JP2001268114A - Internet facsimile equipment, control method therefor, internet facsimile transmitter and internet facsimile receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide Internet facsimile equipment, a control method therefor, an Internet facsimile transmitter and an Internet facsimile receiver, with which the trouble of UDP mode can be reduced. SOLUTION: When buffer overflow is detected on the side of receiving, after that, latency is inserted between UDP packets for carrying picture information on the side of transmitting. Thus, there is an effect that smooth picture information transmission is enabled while utilizing the UDP mode by controlling timing to send out the picture information on the transmitting side so as not to generate the buffer overflow on the receiving side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Internet facsimile apparatus, a control method thereof, an Internet facsimile transmitting apparatus and an Internet facsimile receiving apparatus.

[0002]

2. Description of the Related Art In recent years, ITU-T Recommendation T. An Internet facsimile apparatus having a communication function and performing real-time communication using the Internet is being provided. This Recommendation T. In the 38 communication function, the communication mode is TCP (Transmission Control).
l Protocol (TCP / IP (Int
(Ethernet Protocol) mode)
UDP (User Datagram Protocol)
1) Two communication modes of a mode (also referred to as a UDP / IP mode) are provided.

[0003] In general, Recommendation T. 38 Internet facsimile machine with communication function, TCP mode and UDP
It is configured to be able to select one of the modes.

[0004]

Among the above communication modes, in the former TCP mode, since flow control by TCP is performed, there is an advantage that communication reliability is high. There is a disadvantage that the communication delay time is long because of the overhead.

On the other hand, in the latter UDP mode, there is no flow control, so there is an advantage that the communication delay time is shorter than in the TCP mode. On the other hand, when a buffer overflow on the receiving side occurs, for example, However, there is a problem that it cannot be dealt with. In the facsimile apparatus, the decoding process for error checking on the receiving side has a relatively large processing amount, so that the data processing speed is slower than that on the transmitting side, and as a result, a buffer overflow may occur. .

An object of the present invention is to provide an Internet facsimile apparatus, a control method thereof, an Internet facsimile transmitting apparatus, and an Internet facsimile receiving apparatus which can reduce such a problem in the UDP mode.

[0007]

SUMMARY OF THE INVENTION The present invention is based on ITU-T Recommendation T.30. In an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, a buffer overflow detecting means for detecting a buffer overflow of a partner terminal during image information transmission in a UDP mode; When a buffer overflow is detected, a picture information transmitting means for inserting a predetermined delay time into a transmission interval of each packet carrying picture information is provided.

Further, according to ITU-T Recommendation T. In an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, a buffer overflow detecting means for detecting a buffer overflow of a partner terminal during image information transmission in a UDP mode; When the buffer overflow is detected, a predetermined delay time is inserted into the transmission interval of each packet carrying image information, and when the buffer overflow detection means detects the buffer overflow of the partner terminal even after the delay time is inserted, Each time, there is provided an image information transmitting means for increasing the delay time.

Further, according to ITU-T Recommendation T. An Internet facsimile apparatus having a communication function and performing real-time communication using the Internet is described in Recommendation T.38.
38 When a call signal is received, an incoming call response means for sending a response signal containing information indicating the reception buffer size of the own terminal to the calling side, and a buffer overflow of the partner terminal is detected during image information transmission in the UDP mode. Buffer overflow detecting means, and when the buffer overflow detecting means detects a buffer overflow of the partner terminal, the data accumulation value of one or more packets carrying image information is included in the response signal received from the partner terminal. When the size exceeds the buffer size for use, a picture information transmitting means for inserting a predetermined delay time before transmitting the next packet carrying the picture information is provided.

[0010] Also, according to ITU-T Recommendation T. An Internet facsimile apparatus having a communication function and performing real-time communication using the Internet is described in Recommendation T.38.
38 When a call signal is received, an incoming call response means for sending a response signal containing information indicating the reception buffer size of the own terminal to the calling side, and a buffer overflow of the partner terminal is detected during image information transmission in the UDP mode. Buffer overflow detecting means, and when the buffer overflow detecting means detects a buffer overflow of the partner terminal, the data accumulation value of one or more packets carrying image information is included in the response signal received from the partner terminal. If the buffer size exceeds the buffer size, a predetermined delay time is inserted before the next packet carrying image information is transmitted, and after the delay time is inserted, the buffer overflow detection means detects the buffer overflow of the partner terminal. Each time, an image that increases the delay time Those having a transmission means.

[0011] When the buffer overflow detecting means receives the signal RTN or the signal PPR from the partner terminal, it determines that the partner terminal has caused a buffer overflow.

Also, according to ITU-T Recommendation T. 38 In a control method of an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, when a buffer overflow of a partner terminal is detected during image information transmission in the UDP mode, the transmission interval of each packet carrying image information is set to , A predetermined delay time is inserted.

Further, according to ITU-T Recommendation T. 38 In a control method of an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, when a buffer overflow of a partner terminal is detected during image information transmission in the UDP mode, the transmission interval of each packet carrying image information is set to A predetermined delay time is inserted, and when the buffer overflow of the partner terminal is detected even after the insertion of the delay time, the delay time is increased each time.

