coarse mapping unit (202; 552) arranged to apply a three-segment brightness re-grading curve which consists of a linear segment for a dark sub-range (SR_d) of the range of lumas of the input image colors comprising the darkest input luma values, which is determined by a slope variable (InvBet), a second linear segment for the lightest input luma values in a brigh

Abstract: For obtaining an good yet easy to use luminance dynamic range conversion, we describe an HDR video decoder (250) comprising an image color processing apparatus (200) arranged to transform an input color (Y?UV_LDR) of a pixel of an input image (Im_in), which input image has a first luminance dynamic range (DR_1), into a red, green and blue color component output color (R?o, G?o, B?o) of a pixel of an output image (Im_res; REC_HDR), which output image has a second luminance dynamic range (DR_2), whereby the peak luminance of the first dynamic range is at least 2 times lower than the peak luminance of the second dynamic range or vice versa, comprising a coarse mapping unit (202; 552) arranged to apply a three-segment brightness re-grading curve which consists of a linear segment for a dark sub-range (SR_d) of the range of lumas of the input image colors comprising the darkest input luma values, which is determined by a slope variable (InvBet), a second linear segment for the lightest input luma values in a brigh

Abstract: For obtaining an good yet easy to use luminance dynamic range conversion, we describe an image color processing apparatus (200) arranged to transform an input color (R,G,B) of a pixel of an input image (Im_in) having a first luminance dynamic range into an output color (Rs, Gs, Bs) of a pixel of an output image (Im_res) having a second luminance dynamic range, which first and second dynamic ranges differ in extent by at least a multiplicative factor 2, comprising: a maximum determining unit (101) arranged to calculate a maximum (M) of color components of the input color, the color components at least comprising a red, green and blue component; —a uniformization unit (201) arranged to apply a function (FP) to the maximum (M) as input, which function has a logarithmic shape and was predetermined to be of a fixed shape enabling to transform a linear input to a more perceptually uniform output variable (u); a function application unit (203) arranged to receive a functional shape of a function, which was specified

Abstract: For obtaining good quality luminance dynamic range conversion, we describe an image color processing apparatus (200) arranged to transform an input color (R,G,B) of a pixel of an input image (Im_R2) having a first luminance dynamic range into an output color (Rs, Gs, Bs) of a pixel of an output image (Im_res) having a second luminance dynamic range, which first and second dynamic ranges differ in extent by at least a multiplicative factor 1.5, comprising: a maximum calculation unit (201) arranged to calculate the maximum (M) of at least three components of the input color; a brightness mapper (202) arranged to apply a function (F) to the maximum, yielding an output value (F(M)), whereby the function is predetermined having a constraint that the output value for the highest value of the maximum (M) cannot be higher than 1.

Abstract: Because we needed a new color saturation processing in tune with dynamic range transformations necessary for handling the recently introduced high dynamic range image encoding, we describe a color saturation modification apparatus (101) arranged to determine linear color differences (R-Y,G-Y,B-Y) on the basis of an input color (R,G,B) and a luminance (Y) of the in-put color, and to do a multiplication of the linear color differences (R-Y,G-Y,B-Y) with a gain (g), characterized in that the apparatus is arranged to determine the gain as a function of a difference value (V_in-Y) being defined as the value of the highest one of the linear color differences (R-Y,G-Y,B-Y).