WO2002080562A1

WO2002080562A1 - Multimedia communication device

Info

Publication number: WO2002080562A1
Application number: PCT/JP2001/005593
Authority: WO
Inventors: Midori Ono
Original assignee: Mitsubishi Denki Kabushiki Kaisha
Priority date: 2001-03-28
Filing date: 2001-06-28
Publication date: 2002-10-10
Also published as: JP2002290973A

Abstract

A multimedia communication device comprises a plurality of coding means (10, 11, 12, 13); transmitting data selection means (14) for selecting one to be transmitted from the coded data (104) produced by the coding means; and data generation means (15) for generating video data (16) that include the selected coded data (104) and coding information (101,102 or 301) on the coded data (104) selected by the data selection means (14).

Description

Description Multimedia communication device Technical field

The present invention relates to a multimedia communication device capable of transmitting and receiving moving images and sounds. Background art

A conventional multimedia communication device exchanges information with a partner terminal device at the start of a call, and the coding type such as video is basically fixed during a call. A method of transmitting and receiving a video coded according to the fixed coding type is adopted. The encoding type defines the internal format of data encoded by, for example, MPEG-4, H261, H'263, etc., and the functions used in encoding. As long as the encoding type is not changed, the transmitting side can freely determine the parameters used for encoding. For example, the transmission period of an intra-frame coded image described in Japanese Patent Application Laid-Open No. 2000-23015 / the quantization characteristic described in Japanese Patent Application Laid-Open No. 8-213139 is The sending terminal can be changed freely.

FIG. 1 is a block diagram showing a configuration of a conventional multimedia communication device described in Japanese Patent Application Laid-Open No. 2000-231354. In FIG. 1, reference numeral 51 denotes a system control unit. Yes, 52 A is the video encoder 1, 52 B is the video encoder 2, 52 C is the video encoder 3, and 53 is the encoded data output selector. , 54 is an input terminal, and 55 is an output terminal.

Next, the operation will be described. The system control unit 51 sets the encoding parameters in the moving image encoding units 1 (52A), 2 (52B), and 3 (52C) that operate in parallel. For example, the moving picture coding unit 1 (52A) is set to perform coding with the period of the intra-frame coded picture (I picture) as 3, and the moving picture coding unit 2 (52B) It is set so that encoding is performed with the period of the intra-frame coded image (I-picture) as 2, and the video encoding unit 3 (52C) performs encoding with the period of the intra-frame coded image (I-picture) as 1. The system control unit 51 is set to perform encoding, and the moving image input from the input terminal 54 is encoded in parallel by each moving image encoding unit, and the encoding from each moving image encoding unit is performed. The optimal coding parameters are determined at certain intervals while evaluating the data representing the obtained image quality, and the encoding is performed so as to select the encoded output data corresponding to the optimal coding parameters. Controls the data output selector 53.

In such a conventional multimedia communication device, the encoding type and the encoding parameters relating to the entire encoding process cannot be changed immediately during a call. For example, if an H324 terminal tries to change the encoding type or the encoding parameters for the entire code during a call, the H324 protocol message is used to obtain the permission of the receiving terminal. After that, it becomes possible to transmit video data in a new encoding type. When returning to the coding type before the change, it is necessary to obtain permission of the partner terminal device using the H245 protocol message in the same manner. For this reason, a time lag occurs between when the protocol message is transmitted from the own terminal device and arrives at the partner terminal device, and when the response is transmitted from the partner terminal device and received by the own terminal device. Normally, video images are transmitted 15 or 10 screens per second, so it was practically impossible to switch the coding method for each screen using a protocol message. On the other hand, a video encoding method generally employs a method of encoding a difference between a previously transmitted image and a current image in order to increase transmission efficiency. Depending on the encoding method, a method for encoding the difference is also used for voice. When coding the difference, the coding efficiency is generally high when the input image has many still parts, but the image quality deteriorates or the coding efficiency deteriorates when the input image has many moving images. And other phenomena. The appearance of these phenomena varies depending on the type of encoding and the parameters at the time of encoding.If the optimal encoding method can be selected at the time of transmission, better image quality in a limited transmission amount range Should be obtained. However, in conventional multimedia communication devices, as described above, it is practically impossible to switch the encoding method for each screen using a protocol message, so that the optimal encoding method for each screen at the time of transmission is not possible. The present invention has been made in order to solve the above-described problem, and has been made by switching the encoding method for each screen using a protocol message. It is another object of the present invention to provide a multimedia communication apparatus that can select an optimal coding method at the time of transmission and can obtain better image quality within a limited transmission amount. . DISCLOSURE OF THE INVENTION