Further, according to ITU-T Recommendation T. In a control method of an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, the method described in Recommendation T.38. 38, when a call signal is received, a response signal including information for notifying the receiving buffer size of the own terminal is sent to the calling side, and while image information is being transmitted in the UDP mode, a buffer overflow of the partner terminal is detected. If the data accumulation value of one or more packets carrying information exceeds the size of the receiving buffer included in the response signal received from the partner terminal, a predetermined number of packets are transmitted until the next packet carrying image information is transmitted. Is inserted.

Further, according to ITU-T Recommendation T. In a control method of an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, the method described in Recommendation T.38. 38, when a call signal is received, a response signal including information for notifying the receiving buffer size of the own terminal is sent to the calling side, and while image information is being transmitted in the UDP mode, a buffer overflow of the partner terminal is detected. If the data accumulation value of one or more packets carrying information exceeds the size of the receiving buffer included in the response signal received from the partner terminal, a predetermined number of packets are transmitted until the next packet carrying image information is transmitted. The delay time is inserted, and whenever the buffer overflow of the partner terminal is detected even after the delay time is inserted, the delay time is increased each time.

Further, according to ITU-T Recommendation T. 38, an Internet facsimile transmission device having a transmission function and performing real-time communication using the Internet
A buffer overflow detecting means for detecting a buffer overflow of the partner terminal during image information transmission in the P mode;
When the buffer overflow detecting means detects a buffer overflow of the partner terminal, an image information transmitting means for inserting a predetermined delay time into a transmission interval of each packet carrying image information is provided.

Further, according to ITU-T Recommendation T. 38, an Internet facsimile transmission device having a transmission function and performing real-time communication using the Internet
A buffer overflow detecting means for detecting a buffer overflow of the partner terminal during image information transmission in the P mode;
When the buffer overflow detection means detects a buffer overflow of the partner terminal, a predetermined delay time is inserted into the transmission interval of each packet carrying image information, and after the delay time insertion, the buffer overflow detection means keeps the buffer overflow detection means of the partner terminal. Each time a buffer overflow is detected, an image information transmitting means for increasing the delay time is provided.

Further, according to ITU-T Recommendation T. 38, an Internet facsimile transmission device having a transmission function and performing real-time communication using the Internet
A buffer overflow detecting means for detecting a buffer overflow of the partner terminal during image information transmission in the P mode;
When the buffer overflow detection means detects a buffer overflow of the partner terminal, when the data accumulation value of one or more packets carrying image information exceeds the reception buffer size included in the response signal received from the partner terminal,
An image information transmitting means for inserting a predetermined delay time before transmitting the next packet carrying image information is provided.

Also, according to ITU-T Recommendation T. 38, an Internet facsimile transmission device having a transmission function and performing real-time communication using the Internet
A buffer overflow detecting means for detecting a buffer overflow of the partner terminal during image information transmission in the P mode;
When the buffer overflow detection means detects a buffer overflow of the partner terminal, when the data accumulation value of one or more packets carrying image information exceeds the reception buffer size included in the response signal received from the partner terminal,
A predetermined delay time is inserted before the next packet carrying image information is transmitted, and when the buffer overflow detection means detects the buffer overflow of the partner terminal even after the delay time insertion, An image information transmitting means for increasing the delay time is provided.

Further, according to ITU-T Recommendation T. An Internet facsimile receiving apparatus that has a receiving function and performs real-time communication using the Internet is provided with the recommendation T.38. Upon receipt of the paging signal, an incoming call response means for transmitting a response signal including information for notifying the receiving buffer size of the terminal to the calling side is provided.

[0021]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
An embodiment of the present invention will be described in detail.

FIG. 1 shows an ITU according to an embodiment of the present invention.
-T Recommendation T. 38 shows an example of a real-time Internet facsimile communication system assumed by 38.

In this case, the real-time Internet facsimile communication system is the Internet INET.
And group 3 facsimile machine functions and ITU-T Recommendation T. It comprises an Internet facsimile machine FX1 and an Internet facsimile machine FX2 having 38 transmission functions.

In this case, the Internet facsimile machine FX1 and the Internet facsimile machine F
X2 facsimile communication is based on ITU-T Recommendation T.40.
38.

FIG. 2 shows a configuration example of the Internet facsimile machine FX (FX1, FX2). In addition,
This Internet facsimile machine FX is connected to an analog public network PSTN and communicates with a group 3 facsimile machine (not shown).
It also has a gateway function from the facsimile machine to the Internet INET.

In FIG. 1, a system control unit 1 performs control processing of each unit of the Internet facsimile machine FX and a facsimile transmission control procedure (ITU-T Recommendation T.3).
0 procedure) and the real-time transmission control procedure (I
TU-T Recommendation T. The system memory 2 stores a control processing program to be executed by the system control unit 1 and various data necessary for executing the processing program. A work area of the system control unit 1, such as a transmission / reception buffer applied when transmitting / receiving image information, is configured. The parameter memory 3 is for storing various kinds of information unique to the Internet facsimile machine FX. The clock circuit 4 outputs current time information.

The scanner 5 is for reading an original image at a predetermined resolution, the plotter 6 is for recording and outputting an image at a predetermined resolution, and the operation display unit 7 is a facsimile apparatus. To operate,
It consists of various operation keys and various indicators.

The encoding / decoding unit 8 encodes and compresses the image signal and decodes the encoded and compressed image information into the original image signal.
This is for storing a large number of image information in a coded and compressed state.

