Patent attributes
An apparatus generates an image coding signal comprising for each image a first pixelized picture and a second pixelized picture having a luminance component and a chroma component. The apparatus comprises a first picture processor (203, 211) which includes image encoding data for an encoded first image in the first pixelized picture. A second picture processor (205, 207, 209, 211) includes dynamic range extension data in the second pixelized picture. The dynamic range extension data may be dynamic range extension data included in a chroma component of the second pixelized picture for generating an increased dynamic range image on the basis of the encoded first image. The compensation data may e.g. be compensation data for correcting another LDR-to-HDR transform, e.g. a prefixed global gamma transformation. The dynamic range extension data may be included in a luminance component and comprise data representing a dynamic range extension transform for generating an increased dynamic range image from the encoded first image.