JPH025660A - System for controlling simultaneous transfer of video packet and sound packet - Google Patents

Abstract

PURPOSE:To correct the time lag between sound and video by controlling the queueing and preferential output of sound and picture information by means of buffers after identifying the simultaneousness between a sound packet and video packet. CONSTITUTION:An identifier controlling section 7 supplies an identifier code which is unequivocally identifiable with a certain fixed period, namely, a nonoverlapping identifier code to a picture information packet and sound information packet assembling sections 5 and 6 in accordance with a picture or sound packet assembling period. The packet sent from a communication network 9 to its own station is received by a receiving section 10 and a picture packet disintegrating section 11 disintegrates a picture packet into separate pieces of control and picture information and a sound packet into separate pieces of sound and control information. A sound and picture preference controlling section 13 controls the delay and preference of the packets and simultaneousness of sound and picture information from sent sound and picture information and their control information and identifier codes.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a video packet/audio packet synchronous transfer control system, and in particular, the present invention relates to a video packet/audio packet synchronous transfer control method, and in particular, in order to synchronously transfer information such as video and audio, packet order is controlled within a communication network. The present invention relates to a communication control method for controlling a communication device and performing appointment control using a communication device.

[Conventional technology]

Hitherto, a high-speed digital time division multiplexing system for simultaneously transmitting audio information and video information has been proposed (see the specification and drawings of Japanese Patent Application No. 1982-26G-913). There also exists a communication system that transfers information PK such as video information and audio using a circuit switching method.

However, a method for transferring both video information and audio information in packets does not yet exist, and no materials have been found that have proposed such a method.

In a system in which video information and audio information are transferred by circuit switching, the transfer delay is constant because the circuit is switched, and there is no difference in the delay between video information and information such as audio that can be perceived by humans. Therefore, there were no particular problems.

[Problem to be solved by the invention]

In this way, when video and audio information are transferred synchronously using packets, synchronization is difficult because the arrival times of the video and audio packets at each location within the communication network are different, and the delay times between the two are different. Met. Therefore, a synchronous transfer method for both packets does not yet exist.

The purpose of the present invention is to solve such conventional problems, correct the time lag between video information and audio information, and synchronize the transfer of both buckets 1 to 1 to make it possible to harmonize images and audio. An object of the present invention is to provide a video packet audio packet rotation control method.

[Means to solve the problem]

-1-2 To achieve the objective 1 The video packet audio packet synchronous transfer control system of the present invention assembles video information and audio information accompanying the video information into video packets and audio packets at 991 positions, respectively, and transfers them. In the communication terminal device that is the packet transmission source, the packet control information of the video packet and audio packet is stored in a portion of the communication terminal device that is the packet transmission source.

An identifier code for mutually identifying the video information of the video packet and the audio information accompanying the video information,
The identifier code is set in each of the video packet and the audio packet and transmitted, and the destination communication terminal device of the packet uses the above identifier code to distinguish between the video packet and the audio packet with the audio information attached to the video information of the video packet. One of the packets is made to wait, and the order of video packets that arrive out of order and the order of audio packets are controlled so as to minimize the difference in delay within the transmission path between the two. , is characterized by synchronizing and outputting video information and audio information. In addition, video information and audio information accompanying the video information are assembled into video packets and audio packets in blocks, respectively, and transmitted from a source communication terminal device to a destination communication terminal device via a switching device and a relay device. In a network system, a communication terminal device that is a packet source sends buckets 1 to L of video packets and audio packets.
An identifier code for mutually identifying the video information of the video packet and the audio information accompanying the video information is set in each of the video packet and the audio packet in the portion storing the control information, and then transmitted. However, in the relay device and the switching device, the difference in delay within the communication network between the video packet received using the identifier code and the audio packet of audio information accompanying the video information of the video packet is determined. Another feature is that one of the packets is placed on standby and the order of video packets and audio packets that arrive out of order are controlled and transmitted so as to minimize the number of packets.

[Operation] In the present invention, in order to absorb the difference in delay between video packets and audio packets within the communication network, identifiers are set in the headers of video packets and audio packets, and the order of the video packets and the audio In addition to controlling the order of packets, if one of the packets arrives late, the packet that arrived first is made to wait for a certain amount of time.
Alternatively, buckets 1~ that arrived late are given priority for transfer.

In this way, the difference in arrival time between video packets ~ and audio packets within the communication network is absorbed, and the destination communication terminal device determines the above identifier, and the video packets and audio packets with the same identifier are output synchronously.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to one drawing.

FIG. 1 is a block diagram of a transmitting section and a receiving section showing an embodiment of the present invention, in which (a) is the transmitting section and (b) is the receiving section.