A multimedia communication apparatus according to the present invention includes: a plurality of encoding means for encoding the same moving image; and one of encoded data output from the encoding means selected as a selected encoded data. And transmission data generating means for generating a video data composed of information on the encoding of the selected coded data and the selected coded data. As a result, there is an effect that encoded data can be transmitted to the partner terminal device with optimal image quality at the time of transmission by selectively using a plurality of encoding means at the time of transmission.

In the multimedia communication device according to the present invention, the information on the encoding of the selected encoded data is obtained from encoding method information representing the encoding method and encoded parameter information representing the encoding parameter. The transmission data generation means includes: coding method information indicating the coding method of the selected coded data, coding parameter information indicating the coded parameters, and the selected coded data. And a notifying unit for generating video data composed of the following.

As a result, there is an effect that the encoded data can be transmitted to the partner terminal device with the optimum image quality at the time of transmission.

In the multimedia communication device according to the present invention, the information on the encoding of the selected encoded data is composed of type number information indicating an encoding method and a type number assigned to the encoded parameter. The data generation means includes: a coding method notification means for assigning a type number to the coding method and the coding parameters; and a coding method and coding parameters used for coding the selected coded data. And a type number notifying means for generating video data including type number information indicating the allocated type number and the selected coded data.

As a result, there is an effect that encoded data can be transmitted to the partner terminal device with optimal image quality at the time of transmission while reducing the load during a call.

In the multimedia communication device according to the present invention, the encoding method information and the encoding parameter information are added to the head of the selected encoded data.

As a result, the partner terminal device can decode the encoded data before decoding it. It is possible to obtain information on coding and receive encoded data with optimum image quality.

In the multimedia communication device according to the present invention, the type number information is added to the head of the selected encoded data.

As a result, there is an effect that the partner terminal apparatus can obtain information about the coding before decoding the coded data and receive the coded data with the optimum image quality.

A multimedia communication device according to the present invention includes: a plurality of decoding units for decoding encoded data; and a plurality of decoding units according to information on encoding of video data received from a partner terminal device. And receiving data analysis means for selecting and transmitting the encoded data of the video data to the selected decoding means.

As a result, there is an effect that video data encoded by a plurality of encoding schemes can be decoded in real time at the time of transmission, and can be displayed or reproduced with optimum image quality or sound quality.

In the multimedia communication device according to the present invention, the information on encoding is composed of encoding method information indicating an encoding method and encoding parameter information indicating an encoding parameter, and the reception data analyzing means includes: It comprises a decoding type selection means for selecting a decoding means according to the data encoding method and the encoding parameters.

This has the effect that video data encoded by a plurality of encoding methods can be decoded and displayed in real time.

In the multimedia communication device according to the present invention, the information on encoding includes type number information indicating a type number corresponding to an encoding method and an encoding parameter, and the reception data analyzing means determines that communication has started. Sometimes, the encoding method received from the partner terminal device, the encoding method based on the encoding parameters and the type number Decoding setting means for storing information indicating the correspondence between the expression and the encoding parameter and the type number, and using the type number information of the video data for decoding by collating with the information indicating the correspondence stored in the decoding setting means And decoding number selecting means for selecting decoding means to be decoded.

This has the effect that video data encoded by a plurality of encoding methods can be decoded and displayed in real time with a reduced communication load.

In the multimedia communication device according to the present invention, the video data is composed of encoded data, encoding method information and encoded parameter information added to the head of the encoded data.

As a result, there is an effect that information on encoding can be obtained before decoding the encoded data, and the encoded data can be received with optimal image quality.

In the multimedia communication apparatus according to the present invention, the video data includes encoded data and type number information added to the head of the encoded data.

