Focus. Video Encoder Optimisation to Enhance Motion Representation in the Compressed-Domain

Transcription

1 Q u a r t e r l y n e w s l e t t e r o f t h e M U S C A D E c o n s o r t i u Special points of interest: The position stateent is on Video Encoder Optiisation to Enhance Motion Representation in the Copressed- Doain Eurosport Broadcasts Live Major Sporting Events in 3D via ASTRA. MUSCADE project results disseinate in SCTE s fourth Balkan Broadband Conference. Holografika participated in the Girls Day 2012, organised in Hungary for the first tie. I n s i d e t h i s i s s u e : Position Stateent Eurosport Broadcasts Live Major Sporting Events in 3D via ASTRA SCTE s 2012 Balkan Broadband Conference and Exhibition MUSCADE at Girls Day DTV-CON, Oct 15-17, Zurich, CH Video Encoder Optiisation to Enhance Motion Representation in the Copressed-Doain Modern video coding technologies have revolutionised the visual edia usage landscape. The prie objective of video coding is to reduce the assive storage capacity and channel bandwidth requireents for storing and transitting digital video in its original for. These technologies have been optiised for classic application scenarios, where copressed video is for huan viewing. However, odern digital edia ecosyste entails ore than just viewing of visual edia. Autoated tools, such as content classification, indexing, adaptation and security tools, ay frequently consue or intercept encoded video. These tools play vital roles to guarantee the sustainability of the odern consuer video services such as digital television and internet video portals. Copyright enforceent and usage tracking tools are classic exaples. Even though video coding do not provide norative support for the content analysis, soe of the copressed doain inforation is useful for such applications. For instance, otion vectors that characterises the teporal scene activity of a video can be used for video segentation and classification applications. Yet the otion vectors available in an encoded video strea ay not be precise enough for certain applications. The reason is that rate-distortion (RD) optiisation technologies incorporated in state-of-the-art video encoders favour less accurate otion vectors to iniise the bit rate. In order to address this issue, video encoder ust explic- w w w. u s c a d e. e u Focus A P R - J U N Position Stateent subitted by Thilini Rajakaruna of University of Surrey itly consider the reliability of content representation while encoding the video. This article presents findings of a recent research study undertaken by University of Surrey to iprove the reliability of otion vectors. In this work, the conventional encoder decision criterion is extended with an objective function for otion vectors, which gives a configurable fraework to anage the accuracy of otion vectors and RD perforance. The proposed configurable encoder odel enhances the reliability of content representation in the copressed video in standard-copliant video coding, while also aintaining video copression efficiency. In encoder optiisation for otion estiation, an objective function for Continued on page 2...

2 P a g e 2 Video Encoder Optiisation to Enhance Motion Representation in the Copressed-Doain continued... Figure 1. Overview of the proposed encoder ipleentation with Rate-Distortion-Motion Description Error (RDE) optiisation Motion Description Error (EMV), is cobined with bit-rate and distortion constraints in a Lagrange [1] optiisation odel. In order to analyse the behaviour of the encoder under different cobinations of optiisation paraeters and otion content levels, a otion calibrated synthetic data set covering different scene coplexities and activity levels was developed as the learning data set. A atheatical odel is developed to represent the sensitivity of EMV to optiisation paraeters. A fully configurable Rate-Distortion- Motion Description Error (RDE) optiisation criterion is proposed using the EMV sensitivity odel, to control the extent of noise in selected otion vectors and copression efficiency. Traditional otion estiation algoriths attept to solve the unconstrained optiisation as given in (1) [2,3] to deterine optiu otion vectors (MV). arg in D RR SAD M (1) where denotes a candidate otion vector within the search region, nuber of bits required to encode a given block using is given by RM() and DSAD() denote the estiated distortion that would result fro using to displace the coding block. λ R is the Lagrange paraeter. It is clear fro (1) that iniising the bit budget to encode otion inforation and residual data and resulting distortion is the prie objective of the traditional otion estiation technologies. In contrast, the proposed encoding technique shown in Figure 1 explicitly incorporates a otion description error as shown in (2). arg in DSAD RRR E E MV (2) where, λ R >0 and λ E >0. A novel objective function, the otion description error, EMV() is forulated, defined for a given candidate otion vector, within the search range. If, = (V X,V Y), EMV(), is given by, E MV V ˆ, Vˆ V, V (3) x where (VX,VY) is the reference MV that represent the expected otion. EMV is odelled independent of the existing rate, distortion objective functions, in order to retain the rate constraint provided by the conventional ratedistortion optiisation. Additionally, this eliinates the inherent liitations of using translational otion odel to represent otion. Figure 2 copares RDE and RD solutions for a set of selected λ R and λ E values. Based on this y The proposed configurable encoder odel enhances the reliability of content representation in the copressed video in standardcopliant video coding, while also aintaining video copression efficiency. x y Continued on page 3...