In FIG. 1 (, l), 1 is an image information input unit for inputting image information, 2 is an audio information input unit for manually inputting audio information, and 3 is an image input unit for converting image information into digital code. 4 is an audio information digital encoding unit for converting audio information into digital codes; 5 is an image information packet assembling unit that assembles digital codes of image information into buckets 1 to 1; 6 is an audio information digital encoding unit; an audio information packet assembling unit that assembles codes into packets; 7 an identifier control unit for setting a common identifier for both image packets and audio packets when assembling image and audio information packets; 8 accesses a communication network; 9 is a communication network.

When an image is input from the 1-image information input section 1.

It is immediately converted into an analog electrical signal and sent to the image information digital encoding section 3. The image information digital encoding section 3 converts the analog electrical signal into a digital electrical signal and sends it to the one image information packet assembly section 5.

On the other hand, when the voice is manually input to the voice information input section 2, it is immediately converted into an analog electrical signal and sent to the voice information digital encoding section 4. The audio information digital encoder 4 converts the analog electrical signal into a digital electrical signal and sends it to the audio information packet assembler 6.

The identifier control unit 7 generates an identifier code that can be uniquely identified within a certain period of time, that is, a non-overlapping identifier code, according to the cycle in which image packets or audio packets are assembled, and combines the image information packet assembling unit 5 and the audio The information is supplied to the information packet assembling section 6.

Image information packet assembly unit 5 and audio information packet assembly unit 6
That is, the identifier code from the identifier control unit 7 is stored in the image packet and audio packet control units, respectively, and the image packet and audio packet are assembled. These packets are assembled.

Each is sent to the transmitter 8. The transmitter 8 sends these image packets and audio packets to the communication network 9 using the access control function to the communication network 9 .

The control units for video packets and audio packets mutually identify the source and destination addresses, an identifier for identifying whether it is video information or audio information, and audio information accompanying video information. an identifier code for (e.g.
It consists of the same code indicating that it is an audio packet of audio information accompanying the video information of a certain video packet.

Audio packets are transferred at a speed of, for example, 64 KHz, while video packets are transferred at a speed of, for example, 1.5 MI (z), so there is a difference in transmission time within one communication network.
At the destination communication terminal device or relay device within the communication network, a delay difference occurs between the video packet and the accompanying audio packet.

In FIG. 1(b), reference numeral 10 indicates a reception unit that receives image packet and audio packet information from the communication network 9, and reference numeral 11 extracts an identifier code from the image packet and separates the image information section and control section of the packet. An image packet decomposition unit 12 extracts an identifier code from an audio packet and separates the audio information part and the control part of the packet.
are the information part and control part of each packet, the order of the packets from the identifier code, and the audio image order control part which performs control to ensure simultaneity. This audio image order control section 1
Specifically, in No. 3, the order of packets that arrive out of order is controlled, and control such as waiting is performed based on the identifier code, thereby ensuring the simultaneity of audio and images. 14 is a buffer memory that stores information for waiting. Reference numeral 15 is an image information decoding section that converts a digital electrical signal of an image into an analog electrical signal, and reference numeral 16 is an audio information decoding section that converts a digital electrical signal of an audio signal into an analog electrical signal. 17 is an image information output unit that outputs image information;
8 is an audio information output unit that outputs audio information.

Packets addressed to the local station sent from the communication network 9 are received by the receiving unit 10. The packet received by the receiving unit 10 is separated into an image packet and an audio packet, and
The signals are sent to an image packet decomposition unit 11 and an audio packet decomposition unit 12, respectively. The image packet decomposition unit 11 decomposes the image packet into control information and image information. The above-mentioned identifier code is included in the control information. Also,
The audio packet decomposition unit 12 decomposes the audio packet into audio information and control information in the same manner.

This information is sent to the audio image order control section 13.

The audio image order control unit 13 uses the received audio information 1 image information, control information of these information, and identifier code,
Control packet delay, order, and simultaneity of audio and video information.

Below, regarding the simultaneity of audio and images related to the present invention,
Explain in detail.

A common identifier code is added to the audio information and image information of the sent packet, and these identifier codes indicate the simultaneity of the audio information and image information, so they should originally be output at the same time. It is something. The audio image order control section 13 searches for image information having an identifier code that matches the identifier code of the audio information, and if there is a match, simultaneously sends the image information to the image/audio decoding sections 15 and 16, respectively.

If only one piece of information exists and the other does not exist, the receiver waits for the other piece of information to arrive for a period allowed.

During this time, the information is held and stored in the buffer memory 14.

If the other information does not arrive even after the period allowed by the receiving section has elapsed, it is treated as missing information, and the existing information is sent to the decoding section 15 or 16. Further, the audio image order control unit 13 controls the order between audio information and image information sent in packets, and outputs audio and images in the correct sequence.