The group 3 facsimile modem 10 realizes a group 3 facsimile modem function, and exchanges a transmission procedure signal (a low-speed modem function (V.21 modem)) and mainly exchanges image information. High-speed modem function (V.17 modem,
V. 34 modem, V.34. 29 modem, V.29. 27ter modem etc.).

The network control device 11 is for connecting the Internet facsimile machine FX to the analog public network PSTN, and has an automatic transmission / reception function.

The Internet communication control unit 12 connects this real-time Internet gateway device to the Internet INET, and exchanges various data via the Internet INET. For analyzing the received TCP / IP packet or UDP / IP packet and extracting the received information,
The group 3 protocol information generator 14 converts the received information output from the packet analyzer 13 into the corresponding group 3 transmission procedure signal information in the real-time transmission procedure.

The group 3 protocol information extracting unit 15
In the real-time transmission procedure, this is for extracting group 3 facsimile transmission procedure information to be transmitted,
The packet converter 16 converts the group 3 facsimile transmission procedure information output from the group 3 protocol information extractor 15 into TCP / IP packet data or UDP / IP
The output data is converted into packet data, and the output data is applied to the Internet communication control unit 12.

The system control unit 1, system memory 2, parameter memory 3, clock circuit 4, scanner 5, plotter 6, operation display unit 7, encoding / decoding unit 8, image storage device 9, group 3 facsimile modem 10, network controller 11, group 3 protocol information generator 14,
The group 3 protocol information extracting unit 15 is connected to the internal bus 17, and data exchange between these elements is mainly performed through the internal bus 17.

Data exchange between the network controller 11 and the group 3 facsimile modem 10 is directly performed. The operation mode of the packet analysis unit 13 and the packet conversion unit 16 is TCP / I
When in the P mode, it is set to process TCP / IP packets, and the communication mode is UDP / IP.
When in the IP mode, it is set to process UDP / IP packets.

FIG. 3 is a diagram showing ITU-T Recommendation T.30. 38 shows an example of the procedure of T.38. In the figure, the transmitting side and the receiving side are, for example, the Internet facsimile machine FX1 and the Internet facsimile machine FX shown in FIG.
2 respectively. This procedure is for the case where the ECM mode is not used for image information transmission.

First, the transmitting side sends a SETUP message to the receiving side.
The receiving side that has transmitted the packet and made a connection request, and has received the SETUP packet, transmits a CONNECT packet to the transmitting side to confirm the call connection.

As a result, a communication path between the transmitting side and the receiving side is established. Three
A signal (T30IND: CED) corresponding to a predetermined tone signal CED (called station identification signal) of the 0 procedure is transmitted to the transmitting side, and a signal (T30IN) corresponding to the flag signal is transmitted.
D: Flag), a group 3 facsimile transmission procedure signal, a signal NSF for notifying an optional transmission function of the own terminal, a signal CSI for notifying an identification signal of the own terminal, and a signal of the own terminal. A signal (V) corresponding to the signal DIS for notifying the standard transmission function
21 HDLC: NSF / CSI / DIS) are sequentially transmitted to the transmission side.

As a result, the transmitting side knows the identification signal and the transmitting function of the receiving side, and sets the transmitting function and the modem speed to be used at that time based on the notified transmitting function. Next, the transmitting side, following the signal corresponding to the flag signal (T30IND: Flags), is a group 3 facsimile transmission procedure signal, and notifies the signal TSI for notifying the identification signal of its own terminal and the transmission function to be used. (V21 HDLC: TSI / DCS) respectively corresponding to the signal DCS for performing the transmission.

Accordingly, the receiving side receives the signal (V21HDL)
C: TSI / DCS), it acquires the identification information of the partner terminal (transmitting side) and the transmission function used at that time.

Then, on the receiving side, following the signal (T30IND: Flags) corresponding to the flag signal, the group 3
A signal (V21) that is a facsimile transmission procedure signal and corresponds to a signal CFR for notifying that reception preparation has been completed.
HDLC: CFR) to the transmitting side.

When the preparation for transmitting the image information is completed in this way, the transmitting side transmits a signal (T3) corresponding to a training signal for retraining the modem.
0IND: Speed) is transmitted to the receiving side. Subsequently, the image data of the transmission image information is divided into a plurality of pieces, and each divided image information is divided into packet data (in FIG. 3, "V.17").
non ECM: Image data ").

When the transmission of the image information is completed, a signal (T30IND: Flags) corresponding to the flag signal is transmitted to the receiving side, and a signal E indicating a group 3 facsimile procedure signal indicating the end of the image information transmission.
A signal (V21HDLC: EOP) corresponding to the OP is transmitted to the receiving side.

On the other hand, on the receiving side, the signal (T30IND: S
speed), the process shifts to preparation for receiving image information.
When a packet carrying image information is received, divided image information included in the packet is sequentially taken out, linked image information is created, and the image information is stored in the image storage device 9. In this case, as a post-transmission signal after receiving the image information,
Since the signal (V21 HDLC: EOP) is received, it is confirmed that the image information reception is completed.

If the reception result of the image information at that time is good, the receiving side is a group 3 facsimile procedure signal following the signal (T30IND: Flags) corresponding to the flag signal, and the image information is received. A signal (V21HDL) corresponding to the signal MCF indicating normal termination
C: EOP) to the transmitting side.

