Patent ID: 6175592
Filing Date: 2001-01-16
Classification: G06T,H04N

Abstract:
An apparatus for forming a low resolution video signal from an encoded video signal representing a video image, the encoded video signal being a frequency-domain transformed high resolution video signal, the apparatus comprising:means for receiving and for providing the encoded video signal as a plurality of high resolution frequency-domain video coefficient values;down conversion filter means for receiving and weighting selected ones of the plurality of high resolution frequency-domain video coefficient values to form a set of filtered frequency-domain video coefficients, wherein the down conversion filter means is a lowpass filter represented by a set of frequency domain filter coefficients, and the down conversion filter means weights the selected ones of the plurality of high resolution frequency-domain video coefficient values by multiplying the set of frequency domain filter coefficients with the plurality of high resolution frequency-domain video coefficient values;inverse-transform means for receiving and transforming the filtered frequency-domain video coefficients into a set of filtered pixel sample values; anddecimating means for deleting selected ones of the set of filtered pixel sample values to provide the low resolution video signal.