An image processing method for tone adapting an image to a target peak luminance LT of a target display device from a low dynamic range version of this image adapted to be displayed on a display device having a low peak luminance LLDR, and from high dynamic range expansion exponents EHDR(p) to be applied to low dynamic range luminance values YLDR(p) or to low pass filtered luminance values of said low dynamic range version of said image to get expanded luminance values YHDR(p) of a high dynamic range version of said image adapted to be displayed on a display device having a high peak luminance LHDR, said method comprising, for a pixel p in the image: - obtaining low dynamic range expansion exponents ELDR(p) such that, when applied to low dynamic range luminance values YLDR(p) orto low pass filtered luminance values of said low dynamic range version of said image, low dynamic range luminance values YLDR(p) are linearly scaled from a low dynamic range [0, NLDR] to a high dynamic range [0, LHDR] by a factor LHDR / NLDR, wherein ELDR p = 1, if YLDR p = 1, and ELDR p = 1 + log LHDR / NLDR / log YLDR p, otherwise, - obtaining target expansion exponents ET(p) as a weighted sum of the high dynamic range expansion exponents EHDR(p) and of the obtained low dynamic range expansion exponents ELDR(p), with a weight 0 ≤ α_in ≤ 1 of the high dynamic range expansion exponent EHDR(p) and with a weight of the low dynamic range expansion exponent ELDR(p) equal to (1- α_in), wherein the weight α_in of the high dynamic range expansion exponent EHDR(p) is proportional to a difference between the target peak luminance LT of the target display device and the low peak luminance LLDR, this difference being scaled by another difference between the high peak luminance LHDR and the low peak luminance LLDR, - applying obtained target expansion exponent ET(p) to low dynamic range luminance values YLDR(p) or to low pass filtered luminance values of said low dynamic range version of said image, and applying a scaling function Ys(p), resulting in target luminance values YT, - building a tone-adapted version of said image based on said target luminance values YT. - obtaining low dynamic range expansion exponents ELDR(p) such that, when applied to low dynamic range luminance values YLDR(p) orto low pass filtered luminance values of said low dynamic range version of said image, low dynamic range luminance values YLDR(p) are linearly scaled from a low dynamic range [0, NLDR] to a high dynamic range [0, LHDR] by a factor LHDR / NLDR, - obtaining target expansion exponents ET(p) as a weighted sum of the high dynamic range expansion exponents EHDR(p) and of the obtained low dynamic range expansion exponents ELDR(p), with a weight 0 ≤ α_in ≤ 1 of the high dynamic range expansion exponent EHDR(p) and with a weight of the low dynamic range expansion exponent ELDR(p) equal to (1- α_in), wherein the weight α_in of the high dynamic range expansion exponent EHDR(p) is proportional to a difference between the target peak luminance LT of the target display device and the low peak luminance LLDR, this difference being scaled by another difference between the high peak luminance LHDR and the low peak luminance LLDR, - applying obtained target expansion exponent ET(p) to low dynamic range luminance values YLDR(p) or to low pass filtered luminance values of said low dynamic range version of said image, and applying a scaling function Ys(p), resulting in target luminance values YT, - building a tone-adapted version of said image based on said target luminance values YT.