Thus, the transmitting side recognizes that the image information has been normally received by the receiving side. Thereafter, the transmitting side transmits a signal (T30IND: Fla) corresponding to the flag signal.
gs), a signal (V21HDLC: DCN) corresponding to the signal DCN for instructing the line restoration, which is a group 3 facsimile procedure signal, is transmitted to the receiving side.

Then, the receiving side receives the signal (T30IND:
Upon receiving the signals (Flags) and the signal (V21HDLC: DCN), the image information receiving operation ends.

In this manner, the image information is transmitted from the transmitting side to the receiving side.

Here, the signal (T30IN) shown in FIG.
D: “Signal name”) is defined in ITU-T Recommendation T. The signal (V21HDLC: “signal name”) is a signal for notifying the detection of a tonal signal according to ITU-T Recommendation T.30. This is a signal for carrying a binary signal in accordance with H.30. Also, “V.21”, ITU-T Recommendation V. 21 that the signal is carried by the modem.
“C” indicates that the signal is an HDLC framed signal.

The transmission procedure shown in FIG.
Recommendation T.30 corresponding to the T.30 standard procedure 38, which is recommended in Recommendation T.38. When the optional procedures (for example, file transfer mode, etc.) of the T.30 are applied, the recommendation T.30 corresponding thereto is applied. 38 procedures are performed. At this time, the signals exchanged between the transmitting side and the receiving side have the same format as the signals in FIG.

As described above, this Recommendation T. 38
When the real-time Internet facsimile communication according to the procedure is performed in the UDP / IP mode, a reception buffer prepared on the receiving side may overflow.

This is because the decoding process of the image information has more processing steps than the encoding process, and therefore, the image information data stored in the receiving buffer by the decoding process for the reception error check is reduced. This is because the amount of data per unit time to be received and added to the reception buffer may be larger than the amount of data per unit time to be processed.

Here, the image information is decomposed into data units of the UDP packet from the transmission side and transmitted in the unit of the UDP packet. Therefore, the reception side receives the image information in the data unit of the UDP packet. Data accumulation in the reception buffer is also performed in data units of the UDP packet.

In view of such a situation, in the present embodiment, upon detecting a buffer overflow on the receiving side, the transmitting side thereafter sets a delay time (for example, 32 millimeters) between UDP packets carrying image information. Seconds).

As a result, the transmission timing of the image information on the transmission side is adjusted so that the buffer overflow on the reception side does not occur, and the image information can be transmitted smoothly.

In the post-message procedure of the image information transmitting procedure, the transmitting side transmits a signal RTN (in non-ECM mode).
Alternatively, when the signal PPR (in the ECM mode) is received from the receiving side as a response signal, it is determined that a buffer overflow has occurred on the receiving side.

As a result, a special mechanism for notifying the transmission side of the occurrence of the buffer overflow on the receiving side is not required, and the occurrence of the buffer overflow on the receiving side is notified to the transmitting side in the mechanism of the conventional transmission procedure. Can be notified.

FIGS. 4, 5 and 6 show an example of processing on the transmitting side when performing image information communication in the UDP mode.

When a document to be transmitted is set on the scanner 5 and the user inputs a transmission destination (process 101) and presses the start key (the result of the determination 102 is YES), the image of the document set on the scanner 5 is read. (Process 103) The image data obtained thereby is encoded and compressed by the encoding method at the time of storage, and is stored in the image storage device 9 (Process 10).
4).

Next, a SETUP packet is sent to the designated destination Internet facsimile machine FX to call the destination (step 105), and a CONNECT packet is received from the destination Internet facsimile apparatus FX (step 106). ). Thereby, a virtual communication path is formed between the Internet facsimile machine FX on the transmitting side and the Internet facsimile machine FX on the receiving side.

Then, a predetermined pre-transmission procedure is executed to set a transmission function (encoding method, paper size, resolution, etc.) to be used with the destination (process 107).

Next, the delay time TD between the UDP packets carrying the image information data is initialized to 0 ms (step 10).
8).

Then, the image information data stored from the image storage device 9 is read (process 109), and re-converted into image information data of the encoding method set between the destination and the destination (process 110).
One packet is transmitted (process 111), and a delay time TD is waited (process 112).

Here, it is checked whether or not the transmission of the image information for one page has been completed (decision 113). If the result of the decision 113 is NO, the process returns to step 109, where the remaining image information data is read and re-read. Perform the conversion. Here, even after the reconversion of the image data for one page is completed, the loop processing of the processing 111 to the determination 113 is repeatedly executed until the transmission of the reconverted data is completed. If the re-conversion is unnecessary, the process 110 is not performed.

The transmission of the image data for one page is completed.
If the result of decision 113 is YES, it is checked whether there is a next transmission page (decision 115), and if the result of decision 115 is YES, signal MPS is sent out as a post-message signal (process 116), and Is received (process 117).

When the response signal is received, the content is
It is checked whether the TN is a TN (decision 118), and the decision 118
If the result is YES, the receiving side determines that a buffer overflow has occurred, and increases the value of the delay time TD by a predetermined value MM (for example, 32 milliseconds) (process 119).

Here, it is checked whether or not the mode in which the same page can be retransmitted is set (decision 120). If the result of decision 120 is YES, the page transmitted immediately before is set as the transmission page (step 120). Processing 12
1) Return to step 109 and retransmit the same page. Therefore, in this case, the delay time TD updated to a value larger by the predetermined value MM is inserted for each UDP packet carrying image information data for the same page.