This has the effect of obtaining information about the coding before decoding the coded data and receiving the coded data with the optimal image quality ^ o Brief description of the drawings

FIG. 1 is a block diagram showing a configuration of a conventional multimedia communication device.

FIG. 2 is a block diagram showing a configuration of the multimedia communication terminal device according to the first embodiment of the present invention.

FIG. 3 shows a video according to the first and third embodiments of the present invention. It is a data block diagram.

FIG. 4 is a block diagram showing a configuration of a multimedia communication terminal device according to Embodiment 2 of the present invention.

FIG. 5 is a configuration diagram of the video data according to the second and fourth embodiments of the present invention.

FIG. 6 is a block diagram showing a configuration of a multimedia communication terminal device according to Embodiment 3 of the present invention.

FIG. 7 is a block diagram showing a configuration of a multimedia communication terminal device according to Embodiment 4 of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, in order to explain this invention in greater detail, the preferred embodiments of the present invention will be described with reference to the accompanying drawings.

Embodiment 1.

FIG. 2 is a block diagram showing a configuration of the multimedia communication terminal device according to the first embodiment of the present invention. In FIG. 2, reference numeral 1 denotes a CCD camera as a video input means for capturing a video and generating a video signal 30, and 10, 11, and 12 encode the video signal 30 and generate encoded data. A video (moving image) encoding means for generating 104a, 104b, and 104c, for example, 10 is an encoding means for encoding by the H263 encoding method; Reference numeral 1 denotes an encoding unit that performs encoding by using the MPEG-4 Visua 1 encoding system, and 12 denotes an encoding unit that performs encoding by using the H 2 62 encoding system. Reference numeral 14 denotes transmission data selection means for selecting the coded data and outputting the selected coded data 104 and the selection result 33, and 15 denotes the selected coded data 1 Transmission data generation means for generating video data 16 based on 0 4 and selection result 3 3, 16 is coded data 104 and selection result 3 3 is a video data generated on the basis of 3; 17 is a data type notifying means constituting the transmission data overnight generating means 15; 2 is a microphone which takes in audio and generates an audio signal 3 2; Reference numeral 13 denotes an audio encoding means to be encoded by the GSM encoding method. Reference numeral 18 denotes a multimedia communication control protocol for notifying the transmission of voice and video with the partner terminal and determining the multiplexing parameters, and 3 is a communication that operates the multimedia communication control protocol 18 to perform communication. A terminal control unit for starting the start procedure, 19 is a media demultiplexer for setting the determined multiplexing parameters. In the first embodiment, the transmission data generating means 15 is constituted by the data type notifying means 17.

FIG. 3 is a diagram showing the configuration of the video server 16. In FIG. 3, 101 is encoding method information (1 byte) indicating the encoding method, and 102 is encoding parameter information (2 knots) indicating the encoding parameter. Yes, 104 is the encoded data (n bytes). The encoding method information 101 and the encoding parameter information 102 become information relating to encoding in the first embodiment and the third embodiment described later.

Encoding method information 101 is a one-byte data, and represents a number indicating a video encoding method. For example, if ITU-TH2661, the number indicating the coding method is 0, if ITU-TH2662, the number indicating the coding method is 1, and if ITU-TH263, the number indicating the coding method is 1. If there is, the number indicating the encoding method is 2.

The code parameter information 102 is a 2-byte data, and represents the coding parameters related to the entire coding process. The content of this parameter depends on the encoding method.For example, in H263, it is determined whether there is a restriction on the length of the motion compensation vector used in differential encoding, and whether or not to use arithmetic encoding. It is indicated by setting the value of a specific bit to 0 or 1. The coded data 104 is an output coded by the coding means 10, 11, and 12 using the coding method indicated by the coding method information 101 and the coding parameter information 102. This is the encoding of the image of one screen of video (n bytes).

Next, the operation will be described.

When the communication line 50 is opened and digital data can be transmitted (arrow (1) in FIG. 2), the terminal control unit 3 operates the multimedia communication control protocol 18 to start a communication start procedure.

