A high dynamic range video encoder, arranged to receive via an image input an input high dynamic range image (MsterHDR) which has a first maximum pixel luminance (PB_C_H50) for which the encoder has a first metadata input, and arranged to receive via a second metadata input a master luma mapping function (FL_50t1), which luma mapping function defines the relationship between normalized lumas of the input high dynamic range image and normalized lumas of a corresponding low dynamic range image (Im_LDR) having an LDR maximum pixel luminance, preferably being equal to 100 nit, characterized in that the encoder further comprises a third metadata input to receive a second maximum pixel luminance (PB_CH), which is lower than the first maximum pixel luminance (PB_C_H50), and the encoder further being characterized in that it comprises: - a HDR function generation unit arranged to apply an algorithm for transforming input luma mapping functions into output luma mapping functions, which algorithm is pre-agreed between the high dynamic range video encoder and a set of receivers, to transform the master luma mapping function (FL_50t1) into an adapted luma mapping function (F_H2hCI), which relates normalized lumas of the input high dynamic range image to normalized luminances of an intermediate dynamic range image which is characterized by having a maximum possible luminance being equal to the second maximum pixel luminance (PB_CH), in which the algorithm creates the adapted luma mapping function (F_H2hCI) of similar shape as the master luma mapping function (FL_50t1) but closer to an identity transform, wherein the similarity of shape is determined by shifting along a metric any point of the input function closer to a diagonal of a representation of normalized lumas; - an IDR image calculation unit arranged to apply the adapted luma mapping function (F_H2hCI) to lumas of pixels of the input high dynamic range image (MsterHDR) to obtain lumas of pixels of the intermediate dynamic range image which is output of this unit; and - an IDR mapping function generator arranged to derive on the basis of the master luma mapping function (FL_50t1) and the adapted luma mapping function (F _H2hCI) a channel luma mapping function (F_I2sCI), which defines as output the respective normalized lumas of the low dynamic range image (Im_LDR) when given as input the respective normalized lumas of the intermediate dynamic range image, which in turn correspond to respective lumas of the input high dynamic range image (MsterHDR); the encoder being further characterized to have: - an image output to output the intermediate dynamic range image; - a first metadata output to output the second maximum pixel luminance (PB_CH); - a second metadata output to output the channel luma mapping function (F_I2sCI); and - a third metadata output to output the first maximum pixel luminance (PB_C_H50). - a HDR function generation unit arranged to apply an algorithm for transforming input luma mapping functions into output luma mapping functions, which algorithm is pre-agreed between the high dynamic range video encoder and a set of receivers, to transform the master luma mapping function (FL_50t1) into an adapted luma mapping function (F_H2hCI), which relates normalized lumas of the input high dynamic range image to normalized luminances of an intermediate dynamic range image which is characterized by having a maximum possible luminance being equal to the second maximum pixel luminance (PB_CH), in which the algorithm creates the adapted luma mapping function (F_H2hCI) of similar shape as the master luma mapping function (FL_50t1) but closer to an identity transform, wherein the similarity of shape is determined by shifting along a metric any point of the input function closer to a diagonal of a representation of normalized lumas; - an IDR image calculation unit arranged to apply the adapted luma mapping function (F_H2hCI) to lumas of pixels of the input high dynamic range image (MsterHDR) to obtain lumas of pixels of the intermediate dynamic range image which is output of this unit; and - an IDR mapping function generator arranged to derive on the basis of the master luma mapping function (FL_50t1) and the adapted luma mapping function (F _H2hCI) a channel luma mapping function (F_I2sCI), which defines as output the respective normalized lumas of the low dynamic range image (Im_LDR) when given as input the respective normalized lumas of the intermediate dynamic range image, which in turn correspond to respective lumas of the input high dynamic range image (MsterHDR); the encoder being further characterized to have: - an image output to output the intermediate dynamic range image; - a first metadata output to output the second maximum pixel luminance (PB_CH); - a second metadata output to output the channel luma mapping function (F_I2sCI); and - a third metadata output to output the first maximum pixel luminance (PB_C_H50). - an image output to output the intermediate dynamic range image; - a first metadata output to output the second maximum pixel luminance (PB_CH); - a second metadata output to output the channel luma mapping function (F_I2sCI); and - a third metadata output to output the first maximum pixel luminance (PB_C_H50).