If retransmission of the same page is prohibited and the result of determination 120 is NO, the next page is set as the transmission page (step 12).
2) Return to step 109 and resend the next page. Therefore, in this case, the delay time TD updated to a value larger by the predetermined value MM is inserted for each UDP packet carrying image information data for the next page.

When the signal MCF is received as a response signal and the result of the determination 118 is NO, the process proceeds to a process 122, and the process returns to the process 109 with the next page set as the transmission page, and returns to the process 109. Resend the page. Therefore, in this case, every time image information data of the reception data buffer size is transmitted for the next page,
A delay time TD that is not updated (that is, 0 ms when there is no reception error) is inserted.

On the other hand, if the transmission of the last page is completed and the result of determination 115 is NO, signal EOP is transmitted as a post-message signal (process 125), and a response signal from the destination is received (process 126). ).

When the response signal is received, the content is
It is checked whether or not it is a TN (decision 127).
Is YES, the receiving side determines that a buffer overflow has occurred, and increases the value of the delay time TD by a predetermined value MM (for example, 32 milliseconds) (process 128).

Here, it is checked whether or not the mode in which the same page can be retransmitted is set (decision 129). If the result of decision 129 is YES, the page transmitted immediately before is set as the transmitted page ( Processing 13
0), returning to the processing 109, and retransmitting the same page. Therefore, in this case, the delay time TD updated to a value larger by the predetermined value MM is inserted for each UDP packet carrying image information data for the next page.

If retransmission of the same page is prohibited and the result of determination 129 is NO, a predetermined transmission end procedure is executed (step 131), and a predetermined line restoration procedure is executed (step 131). (Process 132) The transmission operation ends.

When the signal MCF is received as the response signal and the result of the determination 127 is NO, the process proceeds to a process 131, where a predetermined transmission end procedure is executed.
After performing a predetermined line restoration procedure, the transmission operation ends.

FIG. 7 shows an example of processing on the receiving side when image information communication is performed in the UDP mode.

When the SETUP packet is received (Process 2
01), sends a CONNECT packet to the transmission source (process 202), executes a predetermined pre-transmission procedure, and negotiates and determines a transmission function or the like to be used for image information communication at that time (process 203).

Next, the image information is received and the image
Then, the received image information is decoded and a reception error is checked (process 205). The processes 204 and 205 are repeatedly executed until the reception operation of one page is completed (NO loop of the judgment 206).

When the reception of the image information for one page is completed and the result of determination 206 is YES, it is checked whether or not the reception result at that time is OK (determination 207).
If a buffer overflow does not occur and there is no reception error, the result of decision 207 is YES.

Here, when the result of determination 207 is YES, a post-message signal is received from the transmitting side (process 208), and a signal MCF is returned (process 209). If the result of determination 207 is NO, a post-message signal is received from the transmitting side (processing 210) and the signal RT
N is returned (process 211).

Then, it is checked whether or not it is notified that there is a next transmission page (decision 212). If the result of decision 212 is YES, the process returns to step 205 to perform the image information receiving operation of the next page. .

When the result of determination 212 is NO, a predetermined transmission termination procedure is executed (step 213), a predetermined line restoration procedure is executed (step 214), and the transmission operation is terminated.

In the above-described embodiment, when the buffer overflow on the receiving side is detected, the next U-packet carrying the image information to be transmitted thereafter is transmitted to the next U-packet.
The delay time TD was inserted before the transmission of the DP packet. However, if the insertion timing of the delay time TD is adjusted according to the size of the reception data buffer on the receiving side, the ratio of the inserted delay time TD is reduced. It is possible to reduce the communication time.

The receiving side notifies the transmitting side of the receiving data buffer size by arranging the receiving data buffer size provided in the terminal itself in the user / user information element of the CONNECT packet. .

In this way, when notifying the receiving data buffer size from the receiving side to the transmitting side, it is not necessary to exchange a special signal, and such a function can be easily realized.

FIGS. 8, 9 and 10 show that in this case,
An example of processing on the transmission side when performing image information communication in the UDP mode is shown.

When the transmission original is set on the scanner 5, the user inputs the transmission destination (process 301), and presses the start key (the result of the determination 302 is YES), and the image of the original set on the scanner 5 is read. (Process 303) The image data obtained thereby is encoded and compressed by the encoding method at the time of accumulation, and is stored in the image storage device 9 (Process 30).
4).

Next, a SETUP packet is sent to the designated destination Internet facsimile machine FX to call the destination (step 305), and the destination Internet facsimile machine FX sends the received data buffer size notification information from the destination Internet facsimile machine FX. The CONNECT packet including the CONNECT packet is received, and the reception data buffer size BA is acquired (process 3).
06). Thereby, a virtual communication path is formed between the Internet facsimile machine FX on the transmitting side and the Internet facsimile machine FX on the receiving side.

Then, a predetermined pre-transmission procedure is executed to set a transmission function (encoding method, paper size, resolution, etc.) to be used with the destination (process 307).

Next, the delay time TD between the UDP packets carrying the image information data is initialized to 0 ms (step 30).
8) The variable SDZ for storing the amount of transmission data is initialized to 0 (process 310).

