JP4808170B2 - Network communication terminal device, network communication method, network communication program, and recording medium - Google Patents

Description

  The present invention is connected to a network capable of communication using the Internet protocol, and is based on ITU-T Recommendation T.30. The present invention relates to a network communication terminal device, a network communication method, a network communication program, and a recording medium having a network communication function conforming to the standard 38.

  In recent years, a communication system for communicating image information by a facsimile machine or the like using electronic mail accessed on the Internet has been developed as a communication means with business partners. In communication over the Internet, as a communication standard ITU-T recommendation, a facsimile transmission control procedure for connecting a communication terminal device directly to the Internet and transferring image information between the communication terminal devices is described in T.264. 38 (real-time type) and TIP that stores image information once in a FoIP (Facsimile over IP) gateway device and transmits between the gateway devices using the SMTP protocol or the like. 37 (store and forward type) has been established.

  ITU-T recommendation A communication terminal device having a facsimile communication function compliant with T.38 is described in T.38. It is called 38 terminal device. Transfer of image information is described in T.W. Since it can be performed at the data transfer speed of the packet switching network interposed between the 38 terminal devices, high-speed image information can be exchanged.

  ITU-T recommendation 38, two data transfer modes, a TCP (Transmission Control Protocol) mode and a UDP (User Datagram Protocol) mode, are provided. The 38 terminal device can select one of the operation modes to start communication.

  In the TCP mode, the flow control in the transport layer functions, so that highly reliable data transfer is possible, but there is a disadvantage that the load is increased in the flow control processing and the communication speed becomes slow. In the UDP mode, since flow control in the transport layer is not performed, delivery confirmation, order control, and error retransmission are not performed at all, which is suitable for high-speed processing of image information and the like. On the other hand, there is a disadvantage in that data is lost at the receiving destination and the reliability of data transfer is poor. In the UDP mode, a procedure for recovering an error by transmitting a redundant packet is defined.

In Patent Document 1, T.D. In 38 data transmission, based on the comparison between the reception buffer size declared by the receiver and a specific value preset in the own device, the T.38 data transmission is performed. It is described that the communication speed of 38 data is determined. Patent Document 2 describes that the communication speed is determined at the start of communication based on a specific value set in advance in the communication terminal, and thereafter the speed change during communication is not performed.
JP 2003-87541 A JP 2005-20533 A

  Communication quality in network communication depends on network conditions and receiver performance. In particular, when communicating large data using UDP, the communication quality depends largely on the application because the application determines the communication speed and error recovery parameters (such as the number of redundant portions added).

  An object of the present invention is to improve communication quality by changing a communication speed by feeding back an image data communication result during communication in an application related to image data communication such as IP-FAX. Another object of the present invention is to improve communication quality from the start of communication by using parameters obtained when communication was performed in the past.

In order to achieve the above object, the invention described in claim 1 38, a network communication terminal device having a communication function conforming to 38, an error detection means for detecting an error of received image data by a frame number for each block of the image data, and the frame number detected by the error detection means an error frame number memory means for storing, said error frame number distribution of the stored the frame number in the memory means and the frame number distribution determining means for determining whether the discrete, redundant portions of the image data received Redundant part detecting means for detecting the number of used data, the communication speed of image data, the number of redundant part additions of image data, the number of error frames per block of image data for determining increase / decrease in the number of redundant part additions, and the redundant part a device setting value storing means for storing the usage number of, whether increasing the redundancy portion added the number of said image data Includes a redundant portion added number determination means for constant, the, by the frame number distribution determining means, if the distribution of the error frame number memory means to the stored frame number is determined to be discrete, the partner communication terminal When requesting a change in the communication speed or the redundant part added number , the redundant part added number determining means calculates the number of error frames detected by the error detecting means and the number of error frames stored in the device setting value storage means. If the number of redundant parts detected by the redundant part detection means is compared with the number of redundant parts stored in the device setting value storage means to increase the number of redundant parts added based on the result of comparing the communication speed of the primary portion of the image data to be changed in accordance with an increase and decrease of the redundant portion added number, among the image data defined by the communication protocol Characterized by resetting the communication speed of the image data.

According to a second aspect of the invention, stores a network communication terminal apparatus according to claim 1 Symbol placement, and the destination identifying means for identifying the destination communication terminal, the communication speed of the image data for each of the partner communication terminal the communication Speed communication means, and the communication speed storage means stores a communication speed at the time of successful communication for each counterpart communication terminal, and when receiving a call from the counterpart communication terminal, the counterpart identification means Thus, the destination communication terminal is specified, and image data is communicated at a communication speed at the time of successful communication stored in the communication speed storage means.

The invention according to claim 3 is a T.W. 38. A method of communicating with a network communication terminal device having a communication function conforming to No. 38, wherein an error of a received image data is detected by a frame number for each block of the image data, and detected by the error detection step. An error frame number storing step for storing the frame number, a frame number distribution determining step for determining whether the distribution of the frame numbers stored in the error frame number storing step is discrete, and Step of detecting redundant portion for detecting the number of redundant portions of image data, error in one block of image data for determining communication speed of image data, number of redundant portions added to image data, and increase / decrease in number of redundant portions added a device setting value storage step of storing the number of use of the number and the redundant section frame, before Includes a redundant portion added number determination step of determining whether increasing the redundancy portion added the number of the image data, and by the frame number distribution determination step, the distribution of the error frame number storage step by the stored frame number discrete The error frame detected in the error detection step by the change request step for requesting the partner communication terminal to change the communication speed or the redundant part additional number and the redundant part additional number determining step. The number of error frames stored in the device setting value storage step is compared with the number of redundant portions detected in the redundant portion detection step and the redundant portion stored in the device setting value storage step. When the number of redundant parts added is increased by comparing with the number of uses, the image changes as the number of redundant parts added increases or decreases Based on the result of comparing the communication speed of the primary portion of the over data, characterized in that a communication speed re-setting step of resetting the transmission rate of the image data between the image data defined by the communication protocol.

According to a fourth aspect of the present invention, in the network communication terminal method according to the third aspect , a partner identification step for identifying the partner communication terminal, and a communication speed for storing a communication speed of image data for each partner communication terminal. Storage step, in the communication speed storage step, the communication speed at the time of successful communication is stored for each counterpart communication terminal, and when receiving a call from the counterpart communication terminal, by the counterpart identification step, A communication step of identifying the counterpart communication terminal and communicating image data at a communication speed at the time of successful communication stored in the communication speed storage step.

The invention according to claim 5 is a network communication program for causing a computer to execute the steps according to any one of claims 3 to 4 .

The invention described in claim 6 is a computer-readable recording medium in which the network communication program according to claim 5 is recorded.

  According to the present invention, since the communication speed is changed between the image data defined by the communication protocol, the communication speed can be adjusted to the communication speed suitable for the network state and the performance of the receiving communication terminal, and the communication quality can be improved. .

  Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 is a block diagram showing a configuration of a network communication terminal apparatus for realizing an embodiment of the present invention.

