초록 ▼

In a method in which the data related to the image are read in successive blocks, then subjected to orthogonal transformation, the coefficients of the transform obtained being quantized and analyzed according to a certain order and applied in the form of binary signals to a redundancy reducing coder

In a method in which the data related to the image are read in successive blocks, then subjected to orthogonal transformation, the coefficients of the transform obtained being quantized and analyzed according to a certain order and applied in the form of binary signals to a redundancy reducing coder, the signals representing the coefficients of the transform are stored in a memory organized in several blocks, and the contents of said memory are analyzed such that the signals applied to the redundancy reducing coder comprise sets of signals of coefficients taken from a group of blocks, the signals of each coefficient in each set being taken from a separate block belonging to said group of blocks.

대표청구항 ▼

A method of coding video signals comprising: reading data relative to a a still or moving video image in successive blocks; subjecting the data to orthogonal transformation; quantizing the transformed coefficients; storing by rank signals representing the coefficients in organized blocks of memory;

A method of coding video signals comprising: reading data relative to a a still or moving video image in successive blocks; subjecting the data to orthogonal transformation; quantizing the transformed coefficients; storing by rank signals representing the coefficients in organized blocks of memory; retrieving from memory signals representing the coefficients in groups of blocks, in a predetermined scanning order, the signals of each coefficient in each set being taken in a separate block belonging to said group of blocks; and applying the coefficients of the transformation in the form of binary signals to a variable length coder. A method of coding video signals comprising: reading data relative to a still or moving video image in successive blocks; subjecting the data to orthogonal transformation; quantizing the coefficients of the transformation; and applying the coefficients of the transformation to a redundancy reducing coder; wherein each one of the transformed coefficients (Yn1n2) of the transformation is obtained by multiplying the transformed coefficients (Xn1n2) of a unitary transformation known in itself by factors (√Wn1n2) such that the quantization noise power weighted by the sensitivity of the eye as a function of the spatial frequencies is minimal, said weighting being carried out independently of the statistical properties of the images.