JP3871045B2 - Call recording apparatus and call recording method - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a technique for recording communication such as voice data transmitted via a communication line.
[0002]
[Prior art]
Transactions are sometimes made using telephone lines in banking, securities and other financial relationships, telemarketing such as mail order sales, and public works such as horse racing. In such a case, it may be required to record the contents of the call as confirmation or proof of the transaction contents, and a communication recording device that automatically records the contents of the call is used.
[0003]
By the way, ISDN (Integrated Services Digital Network) is widely used as a communication network that can connect different services such as telephone and data communication using the same digital exchange and digital path. Since ISDN digitizes and transmits information, signal degradation is less than that of analog lines, and high-speed communication is possible.
[0004]
Here, ISDN will be briefly described. ISDN includes one signal channel (D channel) for transmitting control information such as call control information, and a plurality of information channels (B channel) for transmitting user information. The B channel is a communication path through which voice data is transmitted during voice communication. The voice data from the ISDN communication network side (calling party side) and the voice data from the terminal side use different communication paths. Is transmitted.
[0005]
Japanese Patent Laid-Open No. 2000-49979 discloses an ISDN call recording device that supports digital communication such as ISDN. This is to receive the signals transmitted by the communication network and the private branch exchange (PBX), monitor the procedure exchanged on the signal channel, and according to the connection / disconnection of the line, the voice data of the corresponding information channel Is recorded on a recording medium such as a hard disk.
[0006]
An example of a communication system equipped with such a call recording device is shown in FIG. As shown in this figure, in a communication system using ISDN, a terminal 105 provided with a call recording device 101 is connected to a communication network 102 via a DSU 103 and a PBX 104. The call recording device 101 does not have a transmission function, has only a reception function, and is connected between the DSU 103 and the PBX 104. On the other hand, the partner terminal 105A is connected to the communication network 102 via the DSU 103A.
[0007]
The call recording device 101 receives control information and a message transmitted / received between the communication network 102 and the terminal 105, and is transmitted from the communication network 102 to the terminal 105 or from the terminal 105 to the communication network 102 based on the control information and message. The communication contents are recorded on a recording medium or the like.
[0008]
However, when such a call recording device 101 is used in a call center where a large number of operators handle calls, the voice signals of a plurality of calls connected to a plurality of telephone lines and inputted from the respective telephone lines are encoded, It is recorded as voice data in one call recording device 101. In such a case, index data is required to reproduce the recorded one.
[0009]
In accordance with this situation, the voice for each call detected by the means for detecting the start and end of the call for each telephone line is recorded, and the time when the call was made, the line (channel) of the call A recording / reproducing apparatus configured to record an identification record as index data of each call voice and to search and reproduce the call voice recorded based on the index data is considered.
[0010]
In the recording / reproducing apparatus disclosed in Japanese Patent Laid-Open No. 2002-57788, while detecting a busy state and recording a voice for each call, a DTMF (Dual Tone Multi-Frequency) signal included in each call is decoded. Records as an index associated with the voice of each call. A call identification code (hereinafter referred to as a DTMF code) based on a DTMF signal recorded as an index is, for example, a person-in-charge code indicating the operator itself, a destination code indicating the other party of the call, etc. The one entered as is used.
[0011]
An overall functional block diagram of such a conventional call recording apparatus 101 is shown in FIG. As shown in the figure, the conventional call recording apparatus 101 includes a network side reception unit 1201, a terminal side reception unit 1202, an addition unit 1203, an information channel recording unit 1204, a call control detection unit 1205, and a DTMF detection. Part 1206.
[0012]
The network side receiving unit 1201 receives communication from the network side and separates a signal channel through which call control information is exchanged and an information channel through which voice data is exchanged.
[0013]
The terminal side receiving unit 1202 receives communication from the terminal side and separates the signal channel and the information channel.
[0014]
The adding unit 1203 adds (multiplexes) the information channels separated by the network side receiving unit 1201 and the terminal side receiving unit 1202. As a result, the transmission / reception is recorded together. By recording together, it is possible to reduce redundancy by recording transmission / reception separately and to reduce recording capacity.
[0015]
The information channel recording unit 1204 records the audio data added by the adding unit 1203 on a recording medium. At this time, in order to further reduce the recording capacity, an audio compression process may be performed.
