A system for clock recovery in digital video communication includes a
delay measurement block for generating PCR input signals and for
continuously determining the time interval between successive PCR input
signals. The system also includes a first storage device for generating a
first PCR signal corresponding to the time interval between arrival of
successive PCR input signals and a PCR inter-arrival time computation
filtering device to determine the average time of arrival difference
between successive PCR packets. The system further includes an error
correction device for minimizing error in the average PCR difference
between successive PCR packets, a controlled system clock generator
coupled to the output of the error correction device to generate system
clock, a second storage device for generating a first system clock
output, and a controlled clock period difference computation element for
computing the clock period difference between the first and second system
clock outputs. The controlled clock period difference computation element
is coupled at its output to the error correction device to form a
feedback circuit to minimize error between the system clock output and
successive PCR differences.