White Paper on Video Wall Display Technology in Videoconferencing HUAWEI TECHNOLOGIES CO., LTD. Issue 01. Date

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1 White Paper on Video Wall Display Technology in Videoconferencing Issue 01 Date HUAWEI TECHNOLOGIES CO., LTD.

2 2012. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd. Trademarks and Permissions and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders. Notice The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied. The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute a warranty of any kind, express or implied. Huawei Technologies Co., Ltd. Address: Website: Huawei Industrial Base Bantian, Longgang Shenzhen People's Republic of China support@huawei.com i

3 Contents Contents 1 Important Concepts Videoconferencing Technology Video Wall Video Wall Display Solutions External Video Wall Server Embedded in an MCU Internal Video Wall Server Embedded in an MCU Huawei ViewPoint Introduction Features Video Wall Display Solution for MCU Cascading... 8 ii

4 1 Important Concepts 1 Important Concepts 1.1 Videoconferencing Technology Videoconferencing is an interactive multimedia communication service based on telecommunication networks. It integrates audio, video and data services. By real-time transmission of audio, video and data, the videoconferencing technology provides a virtual conference room for people in different locations. Conferences held using the videoconferencing technology are free from time and location limitations. The videoconferencing technology reduces traveling costs and improves communication efficiency. It is becoming more and more popular in various industries. Figure 1-1 shows the networking for videoconferencing. Figure 1-1 Networking for videoconferencing Bearer network Terminal Terminal Terminal A basic videoconferencing system as shown in Figure 1-1 consists of an MCU, multiple videoconferencing terminals and telecommunication network. 1.2 Video Wall A video wall is an ultra-large display screen that consists of multiple display units such as PDPs, LCDs and DLPs. The video wall is a system for displaying videos, images and text. As shown in Figure 1-2 and Figure 1-3, a 3 x 3 video wall consists of nine display units. 1

5 1 Important Concepts Figure 1-2 Video wall consisting of nine display units (1) Figure 1-3 Video wall consisting of nine display units (2) Video walls usually work with video matrix switchers and video splitters. Working with a video splitter, a video wall can display one channel of video with the video split and evenly displayed on each display unit. It can also display different channels of video on different display units. Moreover, it can display one channel of video on some display units and other channels of video on the other display units. A large video wall is very impressive and superior. Convenient and easy-to-use in real-time monitoring, displaying multiple channels of video on a video wall is widely used in dispatching centers, monitoring centers, media control centers and trading centers. 2

6 2 Video Wall Display Solutions 2 Video Wall Display Solutions A video wall display solution is provided to display videos of conference sites at the same time, improve users' videoconferencing experiences, and provide monitoring and scheduling functions. In a videoconference, people watch the videos on video terminals. Each terminal receives only one channel of video stream from the MCU, so each terminal displays videos of one conference site. To meet the requirement of watching videos of different conference sites at the same time, traditionally the continuous presence technology is adopted. The MCU compresses the videos of various conference sites into one video and then transmit it to the terminals. After compression, the video definition decreases and the compressed video can be clearly displayed on only one display unit. Because the video and audio streams of all conference sites are transmitted to the MCU, a good solution is to decode the video and audio streams and transmit them to the video wall directly. This is the mainstream video wall display solution. To implement this solution, an external video wall server or internal video wall server embedded in the MCU is required. 2.1 External Video Wall Server Embedded in an MCU Figure 2-1 shows the networking in the solution involving an external video wall server embedded in an MCU. 3

7 2 Video Wall Display Solutions Figure 2-1 Networking in the solution involving an external video wall server embedded in an MCU External video wall Packet capture TV wall server DVI, VGA or YPbPr Multiple flat-panel TVs The videoconferencing systems using IP networks are becoming popular. Such systems can intercept the packets sent from conference sites to the MCU by exchanging IP packets and mapping the switches' ports. The external video wall server decodes the videos of conference sites and then transmits them to the video wall. Therefore, multi-channel videos can be displayed on the video wall at the same time. The solution involving an external video wall server embedded in an MCU has the following strengths: When an MCU cannot transmit video streams to the video wall, the external video wall server can output the videos on the video wall. An external video wall server is compatible with videoconferencing systems produced by most manufacturers. An external video wall server can be located at any place where the data packets can be intercepted. It can be located meters away from the router by extending the network cable. The solution involving an external TV wall server embedded in an MCU also has the following weaknesses: An external video wall server works on an IP network only. It cannot intercept packets transmitted over E1, 4E1 and ISDN lines. An external video wall server cannot decode or output videos of encrypted conferences. An external video wall may not achieve the optimal display effect because it may be incompatible with the MCU in video decoding capability and anti-packet-loss mechanism. 4

