LINE INTERPOLATION CIRCUIT FOR TELEVISION SIGNAL

摘要

PURPOSE:To eliminate the need for a field memory at an output side of a vertical filter by applying a same filter coefficient to the vertical filter for each field and allowing the vertical filter to output repetitively a one-field data. CONSTITUTION:A data is read from a field memory 11 in line sequential way for an even number field period and inputted to a vertical filter 21. The data inputted to the vertical filter 21 is converted into a data by an odd number field again based on a filter coefficient corresponding to an odd number field outputted from a filter coefficient generating circuit 31 started before. An average circuit 61 outputs an average value between a line data inputted from the vertical filter 21 and a one preceding line data inputted from a line memory 51. The output of the average circuit 61 is selected by a switch 71 based on a field identification signal outputted from a field identification signal generating circuit 81 and outputted from a terminal (b) as an even number field data.