The multimedia communication control protocol 18 notifies the transmission of voice and video with the partner terminal, and determines the multiplexing parameters. The determined multiplexing parameters are set in the media multiplexing / demultiplexing unit 19 by the terminal control unit 3 as setting contents (arrow (2) in FIG. 2). At this time, a specific coding method is not determined between the terminal and the partner terminal.

When the multiplexing parameter is set, the media demultiplexer 19 is ready to transmit audio and video. When transmission becomes possible, data is requested from the source of each media (audio and video) (arrow (3) in Fig. 2), and the obtained data is multiplexed and transmitted. In the case of the first embodiment, the source of the audio is the encoding unit 13, and the source of the video is the data type notifying unit 17 of the transmission data generating unit 15.

Hereinafter, the operation in video will be described.

The data type notifying means 17 of the transmitting data generating means 15 requests the data from the transmitting data selecting means 14 in response to the data request from the media multiplexing / demultiplexing 19 (arrow (4) in FIG. 2). ), To obtain the encoded data 104 and the selection result 33. The data type notifying means 17 forms the video data 16 according to the obtained selection result 33 and passes it to the media demultiplexer 19. Here, the composed video data 16 is encoded data as shown in FIG. It represents the encoding method information that indicates the encoding method added before the encoding data (104 bytes (n bytes) and 104), and represents the encoding parameters (1 byte) and the encoding parameters. It consists of encoded parameter overnight information 102 (2 notes). That is, the information indicating the encoding method and the encoding parameters of the received encoded data represents the encoded data is added to the head as information relating to encoding. The encoding method and the encoding parameter represented by the encoding method information 101 and the encoding parameter information 102 are encoding means in which the selected encoding data 10 is encoded. The encoding method and the encoding parameters are added before the encoding data 104 based on the selection result 33 generated by the transmission data selecting means 14.

The transmission data selection means 14 sends data to the encoding means 10, the encoding means 11, and the encoding means 12 in response to a data request from the data type notifying means 17 of the transmission data generating means 15. 'Request (arrow (5) in Figure 2). The transmission data selection means 14 obtains the encoded data 104 a, 104 b, and 104 c from the three coding means 10, 11, and 12. One of the encoded data is selected, and the selected result 33 and the selected encoded data 104 are sent to the data type notifying means 17 of the transmission data generating means 15. Here, the selection result 33 is information for specifying the encoding unit that has generated the selected encoded data 104, and may be, for example, a number representing the encoding unit.

The encoding means 10, 11, and 12 respectively perform video encoding processing on the video signal 30 from the CCD camera 1 to encode data 10 4 a, 10 4 b, and 10 4. c, and generates the encoded data 104a, 104b, and 104b according to the request of the transmission data selection means 14 (arrow (5) in FIG. 2). Pass c to transmission means overnight selection means 14.

As mentioned above, the description so far has been for video. voice Operates as follows.

The audio captured by the microphone 2 is input to the encoding means 13 as an audio signal 32. The encoding means 13 encodes the audio signal 32 according to the GSM method to generate an encoded data 105.

The encoded data 105 is input to the demultiplexer 19. The media demultiplexer 19 multiplexes the input coded audio data 105 and video data 16 and transmits the multiplexed data to the partner terminal device via the communication line 50. As described above, according to the first embodiment, in the multimedia communication terminal device, encoding is performed using different encoding methods and encoding parameters using a plurality of encoding means, and one of the Coded data coded by the coding means is selected, and the coding system and coding parameters of the selected coded data are added to the head of the coded data as coding information. Therefore, it is possible to obtain the effect that the encoded data can be transmitted to the partner terminal device with the optimal image quality at the time of transmission.

Also, according to the first embodiment, in the multimedia communication terminal apparatus, the encoding method information and the encoding parameter information indicating the encoding method and the encoding parameter of the selected encoded data. Is added to the head of the coded data, so that the other terminal device can obtain the information on the coding before decoding the coded data and receive the coded data with the optimum image quality. Fruit is obtained.