3 P a g e 3 Video Encoder Optiisation to Enhance Motion Representation in the Copressed-Doain continued... study, a atheatical odel to represent the sensitivity of EMV to λ R and λ E was derived as a function of content properties and the quantisation paraeter used in encoding the video. This odel is used for predicting appropriate values for the Lagrange paraeter for controlling the accuracy of the otion vectors at required level. Table 1 copares the EMV results obtained with three different set of λ R and λ E values. Table also shows the results obtained with RD optiisation perforance as a reference. The results deonstrate that the proposed RDE optiisation criteria can be used to enhance otion representation in copressed-doain without coproising on RD perforance. References [1]. H Everett, Generalized lagrange ultiplier ethod for solving probles of optiu allocation of resources, Operations Research, vol. 11, no. 3, pp , [2]. T. Wiegand, H. Schwarz, A. Joch, F. Kossentini, and G.J. Sullivan, Rate-constrained coder control and coparison of video coding standards, Circuits and Systes for Video Technology, IEEE Transactions on, vol. 13, no. 7, pp , [3]. G. Sullivan, T. Wiegand, and K. Li, Joint odel reference encoding ethods and decoding concealent ethods, Docuent JVT -IO49, San Diego, (a.) (b.) Figure 2. (a) RDE solutions (b) RD solutions for varying control paraeters copared with JM reference Table 1. R-D perforance and Motion Description Error for Selected and settings using RDE optiisation copared with RD optiisation at QP 30 Sequence RD optiisation Bit rate PSNR (kbps) (db) Bit rate (kbps) Rate-Distortion-Motion Description Error (RDE) optiisation PSNR (db) Bit rate (kbps) PSNR (db) Bit rate (kbps) PSNR (db) Soccer Table tennis Coastguard

4 P a g e 4 Eurosport Broadcasts Live Major Sporting Events in 3D via ASTRA 19.2 Degrees East Link: article/ / afrvnkbzagsk.htl On June 05, 2012, SES (Paris:SESG) (LuxX:SESG) announced that Eurosport Group will deliver live 3D broadcasts of two ajor sporting events in the suer across Europe via the ASTRA Satellite Syste. The French Open and the London 2012 Olypic Gaes will be broadcast LIVE on Eurosport 3D fro the ASTRA 19.2 degrees East orbital position. Both events will be transitted via a transponder forerly utilised for analogue transissions in Gerany, and available to illions of European hoes that have their dishes pointed at ASTRA 19.2 degrees East. Making high quality 3D sporting events available to a wider audience and producing copelling 3D content will help spur the growth of the 3D industry. We are proud that SES satellites will be used by our long-standing partners to deliver live action fro the French Open and the London Olypics this suer, said Norbert Hölzle, Senior Vice President Sales Europe at SES. Making high quality 3D sporting events available to a wider audience and producing copelling 3D content will help spur the growth of the 3D industry. Subitted by: Raul GNAGA (SES) SCTE s 2012 Balkan Broadband Conference and Exhibition Link: index.php/events/scte- conferencesexhibitions/details/46- scte-2012-balkan-broadbandconference-and-exhibition SCTE s 2012 Balkan Broadband Conference and Exhibition was held in Belgrade (Serbia) on 29 March 2012, supported by the Cable Operators Association of Serbia. The SCTE s fourth Balkan Broadband Conference offered and opportunity to disseinate the MUSCADE project results for the international participants: investors, operators, technicians, installers, exhibitors coing ainly fro the Western Balkan arket. The Western Balkan arket is one of the ost exciting eerging arkets in Central Europe: ore than 25 illion closelylinked inhabitants in 8 countries. Altogether the event attracted hundreds of visitors coing fro 17 countries. The SCTE s fourth Balkan Broadband Conference offered and opportunity to disseinate the MUSCADE project results Subitted by: Holografika

5 P a g e 5 MUSCADE at Girls Day 2012 Link: default.aspx Holografika participated in the Girls Day 2012, organised in Hungary for the first tie. Aong other technology copanies and universities, Holografika introduced technologies developed during the last couple of years under MUSCADE and the other EU projects, which the copany has actively contributed to. The first Hungarian Girls Day was organized at different telecounication, transport and inforatics copanies in Budapest, Budaőrs, Hatvan and Százhalobatta. Altogether 11 copanies and 7 departents of 2 universities hosted 262 students of 22 high- schools in the first Girls'Day Hungary events! Every organization set up the progra for the Girls Day according to their own possibilities, taking into consideration that the show" needs to catch the interest of the young people. The results speak for theselves. The Woen in Industrial Research, an international conference that preluded the Girl s Day occurred on 25 April, 2012 with ore than 70 attendants. On the other day 11 copanies and 7 faculties of two universities greeted the 262 students fro 22 different secondary schools. Several doestic and international edia reported about the event in alost 80 articles. In only a few weeks, the Facebook page of the event had 168 fans, and ore than people learnt about the progra. The first Girl s Day was not only a huge success, but it also founded a new tradition in Hungary. Aong other technology copanies and universities, Holografika introduced technologies developed during the last couple of years under MUSCADE and the other EU projects Subitted by: Holografika

6 P a g e 6 Announceent: 3DTV-CON, Oct 15-17, Zurich, CH Link: disneyresearch.co/3dtvcon2012/hoe The 3DTV Conference 2012 will be held on October , at ETH Zurich, one of world's top ranked technical universities in one of world's ost beautiful cities. The conference is organized by the Coputer Graphics Lab of ETH and Disney Research Zurich, and sponsored by Disney Research and RealD (Technical Sponsorship by the IEEE Signal Processing Society pending). This is the sixth edition of the conference, held for the first tie in Kos Island, Greece, and then held in Istanbul, Turkey, Potsda, Gerany, Tapere, Finland, and Antalya, Turkey. The 3DTV-CON series of conferences originated fro the FP6 3DTV Network of Excellence and has gotten continuing support fro FP7 projects working in the area of 3D Media. Subitted by: Aljoscha Solic, Disney Research, Zurich The 3DTV Conference 2012 will be held on October , at ETH Zurich, one of world's top ranked technical universities in one of world's ost beautiful cities. Project Manageent Office Astriu Teleco Systes Departent 31 rue des cosonautes Toulouse France Phone: Fax: E-ail: greet.verelst@astriu.eads.net Web: Newsletter Editor University of Surrey MUSCADE: MUltiedia SCAlable 3D for Europe