Then, the image information data stored by the image storage device 9 is read (process 311), and is reconverted into image information data of the encoding system set between the destination and the destination (process 312).
One packet is transmitted (process 313), and it is checked whether transmission of image information for one page has been completed (decision 314).

If the result of decision 314 is NO,
The value of the variable SDZ is updated by adding the data size of the UDP packet transmitted in the process 313 to the variable SDZ (process 315), and it is determined whether or not the value of the variable SDZ is larger than the reception data buffer size BA. Check (decision 316). If the result of decision 316 is NO,
Returning to the process 311, the remaining image information data is transmitted.

When the result of the determination 316 is YES, the process waits for the delay time TD (process 317), and the process 31
After returning to 0 and initializing the value of the variable SDZ, the remaining image information data is transmitted.

Here, even after the re-conversion of the image data for one page is completed, the loop processing of the steps 310 to 317 is repeatedly executed until the transmission of the re-converted data is completed. If re-conversion is not required, process 3
12 is not executed.

The transmission of the image data for one page is completed.
If the result of decision 314 is YES, it is checked whether there is a next transmission page (decision 318), and if the result of decision 318 is YES, signal MPS is sent out as a post-message signal (process 319), and Is received (process 320).

When the response signal is received, the content is
It is checked whether the TN is a TN (decision 321).
Is YES, the receiving side determines that a buffer overflow has occurred, and increases the value of the delay time TD by a predetermined value MM (for example, 32 milliseconds) (process 322).

Here, it is checked whether or not the mode in which the same page can be retransmitted is set (decision 323). If the result of decision 323 is YES, the page transmitted immediately before is set as the transmission page ( Process 32
4) Return to step 310 and retransmit the same page. Therefore, in this case, every time image information data of the reception data buffer size is transmitted for the same page, the delay time TD updated to a value larger by the predetermined value MM is inserted.

If retransmission of the same page is prohibited and the result of determination 323 is NO, the next page is set as the transmission page (step 32).
5) Return to processing 310 and retransmit the next page. Therefore, in this case, every time image information data of the reception data buffer size is transmitted for the next page, the delay time TD updated to a value larger by the predetermined value MM is inserted.

If signal MCF is received as a response signal and the result of determination 321 is NO, the process proceeds to step 325, where the next page is set as the transmission page, and the process returns to step 310, where the next page is set. Resend the page. Therefore, in this case, every time image information data of the reception data buffer size is transmitted for the next page,
A delay time TD that is not updated (that is, 0 ms when there is no reception error) is inserted.

On the other hand, if the transmission of the last page has been completed and the result of determination 318 is NO, signal EOP is transmitted as a post-message signal (process 326), and a response signal from the destination is received (process 327). ).

When the response signal is received, the content is
It is determined whether the TN is a TN (decision 328).
If the result is YES, the receiving side determines that a buffer overflow has occurred, and increases the value of the delay time TD by a predetermined value MM (for example, 32 milliseconds) (process 329).

Here, it is checked whether or not the mode in which the same page can be retransmitted is set (decision 330). If the result of decision 330 is YES, the page transmitted immediately before is set as the transmission page (step 330). Process 33
1) Return to step 310 and retransmit the same page. Therefore, in this case, every time image information data of the reception data buffer size is transmitted for the same page, the delay time TD updated to a value larger by the predetermined value MM is inserted.

If retransmission of the same page is prohibited and the result of determination 330 is NO, a predetermined transmission end procedure is executed (step 332), and a predetermined line restoration procedure is executed (step 332). (Step 333) The transmission operation ends.

When the signal MCF is received as a response signal and the result of the determination 328 is NO, the process proceeds to a process 332, where a predetermined transmission end procedure is executed.
After performing a predetermined line restoration procedure, the transmission operation ends.

FIG. 11 shows an example of processing on the receiving side when image information communication is performed in the UDP mode in this case.

When a SETUP packet is received (Process 4
01), sends a CONNECT packet including information for notifying the value of the reception data buffer size of the own terminal to the transmission source (process 402), executes a predetermined pre-transmission procedure, and performs image information communication at that time. Negotiate and determine the transmission function to be used (process 403).

Next, the image information is received and the image
Then, the received image information is decoded and a reception error is checked (process 405). Steps 404 and 405 are repeatedly executed until the reception operation of one page is completed (NO loop of judgment 406).

When the reception of the image information for one page is completed and the result of judgment 406 is YES, it is checked whether or not the reception result at that time is OK (judgment 407).
If there is no buffer overflow and no reception error, the result of decision 407 is YES.

Here, when the result of determination 407 is YES, a post-message signal is received from the transmitting side (process 408), and a signal MCF is returned (process 409). When the result of the judgment 407 is NO, a post-message signal is received from the transmitting side (process 410), and the signal RT is received.
N is returned (process 411).

Then, it is checked whether or not it is notified that there is a next transmission page (decision 412). When the result of decision 412 is YES, the process returns to step 405 to perform the image information receiving operation of the next page. .

When the result of determination 412 is NO, a predetermined transmission end procedure is executed (step 413), a predetermined line restoration procedure is executed (step 414), and the transmission operation ends.

In the above-described embodiment, the case where the image information communication is performed in the non-ECM mode has been described. However, the present invention can be similarly applied to the case where the image information communication is performed in the ECM mode. In that case,
The detection of the buffer overflow on the receiving side is performed by the signal PPR.
Can be determined by receiving.