[0016]
The DTMF detection unit 1206 detects a DTMF code generated during communication and notifies the information channel recording unit 1204. The information channel recording unit 1204 records the DTMF code detected by the DTMF detection unit 1206 as an index together with the audio data added by the addition unit 1203. A recorded call can be searched using the recorded DTMF code as a key.
[0017]
The call control detection unit 1205 detects signals such as start and end of a call from the separated signal channels in the network side reception unit 1201 and the terminal side reception unit 1202.
[0018]
Here, in the communication system using ISDN, a sequence example from call setting to disconnection / release in one call between the communication network 102 and the terminal 105 is shown in FIG.
[0019]
As shown in this figure, when the communication network 102 transmits a call setting message SETUP (step 401), the terminal 105 receives the call setting and transmits a call setting reception message CALL PROCEEDING to the communication network (step 402).
[0020]
The incoming terminal 105 makes a call and transmits a call message ALERTING notifying that the call is in progress to the caller terminal 105A via the communication network 102 (step 403).
[0021]
When the terminal 105 responds to the PBX 104, the PBX 104 transmits a response message CONNECT to the communication network 102 (step 404).
[0022]
Upon receiving the response message CONNECT, the communication network 102 transmits a response confirmation message CONNECTACK (step 405). At this point, the terminal 105 is connected to the partner terminal 105A via the communication network 102. Information is transmitted and received (step 406).
[0023]
Taking a case where the line is disconnected from the other terminal 105A as an example, the exchange at the time of disconnection will be described below.
[0024]
First, when the disconnect message DISCONNECT of the partner terminal 105A arrives via the communication network 102 (step 407), a release message RELEASE is transmitted from the PBX 104 side, and the line is disconnected (step 408).
[0025]
Thereafter, the communication network 102 transmits a release completion message RELEASECOMPLETE to the terminal 105 (step 409).
[0026]
The call control detection unit 205 detects such a sequence. As a result, the call control detection unit 1205 can issue a recording start instruction to the information channel recording unit 1204 when receiving the response message CONNECT, and a recording stop instruction when receiving the release message RELEASE. In accordance with this instruction, the information channel recording unit 1204 records a call.
[0027]
In the method disclosed in Japanese Patent Laid-Open No. 2002-57788, the DTMF code is input by the operator via the push button of the terminal at the timing after the disconnect message DISCONNECT at step 407 (step 410). The DTMF detection unit 1206 detects the input DTMF code, and the information channel recording unit 1204 records it together with the call file consisting of voice data.
[0028]
[Problems to be solved by the invention]
However, in the method disclosed in Japanese Patent Laid-Open No. 2002-57788, the input of the DTMF code is performed at the timing after the disconnect message DISCONNECT (step 407), that is, after the other party puts the handset after the call is finished. Is called. At this time, the communication network 102 outputs a busy tone on the information channel because it is after the call termination disconnect message DISCONNECT has been sent.
[0029]
That is, the DTMF signal input by the operator is output from the adder 1203 simultaneously with the busy tone and input to the information channel recording unit 1204. For this reason, the DTMF signal may cause interference with the busy tone.
[0030]
Further, in the method disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 2002-57788, the adder 1203 uses voice data from the communication network 102 (hereinafter referred to as network-side voice data) and voice data from the terminal 105 (hereinafter referred to as “network-side voice data”). , Referred to as terminal side audio data) is fixed at 1: 1 and cannot be varied. Therefore, depending on the level ratio (amplitude ratio) between the DTMF signal and the busy tone, the DTMF code may be erroneously detected or detected.
[0031]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique for increasing the detection rate of a DTMF code in a call recording apparatus. In addition, by using this technology, the DTMF code can be reliably recorded together with the voice data, and the recorded voice data can be surely searched by the DTMF code.
[0032]
[Means for Solving the Problems]
DTMF code error detection or detection leakage occurs when the level ratio of the DTMF signal and the busy tone exceeds the detectable range, or when the DTMF signal and the busy tone cause interference. Therefore, in the present invention, in the call recording apparatus, the DTMF code can be reliably detected by improving the addition process of the network side voice data and the terminal side voice data.
[0033]
That is, the level ratio between the DTMF signal and the busy tone at the time of detecting the DTMF code is detected, and based on the level ratio, the addition ratio is controlled by the adding unit so that the level ratio falls within a detectable range. Alternatively, at the time of detecting the DTMF code, the addition unit controls the addition ratio of both so that the busy tone can be cut off.
