Abstract: A controller for a multi-primary display having M>3 primaries receives a set of input N-primary image color defining values comprising drive values for N primaries for each pixel. A compensator (317) generates a set of compensated N-primary image color (N>=3) defining values by applying a luminance compensation to the values of the set of input N-primary image color defining values where the luminance compensation for each pixel depends on the chromaticity of the pixel. A backlight processor (311) determines backlight levels in response to the compensated N-primary image color defining values. A modifier (313) then generates modified N-primary image color defining values by adjusting the input or the modified N-primary image color defining values or the for the backlight level and a primary converter (315) converts the modified N-primary image color defining values into multi-primary drive values for the display. The approach may e.g.

Abstract: Clusters of pixels are defined for use in image compression and decompression. The image information used to define the clusters may include pixel values at predetermined positions relative to a pixel or related motion vectors, gradients, texture etc. During compression of images the image information relative to pixels is examined to determine the cluster to which it belongs. Thus pixels can be classified according to the cluster for their image information. In an embodiment the definitions of the clusters are selected dynamically, dependent on image content. For each cluster a control parameter set is computed for a post-processing operation, such as filter coefficients for filtering or statistical data for locally generating texture. The control parameter set is selected dependent on the image content so that, when the post-processing operation is applied to the image after decompression it will improve image quality for the pixels that are classified as belonging to the cluster.

Abstract: A multi-primary conversion (5) of input drive values (RGB) defines a color of a pixel (PI) of a multi-primary display(DP) in an M dimensional color space (XYZ) into N>M output drive values (di) in an N dimensional drive space. The N output drive values (di) drive N sub-pixels (SPi) of the pixel (PI). The color of the pixel (PI) in the color space (XYZ) is defined by linear combinations of N color primaries of the respective N sub-pixels (SPi).

Abstract: Clusters of pixels are defined for use in image compression and decompression. The image information used to define the clusters may include pixel values at predetermined positions relative to a pixel or related motion vectors, gradients, texture etc. During compression of images the image information relative to pixels is examined to determine the cluster to which it belongs. Thus pixels can be classified according to the cluster for their image information. In an embodiment the definitions of the clusters are selected dynamically, dependent on image content. For each cluster a control parameter set is computed for a post-processing operation, such as filter coefficients for filtering or statistical data for locally generating texture. The control parameter set is selected dependent on the image content so that, when the post-processing operation is applied to the image after decompression it will improve image quality for the pixels that are classified as belonging to the cluster.