AVS CHINA, IMPLEMENTATION & PERFORMANCE ANALYSIS OF VIDEO PROFILES

Vamsi Krishna VeguntaUniversity of Texas, Arlington

Vamsikrishna.vegunta@mavs.uta.edu

Interim 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 Sampling

24 bits/pixel 16 bits/pixel 12 bits/pixel

Fig 1.Chroma sub sampling [1,2]

Layered Structure

Sequence

Picture / Frame

Slice

Macro block

Block

Fig 2. Layered structure of AVS China

Layered Structure

Group of Pictures (GOP)

Slice

Picture

Macroblock

8 pixels

8 pixels

BlockVideo input

Chrominance (Cb,Cr )

Luminance (Y)

Fig 3. Layered structure of AVS China [3]

Picture Types

Intra 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 Type

P_SkipP_16*16

P_16*8

P_8*16

P_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 : DC

Intra-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 : DC

Encoder

Fig 12. AVS encoder [4]

Decoder

Fig 13. AVS decoder [4]

Results: Profile: Jizhun Video resolution: 704 × 576 Frames per second : 30 File size: 57.4 MB

QP PSNR-Y MSE SSIM MSSSIM 3-SSIM Compression ratio

0 61.169 0.05 0.99955 0.9999 0.99995 2.2 : 1

15 46.614 1.385 0.9875 0.99745 0.99495 6.6 : 1

31 38.052 9.062 0.9308 0.9778 0.9637 52 : 1

47 31.864 41.520 0.8340 0.9140 0.8362 315 : 1

63 24.365 253.23 0.6742 0.5944 0.4715 1435:1

References1. 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, 2007

14. 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: Image Commun, vol. 24, Issue 4, pp 245-344, April 2009.

16. R. Schafer and T. Sikora, “Digital video coding standards and their role in video communications”, Proc. of the IEEE, vol. 83, pp. 907-924, June 1995.

17. M.Liu and Z.Wei “A fast mode decision algorithm for intra prediction in AVS-M video coding” Vol 1, International Conference on Wavelet Analysis and Pattern Recognition apos;07, Issue 2-4, pp.326 –331, Nov. 2007.