[0034]
For example, a call recording apparatus that is installed between a terminal and a network and records a call between the terminal and another terminal that is performed via the network, the data being transmitted from the network to the terminal Network side receiving means for separating the received data into call control information and call data, and the terminal side receiving the data transmitted from the terminal to the network and separating it into the call control information and the call data A voice signal (hereinafter referred to as a network-side voice signal) included in the call data separated by the reception means and the network-side reception means; and a voice signal (hereinafter referred to as a voice signal included in the call data separated by the terminal-side reception means). Terminal unit voice signal), a call data recording unit for recording the signal added by the adding unit, the call control information separated by the network side receiving unit, and the network A call control detecting means for controlling the call data recording means by a call control signal included in each of the call control information separated by the receiving means, and a signal for identifying the call from the signals added by the adding means (hereinafter referred to as the call control detecting means) Call specific signal detecting means for extracting the call specific signal) and the called terminal included in the call data separated by the network side receiving means disconnects the call in accordance with the control of the call control detecting means Network-side maximum value detecting means for detecting the maximum level of a signal indicating that this is a signal (hereinafter referred to as a signal after disconnection), and call data separated by the terminal-side receiving means according to the control of the call control detecting means A terminal-side maximum value detecting means for detecting a maximum level of the included call specifying signal; and a call-predicting signal that can be detected by the call specifying signal detecting means. A level ratio between the predetermined call identification signal and the post-disconnection signal is maintained, and the post-disconnection detected by the network-side maximum value detection unit and the terminal-side maximum value detection unit based on the level ratio Adding ratio determining means for determining an adding ratio between the network side voice signal and the terminal side voice signal in the adding means using the maximum level of the signal and the maximum level of the call specific signal; A call recording device is provided.
[0035]
A call recording device installed between a terminal and a network and recording a call between the terminal and another terminal performed via the network, the data being transmitted from the network to the terminal Network side receiving means for separating the received data into call control information and call data, and the terminal side receiving the data transmitted from the terminal to the network and separating it into the call control information and the call data A voice signal (hereinafter referred to as a network-side voice signal) included in the call data separated by the reception means and the network-side reception means; and a voice signal (hereinafter referred to as a voice signal included in the call data separated by the terminal-side reception means). Terminal unit voice signal), a call data recording unit for recording the signal added in the addition unit, the call control information separated by the network side reception unit, and the network side The call control detecting means for controlling the call data recording means and the adding means by the call control signal included in each of the call control information separated in the communication means, and specifying the call from the signals added in the adding means A call specifying signal detecting means for extracting a signal to be transmitted (hereinafter referred to as a call specifying signal), and the adding means indicates that the call is requested to be disconnected according to an instruction from the call control detecting means The call recording apparatus is characterized in that the addition ratio of the network-side audio signal and the terminal-side audio signal is set to 0: 1 from when the call is received until the call is released.
[0036]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of the present invention will be described below with reference to the drawings.
[0037]
An example of an ISDN communication system to which the call recording apparatus of the present embodiment is applied is basically the same as that shown in FIG. 1 described above, and a call recording apparatus 101A is placed in place of the call recording apparatus 101.
[0038]
Further, in the ISDN communication system to which the call recording apparatus 101A of the present embodiment is applied, an example of a sequence from call setting to disconnection / release between the communication network 102 and the terminal 105 is basically the one shown in FIG. It is the same. For this reason, it is not described here again. The reference numbers and the like used in FIGS. 1 and 4 are used as they are in the following.
[0039]
Next, FIG. 2 shows functional blocks of the call recording apparatus 101A in the present embodiment.
[0040]
As shown in the figure, the call recording device 101A in the present embodiment includes a network side reception unit 201, a terminal side reception unit 202, an addition unit 203, an information channel recording unit 204, a call control detection unit 205, A DTMF detection unit 206, a network-side maximum value detection unit 207, a terminal-side maximum value detection unit 208, and an addition ratio determination unit 209 are provided.
[0041]
Here, the network side receiving unit 201, the terminal side receiving unit 202, the adding unit 203, the information channel recording unit 204, the call control detecting unit 205, and the DTMF detecting unit 206 are each described in the prior art. The network recording unit 1201, the terminal side receiving unit 1202, the adding unit 1203, the information channel recording unit 1204, the call control detecting unit 1205, and the DTMF detecting unit 1206 of the call recording device 101 are basically the same. It has a function.
