Abstract: A system for converting digital television signals encoded according to an MPEG standard into standardized analog video signals. The system includes means for generating graphic images and for inserting corresponding image signals in a decoded digital flow of main image signals, a digital decoding unit, and an analog coding unit. The digital decoding unit includes means for providing a flow of multiplexed image signals including a first flow of main image signals and of a second flow of image signals that contains, in addition to the main image signals, possible graphic image signals. The analog coding unit includes a demultiplexer of the flow of multiplexed image signals and two encoders. The two encoders respectively receive the first and second flows, and each respectively provide a digital flow of images encoded according to a color television standard to digital-to-analog converters respectively associated therewith, the digital-to-analog converters providing the standardized analog video signals.

Abstract: The circuit comprises two substantially identical stages (8a, 8b). Each of these two stages (8a, 8b) respectively comprises an input point (10a, 10b) and an output point (11a, 11b) and is arranged to produce, at its output point (11a, 11b), a voltage having an adjustable mean value and variations which are amplified with respect to the variations in the voltage at its respective input point (10a, 10b) with a gain controlled by a gain control signal (Vcg1, Vcg2). The input point (10a) of the first stage (8a) is linked to a decoupling capacitor (30) receiving the input signal (Vin). The output point (11a) of the first stage (8a) supplies the output signal of the circuit (Vout). A comparator (40) is provided for slaving, to a reference voltage (Vref), the voltage at the output point (11b) of the second stage, as well as the mean value of the output signal (Vout).