Slide 1Interim ReportChroma Sub SamplingLayered StructureLayered StructurePicture TypesPredicted Picture (P-Picture)Predicted Picture (P-Picture)Predicted Picture ModesInterpolated Picture (B-Picture)Interpolated Picture (B-Picture)Interpolated Picture ModesInterpolated Picture ModesIntra Picture(I-Picture)Intra-Prediction ModesIntra-Prediction ModesEncoderDecoderResults:ReferencesReferences contd..AVS CHINA, IMPLEMENTATION & PERFORMANCE ANALYSIS OF VIDEO PROFILESVamsi Krishna VeguntaUniversity of Texas, [email protected] Report Color Space: Y’CrCb often termed YUV in digital video.The HVS is less sensitive to changes in color than in changes in luminance.Y'CrCb is used to separate out a luma signal (Y ) that can ′be stored with high resolution or transmitted at high bandwidth, and two chroma components (CB and CR) that can be bandwidth-reduced, sub sampled, compressed, or otherwise treated separately for improved system efficiency.Chroma Sub Sampling24 bits/pixel 16 bits/pixel 12 bits/pixelFig 1.Chroma sub sampling [1,2]Layered StructureSequencePicture / FrameSliceMacro blockBlockFig 2. Layered structure of AVS ChinaLayered Structure Group of Pictures (GOP)SlicePictureMacroblock8 pixels8 pixelsBlockVideo inputChrominance (Cb,Cr )Luminance (Y) Fig 3. Layered structure of AVS China [3]Picture TypesIntra Pictures (I-Pictures)Predicted Pictures (P-Pictures)Interpolated Pictures (B-Pictures)Predicted Picture (P-Picture)Prediction of a Macro block or block in the current picture may be from the most recent reference picture or from the second most recent reference picture. Fig 4. P-Pictures [4]Predicted Picture (P-Picture)In Interlaced Format, prediction of the current field may be made from the four most recent fields. As shown, these fields may be in the current frame, most recent frame or second most recent frame.Fig 5. Interlaced P-Frame prediction [4]Predicted Picture ModesMacroblock modes of P-prediction in AVS video :Mb TypeP_SkipP_16*16P_16*8P_8*16P_8*8 Table 1. Modes of P-picture [5]Interpolated Picture (B-Picture)A Macro block or block in the current picture is predicted by the average of the macro blocks or blocks in the most recent and future P-Pictures that are selected by the motion vector.Fig 6. Interpolated Pictures [4]Interpolated Picture (B-Picture) Fig 7. Interlaced B-Frame prediction [4]Interpolated Picture ModesDirect Mode: Both forward and backward motion vectors of current block are derived from the motion vector of its collocated block .Symmetric Mode: Forward motion vector needs to be transmitted for each partition of current macroblock, while backward motion vector is conducted from the forward motion vector by a symmetric rule .Interpolated Picture Modes Fig 8. Example for symmetric mode [5]Intra Picture(I-Picture)Intra-frame prediction (intra-prediction) uses decoded information in the current frame as the reference of prediction, exploiting statistical spatial dependencies between pixels within a picture. Fig 9. Intra prediction [5]Intra-Prediction Modes8 × 8 Intra-prediction: (a) (b) (c) (d) (e) Fig 10. 8 × 8 Intra-prediction modes for Luminance component [5](a): mode 4 : Down right(b): mode 3 : Down left(c): mode 0 : Vertical(d): mode 1 : Horizontal(e): mode 2 : DCIntra-Prediction Modes4 × 4 Intra- prediction:Fig 11. 4 × 4 Intra-prediction modes for Luminance [5]0 : Down left1: Vertical left2 : Vertical3 : Vertical right4 : Down right5 : Horizontal down6 : Horizontal 7 : Horizontal up8 : DCEncoderFig 12. AVS encoder [4]DecoderFig 13. AVS decoder [4]Results:Profile: JizhunVideo resolution: 704 × 576Frames per second : 30File size: 57.4 MBQP PSNR-Y MSE SSIM MSSSIM 3-SSIM Compression ratio0 61.169 0.05 0.99955 0.9999 0.99995 2.2 : 115 46.614 1.385 0.9875 0.99745 0.99495 6.6 : 131 38.052 9.062 0.9308 0.9778 0.9637 52 : 147 31.864 41.520 0.8340 0.9140 0.8362 315 : 163 24.365 253.23 0.6742 0.5944 0.4715 1435:1References1. http://lea.hamradio.si/~s51kq/subsample.gif : Chroma sub sampling gif.2. http://dougkerr.net/pumpkin/articles/Subsampling.pdf : Chroma sub sampling article.3. http://www-ee.uta.edu/Dip/Courses/EE5359/index.html : UTA Multimedia Processing Website4. http://www.avs.org.cn/reference/AVS%20NAB%20Paper%20Final03.pdf : AVS Document5. L.Yu et al, Overview of AVS-video coding standards, Signal Processing: Image Communication, Vol 24, Issue 4, Special Issue on AVS and its Application, April 2009, Pages 247-262, 6. S.Hu et al, “Efficient Implementation of Interpolation for AVS”, Image and Signal Processing, 2008. Vol 3, pp.133 – 138,May 2008.7. X. Jin et al, “Platform-independent MB-based AVS video standard implementation”, Signal Processing: Image Communication, Vol. 24, Issue 4, pp. 312-323, April 2009.8. W. Gao et al, “Context-based entropy coding in AVS video coding standard”, Signal Processing: Image Communication, Vol. 24, Issue 4, pp. 263-276, April 2009.9. Guo-An Su et al ,“Low-Cost Hardware-Sharing Architecture of Fast 1-D Inverse Transforms for H.264/AVC and AVS Applications”, IEEE Trans. on Circuits and Systems II: Express Briefs, Vol. 55, Issue 12, pp.1249 – 1253, Dec. 2008.References contd..10. W. Gao et al , “A Real-Time Full Architecture for AVS Motion Estimation”, IEEE Trans. on Consumer Electronics, Vol. 53, Issue 4, pp. 1744 –1751, Nov. 2007.11. B. Tang et al,“ AVS Encoder Performance and Complexity Analysis Based on Mobile Video Communication”, WRI International conference on Communications and Mobile Computing, CMC '09, Vol. 3, pp. 102 – 107, . 6-8 Jan. 2009.12. X. Wang and D. Zhao, “Performance comparison of AVS and H.264/AVC video coding standards”, J. Comput. Sci. & Technol., Vol.21, No.3, pp.310-314, May 2006. 13. X.Zhang and L. Yu, “An area-efficient VLSI architecture for AVS intra frame encoder”, Visual Communications and Image Processing 2007, Proc. of SPIE-IS & T Electronic Imaging, SPIE vol. 6508, pp. 650822, Jan. 29, 200714. Special issue on 'AVS and its Applications' Signal Processing: Image Communication, vol. 24, pp. 245-344, April 2009.15. W.Gao, K.N. Ngan and L.Yu “Special issue on AVS and its applications: Guest editorial”, Signal Process:
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