[0042]
The network-side maximum value detection unit 207 is connected from the communication network 102 side until the call control detection unit 205 detects a release RELEASE message after the call control detection unit 205 detects the release RELEASE message in the sequence of one call shown in FIG. The signal level of the input busy tone is detected, the maximum value of the detected signal level is held, and the addition ratio determination unit 209 is notified.
[0043]
Similarly, the network-side maximum value detection unit 207 also sets the busy tone signal level during the next call (between the time when the call control detection unit 205 detects the disconnect DISCONNECT message and the time when the release RELEASE message is detected). To detect. When the detected signal level is higher than the signal level currently held by the network side maximum value detection unit 207, the held signal level is updated to the detected signal level.
[0044]
The network side maximum value detection unit 207 does not update the held signal level when the detected signal level is lower than the held signal level.
[0045]
The terminal-side maximum value detection unit 208 starts from the terminal 105 side after the call control detection unit 205 detects a disconnect DISCONNECT message until a release RELEASE message is detected in the sequence of one call shown in FIG. It detects the signal level of the input DTMF signal, holds the maximum value of the detected signal level, and notifies the addition ratio determination unit 209.
[0046]
The terminal-side maximum value detection unit 208 similarly detects the level of the DTMF signal during the next call. When the detected signal level is higher than the signal level currently held by the terminal-side maximum value detection unit 208, the held signal level is updated to the detected signal level.
[0047]
Note that the terminal-side maximum value detection unit 208 does not update the held signal level when the detected signal level is lower than the held signal level.
[0048]
The call control detection unit 205 has the following functions in addition to the functions described in the prior art. When the call control detection unit 205 detects the disconnect message, it instructs the network side maximum value detection unit 207 and the terminal side maximum value detection unit 208 to detect the maximum value of the subsequent voice data. When the release message is detected, the network side maximum value detection unit 207 and the terminal side maximum value detection unit 208 are instructed to end acquisition of the maximum value.
[0049]
The addition ratio determination unit 209 holds in advance signal level ratio data that allows the DTMF detection unit 206 to distinguish between a DTMF signal and a busy tone, and uses this data to detect the network-side maximum value detection unit 207 and the terminal-side maximum value detection. The ratio (addition ratio) at which the DTMF signal and the busy tone are added is determined by the adder 203 so that the signal level ratio of both signals input from the unit 208 is equal to or less than the level ratio that can be distinguished by the DTMF detector 206. To do.
[0050]
As described in the prior art, the DTMF detection unit 206 detects a DTMF signal from the addition signal obtained by adding the busy tone to the DTMF signal output from the addition unit 203. When the ratio between the signal level of the DTMF signal and the signal level of the busy tone is greater than a predetermined signal level ratio, the DTMF detection unit 206 may not be able to detect the DTMF signal accurately or may not be able to detect the DTMF signal at all. In such a case, the DTMF detection unit 206 notifies the information channel recording unit 204 of an incorrect DTMF code, or cannot notify the DTMF code.
[0051]
Here, FIG. 3A shows a signal level ratio at which a DTMF signal can be detected, and FIG. 3B shows a signal level ratio at which a false detection of the DTMF signal occurs or cannot be detected. As shown in this figure, for example, when the ratio of the signal level of the DTMF signal to the signal level of the busy tone is 1: N and N = 2, the DTMF signal can be detected, and N is more than that (here, N = In the case where detection is not possible in 3), the addition ratio determination unit 209 determines the maximum signal level of the DTMF signal input from the terminal-side maximum value detection unit 208 and the busy tone signal level input from the network-side maximum value detection unit 207. When the ratio to the maximum value is 1: n, the addition ratio for adding the DTMF signal and the busy tone is determined so that n = 2 or less.
[0052]
The addition ratio determination unit 209 transmits the determined addition ratio to the addition unit 203, and the addition unit 203 that has received the addition ratio 203 uses the addition ratio from the next call to use the network side reception unit 201 and the terminal side reception unit 202. The signals input from are added.
[0053]
In actual operation, the addition ratio determination performed by the addition ratio determination unit 209 is performed during a test before the start of system operation. If it is determined during the test, it is possible to record at an appropriate addition ratio for all calls to be recorded.
[0054]
Further, if the determination of the addition ratio is continued even during operation, it is possible to adjust to the optimal addition ratio in accordance with the change over time of the system.
