Composite digital video decoder and digital compressor

Abstract

In accordance with an illustrative embodiment of the invention, a composite video signal is decoded as follows. A filtered and optionally re-sampled luminance component is obtained by vertical low-pass filtering the composite video signal using a vertical low-pass filter. The vertical low-pass filter may also be a re-sampler so that the output is optionally a filtered and re-sampled luminance signal. (Note that the use of a single vertical low-pass filter and re-sampler is more efficient than the prior art which uses a luma comb filter followed by a vertical filter/re-sampler to obtain the filtered and optionally re-sampled luminance component). Filtered and re-sampled chrominance components are obtained by first vertically high-pass filtering and re-sampling the composite video signal using a vertical high pass filter/re-sampler. This results in filtered and re-sampled but still quadrature modulated chroma signals. These signals are then demodulated and horizontal low-pass filtered to obtain separate filtered and re-sampled chroma components. (Note this process is more efficient than the prior art which utilizes a chroma comb filter, a demodulator, and a vertical filter/re-sampler to obtain the filtered and re-sampled chroma components). In short, the present invention eliminates the need to directly obtain the Y, U, and V components and then vertically filter and re-sample the Y, U, and V components. Instead, according to the invention, the vertically filtered and re-sampled Y, U, and V components are directly obtained.