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Contact UsOverview of ARIB Technical Report (TR-B34)
1. Overview
| TR Number | ARIB TR-B34 |
|---|---|
| Technical Report Name | Guidelines on Quality Control in Real-time Video Transmission over IP Networks for Program Production and News Gathering |
| Enactment Date | 12.06.2011 |
| General Description | In late years it increases to transmit the video such as program materials or information camera pictures in real time using IP network. The IP network has unique problems such as packet loss or packet jitter so that it is necessary for securing picture quality to take appropriate measures after having understood a characteristic of the IP video transmission. This technical report explains unique problems of the real time video transmission system with best-effort type IP network service and countermeasures to cope with the problem. A method to utilize the countermeasures effectively is also included in the report. |
Keywords
| Keyword | Description |
|---|---|
| IP video transmission | Video data is converted to IP (Internet Protocol) packet, and is transmitted. |
| Transmission quality | In this technical report, the video transmission quality with IP video transmission is evaluated by three elements -- delay, availability and picture quality (encoding). |
| Delay | The delay in the IP video transmission system includes the processing delay due to encoding in a codec, packeting, and error correction and the transmission delay of the IP network. The transmission delay of the IP network includes a physical propagation delay depending on a transmission distance and a delay by the disposal of passage devices such as network equipment. |
| Packet loss | It is a phenomenon admitted in a reception side that occurs when the equipment of the latter half detecting an error discards packets if data error occurs in the part of packets in the IP network. Also it occurs when network equipment discards packets not to exceed a processing capacity, a band limit of the interface, and a logical band limit. It becomes the factor of the deterioration (block noise, an omission and break of the frame, freeze, decode stop) of the video quality. |
| Packet jitter | It is a phenomenon that occurs when arriving time interval of a packet at the reception side is different from sending time interval at the transmission side. The outbreak source of packet jitter is processing time (delay) of a passage device including network equipment. It greatly varies by specifications, characteristics, and operational environment of the equipment. It becomes a video quality deterioration factor (video clock precision deteriorates mainly) in the IP video transmission. |
| FEC(Forward Error Correction) | Forward error correction processing. It is one of the methods of packet loss compensation. At the transmission side, the FEC packet that corresponds to the sequence of the media packet is generated. And at the reception side, transmitted media packet and FEC packet are reconstituted according to original packet sequence to supplement the packet that lacked. |
| ARQ(Automatic Repeat reQuest) | The automatic repeat request method. It is one of the methods of packet loss compensation. The packet loss is detected through cooperation with the transmission side and the reception side and a request is made to retransmit it at the transmission side. |
2. Amendment History
| Ver. | Amendment or Enactment Date | Amendment summary |
|---|---|---|
| 1.0 | 12.06.2011 | Enactment |
