Overview of videoconference clients in EVO

2. Overview of videoconference clients in EVO

3. VIC [ VIdeoConferencing Tool ] • VIC isdefault video clientof EVO system • based on open source project of • OpenMash consortium • the application is written inC++and • OTclprogramming languages • development is focused on following • points: • video codecs (H.261 and H.263) • performance – IPP (Intel • Performance Primitives) Libraries • communication interface for • external applications • user’s comfort and GUI

4. difference framen+1 framen VIC [ H.261 - encoder ] • new encoder is fully compliant with the H.261 standard • old encoder in VIC used only INTRA-mode – compression is • based on reducing of intra frame spatial redundancy • added wasINTER-modewithinter-framemotion estimation • and compensation - differencebetween two subsequent video • framesis encoded -compression is based on reducing of inter • frame temporal redundancy • reduces bitstream (higher compression) - allows to use higher • framerate and quality with the same bitstream

5. MCU Codian - before Polycom VSX7000 - before Polycom VSX7000 - now MCU Codian - now VIC [ H.261 - decoder ] • improvements done on decoder side have influence mainly on • compatibility with H.323 hardware devices • RTP part was changed to avoid artifacts in decoded video from • some H.323 clients and to fix bad positions of macroblocksin • video stream from MCUs and Polycom VSX • bug which causes skipping of the last macroblock in RTP • packet was fixed(avoidsartifacts in decoded video)

6. VIC [ H.263 codec ] • compare to H.261, there are two significant differences: • resolution of video signal (standardized formats up to 16CIF • and custom formats up to 2048x1152) and level of • compression and quality • PRESENT STATUS • currently is implemented only INTRA-frame mode • development is focused on compatibility with H.323 devices, • improvement of codec performance, capturing video with larger • resolutions • Desktop Sharing Mode - VIC is able to capture PC desktop and • send it like H.263 video • one application as video client and desktop sharing client • advantage of existing infrastructure - signal will pass through • network limitations like NAT • higher compression of the signal using H.263 capabilities

7. VIC [ H.263 - Desktop Sharing ] H.261 CIF (352 x 288) H.261 CIF (352 x 288) H.263 XGA (1024 x 768) H.263 VGA (640 x 480)

8. VIC [ Users Comfort ] • the same version forWindows, LinuxandMac OS Xwith the • same features • new GUI– more user friendly, intuitive and easier to • customize. All technical settings have been removed from • the main settings interface window • Speaker Mode- VIC is able to identify and highlight video of • current speaker - information about who is the current • speaker is generated by reflector and carried by specific RTCP • packet (SDES) • newvideo display modeswhich automatically arrange video • windows on the desktop • - all videos in CIF size • - all videos in QCIF size • - only the video of current speaker in CIF size. • - current speaker in CIF size plus all the other videos in QCIF • size

9. VIC [ Users Comfort ] • possibility tosave all settings from GUIincluding position on • the desktop • multiple display supportfor Windows systems - user can • choose display, on which the videos from participants will be • displayed • Still Image Mode –allows transmitting of static picture • instead of video from camera • Minimize Mode–hides small video windows on the main VIC • window, saves space on the desktop • and many others improvements like using FireWire cameras • on MACwithout the IOXpertsdriver and freezing of video

10. RAT [ Robust Audio Tool ] • RAT is default audio client of EVO system • based on open source project of • University College London • the application is written inCand • Tcl/Tkprogramming languages • new audio codec was added(G.722)for • compatibility with H.323 devices • priority of development was tounify • source codefor all supported platforms • (Windows, Linux, Macintosh) – required • new audio interface for MAC OS X • ongoing development is focused on • splittingaudio processingandwindows • managementintotwoseparated threads, • what increaseperformance and stabilityof • the application

11. VIC and RAT onWINDOWS(17 participants) Overview of videoconference clients in EVO

12. VIC on LINUX(17 participants)

13. VIC and RAT on MAC OS X(9 participants) On Mac OS X

14. Communication Interface[ e-Learning scenario ] Teacher Student Student Student Student

15. Communication Interface[ localhost monitoring scenario ] EVO Client RAT VIC ALARM: CPU overloaded Response: decrease framerate, quality, resolution, change video codec, turn off display of big video windows, … Localhost monitoring module LISA