  In FIG. 1, a system control unit 1 is a microcomputer that controls the entire apparatus, and performs control of a predetermined FAX and control of the following embodiment. The scanner 2 reads a document image and extracts image information. The plotter 3 records an image on a recording sheet. The encoding combination unit 4 performs a known encoding method such as the MH method, and compresses the image information to be transmitted by encoding, while reproducing the original image information by combining the received image information. .

  The network control unit 5 is connected to a LAN line. The network control unit 5 transmits packetized data to the network, receives packets from the network, and exchanges data with the network side. The operation display unit 6 displays the operation state of the operation, and the operator performs various operations.

  A storage unit 1 denoted by reference numeral 7 (hereinafter, the first storage unit 7 stores setting values set in the facsimile apparatus by the administrator. In this embodiment, the following settings (a) to (g) are specifically set. Remember the value.

(A) Number of redundant parts used per block of ECM image data for increasing the communication speed (b) Number of error frames per block of ECM image data to increase the number of redundant parts added (c) ECM to increase the number of redundant parts added Number of redundant parts used per block of image data (d) Number of error frames per block of ECM image data to reduce the number of added redundant parts (e) Number of used redundant parts per block of ECM image data to reduce the number of added redundant parts ( f) Image data communication speed (g) Redundant number of image data added

A storage unit 2 (hereinafter referred to as a second storage unit 8) indicated by reference numeral 8 stores communication parameters at the time of successful facsimile reception. Specifically, the following parameters (h) to (j) are stored. FIG. 13 shows data stored in the second storage unit 8.
(H) Source address information (IP address, telephone number)
(I) Communication speed of image data (j) Number of redundant parts added to image data

  Next, an embodiment of the present invention using the above configuration will be described.

(First embodiment)
FIG. 2 is a sequence diagram illustrating a control operation in the network communication terminal device according to the first embodiment. This control system is controlled by the control unit 1.

  The network communication terminal device of this embodiment is an H.264 message sent from the network during reception standby. 323 Monitor the SETUP signal. When the SETUP signal is received, 323 A CallProcessing signal, a Progress signal, an Alert signal, and a Connect signal are transmitted.

  The device setting value “image data communication speed” is read from the storage unit 1. In this embodiment, the device setting value “image data communication speed” is set to 10 Mbps. H. 245 TerminalCapabilitySet signal is transmitted. This signal declares the media communication capability owned by itself. Next, the declaration content of the TerminalCapabilitySet signal is described.

  The attribute parameter of the TerminalCapabilitySet signal is media type = T. 38 UDP, MaxBitRate = 10 Mbps, and the device setting value “image data communication speed” is declared as it is.

  H. When the H.245 TerminalCapabilitySetAck signal is received, H.264 sent from the communication partner terminal is received. H.245 Waiting to receive the OpenLogicalChannel signal. H. When the H.245 OpenLogicalChannel signal is received, the information listed below is extracted from the signal, 245 Send an OpenLogicalChannelAck signal. In this embodiment, right-hand blue information is acquired from the received OpenLogicalChannel signal.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5, MaxBitRate = 10 Mbps.

  By exchanging the above-mentioned OpenLogicalChannel and OpenLogicalChannelAck signals, T.P. 38 UDP channels are connected. Connected T. 38 on the UDP channel. Facsimile communication is performed using the 30 protocol. A DIS signal declaring its own facsimile capability is transmitted, and a DCS signal and a TCF signal are received from the partner communication terminal. When the DCS signal and the TCF signal are received, the CFR signal is transmitted to wait for reception of image data.

  Image data (corresponding to “first block of ECM image data” in FIG. 2) is received. The communication speed of the image data at this time is the received H.264. It becomes 10 Mbps declared in the MaxBitRate of the 245 OpenLogicalChannel signal.

  In this embodiment, image data is communicated by ECM. In the case of ECM, image data is exchanged in units of blocks. One block is composed of 1 to 256 frames, which are packetized for communication.

  In this embodiment, during reception of image data, the received packet is monitored for errors (such as packet loss). If an error is detected, the frame number of the frame in error is stored.

  When the PPS-NULL signal is received, it is determined whether or not the frame number of the detected error frame is discrete. If it is determined that “it is discrete”, A 245 OpenLogicalChannel signal is transmitted to request the other communication terminal to shift down the communication speed of the image data. An example of attribute parameters of the OpenLogicalChannel signal transmitted at this time will be described.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5 (specify the channel number connected in the previous procedure) MaxBitRate = 7.5 Mbps (specify the communication speed 25% down from 10 Mbps).

  H. When the 245 OpenLogicalChannelAck signal is received, the PPR signal is transmitted to request the partner communication terminal to retransmit the image data in error. The retransmitted image data and the PPS-NULL signal are received. At this time, the communication speed of the image data is shifted down to 7.5 Mbps.

  When the MCF signal is transmitted, a second block of image data (corresponding to “ECM image data second block” in FIG. 2) is received. In this embodiment, the received packet is monitored for errors as in the case of receiving the first block. If an error is detected in the second block data, the frame number of the errored frame is stored. When the PPS-NULL signal is received, it is determined whether or not the previously stored frame number is discrete. In FIG. 2, it is determined that the distribution of the frame numbers of the error frames is “not discrete”, and the communication speed of the image data is not changed. An MCF signal is transmitted.

  The image data of the third block (corresponding to “third block of ECM image data” in FIG. 2) is received. The communication speed of the image data at this time remains 7.5 Mbps because no change request is made to the partner communication terminal. A PPS-EOP signal notifying that communication of image data for all pages has been completed is received. An MCF signal is transmitted. When the DCN signal is received, T.P. H.30 has determined that the facsimile procedure has been completed. A 323 ReleaseComplete signal is transmitted to terminate the IP-FAX communication.

  In such an embodiment, by changing the communication speed of the image data determined by the communication protocol, the communication speed can be adjusted to a communication speed suitable for the network state and the performance of the receiving terminal, and the communication quality can be improved.

(Second Embodiment)
FIG. 3 is a sequence diagram showing a control operation in the network communication terminal device of the second embodiment, and FIG. 4 is a flowchart. This control system is controlled by the control unit 1.

  In this embodiment, the network communication terminal apparatus receives the H.264 message sent from the network while waiting for reception. 323 Monitor the SETUP signal. When the SETUP signal is received, 323 A CallProcessing signal, a Progress signal, an Alert signal, and a Connect signal are transmitted.

  Two device setting values are read from the first storage unit 7. The device setting values are the communication speed of image data (in this embodiment, 10 Mbps) and the number of redundant portions added to the image data (in this embodiment, one).

  H. 245 TerminalCapabilitySet signal is transmitted. This signal declares the media communication capability owned by itself. The declaration content of the TerminalCapabilitySet signal is as follows.

  The attribute parameter of the TerminalCapabilitySet signal is media type = T. 38 UDP, MaxBitRate = 10 Mbps (Declare the device setting value “image data communication speed” as it is.) Redundant part addition number = 1 (Declare the device setting value “Redundant part addition number of image data” as it is) .

  H. When the H.245 TerminalCapabilitySetAck signal is received, H.264 sent from the communication partner terminal is received. Wait for reception of the 245 OpenLogicalChannel signal. In this embodiment, information is acquired from the received OpenLogicalChannel signal.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5, MaxBitRate = 10 Mbps, redundant part added number = 1.

