This paper discusses the many and varied design considerations for the 2-D digital video filters that are used in the implementation of an HDTV encoder which enables PALplus-compatible transmissions. In particular, the design trade-offs and overall performance of a quadrature mirror filter pair, which is used in combination with a 2-D diagonal prefilter is explored and the ensuing problems of crosstalk and signal reconstruction at the decoder are highlighted. The difficulties encountered in processing an interlaced HDTV signal are also examined and an effective solution propose