Abstract: A method of and a device for speech signal digital coding are described, where spectral parameters are quantized at each frame in order to exploit the actual correlation inside a frame or between contiguous frames. The quantization devices (DQ) recognize strongly correlated signal periods by using a first set of indexes (j.sub.1), representing the parameters and provided by the spectral analysis circuits (ABT, ALT), and in these periods they convert the same indexes into a second set of indexes (j4) which can be coded with a lower number of bits and which is inserted into the coded signal in place of the first set.

Abstract: An interface module for superimposing alphanumeric characters upon external GB video signals received by a SCART connector of a television set is disclosed. The interface includes a central processing unit (CPU) controlling the command input from an alphanumeric keyboard, remote control, touch screen functions, and message exchange with a processing center through the D channel of an ISDN network. The CPU controls a video display processor which outputs a switching signal to the SCART connector and R, G, B video signals to an encoder which encodes a composite color signal in a standard format such as PAL, SECAM or NTSC. The superimposing is done in the SCART connector by switching between the external R, G, B video signals and the composite color video from the encoder.