  As described above, the OpenLogicalChannel and the OpenLogicalChannelAck signal are exchanged between the communication terminals. 38 UDP channels are connected. Connected T.P. T.38 UDP channel above Facsimile communication is performed using the 30 protocol. A DIS signal declaring its own facsimile capability is transmitted, and a DCS signal and a TCF signal are received from the partner communication terminal. When the DCS signal and the TCF signal are received, the CFR signal is transmitted to wait for reception of image data.

  Image data (corresponding to “ECM image data first block” in FIG. 3) is received. The communication speed of the image data at this time is the received H.264. It becomes 10 Mbps declared in the MaxBitRate of the 245 OpenLogicalChannel signal. In this embodiment, image data is communicated by ECM. In the case of ECM, image data is exchanged in units of blocks. One block is composed of 1 to 256 frames, which are packetized for communication.

  In this embodiment, while the image data is being received, the number of used redundant portions of the received packet is detected and counted. The number of redundant parts used is three.

  When the PPS-NULL signal is received, “determination processing (processing of FIG. 4) for determining whether or not to increase the communication speed” is performed based on the detected number of redundant portions used.

  In the case of this embodiment, there are two redundant parts used in the reception process of the first block of image data and there are three device setting values, so the flowchart branch of FIG. 4 (step S103) is “Yes” side. The determination result is “shift up the communication speed of image data” (step S105).

  If it is determined that the communication speed is shifted up, H. A 245 OpenLogicalChannel signal is transmitted to request the other communication terminal to increase the communication speed of the image data. An attribute parameter example of the OpenLogicalChannel signal transmitted at this time will be described below.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5 (specify the channel number connected in the previous procedure), MaxBitRate = 12.5 Mbps (specify the communication speed up 25% from 10 Mbps) Redundancy added number = 1 It is.

  H. When the H.245 OpenLogicalChannelAck signal is received, the MCF signal is transmitted to prepare for the reception of the next image data. A second block of image data (corresponding to “ECM image data second block” in FIG. 3) is received. The communication speed of the image data at this time has been shifted up to 12.5 Mbps.

  While the image data is being received, the number of used redundant portions of the received packet is detected and counted. In this embodiment, the number of redundant parts used is six. When the PPS-NULL signal is received, a process of determining whether to increase the communication speed (the process of FIG. 4) is performed based on the detected number of redundant parts used. In the case of this embodiment, the number of redundant parts used in the reception process of the second block of image data is 5, and the number of device setting values is 3. Therefore, the determination result in FIG. (Step S104 in FIG. 4). An MCF signal is transmitted to prepare for reception of the next image data.

  The image data of the third block (corresponding to “ECM image data third block” in FIG. 3) is received. The communication speed of the image data at this time remains 12.5 Mbps because no change request is made to the partner communication terminal. A PPS-EOP signal notifying that communication of image data for all pages has been completed is received. An MCF signal is transmitted. When the DCN signal is received, T.P. H.30 has determined that the facsimile procedure has been completed. A 323 ReleaseComplete signal is transmitted to terminate the IP-FAX communication.

  Next, the flowchart of FIG. 4 will be described. FIG. 4 is a flow of determination processing for communication speed shift-up.

  The device setting value “the number of redundant parts used per block of ECM image data whose communication speed is shifted up” is read from the storage unit 1 (step S101). The read device setting value is compared with the number of redundant parts used in one block of the received image data (step S102). As a result of the comparison processing, when the number of redundant parts used is greater than the device setting value (Yes in step S103), it is determined that the communication speed of the image data is not changed (step S104). As a result of the comparison processing, when the number of redundant portions used is smaller than the device setting value (step S103 / No), it is determined to shift up the communication speed of the image data.

  In such an embodiment, the number of used redundant portions of received image data is detected, and when the number of uses is small, the communication speed determined by the communication protocol is changed, so that the communication speed can be changed depending on the state of the network, Communication quality can be improved.

(Third embodiment)
FIGS. 5-8 shows 3rd Embodiment of this invention, FIG. 5 is a sequence diagram which shows the control operation in the network communication terminal device in this embodiment. This control system is controlled by the control unit 1.

  As shown in FIG. 5, the network communication terminal apparatus receives the H.264 message sent from the network while waiting for reception. 323 Monitor the SETUP signal. When the SETUP signal is received, 323 A CallProcessing signal, a Progress signal, an Alert signal, and a Connect signal are transmitted.

  Two device setting values are read from the first storage unit 7. The device setting values are the communication speed of image data (in this embodiment, 10 Mbps) and the number of redundant portions added to the image data (in this embodiment, one).

  H. 245 TerminalCapabilitySet signal is transmitted. This signal declares the media communication capability owned by the device. The declaration content of the TerminalCapabilitySet signal is as follows.

  The attribute parameter of the TerminalCapabilitySet signal is media type = T. 38 UDP, MaxBitRate = 10 Mbps (declares device setting value “image data communication speed” as it is), additional number of redundant portions = 1 (declares device setting value “addition number of redundant portions of image data” as it is) .

  H. When the H.245 TerminalCapabilitySetAck signal is received, H.264 sent from the communication partner terminal is received. Wait for reception of the 245 OpenLogicalChannel signal. In this embodiment, information is acquired from the received OpenLogicalChannel signal.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5, MaxBitRate = 10 Mbps, additional number of redundant parts = 1.

  By exchanging the above-mentioned OpenLogicalChannel and OpenLogicalChannelAck signals, T.P. 38 UDP channels are connected. Connected T. 38 on the UDP channel. Facsimile communication is performed using the 30 protocol. A DIS signal declaring its own facsimile capability is transmitted, and a DCS signal and a TCF signal are received from the partner communication terminal. When a DCS signal and a TCF signal are received, a CFR signal is transmitted to wait for reception of image data.

  Image data (corresponding to “first block of ECM image data” in FIG. 5) is received. The communication speed of image data and the number of redundant parts added at this time are the received H.264 and H.264. It is a value declared in the H.245 OpenLogicalChannel signal (communication speed = 10 Mbps, redundant part added number = 1). In this embodiment, image data is communicated by ECM. In the case of ECM, image data is exchanged in units of blocks. One block is composed of 1 to 256 frames, which are communicated in packets.

  In this embodiment, the following information is detected during reception of image data. That is, information on the number of frames in which an error has occurred (for example, an error in framing in the network due to packet loss, etc.) and the number of used redundant portions of received packets.

  When the PPS-NULL signal is received, a process for determining whether or not to change the redundant part addition number is executed based on the above two detection values (the process of FIG. 6).

  In the case of this embodiment, information detected during reception of image data is as follows. The number of error frames detected upon reception of the first block of ECM image data is nine, and the number of redundant parts used for reception of the first block of ECM image data is eight. The device setting values are as follows. The device setting value “number of error frames per block of ECM image data that increases the number of redundant portions added” is 7, and the device setting value “number of redundant portions used per block of ECM image data that increases the number of redundant portions added” is: The device setting value “number of error frames per block of ECM image data that reduces the number of redundant portions added” is 3, and the device setting value “number of redundant portions used per block of ECM image data that reduces the number of redundant portions added” is set. "Is three.