[0055]
By using the system as described above, when a large number of operators such as call centers use the same call recording device 101A, the operator can accurately detect the DTMF code to be recorded as an index at the end of the call. Become. As a result, the DTMF code can be reliably recorded together with the audio data.
[0056]
This makes it possible to search using the DTMF code as a key when reproducing the call recording device, and it becomes easier to obtain desired audio data.
[0057]
Next, a second embodiment of the present invention will be described below with reference to the drawings.
[0058]
An example of an ISDN communication system to which the call recording apparatus of this embodiment is applied is basically the same as that shown in FIG. 1 described above, and a call recording apparatus 101B is placed in place of the call recording apparatus 101.
[0059]
Also, in the ISDN communication system to which the call recording apparatus 101B of this embodiment is applied, an example of a sequence from call setting to disconnection / release between the communication network 102 and the terminal 105 is basically as shown in FIG. It is the same. For this reason, it is not described here again. The reference numbers and the like used in FIGS. 1 and 4 are used as they are in the following.
[0060]
Next, FIG. 5 shows functional blocks of the call recording apparatus 101B in the present embodiment.
[0061]
As shown in the figure, the call recording apparatus 101B in the present embodiment includes a network side reception unit 301, a terminal side reception unit 302, an addition unit 303 with an addition ratio changing function, an information channel recording unit 304, and call control. A detection unit 305 and a DTMF detection unit 306 are provided.
[0062]
The network side reception unit 301, the terminal side reception unit 302, the information channel recording unit 304, and the DTMF detection unit 306 are respectively the network side reception unit 1201 and the terminal side of the call recording device 101 described in the related art. The reception unit 1202, the information channel recording unit 1204, and the DTMF detection unit 1206 have basically the same functions.
[0063]
Here, in the sequence shown in FIG. 4, the input of the DTMF code for call identification is normally performed between the disconnect message DISCONNECT and the release message RELEASE at the end of the call.
[0064]
Therefore, in the present embodiment, the addition unit 303 with addition ratio change function blocks the network side voice data from the detection of the disconnect message DISCONNECT until the detection of the release message RELEASE, and the terminal side voice including the DTMF code. By outputting only the data from the addition unit 303 with the addition ratio change function, the accuracy of detecting the DTMF code from the audio data output from the addition unit 303 with the addition ratio change function is increased.
[0065]
In addition to the function of the conventional call control detection unit 1205, the call control detection unit 305 in the present embodiment is connected to the addition unit 303 with addition ratio changing means when a specific message is detected in the sequence shown in FIG. It has a function of instructing the addition ratio between the audio data and the terminal-side audio data.
[0066]
In this embodiment, for example, when the response message CONNECT is detected, an instruction is given to add the network side voice data and the terminal side voice data at a ratio of 1: 1, and when the disconnect message DISCONNECT is detected, An instruction is given to add both data at a ratio of 0: 1. Next, when a release message RELEASE is detected, an instruction is given to add both data at a ratio of 1: 1.
[0067]
By controlling the addition rate in this way, the addition unit 303 with addition rate changing means does not add the network side voice data from the time when the disconnect message DISCONNECT is detected until the release message RELEASE is detected. Only audio data can be output as an addition result.
[0068]
FIG. 6 shows the state of the addition ratio in each sequence in the above example.
[0069]
In this embodiment, the call control detection unit 305 is set to issue an instruction to change the addition ratio of both data to 1: 1 when the response message CONNECT is detected and when the release message RELEASE is detected. ing. This is so that even if one of the messages is lost due to disturbance of the call control procedure, it can be dealt with. Of course, either one of the timings of issuing an instruction to change the addition ratio of both data to 1: 1 may be used.
[0070]
When the addition unit 303 with addition ratio changing function receives the above-described addition ratio instruction from the call control detection unit 305, the network-side voice data and terminal-side voice data are received until the next addition ratio instruction is received. Are added at the specified ratio and output.
[0071]
As described above, in this embodiment, the network side voice data is cut off during a period in which there is a high possibility that the DTMF code to be recorded as an index by the operator at the end of the call. For this reason, there is less possibility that the DTMF code cannot be detected due to interference with the busy tone included in the network side voice data. It becomes possible to detect well. As a result, the DTMF code can be reliably recorded together with the audio data.
