Patent ID: 6272179
Filing Date: 2001-08-07
Classification: G06T,H04N

Abstract:
An image coding apparatus which receives an interlaced image signal comprising a color signal for color display of an object and a shape signal indicating a shape of the object and corresponding to the object included in an image space as an input and is operable to perform an adaptive coding process including a frame-by-frame motion compensation coding process and a field-by-field motion compensation coding process for the image signal in macroblock units each comprising a predetermined number of pixels into which the image space is divided, said apparatus comprising:a color motion vector coding unit operable to code either a frame-basis color motion vector or a field-basis color motion vector of a target macroblock to be coded which is used in either the frame-by-frame motion compensation coding process or the field-by-field motion compensation coding process for an interlaced color signal, based on its prediction value; anda shape motion vector coding unit operable to code a frame-basis shape motion vector of the target macroblock which is used in the frame-by-frame motion compensation coding process for an interlaced shape signal, based on a prediction value obtained from a color motion vector and a shape motion vector of a coded macroblock; whereinsaid color motion vector coding unit includes a motion vector conversion device operable to convert field-basis color motion vectors of the coded macroblock into a frame-basis color motion vector of the coded macroblock; andsaid shape motion vector coding unit includes a shape motion vector predictor operable to generate the prediction value of the shape motion vector of the target macroblock based on the frame-basis shape motion vector of the coded macroblock and the frame-basis color motion vector of the coded macroblock output from said motion vector conversion device when the color motion vector of the coded macroblock is the field-basis motion vector.