  From the above six values, the flowchart determination result of FIG. 6 is “increase the redundant part added number” (step S205 of FIG. 6). Hereinafter, the flow of determination processing in FIGS. 6 to 8 will be described.

(1) In step S201 in FIG. 6, “determination processing for determining whether or not to increase the number of additional redundant portions (FIG. 7)” is executed.
(2) In the determination process of FIG. 7, the branch of step S303 is “Yes” because the device setting value is 7 and the number of detected error frames is 9.
(3) In the determination process of FIG. 7, the branch of step S305 is “Yes” because the device setting value is 7 and the number of redundant units used is 7.
(4) In step S306 of FIG. 7, the determination result of “determination process of whether or not to increase the number of redundant additions (step S201 of FIG. 6)” is “increasing the number of redundant part additions (step S306 of FIG. 7)”. Become.
(5) From the determination result of the item (4), the branch of step S202 in FIG. 6 is Yes.
(6) From step S205 in FIG. 6, the determination result of “increasing the number of additional redundant parts” is determined.

  Since the determination result of the “redundant portion addition number change determination process” in FIG. A 245 OpenLogicalChannel signal is transmitted to request the other communication terminal to change the number of redundant portions added to the image data. An attribute parameter example of the OpenLogicalChannel signal transmitted at this time will be described below.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5 (specifies the channel number connected in the previous procedure), MaxBitRate = 10 Mbps, redundant part added number = 2 (declares a value increased by one).

  H. When the 245 OpenLogicalChannelAck signal is received, the PPR signal is transmitted to request the partner communication terminal to retransmit the image data in error. The retransmitted image data and the PPS-NULL signal are received. At this time, the number of redundant portions added to the image data is increased to two.

  When the MCF signal is transmitted, the second block of image data (corresponding to “ECM image data second block” in FIG. 5) is received. In this embodiment, the following information is detected during the reception of the image data in the same manner as when the first block is received. That is, information on the number of frames in which an error has occurred (for example, an error in framing in the network due to packet loss or the like) and the number of used redundant portions of received packets.

  When the PPS-NULL signal is received, “processing for determining whether or not to change the number of added redundant portions (processing in FIG. 6)” is executed based on the above two detection values.

In the case of this embodiment, information detected during reception of image data is as follows.
(1) The number of error frames detected upon reception of the second block of ECM image data is four.
(2) Two redundant parts are used for reception of the second block of ECM image data.

The device settings are as follows.
(3) The device setting value “number of error frames per block of ECM image data to increase the number of redundant portion additions” is seven.
(4) The device setting value “number of redundant parts used per block of ECM image data for increasing the number of redundant parts added” is seven.
(5) The device setting value “number of error frames per block of ECM image data to reduce the number of redundant portions added” is three.
(6) The device setting value “number of redundant parts used per block of ECM image data to reduce the number of redundant parts added” is three.

  From the above six values, the determination result according to the flowchart of FIG. 6 is “do not change the number of added redundant portions” (step S207 in FIG. 6). The flow of determination processing in FIGS. 6, 7, and 8 will be described.

(1) In step S201 of FIG. 6, “determination process for determining whether or not to increase the number of additional redundant parts (FIG. 6)” is executed.
(2) In the determination process of FIG. 7, the branch of step S303 is “No” because the device setting value is seven and the number of detected error frames is four.
(3) In step S307 of FIG. 7, the determination result of “determination process of whether or not to increase the number of redundant additions (step S201 of FIG. 6)” is “do not change the number of redundant part additions (step S307 of FIG. 7)”. It becomes.
(4) From the determination result of item (3) above, the branch in step S202 of FIG.
(5) In step S203 of FIG. 6, the “determination process for determining whether or not to reduce the number of additional redundant parts (FIG. 8)” is executed.
(6) In the determination process of FIG. 8, the branch of step S403 is “No” because the device setting value is three and the number of detected error frames is two.
(7) In step S407 of FIG. 8, the determination result of “determination process of whether or not to reduce the redundant addition number (step S203 of FIG. 6)” is “do not change the redundant part addition number (step S407 of FIG. 8)”. It becomes.
(8) From the determination result of the item (7), the branch of step S204 in FIG.
(9) From step S207 in FIG. 6, a determination result “not to change the number of added redundant parts” is determined.

  Since the determination result of the determination process “change determination process of redundant part addition number (FIG. 6)” is “not changed”, the additional number of redundant parts is not changed. An MCF signal is transmitted. The image data of the third block (corresponding to “third block of ECM image data” in FIG. 5) is received. At this time, since the number of redundant portions added to the image data is not requested to be changed by the counterpart communication terminal, it remains two. A PPS-EOP signal notifying that communication of image data for all pages has been completed is received. An MCF signal is transmitted. When the DCN signal is received, T.P. H.30 has determined that the facsimile procedure has been completed. A 323 ReleaseComplete signal is transmitted to terminate the IP-FAX communication.

  A flowchart of FIG. 6 showing the “redundant portion addition number change determination process” will be described below.

  “Change determination process for determining whether or not to increase the number of added redundant parts (process defined in FIG. 7)” is executed (step S201). When the result of the determination process in step S201 is “increasing the redundant part addition number” (step S202 / Yes), it is determined to increase the redundant part addition number (step S205). When the result of the determination process in step S201 is “Do not change the redundant part added number” (No in step S202), the “change determination process whether to reduce the redundant part added number (the process of FIG. 8)” is performed. Execute (Step S203). When the result of the determination process in step S203 is “reduce redundant part addition number” (step S204 / Yes), it is determined to reduce the redundant part addition number (step S206). If the result of the determination process in step S203 is “do not change redundant part addition number” (step S204 / No), it is determined not to change the redundant part addition number (step S207).

  In the following, the flowchart of FIG. 7 showing the “change determination process for determining whether or not to increase the number of additional redundant parts” will be described.

  Two setting values are read from the storage unit 1 (step S301). The set values are the number of error frames per block of ECM image data that increases the number of added redundant portions and the number of redundant portions used per block of ECM image data that increases the added number of information portions.

  The device setting value read in step S301 “the number of error frames per block of ECM image data that increases the number of added redundant portions” is compared with the number of error frames detected in one block of received ECM image data (step S302). As a result of the comparison process, when the number of detected error frames is smaller than the device setting value (step S303 / No), it is determined not to change the number of redundant part additions (step S307). If the number of error frames detected is greater than the device setting value as a result of the comparison processing in step S302 (step S303 / Yes), the device setting value read in step S301 “ECM image data 1 block for increasing the redundant part added number” The number of redundant parts used around "is compared with the number of redundant parts used in one block of the received ECM image data (step S304).

  As a result of the comparison processing in step S304, when the number of redundant portions used is larger than the device setting value (step S305 / Yes), it is determined to increase the number of redundant portion additions from the next image data communication (step S306). ). As a result of the comparison process in step S304, if the number of redundant parts used is smaller than the device setting value (No in step S305), it is determined that the redundant part added number is not changed (step S307).