In the first embodiment, a case has been described in which three encoding means are used simultaneously for video, but two or four or more encoding means may be used simultaneously. Similar processing is possible. Also, the same processing as video can be performed on audio using a plurality of encoding means. Embodiment 2

FIG. 4 is a block diagram showing a configuration of a multimedia communication terminal device according to Embodiment 2 of the present invention. Since the same reference numerals as those in FIG. 2 indicate the same or corresponding parts, the description is omitted. In FIG. 4, reference numeral 201 denotes an encoding means of encoding means 10, 11, and 12, and a series of encoding parameters and a type number are stored in association with each other, and a multimedia communication control protocol 1 is stored. 8 is a coding method notifying means for transmitting the coding method, the coding parameters and the type number of each coding means to the other terminal device via the communication device 8. Reference numeral 202 denotes a type number notifying means for generating a video data 16 based on the coded data 104 and the selection result 33, and the coding method and code stored in the coding method notifying means 201. The correspondence between the parameterized parameter and the type number is also stored in the type number notification means 202. In the second embodiment, the encoding method notifying means 201 and the type number notifying means 202 constitute the transmission data generating means 15.

FIG. 5 is a diagram showing a configuration of the video data 16 of FIG. In FIG. 5, reference numeral 310 denotes type number information (1 byte), and reference numeral 104 denotes encoded data (n bytes) as in the video data 16 of the first embodiment shown in FIG. is there. The type number information 301 corresponds to the encoding method represented by the encoding method information 101 in FIG. 3 and the encoding parameter information represented by the encoding parameter information 102. This corresponds to encoding information in the second embodiment and the fourth embodiment described later.

The type number information 301 indicates the type number in the correspondence between the encoding method and the encoding parameter stored in the encoding method notifying means 201 and the type number notifying means 202 and the type number. Represents.

Next, the operation will be described.

As described above, in the second embodiment, the transmission data overnight generating means 15 That the type number notifying means 202 and the encoding method notifying means 201, and that the video data 16 consist of the type number information 301 and the encoded data 104 Since it is the same as the first embodiment except for the difference from the first embodiment, the following mainly describes differences in operation based on this difference.

The communication line 50 is opened and transmission of digital data is enabled (arrow (1) in FIG. 4), and the multiplexing parameter is determined. (Arrow (2) in FIG. 4), and audio and video can be transmitted.

In the second embodiment, when transmission becomes possible, the encoding method notification means 201 sends the encoding means 10, 11, and 12 via the multimedia communication control protocol 18. The correspondence between the encoding method and the encoding parameters and the assigned type number is transmitted to the partner terminal device (arrow (6) in FIG. 4).

After the correspondence between the encoding system and the encoding parameters and the assigned type number are transmitted to the other terminal device, the media demultiplexer 19 transmits the data to the transmission source of each media (audio and video). A request is made (arrow (3) in FIG. 4), and the obtained data is multiplexed and transmitted. In the case of the second embodiment, the source of the audio is the encoding unit 13, and the source of the video is the data type notifying unit 17 of the transmission data generating unit 15.

Hereinafter, the operation in video will be described.

The type number notification means 202 of the transmission data generation means 15 requests data from the transmission data selection means 14 in response to a data request from the media multiplexing / demultiplexing device 19 (arrow (4) in FIG. 4). )), And obtain the encoded data 104 and the selection result 33. The type number notifying means 1 構成 composes the video data 16 according to the obtained selection result 33 and passes it to the media demultiplexer 19. Where As shown in FIG. 5, the generated video data 16 includes encoded data 104 and type number information 301 added before the encoded data 104. . That is, type number information 310 representing the encoding method and the type number corresponding to the encoding parameter of the selected encoded data 104 is added to the beginning of the encoded data 104.

The type number represented by the type number information 301 is the type number assigned to the encoding method and the encoding parameter of the encoding means in which the selected encoded data 104 has been encoded, and transmitted. Based on the selection result 33 generated by the data selection means 14, the transmission data selection means 14 added before the encoded data 104 is composed of: and the encoding means 10, 11, and Since the operation of 12 is the same as that of the first embodiment, the description is omitted.

The operation related to audio is also the same as in the first embodiment, and a description thereof will be omitted.

As described above, according to the second embodiment, the encoding method of the selected encoded data and the type number information indicating the type number corresponding to the encoding parameter are used as the information related to the encoding. Since the function is added at the beginning, the same function as in the first embodiment can be realized with a reduced load during a call.

