Patent ID: 6310916
Filing Date: 2001-10-30
Classification: H04N

Abstract:
A method, for use in a video signal encoder, for coding texture information of a video signal which includes the texture information and shape information on each of macroblocks, each macroblock having M.times.M pixels and being dividable into P number of equal-sized DCT-blocks, M and P being positive integers, respectively, comprising the steps of:(a) determining a DCTtype of a target macroblock based on the shape information and the texture information on the target macroblock, wherein the DCTtype represents the more effective coding technique between a progressive and an interlaced coding techniques for encoding the texture information, the step (a) including the steps of:(a11) determining a block type of the target macroblock based on the shape information, wherein the block type is determined as either an object or a boundary macroblock, the boundary macroblock including at least one background pixel located outside an object expressed by the video signal and at least one object pixel located inside the object, and the object macroblock containing only object pixels;(a12) selecting the progressive coding type as the DCTtype of the target macroblock if the target macroblock is the boundary macroblock; and(a13) deciding the DCTtype of the target macroblock by using the texture information if the target macroblock is determined as the object macroblock and providing DCTtype information representing the decided DCTtype;(b) generating encoded texture information by adaptively encoding the texture information through the use of the progressive or the interlaced coding technique in response to the DCTtype, wherein the step (b) includes the steps of:(b11) re-forming the texture information and the shape information in response to the DCTtype;(b12) detecting one or more non-transparent DCT-blocks for the target macroblock based on the re-formed shape information, wherein each non-transparent DCT-block has a DCT-block size and contains at least one object pixel;(b13) converting the re-formed texture information corresponding to each of the non-transparent DCT-blocks into a set of DCT coefficients;(b14) quantizing the set of DCT coefficients to thereby produce a set of quantized DCT coefficients; and(b15) producing the encoded texture information by encoding the sets of quantized DCT coefficients corresponding to all of the non-transparent DCT-blocks;(c1) checking whether there exists at least one non-zero AC component in the set of quantized DCT coefficients corresponding to each of the non-transparent DCT-blocks;(d1) producing CBPY information representing whether each of the sets of quantized DCT coefficients corresponding to the target macroblock contains at least one non-zero AC component therein in conformity with the results of the step (c1); and(e1) providing encoded CBPY information by encoding the CBPY information.