  The flowchart of FIG. 8 showing the “determination process for determining whether or not to reduce the additional number of redundant parts” will be described below.

  Two setting values are read from the storage unit 1 (step S401). The setting values to be read are the number of error frames per block of ECM image data that reduces the additional number of redundant portions and the number of redundant portions used per block of ECM image data that decreases the additional number of information portions.

  The device setting value read in S401 “the number of error frames per block of ECM image data that reduces the number of redundant portions added” is compared with the number of error frames detected in one block of received ECM image data (step S402). As a result of the comparison process, when the number of detected error frames is larger than the device setting value (step S403 / No), it is determined not to change the number of added redundant portions (step S407). If the number of error frames detected is smaller than the device setting value as a result of the comparison processing in S402 (Yes in step S403), the device setting value read in step S401 “per one ECM image data to reduce the redundant part added number” The number of redundant parts used ”is compared with the number of redundant parts used in one block of the received ECM image data (step S404).

  As a result of the comparison processing in step S404, if the number of redundant parts used is smaller than the device setting value (step S405 / Yes), it is determined to reduce the number of redundant part additions from the next image data communication (step S406). ). As a result of the comparison process in step S404, if the number of redundant parts used is larger than the device setting value (step S405 / No), it is determined not to change the number of redundant part additions (step S407).

  In such an embodiment, since the number of redundant portions added to the image data defined by the communication protocol is changed, the number can be adjusted to a number suitable for the network state and the performance of the receiving terminal, and communication quality can be improved. it can.

(Fourth embodiment)
FIG. 9 is a sequence diagram showing a control operation in the network communication terminal device of the fourth embodiment, and FIG. 10 is an operation flowchart. This control system is controlled by the control unit 1.

  As shown in FIG. 9, the network communication terminal apparatus receives the H.264 message sent from the network while waiting for reception. 323 Monitor the SETUP signal. When the SETUP signal is received, 323 A CallProcessing signal, a Progress signal, an Alert signal, and a Connect signal are transmitted.

  Two device setting values are read from the first storage unit 7. The device setting values are the communication speed of image data (in this embodiment, 10 Mbps) and the number of redundant portions added to the image data (in this embodiment, one).

  H. 245 TerminalCapabilitySet signal is transmitted. This signal declares the media communication capability owned by the device. The declaration content of the TerminalCapabilitySet signal is as follows.

  The attribute parameter of the TerminalCapabilitySet signal is media type = T. 38 UDP, MaxBitRate = 10 Mbps (declares device setting value “image data communication speed” as it is), additional redundant part number = 1 (declares device setting value “redundant part number of image data” as it is) .

  H. When the H.245 TerminalCapabilitySetAck signal is received, H.264 sent from the communication partner terminal is received. Wait for reception of the 245 OpenLogicalChannel signal. In this embodiment, information is acquired from the received OpenLogicalChannel signal.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5, MaxBitRate = 10 Mbps, redundant part added number = 1.

  By exchanging the above-mentioned OpenLogicalChannel and OpenLogicalChannelAck signals, T.P. 38 UDP channels are connected. Connected T. 38 on the UDP channel. Facsimile communication is performed using the 30 protocol. A DIS signal declaring its own facsimile capability is transmitted, and a DCS signal and a TCF signal are received from the partner communication terminal. When the DCS signal and the TCF signal are received, the CFR signal is transmitted to wait for reception of image data.

  Image data (corresponding to “first block of ECM image data” in FIG. 9) is received. The communication speed of image data and the number of redundant parts added at this time are the received H.264 and H.264. It is a value declared in the H.245 OpenLogicalChannel signal (communication speed = 10 Mbps, redundant part added number = 1). In this embodiment, image data is communicated by ECM. In the case of ECM, image data is exchanged in units of blocks. One block is composed of 1 to 256 frames, which are packetized for communication.

In this embodiment, the following information is detected during reception of image data.
(1) Number of frames with errors (2) Distribution of frame numbers of frames with errors (3) Number of used redundant parts of received packets The information in (1) and (2) is due to packet loss, etc. This includes errors that frame in the network.

  When a PPS-NULL signal is received, a process of determining whether to change the communication speed, change the number of redundant parts added, or change neither, based on the above three detection values (the process of FIG. 10). ).

In the case of this embodiment, information detected during reception of image data is as follows.
(1) The number of error frames detected upon reception of the first block of ECM image data is nine.
(2) The distribution of error frames detected upon reception of the first block of ECM image data is discrete.
(3) Eight redundant parts are used for reception of the first block of ECM image data.

The device settings are as follows.
(4) The device setting value “number of error frames per block of ECM image data to increase the number of redundant portions added” is seven.
(5) The device setting value “number of redundant parts used per block of ECM image data to increase the number of redundant parts added” is seven.
(6) The device setting value “number of error frames per block of ECM image data to reduce the number of redundant portions added” is three.
(7) The device setting value “number of redundant parts used per block of ECM image data to reduce the number of redundant parts added” is three.

  From the above seven values, the determination result by the “communication speed or redundant part addition number change determination process” in FIG. 10 becomes “shift down the communication speed” (step S509 in FIG. 10).

The flow of determination processing in FIG. 10 and FIG. 7 in this embodiment will be described.
(1) Since the distribution of detected error frames is discrete, the branch in step S502 is “discrete”.
(2) The determination process in step S503 is executed.
(3) In the determination process of FIG. 7, the branch of step S303 is “Yes” because the device setting value is 7 and the number of detected error frames is 9.
(4) In the determination process of FIG. 7, the branch of step S305 is “Yes” because the device setting value is 7 and the number of redundant units used is 8.
(5) In step S306 of FIG. 7, the determination result of “determination process of whether or not to increase the number of redundant additions (step S503 of FIG. 10)” is “increasing the number of redundant part additions (step S307 of FIG. 7)”. Become.
(6) From the determination result of item (5) above, the branch of step S504 in FIG. 10 is Yes.
(7) In step S505, the communication speed of the primary part of the image data when the communication speed is shifted down by 25% is calculated. In this embodiment, the communication speed reduced by 25% is 7.5 Mbps, and the communication speed of the primary unit at this time is about ½, 3.7 Mbps.
(8) In step S506, the communication speed of the primary part of the image data when the redundant part added number is increased by one is calculated. In this embodiment, when one is increased, the number is two, and the communication speed of the primary unit at this time is about 3/10, 3.3 Mbps.
9. From the calculation results of item 7 and item 8, the branch of S508 is Yes.
(10) By step S509, the determination result is determined as “communication speed shift down”.

  Since the determination result of the determination process of FIG. A 245OpenLogicalChannel signal is transmitted to request the other communication terminal to change the number of redundant portions added to the image data. An attribute parameter example of the OpenLogicalChannel signal transmitted at this time will be described below.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5 (specify the channel number connected in the previous procedure), MaxBitRate = 7.5 Mbps (declaring the speed down by 25%), redundant part added number = 1 ( (Do not change. Use the same value as the previous declaration value.)