Further, according to the second embodiment, in the multimedia communication terminal apparatus, type number information indicating a type number corresponding to the selected encoding method and the encoding parameter is encoded data. Therefore, the other terminal can obtain the information on the encoding before decoding the encoded data and receive the encoded data with the optimum image quality.

In Embodiment 2, three encoding means are used for video. Although the description has been given of the case of using at the same time, the same processing can be performed by using two encoding units or four or more encoding units at the same time. In addition, the same processing as video can be performed on audio using multiple encoding means.

Embodiment 3.

FIG. 6 is a block diagram showing a configuration of a multimedia communication terminal device according to Embodiment 3 of the present invention. The same reference numerals as those in FIG. 2 indicate the same or corresponding parts, and thus the description thereof will be omitted. In FIG. 6, 3 15 receives video data 16 and sends the encoded data 104 of the video data 16 to the decoding means for the corresponding encoding method and encoding parameter. Decoding type selecting means 314 is a received data analyzing means comprising decoding type selecting means 315. Reference numerals 310, 311 and 312 denote video decoding means for decoding the coded data sent from the decoding type selecting means 315 of the received data analyzing means 314. 0 is a decoding means for decoding in the H266 encoding method, 311 is a decoding means for decoding in the MPEG-4 visual coding method, and 312 is an H266 encoding method. Is decoding means for decoding.

Reference numeral 313 denotes audio decoding means for decoding encoded audio data transmitted from the media demultiplexer 19. Reference numeral 320 denotes a monitor for displaying the decoded video. 3 2 1 is the speed at which the decoded sound is pronounced. In the third embodiment, the received data analysis means 314 comprises decoding type selection means 315.

Next, the operation will be described.

When the communication line 50 is opened and digital data transmission becomes possible (arrow (1) in FIG. 6), the terminal control unit 3 sets the multimedia communication control protocol 1 Operate 8 to start the communication start procedure.

The multimedia communication control protocol 18 notifies voice and video transmission to and from the partner terminal and determines the separation parameters. The determined separation parameters are set to the media multiplex separation 19 by the terminal control unit 3 as setting contents (arrow (2) in FIG. 6). No specific coding scheme is determined with the partner terminal.

The media demultiplexer 19 sets the demultiplexing parameter to be receivable and, when receiving the demultiplexing from the partner terminal via the communication line 50, separates the video or audio demultiplexing. Pass the data to the destination of each media (arrow (3) in Fig. 6). In the case of Embodiment 3 shown in FIG. 6, the audio receiving destination is the decoding means 3 13, and the video receiving destination is the decoding type selecting means 3 15 of the received data analyzing means 3 14. .

The decoding type selection means 3 15 of the received data analysis means 3 14 determines the encoding method and the changing parameter of the video data 16 passed from the media multiplex separation 19 and performs the corresponding decoding. Pass the encoded data 104 to any of the means 310, 311 and 312 (arrow (4) in FIG. 6). Here, the video data 16 passed from the media demultiplexer 19 is, as shown in FIG. 3, the encoded data 104 (n bytes) and the encoded data 104 before the encoded data 104. It consists of coding method information 101 (1 byte) indicating the coding method and coding parameter information 102 (2 bytes) indicating the coding parameter added to. That is, information indicating the received encoding scheme and encoding parameters is added to the beginning of the encoding scheme.

The decoding type selection means 3 15 of the reception data analysis means 3 14 uses the coding method information 101 and the coding parameter information 102 of the video data 16 as information relating to coding, and Decoding means for decoding the encoded data 104 of the video data 16 based on the information on The encoded data 104 is passed to the decoding means. '' Encoding which is selected by decoding type selection means 3 15 of received data analysis means 3 14 among decoding means 3 10, 3 1 1 and 3 1 2 The means decodes the passed encoded data 104 and causes the monitor 320 to display an image.

The above explanation is for the case where the data demultiplexed by the media demultiplexer 19 is a video data — the video 16. However, if the data demultiplexed by the media demultiplexer 19 is the audio data, The sound is sent to the decoding means 3 13, and the decoded sound is emitted through the speaker 3 21.

