VISUAL COMMUNICATION SYSTEM-TECHNICAL DOCUMENTATION H.239

Transcription

1 H.239 PCS-G60 All PCS-XC1 All PCS-XA55 All PCS-XA80 All PCS-XG55/XG55S All PCS-XG77/XG77S All PCS-XG80/XG80S All PCS-XG100/XG100S All PCS-XL55 All

2 Index Introduction H.239 Supported By The PCS... 4 Presentation function (Presentation role in H.239)... 4 Dual Video function (Live role in H.239)... 4 Dual Video function (Presentation role in H.239) Presentation Function... 5 Transmitting computer images using the Presentation function... 5 Transmission speed of Presentation data Intelligent QoS Support... 6 * In the following text, PCS-XG80 refers to both the PCS-XG80 and PCS-XG80S, and PCS-XG55 refers to both the PCS-XG55 and PCS-XG55S. And, PCS-XG100 refers to both the PCS-XG100 and PCS-XG100S, and PCS-XG77 refers to both the PCS-XG77 and PCS-XG77S Sony Corporation December, 2014/Ver3.2 2

3 Introduction H.239 is the international standard that was ratified by the ITU-T in 2003 to enable videoconference users to deal with one or more appended video data, in addition to ordinary video. The Sony Visual Communication System (hereafter referred to as PCS *1 conforms to the H.239 standard, and thereby promotes the interoperability of videoconferencing endpoints from other manufacturers. H.239 stipulates how to control and manage one or more additional media channels, in addition to the main media channel. The PCS uses the additional media channels via the Presentation function. The Presentation function that the PCS provides can also be used in H.233/H.234/H.235 encrypted communication for when secure videoconferencing is required. This documentation describes the H.239 technology supported by the PCS *2. *1: The supported models are referred to on the front cover. *2: To use this function with the PCS-XG55/XG80/XA55/XA80, the optional Data Solution Software PCSA-DSG80 is separately required Sony Corporation December, 2014/Ver3.2 3

4 1. H.239 Supported By The PCS The PCS can support the Presentation function which conforms to the Presentation role in H.239. Presentation function *2 (Presentation role in H.239) Transmits H.264 or H.263 video signals through the additional media channel *3. When the PCS-XC1/XG100/XG77 transmits H p video signals, the maximum frame rate is 30fps *4. *3 Supported resolution and maximum frame rate are as follows: Model PCS-XC1/XG100/XG77 PCS-XG80/XG55/ XA80/XA55/XL55/G60D/G60DP Resolution and Maximum Frame Rate H.264: 1080p/30fps *4, 720p/30fps, SXGA/30fps, WXGA/30fps, XGA/30fps H.263: XGA/5fps H.264: SXGA/10fps, XGA/30fps, SVGA /30fps, VGA / 30fps H.263: XGA/5fps, SVGA /5fps, VGA /5fps *4 With the PCS-XG77, the optional HD Upgrade Software PCSA-RXG77 is separately required. With the PCS-XC1, the optional HD Upgrade Software PCSA-RXC1 is separately required. This function supports videoconferencing over both IP (H.323 protocol) and ISDN (H.320 protocol) or a combination of the two. For comparison to H.239 that the existing PCS-G70 supported, the PCS-G70's Dual Video function is touched upon below. Dual Video function (Live role in H.239) Transmits and receives H.264, H.263, and H.261 video signals with CIF resolution through the two streams of the additional media channel. This function supports videoconferencing over both IP (H.323 protocol) and ISDN (H.320 protocol) or a combination of the two. Dual Video function (Presentation role in H.239) Transmits and receives H.264, H.263, and H.261 video signals with CIF resolution through the two streams of the additional media channel. This function supports videoconferencing over IP (H.323 protocol) only Sony Corporation December, 2014/Ver3.2 4

5 2. Presentation Function This function conforms to the Presentation role described in ITU-T Recommendation H.239. With this function, the sender terminal can send computer images and camera images simultaneously. The recipient of the data can view the computer images, regardless of whether data solution software is installed into the receiver terminal. In addition, the receiver terminal can only receive video signals with CIF resolution sent by the PCS-G70/G50 or other company's endpoint through the second stream. Using the H.239 standard, the sender terminal firstly exchanges the capacity of all the terminals participating in the conference. Presentation data that conforms to the H.239 standard and camera images can be transmitted at the same time via the Presentation function when the sender terminal determines that the receiver terminal has sufficient capacity for receiving resolution with video mode supported by the PCS. If the sender terminal sends a computer image to a receiver terminal having no capability for receiving H.239, the first stream is automatically changed from a camera image to the computer image. *5 *5: In this case, it is sent with a display pattern selected under "Presentation Screen" in the Video menu for system administrators. If using the PCS-XC1 which does not have this "Presentation Screen" setting, it is sent automatically in the full screen mode as in the case of "Full Screen" selected. Transmitting computer images using the Presentation function There are two ways to send computer images using the Presentation function: Select "Execute" for the "Presentation" from the Tools menu. Press the Presentation button on the remote commander PCS-RFZ1/RF1. Note When presentation data is being sent, the transmission operation will not be available for use by other PCS terminals. Only one terminal participating in the conference can send presentation data at any one time. Transmission speed of Presentation data The transmission speed is determined by the capacity of the H.239 additional media channels of remote terminals. You can select how much of the total bandwidth to use for H.239 presentation data transmissions with a menu. *6 *6: In case of the PCS-XG80/XA80, the maximum transmission speed of the additional media channel is limited to 2Mbps, though that of the main media channel is 10 Mbps. If "2/3" is selected under the "H.239 Ratio" in the menu for system administrators with the PCS-XG80/XA80 set to 10Mbps, the additional media channel exceeds its maximum transmission speed limit (2Mbps). In this instance, a transmission band faster than 2 Mbps is assigned to the main media channel. However, for the terminal that receives the presentation data, the transmission speed of the main media channel does not change (unless it is part of a multi-point connection) Sony Corporation December, 2014/Ver3.2 5

6 3. Intelligent QoS Support The relationship between the Intelligent QoS that the PCS delivers and the Presentation function is shown in the following table. FEC Forward Error Correction ARQ Automatic Repeat request ARC Adaptive Rate Control Audio Video Presentation Not supported IPELA is a trademark of Sony Corporation Sony Corporation December, 2014/Ver3.2 6

7 IPCT001V1