[0072]
This makes it possible to search using the DTMF code as a key when reproducing the call recording device, and it becomes easier to obtain desired audio data.
[0073]
Further, in the call recording device of each of the embodiments described above, the call recording device includes a call control detection unit that detects a specific message included in the call control information, and the call control detection unit performs information according to the detected message. The channel recording unit is configured to instruct the start and stop of recording of audio data.
[0074]
Here, a device that performs processing related to call control, such as a CTI (Computer Telephony Integration) system, is configured separately from the call recording device, and the call recording device obtains a signal from the device and receives information from the information channel recording unit. Control of starting and stopping recording may be performed.
[0075]
That is, a device installed separately from a call recording device such as DSU or PBX installed between the terminal and the network detects a specific message from the call control information of the signal channel, and detects a specific message. When a call recording device has a function of outputting a signal notifying that a specific message of call control information is detected to the call recording device, the call recording device detects a specific message of call control information from these devices. The information channel recording unit may be configured to start and stop recording of the information channel when a signal to the effect is received.
[0076]
In this case, the network side receiving unit has a function of receiving data transmitted from the network side to the terminal side and outputting the information channel to the information channel recording unit, and the terminal side receiving unit transmits from the terminal side to the network side. It is only necessary to have a function of receiving the received data and outputting the information channel to the information channel recording unit.
[0077]
In each of the above embodiments, an ISDN line has been described as an example of a communication line, but the application of the present invention is not limited to this. For example, the transmission data and the reception data may be transferred by using different channels via the network and can be received. For example, the present invention can be applied to Voice Over IP.
[0078]
Further, the configuration of the present invention is not limited to a call recording device, but can be applied to all systems using DTMF codes such as various public services, corporate customer services, or an automatic voice response system used in a telephone voting system. Can be applied.
[0079]
【The invention's effect】
In the ISDN line call recording device, it is possible to reliably perform a call search using a call identification code by DTMF input during a call.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating an example of a communication system.
FIG. 2 is a functional block diagram of a call recording apparatus to which the first embodiment of the present invention is applied.
FIG. 3 is a diagram for explaining whether or not a DTMF signal and a busy tone can be detected.
FIG. 4 is a diagram showing a sequence during one call in a communication system using ISDN.
FIG. 5 is a functional block diagram of a call recording apparatus to which a second embodiment of the present invention is applied.
FIG. 6 is a diagram illustrating a state of an addition ratio in each sequence during a call.
FIG. 7 is a functional block diagram of a conventional ISDN line call recording device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 101 ... Call recording apparatus, 102 ... ISDN line network, 103 ... DSU, 104 ... PBX, 105 ... Terminal, 201 ... Network side receiving part, 202 ... Terminal side reception , 203... Addition unit, 204... Information channel recording unit, 205... Call control information detection unit, 206... DTMF detection unit, 207.・ Terminal side maximum value detector

Claims (8)

A call recording device that is installed between a terminal and a network and records a call between the terminal and another terminal performed via the network,
Network-side receiving means for receiving data transmitted from the network to the terminal and extracting call data included in the data;
Terminal-side receiving means for receiving data transmitted from the terminal to the network and extracting call data included in the data;
A voice signal (hereinafter referred to as a network side voice signal) included in the call data extracted by the network side receiving means and a voice signal (hereinafter referred to as a terminal side voice signal) included in the call data extracted by the terminal side receiving means. Adding means for adding
Call data recording means for recording the signal added in the adding means;
A call specifying signal detecting means for extracting a signal specifying the call (hereinafter referred to as a call specifying signal) from the signals added by the adding means;
Network-side maximum value detection for detecting a maximum level of a signal (hereinafter referred to as a signal after disconnection) indicating that the other terminal included in the call data output from the network-side receiving means is disconnected. Means,
Terminal-side maximum value detecting means for detecting the maximum level of the call specific signal included in the call data output from the terminal-side receiving means;
Control means for controlling the call data recording means, the network-side maximum value detecting means, and the terminal-side maximum value detecting means by a call control signal included in call control information transmitted between the terminal and the network; ,
The call specific signal detecting means can detect the call specific signal, holds a predetermined level ratio between the call specific signal and the disconnected signal, and detects the network-side maximum value based on the level ratio. Using the maximum level of the signal after disconnection and the maximum level of the call specific signal respectively detected by the means and the terminal side maximum value detection means, the network side voice signal and the terminal side voice signal in the addition means A call recording apparatus comprising: an addition ratio determining means for determining an addition ratio. The call recording device according to claim 1,
