Patent ID: 6018366
Filing Date: 2000-01-25
Classification: H04N

Abstract:
A video encoder, having a quantizer for quantizing format-transformed source input-pictures into quantized data, and having a coder for coding the quantized data into a coded bitstream, and for outputting the coded bitstream, comprising:a first plural-density format-transformer for transforming from among a plurality of density formats a source input-picture into a specific format-transformed source input-picture, and for inputting the specific format-transformed input-picture into the quantizer;a detector for detecting a variation in at least one of a luminance and color difference related component, and for selecting said specific format-transformed source input-picture for input to the quantizer depending on the variation; anda coder loop having:a frame memory for storing a reference picture;a second plural-density format-transformer for transforming the quantized data into a specific reference picture to serve as the reference picture stored in said frame memory; anda third plural-density format-transformer for transforming the specific reference picture, after a motion compensating prediction operation is performed into a motion compensated reference picture for feedback to an output of said detector;wherein the detector selects corresponding outputs of the second plural-density format-transformer and the third plural-density format-transformer.