Anordnung mit einer verbesserten Gleichstrompegelauswertungsvorrichtung.

摘要

The apparatus performs a processing operation on the signal in a transmission system, this signal conveying analog luminance and chrominance information components associated with periods of the coded digital signal. A receiver in a MAC television system is, for example, such a device. The device for recovering the d.c. component includes encoding member (4) which, from the decoded digital signal, realizes an encoding operation of the type used for the creation of the received signal, an estimation circuit for the d.c. component (6) calculating the estimation from the difference between the received coded signal and the recovered coded signal by the encoding member, this estimation constituting d.c. component correction signal, and a subtraction circuit (9) which, from the digital signal received, subtracts the d.c. component correction signal throughout the duration of a line. The apparatus also includes, downstream of the device (6) which supplies the d.c. component correction signal, a filter (8) which utilizes d.c. component correction signals of several line scanning periods simultaneously to improve the d.c. component correction signal, which is of the finite-impulse-response type, for example a mean-value taking circuit, and the received signal is delayed (10) for compensating for delay caused by the filter, before being conveyed to the subtraction circuit (9).