The network side receiving means further extracts call control information included in the received data, and outputs to the control means,
The call recording apparatus, wherein the terminal-side receiving means further extracts call control information contained in the received data and outputs the call control information to the control means. The call recording device according to claim 1 or 2,
The call recording apparatus, wherein the signal after disconnection is a busy tone. A call recording device that is installed between a terminal and a network and records a call between the terminal and another terminal performed via the network,
Network-side receiving means for receiving data transmitted from the network to the terminal and extracting call data included in the data;
Terminal-side receiving means for receiving data transmitted from the terminal to the network and extracting call data included in the data;
A voice signal (hereinafter referred to as a network side voice signal) included in the call data extracted by the network side receiving means and a voice signal (hereinafter referred to as a terminal side voice signal) included in the call data extracted by the terminal side receiving means. Adding means for adding
Call data recording means for recording the signal added in the adding means;
Control means for controlling the call data recording means and the adding means by a call control signal included in call control information transmitted between the terminal and the network;
A call specifying signal detecting means for extracting a signal specifying the call (hereinafter referred to as a call specifying signal) from the signals added by the adding means;
The call recording apparatus according to claim 1, wherein the adding means switches the addition ratio of the network side voice signal and the terminal side voice signal between 1: 1 and 0: 1 in accordance with an instruction from the control means. The call recording device according to claim 4, wherein
The network side receiving means further extracts call control information included in the received data, and outputs to the control means,
The terminal-side receiving means further extracts call control information included in the received data and outputs the call control information to the control means,
The adding means receives the signal indicating that the call is requested to be disconnected included in the call control information until the call is released until the network side voice signal and the terminal side voice signal are A call recording apparatus characterized in that the addition ratio is 0: 1. The call recording device according to claim 1, 2, 3, 4, or 5,
The call recording apparatus, wherein the call specific signal is a DTMF (Dual Tone Multi-Frequency) signal and is input by an operator of the terminal. A call recording method for recording a call between the terminal and another terminal performed between the terminal and a network via the network,
Network side data separation step of receiving data transmitted from the network to the terminal and separating the data into call control information and call data;
Receiving data transmitted from the terminal to the network, and separating the data into the call control information and the call data;
Included in the call data separated in the network side data separation step according to the call control information separated in the network side data separation step and the control information obtained by the call control information separated in the terminal side data separation step Detecting a maximum level of the signal after disconnection from a signal indicating that the other terminal has disconnected the call (hereinafter referred to as a signal after disconnection);
Detecting a maximum level of a signal (hereinafter referred to as a call specifying signal) for specifying the call included in the call data separated in the terminal-side data separation step according to the control information;
Call data separated in the network-side data separation step from the maximum level of the post-disconnect signal and the maximum level of the call specific signal based on data indicating a range in which the call specific signal can be detected that is held in advance. The sum ratio for adding the voice signal (hereinafter referred to as the network side voice signal) included in the voice signal and the voice signal (hereinafter referred to as the terminal side voice signal) included in the call data separated in the terminal side data separation step is calculated. And steps to
Detecting the call specific signal from the network-side voice signal and the terminal-side voice signal added at the addition ratio;
And recording the detected call specific signal together with the network-side voice signal and the terminal-side voice signal added at the addition ratio. A call recording method for recording a call between the terminal and another terminal performed between the terminal and a network via the network,
Network side data separation step of receiving data transmitted from the network to the terminal and separating the data into call control information and call data;
Receiving data transmitted from the terminal to the network, and separating the data into the call control information and the call data;
Included in the call data separated in the network side data separation step according to the call control information separated in the network side data separation step and the control information obtained by the call control information separated in the terminal side data separation step Determining an addition ratio of voice data (hereinafter referred to as a network-side voice signal) and voice data (hereinafter referred to as a terminal-side voice signal) included in the call data separated in the terminal-side data separation step;
Adding the network side audio signal and the terminal side audio signal according to the addition ratio;
Detecting a signal specifying the call (hereinafter referred to as a call specifying signal) from the network-side audio signal and the terminal-side audio signal added at the addition ratio;
And recording the detected call specific signal together with the network-side voice signal and the terminal-side voice signal added at the addition ratio.

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