JPS63178634A - Composite communication system - Google Patents

Abstract

PURPOSE:To transmit information with efficient composite processing by deciding the assignment of the transmission information quantity for each medium to be made composite adaptively in response to the utilizing state of the media according to the procedure with a predetermined priority. CONSTITUTION:A composite control section 1 grasps the utilizing state of each medium, decides the assignment of the transmission information quantity so as to maximize the sum of predetermined quality coefficients to the utilized medium and issues a command to apply coding corresponding thereto to a coding section 3. Each coded information is made composite at a medium composite section 2 and the resulting information is sent through a transmission line 5 via a transmission control section.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical field to which the invention pertains The present invention relates to a composite communication method for multiplexing and communicating a plurality of media using a communication line such as a digital public network.

(2) Conventional technology With the development of communication technology, we believe that high-performance terminals that can combine various media will be used in the future. Communications that combine existing media include videophones that combine video and audio, sketchphones that combine audio and drawing, and conferences that use audio and drawing using previously transmitted still images. There are teleconferencing devices, etc. that perform this function, but in these devices, the allocation of the amount of transmitted information to each medium is fixed.
When the media is not used, it is left empty, or when the media is two sketch phones, etc., a method is used in which the media are allocated at a fixed ratio only when the secondary media is used. Therefore, it is possible to apply this method to a device that selects and combines multiple media from three or more media and performs advanced composite communication.
It is difficult to adaptively allocate the amount of information to be transmitted according to the characteristics of the media, and efficient transmission cannot be performed.

For example, consider a device that combines audio, drawings, videos, and still images. Table 1 shows the relationship between audio encoding methods and bit rates.

Margin table below 1 Audio bit rate There are several encoding methods for one media, and communication with a low bit rate is possible, but if the bit rate is low (the transmission quality will be reduced accordingly). Similarly to audio, video and drawing, which require real-time performance, will suffer from a corresponding drop in quality if the transmission bit rate is limited.

On the other hand, for still images, even if the transmission bit rate is limited, if the transmission time is increased, the quality of the transmitted image can be prevented from deteriorating, but the quality of the service will deteriorate due to the delay in transmission time. Assuming that the amount of transmission information is fixedly allocated to these media as in the past, and a 54 Kbps line is used, the following will be obtained.

Video: 32'Kbps Audio: 16Xbps Drawing: 1 bps Still image: 15Kbps In this state, if the unused media allocation is left open, the line will be wasted. Also, applying a method similar to Sketchpon would be extremely complex, and a new allocation algorithm would be required.

(3) Purpose of the Invention It is an object of the present invention to provide a composite communication system in which a new adaptive amount of transmission information is allocated for decoding a plurality of media.

(4) Structure of the Invention (4-1) Characteristics of the Invention and Differences from the Prior Art The present invention allocates the amount of information to be transmitted to each compounded medium based on a predetermined ranking procedure based on the usage status of the media. It is characterized by being able to be determined adaptively depending on the situation, and there is no such means in the prior art.

(4-2) Embodiment FIG. 1 shows an embodiment in which the present invention is applied to a transmission system in order to explain the present invention. 1 is a decoding control unit, 2 is a media decoding unit, 3 is an encoding unit compatible with each medium, and 4 is an information generation unit for each media (-1, -2, etc. represent each media)
It is. Table 2 shows the relationship between the transmission rate and quality coefficient of each medium used for allocating the amount of transmission information in this embodiment.

Margin Table 2 Below: The operation of this embodiment is such that the decoding control unit l grasps the usage status of each medium and transmits data so that the sum of the quality coefficients given in Table 2 to the media being used is maximized. The information amount allocation is determined and the encoding unit 3 is instructed to perform the corresponding encoding. Each piece of encoded information is decoded by the media decoder 2 and sent to the transmission path 5 through the transmission controller. For example, when a moving image, audio, and still image are combined, the following will occur. Here, S in a still image indicates that image information is inserted into a silent section of audio.

This method has the disadvantage that still images cannot be sent if the conversation continues, but still images can be used repeatedly.

(al) In the case of video, audio, and still images, the entire data must be within 64Kbps, so first set the video to 32Kbps, then set the audio and still images to 32Kbps.
S or 16+(16+s). Here, it is necessary to select between both assignments, but when comparing the quality coefficients of both assignments, the quality coefficient for audio still image is -32 + 3 4 ■ 16 + (16 + S) 4.5,
■ is selected.

fbl In the case of audio, drawing, and still images First, drawing is decided because there is only one option, and then the combination of audio and still images becomes a problem.

Drawing Audio Still image Quality factor ■ 1 +63 + S 9 ■ 1
+47 +(16+S) 10■ 1 +
31 +(32+S) 9.5■ 1 +15
4- (32+S) 8.5 Comparing the above quality coefficients, ■ is selected.

As described above, the amount of transmission information can be allocated according to the quality coefficients in Table 2, but what is important here is the setting of the quality coefficients in Table 2. The bit allocation for each medium changes depending on this value. For example, the quality factor for still images is 4.3.
2.1, ■ (in bl, ■ is selected. When setting this quality coefficient, it is necessary to consider the necessity of each media, transmission quality, and even service quality such as transmission time for still images. be.

A conceivable method for multiplexing and transmitting each media whose assigned bit rate is determined in this way is to assemble a frame as shown in FIG. 2 and display the multiplexing assignment in the header section. Further, the header section may be distributed over a number of frames, or a no-change header may be attached to an unchanged frame, or one header may be attached to several frames. Note that still image information can also be inserted into the silent section by changing the allocation of the header 2. The 48 Kbps audio (+drawing) portion shown in FIG. 2 indicates the allocation of the first medium in use, and the 16 Kbps still image portion shows the allocation of the second medium in use.

Further, "l" in header 1 indicates that the medium exists.

(5) As described in detail, the present invention makes it possible to efficiently combine and transmit multiple media using a simple algorithm. This has the advantage that communication can be realized efficiently.

[Brief explanation of the drawing]

FIG. 1 shows the configuration of an embodiment in which the present invention is applied to a transmission system, and FIG. 2 shows an example of the configuration of a header portion representing a decoding situation used in the present invention. l... Composite control section, 2... Media compounding section, 3
... Encoding section, 4... Information generation section.

Claims (3)

[Claims] (1) Allocating the amount of information to be transmitted to each medium in multimedia communication that combines multiple media and communicates using one or more lines for media including audio, video, drawings, and still images. 1. A composite communication system characterized by comprising a means for determining a ranking according to a media usage situation according to a predetermined ranking procedure, and transmitting using an encoding method corresponding to an instruction from the means. (2) The above allocation procedure is characterized in that a quality coefficient is set in advance for each amount of allocated information for each medium, and the allocation is performed so that the sum of the quality coefficients is maximum for the composite media at that time. A composite communication system according to claim 1. (3) The composite communication system according to claim 1 or 2, characterized in that the allocation status is displayed in a header section of the data assembled into a frame and transmitted.