In the above-described embodiment, the case where the transmission original is read and the transmission image information is created has been described. However, the present invention is similarly applied to the case where the transmission image information is handled as file data or the like. Can be.
Therefore, the present invention is also applicable to a data communication device in another device form such as a personal computer device.
The same can be applied.

[0112]

As described above, according to the present invention,
Upon detecting the buffer overflow on the receiving side, the transmitting side thereafter transmits a UDP packet carrying image information and a UDP packet.
Since the delay time is inserted between the packets, the transmission timing of the image information on the transmission side is adjusted so that the buffer overflow on the reception side does not occur. There is an effect that image information can be transmitted.

In the post-message procedure of the image information transmitting procedure, the transmitting side transmits the signal RTN (in the non-ECM mode).
Alternatively, when a signal PPR (in the ECM mode) is received from the receiving side as a response signal, it is determined that a buffer overflow has occurred on the receiving side, so a special buffer overflow notification for notifying the transmitting side of the occurrence of buffer overflow on the receiving side. There is no need for a mechanism, and the effect of being able to notify the transmission side of the occurrence of the buffer overflow on the reception side is obtained in the conventional transmission procedure.

Further, the insertion timing of the delay time TD is
Since the adjustment is made in accordance with the reception data buffer size on the reception side, the effect of reducing the ratio of the inserted delay time TD and shortening the communication time is also obtained.

The receiving side notifies the transmitting side of the receiving data buffer size by arranging the receiving data buffer size provided in its own terminal in the user / user information element of the CONNECT packet. Therefore, when notifying the reception data buffer size from the receiving side to the transmitting side, it is not necessary to exchange a special signal, and the effect that such a function can be easily realized is obtained.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating ITU-T Recommendation T.1 according to an embodiment of the present invention.
38 is a block diagram showing an example of a real-time Internet facsimile communication system assumed by 38.

FIG. 2 is an Internet facsimile machine FX (FX
1, FX2) is a block diagram showing a configuration example.

FIG. 3 shows ITU-T Recommendation T. 38 is a timing chart showing an example of the procedure of 38.

FIG. 4 is a flowchart illustrating an example of processing on the transmission side when performing image information communication in a UDP mode.

FIG. 5 is a flowchart (continued) showing an example of processing on the transmission side when performing image information communication in the UDP mode.

FIG. 6 is a flowchart (continued) showing an example of processing on the transmission side when performing image information communication in the UDP mode.

FIG. 7 is a flowchart illustrating an example of processing on the receiving side when image information communication is performed in the UDP mode.

FIG. 8 is a flowchart showing another example of processing on the transmission side when performing image information communication in the UDP mode.

FIG. 9 is a flowchart (continued) illustrating another example of processing on the transmission side when performing image information communication in the UDP mode.

FIG. 10 is a flowchart (continued) showing another example of processing on the transmission side when performing image information communication in the UDP mode.

FIG. 11 is a flowchart showing another example of the processing on the receiving side when performing image information communication in the UDP mode.

[Explanation of symbols]

FX, FX1, FX2 Internet facsimile machine

Continued on the front page F-term (reference) 5C062 AA02 AA29 AB42 AC21 AC45 AC58 AE14 BA00 5C075 AB90 BB05 CD21 CD22 CE02 CE07 CF90 FF90 5K030 GA13 HA07 HB04 HC01 JT05 KA19 LA08 LB17 LC11 MA00 5K034 AA07 CB06 CC04 MM06 CC04 DD13 JJ25 JJ35 KK42 KK54 KK56

Claims (14)

