Abstract: An adaptive method for television image encoding by splitting the video image to be transmitted into sub-bands at the time of analysis filtering of the image encoder. These sub-bands are split into a tree-like structure by filtering and decimation. Local adaptive filtering is carried out in the analysis filters of each sub-band.

Abstract: The present invention concerns a processing method for a video signal coded in the form of blocks of K words, this signal being written to or read from two frame memories (FM1, FM2) each including an input port, a high speed output port and a low speed output port. According to this method, the input digital video signal is formed by sets of M' blocks with N' block containing luminance data (Y1, Y2 . . . ) and M'-N' blocks containing chrominance data (C1, C2 . . . ), the blocks containing the chrominance data (C1) are written in the first memory (FM1) and the blocks containing luminance data (Y1) are written in the second memory (FM2). Then the blocks containing the luminance data and the blocks containing the chrominance data are read simultaneously on the high speed output port of each memory, the memories being inverted at each frame, and the data eventually being processed to obtain video data in output that presents a compression ratio M/N with M>N.

Abstract: A method for displaying a supplementary video image outside a main image. For example, the main image has a 4/3 aspect ratio and the tube has a 16/9 aspect ratio. The method includes steps of processing a supplementary video image at the time of the line return of the main image to provide a video signal of the desired format. Then, multiplexing the components of the main video signal with the components of the supplementary video signal; and then separately processing the components of the multiplexed signal to produce the components of the display signal for a display on the tube. The displayed image has the main 4/3 aspect ratio image in 4/3 aspect ratio occupying approximately 12/9 of the screen and supplementary video images occupying the remaining 4/9 of the screen.

Abstract: A video signal processor as for generating a picture-in-picture signal, generates respective analog luminance components and first and second analog chrominance components. In order to reduce the system hardware and processing speed, multiplexing circuitry subsamples the luminance and chrominance components on a field basis to provide alternating fields of only luminance and only chrominance signal. The multiplexing circuitry further subsamples the chrominance components by providing groups of horizontal lines of only the first chrominance component alternating with groups of horizontal lines of only the second chrominance component.