As described above, according to the third embodiment, the coding method represented by coding method information 101 and coding parameter information 102, which is information related to coding of video data 16 And decoding means for decoding the encoded data of the video data 16 based on the encoding parameters and the encoding parameters, the video data 16 encoded by a plurality of encoding methods are selected. This provides the effect of decoding and displaying in real time.

Further, according to the third embodiment, since the information indicating the received encoding scheme and encoding parameters is added to the head of the encoded data, the encoded data is encoded. It is possible to obtain the information on the encoding before decoding the evening and receive the encoded data with the optimum image quality. Although the description has been given of the case where the means are used at the same time, the same processing can be performed by using two coding means or four or more coding means simultaneously. Similar processing can be performed on audio. Embodiment 4. FIG. 7 is a block diagram showing a configuration of a multimedia communication terminal device according to Embodiment 4 of the present invention. The same reference numerals as those in FIGS. 2 and 6 denote the same or corresponding parts, and a description thereof will be omitted. In Figure 7,

33 0 is a decoding setting means for storing the encoding method and the encoding parameters received from the multimedia communication control protocol 18 and the corresponding type number, and 3 3 1 is decoding setting means 3 3 0 With reference to the correspondence between the encoding method and the encoding parameter stored in the above, and the correspondence between the encoding number and the type number, the encoding method and the decoding means of the encoding parameter corresponding to the type number are selected, and the media demultiplexing is performed.

Decoding number selection means for selecting the encoded data 104 of the video data 16 received from 19 and passing it to the decoding means. The decryption setting means 330 and the decryption number selecting means 331 constitute the reception data analyzing means 314. Next, the operation will be described.

The configuration of the fourth embodiment is the same as that of the third embodiment except that the received data analyzing means 3 14 includes a decoding number selecting means 331 and a decoding setting means 3330. Therefore, the following description focuses on differences in operation due to this difference in configuration.

When the communication line 50 is opened and the transmission of digital data becomes possible (arrow (1) in FIG. 7), the multimedia communication control protocol 18 notifies the other terminal of the transmission of audio and video. Is performed. When the separation parameter is determined and the set content is set to the media multiplex / demultiplex 19 by the terminal control unit 3 (arrow (2) in FIG. 7), the media multiplex / demultiplex 19 becomes a receivable state. Information indicating the correspondence between the encoding method and the encoding parameters transmitted from the partner terminal and the assigned type number is transferred to the multimedia communication control protocol 18 via the media multiplex / demultiplex 19.

Multimedia communication control protocol: Γ 8 is the coding method and coding Information indicating the correspondence between the lame and the assigned type number is passed to the decryption setting means 330 of the reception data analyzing means 314 (arrow (6) in FIG. 6). The decoding setting means 330 stores information indicating the correspondence between the encoding method and the encoding parameter and the assigned type number.

The media multiplex / demultiplex 19, when the information indicating the correspondence between the encoding method and the encoding parameter and the assigned type number is stored in the decoding setting means 330, performs the video or audio decoding. And pass the data to the destination of each media (arrow (3) in Fig. 7).

The decoding number selecting means 3 3 1 of the receiving data overnight analyzing means 3 1 4 sends the type number information 3 0 1 of the video data 16 passed from the media multiplex separation 19 and the decoding setting means 3 3 0 to The stored coding method and the coding parameter are compared with the information indicating the correspondence between the assigned type number and the coding method in which the coded data 104 of the video data 16 is coded. The encoding parameter is determined, and the encoded data 104 is passed to any of the corresponding decoding means 310, 311 and 312 (arrow (4) in FIG. 7). Here, as shown in FIG. 5, the video data 16 passed from the media demultiplexer 19 is composed of encoded data 104 (n bytes) and encoded data 104 It consists of type number information 3 0 1 (1 note) that indicates the type number added to. That is, the type number information 301 representing the received type number is added to the beginning of the encoded data 104.

