Method and apparatus for colour correction during hdr to sdr conversion

A device comprising means for:

• deriving chroma components (C122, C123) of a third image by correcting chroma components (C12, C13) of a second image according to a luma component (C1,pre1) of said second image and a reconstructed component obtained by applying a mapping function to said luma component (C1,pre1) of said second image, said chroma components (C12, C13) of the second image being obtained by applying a conversion matrix to components (C10m) of a first image;
• and
• adapting coefficients of the conversion matrix which are relative to a chroma component of said third image independently of coefficients of the conversion matrix which are relative to another chroma component of said third image to ensure that there is no clipping on chroma components of the third image.

A signal carrying an information data representative of a correction intended to be used to adapt coefficients of a conversion matrix which are relative to a chroma component of an image independently of coefficients of the conversion matrix which are relative to another chroma component of said image.