8 2 Video Wall Display Solutions Two sets of software are needed. One for conference management and the other for video wall management. The external video wall server can decode either HD videos or SD videos. It is difficult to output HD and SD videos at the same time. The packet capture rate is limited by the server's performance and the number of its ports. The maximum packet capture rate is 100 Mbit/s. An external video wall server provides 8 ports or 16 ports. 2.2 Internal Video Wall Server Embedded in an MCU Figure 2-2 shows the networking in the solution involving an internal video wall server embedded in an MCU. Figure 2-2 Networking in the solution involving an internal video wall server embedded in an MCU Internal video wall DVI, VGA or YPbPr Multiple flatpanel TVs The video streams of all conference sites are transmitted to the MCU and the MCU decodes and then outputs the streams directly to a video wall using an output port. Therefore, multi-channel videos can be displayed on the video wall at the same time. The solution involving an internal video wall server embedded in an MCU has the following strengths: Videoconferencing terminals are compatible with the MCU in decoding capability and anti-packet-loss mechanism. The internal video call server can decode videos of encrypted conferences and videoconferencing terminals can achieve an optimal video display effect. Compatible with all types of lines, an internal video wall server can decode and output videos as long as the conferences can be accessed. 5

9 2 Video Wall Display Solutions An internal video wall can output videos in the formats supported by the MCU, such as 1080p, 720p, 1080i, 4CIF and CIF. Videoconferencing terminals can output HD and SD videos at the same time. The solution involving an internal video wall server embedded in an MCU has the following weaknesses: Decoding capability of the MCU must be improved and video output ports must be added to the MCU. Extended HD video cables must be used if the MCU is far away from the video wall control room. Therefore, the cost is increased. 6

10 3 Huawei ViewPoint Huawei ViewPoint Introduction Based on the advanced daughter board extension technology, Huawei ViewPoint8650 (VP8650 for short) supports HD (up to 1080p) and SD (up to 4CIF) by adding daughter boards to the MCU. Using VP8650, Huawei provides a powerful HD video wall solution for the electricity industry, armed forces, police stations, governments and operators. Figure 3-1 shows the networking of Huawei VP8650. Figure 3-1 Networking of Huawei VP8650 Video TV wall VP9035 VP8069 VP8039 VP Mbit/s H Mbit/s 4CIF H.263 4CIF 2 Mbit/s H p 2 Mbit/s H p 3.2 Features The solution involving an internal video wall server embedded in an MCU is implemented using video wall decoding boards and output daughter boards. The solution has the following characteristics: Independent hardware decoding boards are adopted, 1080p and SEC are supported, and an optimal display effect can be achieved. 7

11 3 Huawei ViewPoint 8650 Huawei VP8650 supports HD and SD video walls. Both HD and SD videos can be displayed on video walls at the same time. The MCU can process continuous presence and video wall streams at the same time. The solution supports display of continuous presence and presentation on a video wall. It can broadcast panes in continuous presence in turn. The solution can output videos in groups. Videos of the same conference site can be output in groups. Management software is used to remotely control the pan, tilt, zoom (PTZ) functions of the cameras in the conference sites, facilitating conference monitoring and control. Specifications of an SD video wall are as follows: SD CVBS port supporting PAL and NTSC systems. Decoding of HD video streams (up to 1080p) and output of 4CIF video streams (that is, decoding HD video streams and outputting SD video streams on the video wall). Configuration of the number of output channels (up to 48 CVBS channels). Specifications of an HD video wall are as follows: HD DVI-I port supporting DVI, VGA or YPbPr. Output of HD (up to 1080p) video streams. Configuration of the number of output channels (up to 32 channels of HD videos). 3.3 Video Wall Display Solution for MCU Cascading Limited by the MCU capacity and the bandwidth of the network, videoconferencing systems of large-sized enterprises usually adopt a large-scale networking involving MCU cascading. Only one channel of audio-visual streams can be transmitted between the upper-level MCU and the lower-level MCU, so the video wall connected to the upper-level MCU can display videos of only one conference site. Huawei VP8650 innovatively adopts the multi-channel cascading technology. Using the multi-channel cascading technology, videos of a maximum of 32 conference sites can be transmitted to the upper-level MCU and displayed on the video wall connected to the upper-level MCU. Therefore, the problem that the video wall connected to the upper-level MCU can display videos of one conference site only is solved. Figure 3-2 shows the networking in the solution involving multi-channel cascading. 8

12 3 Huawei ViewPoint 8650 Figure 3-2 Networking in the solution involving multi-channel cascading Upper-level MCU Video wall Video wall server IP network Conference site 1 Video wall Lower-level MCU Video wall server Cascading channel 1 Cascading channel 2 Cascading channel 3 Additionally, the number of video walls connected to the lower-level MCU can be increased. Using the multi-channel cascading technology, videos of lower-level conference sites and upper-level conference sites can be displayed on a local video wall free from the limitations of the upper-level MCU. Therefore, the video wall display solution for MCU cascading is applicable for a large-scale networking. 9