The decoding units 15, 1.6 convert the digital audio and image electrical signals into analog signals, and output the signals to the respective output units 17.
Send on 18th. Image output section 17 and audio output section 18
outputs images and sounds using these electrical signals.

FIG. 2 is a configuration diagram when the present invention is applied to a relay system within a communication network.

In FIG. 2, 19 is a relay system receiving section, 20 is an image bucket 1 to processing section, 21 is an audio packet processing section, 22
2 is a packet order control unit, 23 is a buffer memory, and 24 is a relay system transmission unit.

Since the relay system has both a receiving section and a transmitting section, it is equipped with both the transmitting section and the receiving section shown in FIGS. 1(a) and 1(b).

Audio and video packets within the communication network are received by the relay system receiver 19, identified and sent to the respective packet processors 20.21. Each packet processing unit 20.2
1 executes processing such as determining the next route to be output from the information of the control unit (routing processing, etc.). The processed packets are each sent to the packet order control unit 22.

The packet order control unit 22 determines the order relationship between image information based on the identifier code, and performs control such as queuing, sending out with priority, etc. In other words, if only one of the images or audio exists, the information of the existing one is waited for, and the information of the other is waited for. Also, if the information is sent first as missing information, then the packet of information of the other arrives. Sometimes, priority is given to sending. Similar processing is also performed between audio information. Furthermore, the audio 1 whose identifier code of the audio information and the identifier code of the image information match
When the image packet has not arrived at the relay system, the other packet is made to wait in a buffer memory 23 for a waiting time allowed by the relay system, thereby correcting the time lag between audio and image packets in the relay system. Thereafter, each packet is transmitted from the relay system transmitter 24.

In this way, in this embodiment, by providing the order control unit, the time lag between the audio packet and the image packet is corrected, so that the audio information and the image information can be output while maintaining the simultaneity.

〔Effect of the invention〕

As explained above, according to the present invention, the simultaneity of audio packets and image packets is identified, and the buffering and priority output of audio/image information is controlled, so that RF audio and image It is possible to correct time lag and provide a communication service that harmonizes audio and images.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a transmitting section and a receiving section showing one embodiment of the present invention, and FIG. 2 is a block diagram of the case where the present invention is applied to a relay system within a communication network. 1: Image information input section, 2: Audio information input section, 3: Image information digital code section, 4: Audio information digital code section,
5: Image information bucket 1 to assembly section, 6: Audio information packet assembly section, 7: Identifier control section, 8: Transmission section, 9: Communication network,
10: Receiving unit, 11: Image packet decomposition unit, 12: Audio packet decomposition unit, 13: Audio image order control unit, 14: Buffer memory, 15: Image information decoding unit, 16: Audio information decoding unit, 17: Image Information output unit, 18: audio information output unit, 21: audio packet processing unit, 22: packet order control unit, 23: buffer memory, 24: relay system transmission unit. Patent applicant Nippon Telegraph and Telephone Corporation

Claims (2)

[Claims] (1) In a communication terminal device that assembles video information and audio information accompanying the video information into video packets and audio packets in blocks and transfers them, the communication terminal device that is the packet transmission source is configured to assemble the video packets and audio packets into the video packets and audio packets. In the portion storing the packet control information, an identifier code for mutually identifying the video information of the video packet and the audio information accompanying the video information is set in each of the video packet and the audio packet. The communication terminal device that is the destination of the packet uses the above identifier code to detect the difference in delay within the transmission path between the video packet and the audio packet of the audio information accompanying the video information of the video packet. The video information and the audio information are synchronized by placing one of the packets on standby and controlling the order of the video packets that arrive out of order and the order of the audio packets so that the number of packets is minimized. A video packet audio packet synchronous transfer control method characterized by outputting video packets and audio packets. (2) Video information and audio information accompanying the video information are assembled into video packets and audio packets in blocks, respectively, and transferred from the source communication terminal device to the destination communication terminal device via the switching device and relay device. In a communication network system, a communication terminal device that is a packet transmission source mutually identifies the video information of the video packet and the audio information accompanying the video information in the part that stores the packet control information of the video packet and audio packet. An identifier code for identifying the video packet and the audio packet is set and transmitted to each of the video packet and the audio packet, and the relay device and the switching device use the identifier code to identify the received video packet and the video information of the video packet. In order to minimize the difference in delay within the communication network between audio packets of accompanying audio information, one of the packets is placed on hold, and the order and audio of video packets that arrive out of order are minimized. A video packet/audio packet synchronous transfer control method characterized by controlling the order of packets and transmitting them.