  H. When the 245 OpenLogicalChannelAck signal is received, the PPR signal is transmitted to request the partner communication terminal to retransmit the image data in error. The retransmitted image data and the PPS-NULL signal are received. The communication speed of the image data at this time is shifted down to 7.5 Mbps. The number of redundant parts added is one and has not changed.

When the MCF signal is transmitted, the second block of image data (corresponding to “ECM image data second block” in FIG. 9) is received. In this embodiment, the following information is detected during reception of image data.
(1) Number of frames in which an error has occurred (2) Distribution of frame numbers of frames in error (3) Number of used redundant parts of received packets The information in (1) and (2) above is based on packet loss, etc. This includes errors that frame inside.

  When a PPS-NULL signal is received, a process of determining whether to change the communication speed, change the number of redundant parts added, or change neither, based on the above three detection values (the process of FIG. 10). ).

In the case of this embodiment, information detected during reception of image data is as follows.
(1) The number of error frames detected upon reception of the second block of ECM image data is 0.
(2) In the reception of the second block of ECM image data, there is no error frame, so there is no distribution.
(3) One redundant part is used for reception of the second block of ECM image data.

The device settings are as follows.
(4) The device setting value “number of error frames per block of ECM image data to increase the number of redundant portions added” is seven.
(5) The device setting value “number of redundant parts used per block of ECM image data to increase the number of redundant parts added” is seven.
(6) The device setting value “number of error frames per block of ECM image data to reduce the number of redundant portions added” is three.
(7) The device setting value “number of redundant parts used per block of ECM image data to reduce the number of redundant parts added” is three.

  From the above seven values, the determination result by the “communication speed or redundant part additional number change determination process” in FIG. 10 becomes “not change both the communication speed and the redundant part additional number” (step S511 in FIG. 10).

The flow of the determination process in FIG. 10 and FIG. 7 in this embodiment will be described.
(1) In S501 of FIG. 5-2, it is determined whether the distribution of the detected error frame is “discrete”.
(2) Since no error frame has been detected, the branch of S502 is “not discrete”.
(3) In step S511, the determination result is determined as “not changing both the communication speed and the number of redundant parts added”.

  Since the above determination result (FIG. 10) is “Do not change the communication speed and the number of redundant parts added”, the caller is not requested to change these communication parameters. An MCF signal is transmitted. The image data of the third block (corresponding to “third block of ECM image data” in FIG. 9) is received. The communication speed of the image data at this time is 7.5 Mbps because no change request is made to the partner communication terminal. The number of redundant parts added is also one because no change request is made to the counterpart communication terminal.

  A PPS-EOP signal notifying that communication of image data for all pages has been completed is received. An MCF signal is transmitted. When the DCN signal is received, T.P. H.30 has determined that the facsimile procedure has been completed. A 323 ReleaseComplete signal is transmitted to terminate the IP-FAX communication.

  The “communication speed or redundant part addition number change determination process” in FIG. 10 will be described below.

  It is determined whether or not the distribution of error frames detected by receiving the image data is discrete (step S501). If the determination result in step S501 is “not discrete” (“not discrete” in step S502), it is determined that “the communication speed and the redundant part added number are not changed” (step S511). When the determination result in step S501 is “discrete” (“discrete” in step S502), “determination processing for determining whether or not to add the redundant portion addition number (see FIG. 7 for details of the processing) ”Is executed.

  When the determination result of the determination process in step S503 is “Do not change the redundant part addition number” (“Do not change the redundant part addition number” in step S504), “Do not change both the communication speed and the redundant part addition number”. Is determined (step S511). If the determination result of the determination process in step S503 is “Increase the redundant part addition number” (“Increase the redundant part addition number” in step S504), the process continues to the following process.

  The communication speed of the primary part of the image data when the communication speed is shifted down by 25% is calculated (step S505). When the additional number of redundant parts is increased by 1, the communication speed of the primary part of the image data is calculated (step S506). The communication speed calculated in step S505 is compared with the communication speed calculated in step S506 (step S507).

  As a result of the comparison processing in step S507, when the calculation speed in step S505 (communication speed of the primary part of the image data when the communication speed is shifted down by 25%) is higher (step S508 / Yes), “communication speed” Is shifted down by 25% "(step S509). As a result of the comparison process in step S507, if the calculation speed in step S506 (the communication speed of the primary part of the image data when the number of redundant part additions is increased by 1) is higher (No in step S508), “redundant part addition” “Increase the number by one” is determined (step S510).

  In such an embodiment, the communication speed and error of the image data and the added number of redundant parts are detected, and it is determined whether to change either the communication speed or the added number of redundant parts based on these detection values. Therefore, flexible condition setting can be performed according to the state of the network, and communication quality can be improved.

(Fifth embodiment)
FIG. 11 is a sequence diagram illustrating a control operation in the network communication terminal device according to the fifth embodiment. This control system is controlled by the control unit 1.

  The network communication terminal device receives the H.264 message sent from the network while waiting for reception. 323 Monitor the SETUP signal. When the SETUP signal is received, the following processing is performed.

  H. received. The address information of the caller is extracted from the 323 SETUP signal. The address information is an IP address (example: 133.139.175.221) and a telephone number (example: 033770211).

The “processing for obtaining the communication speed of the image data from the calling source address” in FIG. 12 is executed to obtain the communication speed of the image data in the incoming call. In this embodiment, the caller address information is as follows.
(1) The IP address of the caller is 133.139.175.221.
(2) The caller telephone number is 037770211.
The device settings are as follows.
(3) The device setting value “image data communication speed” is 10 Mbps.

  When the “process for obtaining the communication speed of image data from the caller address” of FIG. 12 is executed with the above three values, a communication speed of 7.5 Mbps is obtained. The processing flow of FIG. 12 in this embodiment will be described.

(1) Using “calling source IP address” 133.139.175.221 as a key, obtain the “image data communication speed” from the storage unit 2 (the storage unit having the data structure of FIG. 6-3) (steps). S601). At this time, the second row in the table of FIG. 13 is hit, and the image data communication speed of 7.5 Mbps is obtained.
(2) In the processing of item (1) above, since the communication speed is obtained, the branch of step S602 is on the Yes side.
(3) Since the determined communication speed is not 0 bps, the branch in step S604 is the No side.
(4) In step S605, the determined communication speed of 7.5 Mbps is determined as the communication speed of the image data in the FAX reception.

  H. 323 A CallProcessing signal, a Progress signal, an Alert signal, and a Connect signal are transmitted. H. 245 TerminalCapabilitySet signal is transmitted. This signal declares the media communication capability owned by the device. The declaration content of the TerminalCapabilitySet signal is as follows.

  The attribute parameter of the TerminalCapabilitySet signal is media type = T. 38 UDP, MaxBitRate = 7.5 Mbps (declaring “the communication speed of image data” obtained in the above process as it is).

  H. When the H.245 TerminalCapabilitySetAck signal is received, H.264 sent from the communication partner terminal is received. Wait for reception of the 245 OpenLogicalChannel signal. In this embodiment, information is acquired from the received OpenLogicalChannel signal.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5, MaxBitRate = 10 Mbps.

