| 摘要 |
FIELD: information technologies.SUBSTANCE: images are produced in a multi-level codec of the first flow with the first dynamic range and the first colour space, and the second flow of the image with the second dynamic range. The first flow of the image is produced by performance of a local tonal display on the second flow of the image, using the functional form that displays a family of curves of the tonal image, parametrised by means of one parameter, besides, the first dynamic range is less than the second dynamic range, and the first flow of the image is in the base layer, and the second flow of the image is in the expansion layer. The multi-level codec includes a decoder and a coder. The first flow of the image is coded in the base layer using a coder to produce the coded first flow of the image. The coded first flow of the image is decoded using a decoder to produce a decoded first flow of the image. The decoded first flow of the image is converted from the first colour space into the second colour space of the second flow of the image to produce the colour first flow of the image. Parameters of the reverse tonal image are generated on the basis of the converted colour flow of the image and the second flow of the image, where parameters of the reverse tonal image approximate the second flow of the image when applied to the converted colour flow of the image.EFFECT: increased efficiency of coding.20 cl, 15 dwg |
