Signal CompressionGeneral Coding ArchitectureEncodingEntropycodingPredictionTransformQuantizationTECDecoding
General Coding Architecture Signal Compression Prediction Transform Quantization Entropy coding
MPEG-4Part2.VisualVisual data typesRectangularimageArbitraryshapeobjectBinarymaskGraymaskInformationtoencode:the textureAdditional informationto encode:the shape
Visual data types MPEG-4 Part 2, Visual Rectangular image Arbitrary shape object Binary mask Gray mask Additional information to encode: the shape Information to encode: the texture
MPEG-4Part2.VisualTextureencoding:data representationR-Initial ImageBY=0.299*R+0.587*G+0.114*BR=Y+(1.4075*(V-128);U=-0.169*R-0.331*G+0.500*B+128.0G=Y-(0.3455*(U-128)-(0.7169*(V-128));V=0.500*R-0.419*G-0.081*B+128.0B=Y+(1.7790*(U-128);
Texture encoding: data representation MPEG-4 Part 2, Visual Initial Image Y = 0.299*R + 0.587*G + 0.114*B U = -0.169*R - 0.331*G + 0.500*B + 128.0 V = 0.500*R - 0.419*G - 0.081*B + 128.0 R = Y + (1.4075 * (V - 128)); G = Y - (0.3455 * (U - 128) - (0.7169 * (V - 128)); B = Y + (1.7790 * (U - 128); B R G Y U V
MPEG-4Part2.VisualTextureencoding:datarepresentationSub-sampling4:4:44:2:24:2:0Y(luma)componentcontainsmore information than U and V(chromacomponents!
Texture encoding: data representation MPEG-4 Part 2, Visual Y U V Y (luma) component contains more information than U and V (chroma) components! Subsampling Y U V 4:4:4 4:2:2 Y U V 4:2:0
MPEG-4Part2.VisualTextureencoding:MacroBlock（16x16pixels)16x16pixelsFor the images thus the size is notmultiple of 16,paddingis necessary
Texture encoding: MacroBlock (16x16 pixels) MPEG-4 Part 2, Visual For the images thus the size is not multiple of 16, padding is necessary 16x16 pixels