  By exchanging the above-mentioned OpenLogicalChannel and OpenLogicalChannelAck signals, T.P. 38 UDP channels are connected. Connected T.P. 38 on the UDP channel. Facsimile communication is performed using the 30 protocol. A DIS signal declaring its own facsimile capability is transmitted, and a DCS signal and a TCF signal are received from the partner communication terminal. When the DCS signal and the TCF signal are received, the CFR signal is transmitted to wait for reception of image data.

  Image data (corresponding to the notation “ECM image data first block” in FIG. 6A) is received. The communication speed of the image data at this time is the received H.264. It becomes the value (7.5 Mbps) declared in the H.245 OpenLogicalChannel signal. According to the first embodiment, the H.264 A 245 OpenLogicalChannel signal is transmitted to change the communication speed of the image data. In this embodiment, it is shifted up to 9.4 Mbps (25% shift up).

  Image data (corresponding to “ECM image data second block” in FIG. 11) is received. The communication speed of this image data is 9.4 Mbps. By receiving the PPS-EOP and the DCN, the T.P. 30 Facsimile communication ends normally. H. By receiving the H.323 ReleaseComplete signal, the H.323 ReleaseComplete signal is received. 323 End the IP-FAX communication.

The following processing is performed at the timing when the IP-FAX communication is completed.
(1) It is determined whether or not the IP-FAX communication has ended normally. In this embodiment, the IP-FAX communication is normally completed.
(2-1) If the IP-FAX communication is normally terminated in the determination processing of item (1) above, the second storage unit 8 (see “Data structure of storage unit 2”) is referred to as the IP- Two pieces of information in FAX communication are stored. The two pieces of information are address information of the caller (in this embodiment, “caller IP address” = 133.139.175.221) and the communication speed of the image data at the end of communication (in this embodiment, “ Image data communication speed "= 9.4 Mbps).

If the caller address information already exists in the second storage unit 8, the “image data communication speed” is overwritten.
(2-2) If the IP-FAX communication is abnormally terminated in the determination process of the item (1), the call is sent from the second storage unit 8 (see “data structure of the storage unit 2” in FIG. 13). Erase information about the original address.

  The “process for obtaining the communication speed of image data from the caller address” in FIG. 12 will be described below.

  Using the caller address as a key, the "image data communication speed" is obtained from the second storage unit 8 (see the data structure in FIG. 13) (step S601). In the process of step S601, when the “image data communication speed” corresponding to the caller address is obtained (step S602 / Yes), the process proceeds to step S604. On the other hand, when the “image data communication speed” corresponding to the caller address is not found in the process of step S601 (step S602 / No), the “image data communication speed” is set to “0 bps” (step S603), the process proceeds to step S604.

  If the obtained “image data communication speed” is not “0 bps” (No in step S604), the obtained “image data communication speed” is set as the image data communication speed in the FAX reception (step S605). On the other hand, when the obtained “communication speed of image data” is “0 bps” (step S604 / Yes), the device setting value “communication speed of image data” is read from the first storage unit 7, and this communication speed is set to the FAX. The communication speed of the image data at reception is set (step S606).

  In such an embodiment, the communication speed at the time of successful communication of the image data and the address of the transmission source are then stored, and the communication of the image data is started at the stored communication speed when receiving from the next transmission source. To do. Therefore, image data can be communicated at a communication speed suitable for each transmission source, and communication quality can be improved.

(Sixth embodiment)
FIG. 14 is a sequence diagram illustrating a control operation in the network communication terminal device according to the sixth embodiment. This control system is controlled by the control unit 1.

  The network communication terminal device receives the H.264 message sent from the network while waiting for reception. 323 Monitor the SETUP signal. When the SETUP signal is received, the following processing is performed.

  H. received. The address information of the caller is extracted from the 323 SETUP signal. The address information is an IP address (for example, 133.139.175.221) and a telephone number (for example, 033770211).

The processing for obtaining the number of redundant portions added to the image data from the caller address shown in FIG. 15 is executed to obtain the number of redundant portions added to the image data in the incoming call. In this embodiment, the caller address information is as follows.
(1) The IP address of the caller is 133.139.175.221.
(2) The caller telephone number is 037770211.
The device settings are as follows.
(3) The device setting value “number of redundant portions added to image data” is one.

  With the above three values, when “the process for obtaining the redundant part addition number of the image data from the caller address” in FIG. 15 is executed, the redundant part addition number “2” is obtained.

  The processing flow of FIG. 15 in this embodiment will be described.

(1) Using “calling source IP address” 133.139.175.221 as a key, obtain “redundant number of redundant part of image data” from the second storage unit 8 (storage unit having the data structure of FIG. 13). (Step S701). As a result, the second row of the table of FIG. 13 is hit, and two redundant portions added to the image data are obtained.
(2) In the processing of item (1) above, since the redundant part added number is obtained, the branch in step S702 is on the Yes side.
(3) Since the obtained redundant part addition number is not −1, the branch of step S704 is the No side.
(4) In step S705, the obtained redundant part addition number 2 is determined as the redundant part addition number of the image data in the FAX reception.

  H. 323 A CallProcessing signal, a Progress signal, an Alert signal, and a Connect signal are transmitted. H. 245 TerminalCapabilitySet signal is transmitted. This signal declares the media communication capability owned by the device. The declaration content of the TerminalCapabilitySet signal is as follows.

  The attribute parameter of the TerminalCapabilitySet signal is media type = T. 38 UDP, redundant part addition number = 2 (declaring “redundant part addition number of image data” obtained in the above process as it is).

  H. When the H.245 TerminalCapabilitySetAck signal is received, H.264 sent from the communication partner terminal is received. Wait for reception of the 245 OpenLogicalChannel signal. In this embodiment, right-hand blue information is acquired from the received OpenLogicalChannel signal.

  The attribute parameter of the OpenLogicalChannel signal is media type = T. 38 UDP, logical channel number = 5, redundant part added number = 2.

  By exchanging the above-mentioned OpenLogicalChannel and OpenLogicalChannelAck signals, T.P. 38 UDP channels are connected. Connected T.P. T.38 UDP channel above Facsimile communication is performed using the 30 protocol. A DIS signal declaring its own facsimile capability is transmitted, and a DCS signal and a TCF signal are received from the partner communication terminal. When the DCS signal and the TCF signal are received, the CFR signal is transmitted to wait for reception of image data.

  Image data (corresponding to “ECM image data first block” in FIG. 14) is received. The number of redundant portions added to the image data at this time is the received H.264. The value (2) declared in the 245 OpenLogicalChannel signal. Similar to the third embodiment, the H.264 standard. 245 An OpenLogicalChannel signal is transmitted to change the number of redundant portions added to the image data. In this embodiment, the number is reduced to one. Image data (corresponding to the notation “ECM image data second block” in FIG. 7A) is received. In this image, the number of redundant portions added to the data is one.

