A method for obtaining line synchronization information items from a video
signal is proposed. The inventive method is based on convolving the
relevant part of an analogue video line signal with a pattern function.
The result of the convolution operation is further processed to determine
the time instants of the occurrence of the horizontal sync signals. The
time instants are subsequently filtered to generate horizontal pulses. A
video line memory allows to utilize subsequent horizontal sync signals
for calculating the horizontal sync pulse of a current video line. The
invention also relates to an apparatus for carrying out the method.