16. PocketVRVS – the mobile solution PocketVRVS – the mobile solution • PocketVRVS isnewVRVS • videoconferencing client developed for • Pocket PC platform • application is written in C++ and Windows • CE API • it supportsH.261 videostandard and • G.711(µ-Law)audiostandard • user can choose CIF sizedstill imageto be • transmitted (JPEG format) • the logic of video encoding wasadaptedto • encoding only still images - the process • was optimized to reach thecompromise • betweenframerate, CPU usageandfast • updateof video on remote clients

17. PocketVRVS – the mobile solution H.323 connection interface PocketVRVS – the mobile solution • utilization ofINTEL Performance Primitivesand Intel compiler • for optimization of application performance (Discrete Cosine • Transform, color model conversions RGB to YUV) • received and decoded isonly video of current speaker– • this functionality is implemented on reflector’s side • PocketVRVSworksinside networks with network address • translation(NAT/NAPT) • newweb based interfacefor Pocket PC clients (designed for • smaller screens) includes full functionality available for • desktop clients(meeting scheduler, booking, …) and also • possibility toconnect H.323 device • installation packageof PocketVRVS application withmulti- • languageOS support isintended directly forPocket PC • platform, desktop computer is not needed

18. PocketVRVS application GUI PocketVRVS – the mobile solution Control Panel Talk, Listen, Send and Receive controls Documentation Download PocketVRVS package Video Screen Remote Video, Own Video in PIP window Booking Session Info Virtual Room, Participant’s name, … Connect to any ongoing meeting Program Menu Connection and Session Settings PocketVRVSweb interface

19. Conclusions Work on new video codecs H.263, H.264 in VIC • higher quality and compression of video signals with higher • resolution Implement software echo canceller into RAT • improvement of thequality of transmittedaudio signals using intelligent algorithm forecho and noise suppression Merging VIC and RAT into one application • efficient processing of incoming video and audio streams by one application (common GUI) + video and audio synchronization Interconnection between VRVS/EVO, RAT and VIC • support of variousvideoconferencing scenarios(education, tutorials, meetings); reaction on alarms Support of live video transmission from PocketVRVS • send real video from cameras for Pocket PC platform Thank you for your attention

20. Additional Slides

21. VIC [ H.261 - encoder] • Block scheme of H.261 encoder with highlighted newly • developed parts • Diamond searching • algorithm • Searching area +/- 7 • SAD sum of absolute • differences Median filter defined in H.261 standard • better compatibility with H.323 devices – solutions on • encoder side: • equal RTP packet size(via MBA stuffing) – avoids packet • reordering and “freezing” of decoded video • fixedH.261 payload RTPheaders

22. VIC [ H.263 codec ] • compare to H.261, there are two significant differences: • Resolution of video signal • standardized picture formats: sub-QCIF (128x96), • QCIF (176x144), CIF (352x288), 4CIF (704x576), • 16CIF (1408x1152) • custom picture formats: resolution up to 2048 x 1152 • Level of compression and quality • Arithmetic Coding instead of VLC - significantly fewer bits produced • Unrestricted Motion Vector Mode - larger vectors and vectors can • point outside the picture • Advanced Prediction Mode - 4 8x8 vectors instead of one • 16x16 vector - results in less blocking artifacts • PB-frames mode - two pictures encoded as one unit • enhanced error resilience capabilities • half pixel precision used for motion compensation + many others

23. VIC [ The Performance ] • IPP(Intel Performance Primitives) libraries were used for • better performance of video codecs in VIC • IPP allows to replace a part of code, which isheavy on • computation–DCT, Motion compensation,… • automatic processor type detection • available forLinuxandWindows • Intelcompileroptimizes compilation for target processor • implementation of IPPfunctions in some H.26x encoder and • decoder parts leads to significant decrease inCPUusage

24. Communication Interface • interface allowing to receive commands from external • applications - like VRVS/EVO client - for interaction with VIC • and RAT during runtime • communication interface uses existing RTCP channel of VIC and RAT applications – doesn’t need additional channel • remote commands are carried by specific Application Defined • (APP) RTCP packets that are understood and subsequently • processed only by VIC and RAT applications and ignored by the • others • useful in conference scenarios, when privileged user can • control audio and video clients of other participants • (e-Learning: teacher vs. students) • VRVS/EVO client can take appropriate action as reaction on • alarm notifications when monitored parameters (system or • network) will go beyond a preset threshold