[Claims] 1. An ITU-T Recommendation T. 38. An Internet facsimile apparatus having a communication function and performing real-time communication using the Internet, comprising: a buffer overflow detecting means for detecting a buffer overflow of a partner terminal during image information transmission in a UDP mode; An internet facsimile apparatus, comprising: an image information transmitting means for inserting a predetermined delay time into a transmission interval of each packet carrying image information upon detecting a buffer overflow of the above. 2. An ITU-T Recommendation T.2. 38. An internet facsimile apparatus having a communication function and performing real-time communication using the Internet, wherein buffer overflow detection means for detecting a buffer overflow of a partner terminal during image information transmission in a UDP mode; When the buffer overflow is detected, a predetermined delay time is inserted into the transmission interval of each packet carrying image information, and when the buffer overflow detection means detects the buffer overflow of the partner terminal even after the delay time is inserted, An Internet facsimile machine comprising image information transmitting means for increasing the delay time each time. 3. An ITU-T Recommendation T.3. An Internet facsimile apparatus which has a communication function and performs real-time communication using the Internet. 38, upon receipt of the call signal, a response signal including information for notifying the reception buffer size of the terminal itself is provided.
Incoming call responding means for sending to the calling side; buffer overflow detecting means for detecting a buffer overflow of the partner terminal during transmission of image information in the UDP mode; When the data accumulated value of one or more packets to be carried exceeds the size of the receiving buffer included in the response signal received from the other terminal, a predetermined delay is required until the next packet carrying image information is transmitted. An Internet facsimile apparatus comprising image information transmitting means for inserting time. 4. An ITU-T Recommendation T. An Internet facsimile apparatus which has a communication function and performs real-time communication using the Internet. 38, upon receipt of the call signal, a response signal including information for notifying the reception buffer size of the terminal itself is provided.
Incoming call responding means for sending to the calling side; buffer overflow detecting means for detecting a buffer overflow of the partner terminal during transmission of image information in the UDP mode; and image information when the buffer overflow detecting means detects a buffer overflow of the partner terminal. When the data accumulated value of one or more packets to be carried exceeds the size of the receiving buffer included in the response signal received from the other terminal, a predetermined delay is required until the next packet carrying image information is transmitted. The Internet, characterized in that the Internet is provided with image information transmitting means for increasing the delay time each time the buffer overflow detection means detects the buffer overflow of the partner terminal after inserting the time and after inserting the delay time. Facsimile machine. 5. The buffer overflow detecting means, when receiving a signal RTN or a signal PPR from a partner terminal, determines that the partner terminal has caused a buffer overflow. Or an Internet facsimile apparatus according to claim 4. 6. An ITU-T Recommendation T.6. 38 In a control method of an Internet facsimile apparatus having a communication function and performing real-time type communication using the Internet, during transmission of image information in a UDP mode, when a buffer overflow of a partner terminal is detected, a transmission interval of each packet carrying image information is set. A method for controlling an Internet facsimile apparatus, wherein a predetermined delay time is inserted. 7. An ITU-T Recommendation T.7. 38 In a control method of an Internet facsimile apparatus having a communication function and performing real-time type communication using the Internet, during transmission of image information in a UDP mode, when a buffer overflow of a partner terminal is detected, a transmission interval of each packet carrying image information is set. A method for controlling an Internet facsimile apparatus, wherein a predetermined delay time is inserted, and each time a buffer overflow of a partner terminal is detected after the delay time is inserted, the delay time is increased. 8. An ITU-T Recommendation T. 38, a control method for an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet. 38, upon receipt of the call signal, a response signal including information for notifying the reception buffer size of the terminal itself is provided.
While transmitting to the calling side, if the buffer overflow of the partner terminal is detected during image information transmission in the UDP mode, the data accumulated value of one or more packets carrying the image information is included in the response signal received from the partner terminal. When the size of the receiving buffer is exceeded,
A method for controlling an Internet facsimile apparatus, wherein a predetermined delay time is inserted before a next packet carrying image information is transmitted. 9. An ITU-T Recommendation T. 38, a control method for an Internet facsimile apparatus having a communication function and performing real-time communication using the Internet. 38, upon receipt of the call signal, a response signal including information for notifying the reception buffer size of the terminal itself is provided.
While transmitting to the calling side, if the buffer overflow of the partner terminal is detected during image information transmission in the UDP mode, the data accumulated value of one or more packets carrying the image information is included in the response signal received from the partner terminal. When the size of the receiving buffer is exceeded,
A predetermined delay time is inserted until the next packet carrying image information is transmitted, and when the buffer overflow of the partner terminal is detected even after the insertion of the delay time, the delay time is increased each time. A method for controlling an Internet facsimile machine, characterized in that: 10. An ITU-T Recommendation T.10. 38. An internet facsimile transmission device having a transmission function and performing real-time communication using the Internet, wherein buffer overflow detection means for detecting a buffer overflow of a partner terminal during image information transmission in the UDP mode, An internet facsimile transmission apparatus, comprising: an image information transmitting means for inserting a predetermined delay time into a transmission interval of each packet carrying image information when a buffer overflow of a terminal is detected. 11. An ITU-T Recommendation T.11. 38. An internet facsimile transmission device having a transmission function and performing real-time communication using the Internet, comprising: a buffer overflow detection means for detecting a buffer overflow of a partner terminal during image information transmission in a UDP mode; When detecting the buffer overflow of the terminal, a predetermined delay time is inserted in the transmission interval of each packet carrying image information, and when the buffer overflow detection means detects the buffer overflow of the partner terminal even after the delay time insertion, An Internet facsimile transmission device comprising an image information transmission means for increasing the delay time each time. 12. An ITU-T Recommendation T.12. 38. An internet facsimile transmission device having a transmission function and performing real-time communication using the Internet, wherein buffer overflow detection means for detecting a buffer overflow of a partner terminal during image information transmission in the UDP mode, When detecting the buffer overflow of the terminal, if the data accumulated value of one or more packets carrying the image information exceeds the receiving buffer size included in the response signal received from the partner terminal,
An Internet facsimile transmission apparatus, comprising: an image information transmitting unit that inserts a predetermined delay time until a next packet carrying image information is transmitted. 13. An ITU-T Recommendation T. 38. An internet facsimile transmission device having a transmission function and performing real-time communication using the Internet, wherein buffer overflow detection means for detecting a buffer overflow of a partner terminal during image information transmission in the UDP mode, When detecting the buffer overflow of the terminal, if the data accumulated value of one or more packets carrying the image information exceeds the receiving buffer size included in the response signal received from the partner terminal,
A predetermined delay time is inserted before the next packet carrying image information is transmitted, and when the buffer overflow detection means detects the buffer overflow of the partner terminal even after the delay time insertion, An Internet facsimile transmission device comprising image information transmission means for increasing a delay time. 14. An ITU-T Recommendation T.14. An Internet facsimile receiving apparatus that has a receiving function and performs real-time communication using the Internet. 38, upon receipt of the call signal, a response signal including information for notifying the reception buffer size of the terminal itself is provided.
An Internet facsimile receiving apparatus comprising an incoming call response means for sending out to a calling side.