The decoding type selection means 3 15 of the received data analysis means 3 14 uses the type number information 3 0 1 of the video data 16 as information relating to the encoding, and sends the information relating to this encoding to the decoding setting means 3 3 0. Decoding means for decoding the encoded data 104 of the video data 16 is selected by comparing the stored encoding method and information indicating the correspondence between the encoding parameters and the assigned type numbers, Pass the encoded data 10.4 to the selected decoding means. The operations of the decoding means 310, 311 and 312, and the monitor 320 are the same as those of the third embodiment, and therefore the description thereof is omitted. Also in the fourth embodiment, if the data separated by the media demultiplexer 19 is audio data, the audio data is sent to the decoding means 3 13, and the decoded audio is sent to the speaker 3 2 1 Pronounced through

As described above, in the fourth embodiment, a decoding unit to be used for decoding is selected based on the type number represented by the type number information 301 as information relating to encoding of the video data 16 As a result, video data 16 encoded by a plurality of encoding schemes can be decoded and displayed in real time with a lower communication load than in the third embodiment.

Further, according to the fourth embodiment, since the type number information indicating the type of encoding corresponding to the encoding method and encoding parameters of the received encoded data is added to the beginning of the encoded data, An advantage is obtained in that information on encoding is obtained before decoding encoded data, and encoded data can be received with optimal image quality.

In the fourth embodiment, a case where three decoding means are used simultaneously for video has been described. However, the same processing can be performed even when two decoding means or four or more coding means are used simultaneously. It is. Similar processing can be applied to voice. Industrial applicability

As described above, the multimedia communication device according to the present invention is suitable for obtaining better image quality within a limited transmission amount range in transmitting and receiving moving images and sounds.

Claims

The scope of the claims

1. A plurality of encoding means for encoding the same moving image,

Transmission data selection means for selecting any one of the encoded data output from the encoding means as the selected encoded data;

A multimedia communication device, comprising: transmission data generation means for generating video data including information on encoding of the selected encoded data and the selected encoded data.

2. The information on the encoding of the selected encoded data includes encoding method information indicating the encoding method and encoded parameter information indicating the encoding parameter,

The transmission data generating means is a video data comprising coding method information indicating coding method of the selected coding data and coding parameter information indicating coding parameters, and the selected coding data. 2. The multimedia communication device according to claim 1, further comprising a data type notifying unit that generates the evening.

3. The information on the encoding of the selected encoded data is composed of encoding method and type number information indicating the type number assigned to the encoding parameter.

Transmission data generation means,

An encoding method for allocating a type number to the encoding method and the encoding parameters,

Coding method and coding used for coding the selected coded data 2. The method according to claim 1, further comprising: type number information indicating a type number assigned to each parameter, and type number notifying means for generating video data including the selected coded data. Multimedia through is ί ¾ ο

4. The multimedia communication device according to claim 2, wherein the coding method information and the coding parameter information are added to the head of the selected coding data.

5. The multimedia communication device according to claim 3, wherein the type number information is added to the head of the selected encoded data.

6. A plurality of decoding means for decoding the encoded data,

Received data analysis means for selecting any one of the plurality of decoding means according to the information relating to the encoding of the video data received from the partner terminal device and passing the encoded data of the video data to the selected decoding means When,

A multimedia communication device comprising:

7. The information on the encoding is composed of encoding method information indicating the encoding method and encoding parameter information indicating the encoding parameter.

7. The multimedia communication according to claim 6, wherein the received data analyzing means comprises decoding type selecting means for selecting a decoding means in accordance with a video data encoding method and an encoding parameter. apparatus.

8. Encoding information corresponds to encoding method and encoding parameters Type number information indicating the type number to be

Receiving data analysis means,

Decoding setting means for storing information indicating the correspondence between the coding method, the coding parameter, and the type number based on the coding method, the coding parameter, and the type number received from the partner terminal device at the start of communication. When,

Decoding number selecting means for comparing the type number information of the video data with the information indicating the correspondence stored in the decoding setting means and selecting a decoding means to be used for decoding;

The multimedia communication according to claim 6, characterized by comprising:

9. Claims characterized in that the video data is composed of encoded data, and encoding method information and encoded parameter information added to the beginning of the encoded data. Item 8. The multimedia communication device according to Item 7.

10. The multimedia communication device according to claim 8, wherein the video data includes encoded data and type number information added to the head of the encoded data.