By receiving the PPS-EOP and the DCN, the T.P. 30 Facsimile communication ends normally.
H. By receiving the H.323 ReleaseComplete signal, the H.323 ReleaseComplete signal is received. 323 End the IP-FAX communication. The following processing is performed at the timing when the IP-FAX communication is completed.
(1) It is determined whether or not the IP-FAX communication has ended normally. In this embodiment, the IP-FAX communication is normally completed.
(2-1) If the IP-FAX communication is normally terminated in the determination processing of item (1) above, the second storage unit 8 (see “Data structure of storage unit 2”) is referred to as the IP- Two pieces of information in FAX communication are stored. The two types of information are address information of the caller (in this embodiment, “caller IP address” = 133.139.175.221) and the number of redundant portions added to the image data at the end of communication (in this embodiment) “Number of redundant portions added to image data” = 1). When the information of the caller address already exists in the second storage unit 8, the “number of redundant portions added to the image data” is overwritten.
(2-2) If the IP-FAX communication is abnormally terminated in the determination process of the item (1), the call is sent from the second storage unit 8 (see “data structure of the storage unit 2” in FIG. 13). Erase information about the original address.

  Hereinafter, the “process for obtaining the number of redundant portions added to the image data from the caller address” in FIG. 15 will be described.

  Using the calling source address as a key, the “number of redundant portions added to the image data” is obtained from the second storage unit 8 (see the data structure in FIG. 13) (step S701). In the process of step S701, when the “number of redundant portions of image data added” corresponding to the caller address is found (step S702 / Yes), the process proceeds to step S704. On the other hand, in the process of step S701, when the “image data redundant part added number” corresponding to the caller address is not found (step S702 / No), the “image data redundant part added number” is set to “−. As “1” (step S703), the process proceeds to step S704.

  When the obtained “redundant part addition number of image data” is not “−1” (No in step S704), the obtained “redundant part addition number of image data” is added to the redundant part of the image data in the FAX reception. The number is set (step S705). On the other hand, when the obtained “number of redundant portions added to the image data” is “−1” (step S704 / Yes), the device setting value “number of redundant portions added to the image data” is read from the first storage unit 7. This communication speed is set as the number of redundant portions added to the image data in the FAX reception (step S706).

  In such an embodiment, the additional number of redundant parts at the time of successful communication of image data and the address of the transmission source are stored next, and when the incoming call is received from the next time, the stored additional number of redundant parts is used. Start image data communication. Therefore, image data can be communicated with a redundant portion suitable for each transmission source, and communication quality can be improved.

  The network communication program of the present invention is a program that causes a computer to execute the above steps. The recording medium of the present invention is a recording medium on which the network communication program is recorded so as to be readable by a computer.

It is a block diagram of the network communication terminal device of the embodiment of the present invention. It is a sequence diagram which shows the control action of 1st Embodiment. It is a sequence diagram which shows the control action of 2nd Embodiment. It is a flowchart of a 2nd embodiment. It is a sequence diagram which shows the control action of 3rd Embodiment. It is a 1st flowchart of 3rd Embodiment. It is a 2nd flowchart of 3rd Embodiment. It is a 3rd flowchart of 3rd Embodiment. It is a sequence diagram which shows the control action of 4th Embodiment. It is a flowchart of a 4th embodiment. It is a sequence diagram which shows the control action of 5th Embodiment. It is a 1st flowchart of 5th Embodiment. It is a figure which shows the data structure of 5th Embodiment. It is a sequence diagram which shows the control action of 3rd Embodiment. It is a 1st flowchart of 3rd Embodiment.

Claims (6)

T.A. 38, a network communication terminal device having a communication function conforming to 38,
Error detection means for detecting an error in the received image data by a frame number for each block of the image data;
Error frame number storage means for storing the frame number detected by the error detection means;
Frame number distribution determining means for determining whether or not the distribution of the frame numbers stored in the error frame number storage means is discrete ;
Redundant part detecting means for detecting the number of used redundant parts of received image data ;
Device setting value storage means for storing the communication speed of image data, the number of redundant portions added to image data, the number of error frames per block of image data for determining increase / decrease in the number of redundant portions added, and the number of redundant portions used ,
Redundant part addition number determination means for determining whether or not to increase the redundant part addition number of the image data;
With
When the frame number distribution determining means determines that the distribution of the frame numbers stored in the error frame number storage means is discrete, when requesting the partner communication terminal to change the communication speed or the redundant part added number The redundant part added number determining means compares the number of error frames detected by the error detecting means with the number of error frames stored in the device setting value storage means, and further detected by the redundant part detecting means. When the number of redundant parts added is compared with the number of redundant parts used stored in the device setting value storage means and the number of redundant parts added is increased, the image changes as the number of redundant parts added increases or decreases based on the result of comparing the communication speed of the primary portion of the data, characterized in that resetting the communication speed of the image data between the image data defined by the communication protocol Network communication terminal device. The network communication terminal device according to claim 1,
Partner identification means for identifying the partner communication terminal;
A communication speed storage means for storing the communication speed of the image data for each counterpart communication terminal;
With
The communication speed storage means stores a communication speed at the time of successful communication for each counterpart communication terminal,
When a call is received from the partner communication terminal, the partner identification unit identifies the partner communication terminal and communicates image data at the communication speed at the time of successful communication stored in the communication speed storage unit. A network communication terminal device. T.A. In a method of communicating with a network communication terminal device having a communication function conforming to 38,
An error detection step of detecting an error in the received image data with a frame number for each block of the image data;
An error frame number storage step for storing the frame number detected by the error detection step;
A frame number distribution determination step for determining whether or not the distribution of the frame numbers stored in the error frame number storage step is discrete;
A redundant part detecting step for detecting the number of used redundant parts of the received image data ;
A device setting value storage step for storing the communication speed of image data, the number of redundant portions added to the image data, the number of error frames per block of image data for determining increase / decrease in the number of redundant portions added, and the number of redundant portions used; ,
A redundant part addition number determination step for determining whether or not to increase the redundant part addition number of the image data;
With
When the frame number distribution determining step determines that the distribution of the frame numbers stored in the error frame number storing step is discrete, the partner communication terminal is requested to change the communication speed or the redundant part added number. The number of error frames detected in the error detection step and the number of error frames stored in the device setting value storage step are compared by the change request step and the redundant part addition number determination step, and the redundant portion detection is further performed. When the number of redundant parts detected in the step is compared with the number of redundant parts used stored in the device setting value storing step, and the redundant part additional number is increased, the redundant part additional number is increased or decreased. based on the result of comparing the communication speed of the primary portion of the image data to be accompanied changes, image data defined by the communication protocol In network communication method is characterized in that a communication speed re-setting step of resetting the transmission rate of the image data. The network communication terminal method according to claim 3, wherein
A partner identification step for identifying the partner communication terminal;
A communication speed storing step for storing the communication speed of the image data for each of the counterpart communication terminals;
With
In the communication speed storage step, the communication speed at the time of successful communication is stored for each counterpart communication terminal,
When a call is received from the partner communication terminal, the partner communication terminal is identified by the partner identification step, and image data is communicated at the communication speed at the time of successful communication stored in the communication speed storage step. A network communication method comprising: a communication step.   The network communication program for making a computer perform each step in any one of Claims 3-4.   A computer-readable recording medium on which the network communication program according to claim 5 is recorded.

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