JP2002204258A - Real time information receiver and method for eliminating delay fluctuation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restore absorbable fluctuating time delay on a receiving side even when there are variations in packet transmission delay time. SOLUTION: A real time information packet which is received by a packet receiving part 101 and transmitted at a fixed interval and with a packet length is temporarily stored in a fluctuation absorption buffer 102. Meanwhile, a stored data quantity deciding means 104 decides a data amount stored in the buffer 102, and in the case that a period when the stored data amount falls below a preset threshold lasts for a fixed period, the decoding of the data stored in the buffer 102 by a decoding part 103 is interrupted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a real-time information receiving apparatus connected to a packet network in which a transmission delay can fluctuate and a method for removing delay fluctuation.

[0002]

2. Description of the Related Art At present, packet-switched networks represented by Ethernet and the like have become widespread, and data communication with high real-time properties such as voice communication provided in conventional circuit-switched networks has been realized by packet switching. There is an increasing demand for realizing this in a network of a system. However, in a packet-switched network, a delay fluctuation occurs in which a transmission delay time from when a transmitting side transmits a packet to when the packet reaches a receiving side fluctuates.

For this reason, when realizing highly real-time data communication in a packet-switched network, even if the arrival of a packet is temporarily delayed due to delay fluctuation, data loss is prevented on the receiving side. A method is used in which the packet is temporarily stored in a fluctuation absorbing buffer constituted by a FIFO (first-in first-out memory), and the packet is processed after a predetermined time (delay fluctuation absorbing time) has elapsed. For this reason,
If the transmitting side transmits fixed-length packets at fixed intervals, the average of the time from when a packet is received until it is processed is equal to the delay fluctuation absorption time, and the average amount of data stored in the fluctuation absorption buffer is There is a feature that the data amount is equivalent to the delay fluctuation absorption time.

[0004]

However, in the conventional real-time information receiving apparatus using the above-mentioned fluctuation absorbing buffer, the time which elapses by the fluctuation absorbing time after receiving the first packet at the start of communication is measured by the fluctuation absorbing buffer. Then, the data in the fluctuation buffer is sequentially processed at the encoding speed of the real-time information. Therefore, if the transmission delay time of the first packet is shorter than the subsequent packets,
That is, if the first packet arrives earlier than the subsequent packets, a large amount of data stored in the fluctuation buffer is processed until the subsequent packet arrives, and the data stored in the fluctuation absorption buffer is processed. The amount is reduced. As a result, the time from reception to data processing becomes smaller than the delay fluctuation absorption time, and there is a problem that the time of the delay fluctuation that can be absorbed on the receiving side is reduced.

In order to recover the amount of data stored in the fluctuation absorbing buffer, it is necessary to interrupt data processing on the receiving side. However, simply interrupting affects the reproduction of real-time information. There is a problem that.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and provides a real-time information receiving apparatus capable of recovering a delay fluctuation time that can be absorbed by a receiving side even when a packet transmission delay time varies. The purpose is to do.

[0007]

According to the present invention, there is provided a real-time information receiving apparatus, comprising: a packet receiving section for receiving real-time information packets transmitted at a constant interval and a packet length; and temporarily storing the real-time information packets. A fluctuation absorbing buffer, a stored data amount determining means for determining an amount of data stored in the fluctuation absorbing buffer, and a time during which the stored data amount determined by the stored data amount determining means falls below a preset threshold is fixed. And a decoding unit for interrupting the decoding of the data stored in the fluctuation absorbing buffer when the time continues.

According to this configuration, the amount of data accumulated in the fluctuation absorbing buffer is reduced, and as a result, even if the time from reception to data processing becomes shorter than the delay fluctuation absorbing time, By monitoring whether or not the data amount is below the threshold continuously, this is detected and decoding is temporarily stopped. As a result, it is possible to increase the amount of data in the fluctuation absorbing buffer and, consequently, increase the time from when a packet is received to when it is decoded, thereby recovering the delay fluctuation time that can be absorbed on the receiving side.

Further, the invention of a real-time information receiving apparatus according to the present invention comprises a packet receiving section for receiving real-time information packets transmitted at a fixed interval and a packet length, and a fluctuation absorbing buffer for temporarily storing the real-time information packets. And, after the start of communication, a reception packet counter that counts the number of reception packets that is the total number of the real-time information packets received by the packet reception unit, and reception within a fixed time from the point in time when reception was started by the packet reception unit When the number of received packets is smaller than a preset threshold value, a decoding unit is provided which interrupts decoding of data accumulated in the fluctuation absorbing buffer.

According to this configuration, the amount of data stored in the fluctuation absorbing buffer is reduced, and as a result, even if the time from reception to data processing becomes shorter than the delay fluctuation absorbing time, it can be maintained within a fixed time. By monitoring whether the number of arriving packets is below the threshold, this is detected and decoding is temporarily stopped. As a result, it is possible to increase the amount of data in the fluctuation absorbing buffer and, consequently, increase the time from when a packet is received to when it is decoded, thereby recovering the delay fluctuation time that can be absorbed on the receiving side.

Further, in the invention of the real-time information receiving apparatus according to the present invention, the decoding unit may be configured such that when the accumulated data amount falls below a preset threshold for a predetermined period of time, When the number falls below a preset threshold, the decoding of the data stored in the fluctuation absorbing buffer is interrupted, and in other cases, the decoding of the data stored in the fluctuation absorbing buffer is performed. A decoding processing unit, a silence output unit that outputs silence data when the decoding processing unit interrupts the decoding process, and silence data from the silence output unit when the decoding processing unit interrupts the decoding process. And a signal selection unit for selecting decoded data from the decoding processing unit when decoding processing is being performed.

According to this configuration, the amount of data stored in the fluctuation absorbing buffer decreases, and as a result, when the time from reception to data processing becomes shorter than the delay fluctuation absorbing time, decoding is temporarily performed. By reproducing the silence data from the silence output unit when the decoding is stopped, the unnaturalness at the time of stopping the decoding can be reduced.

[0013] Also, in the invention of the real-time information receiving apparatus of the present invention, the decoding unit may be configured such that when the time during which the amount of accumulated data falls below a preset threshold has continued for a predetermined time, or when the received packet If the number is less than a preset threshold value, the decoding of the data stored in the fluctuation absorbing buffer is interrupted, and otherwise, the decoding of the data stored in the fluctuation absorbing buffer is performed. A decoding processing unit, a sound source unit that outputs various audio data when the decoding processing unit interrupts the decoding process,
A signal selection unit that selects audio data from the sound source unit when the decoding processing unit interrupts the decoding process, and selects decoded data from the decoding processing unit when performing the decoding process. Is provided.

According to this configuration, the amount of data stored in the fluctuation absorbing buffer decreases, and as a result, when the time from reception to data processing becomes shorter than the delay fluctuation absorbing time, decoding is temporarily performed. By reproducing the sound from the sound source section when the decoding is stopped, the unnaturalness at the time of stopping the decoding can be reduced.

[0015] In the invention of the real-time information receiving apparatus of the present invention, the decoding unit may be configured such that when the time during which the amount of accumulated data falls below a preset threshold has continued for a certain period of time, or when a received packet received within a certain period of time, A decoding notification timer that repeats outputting a decoding stop instruction for a fixed period of time at a fixed period when the number is less than a preset threshold, and the decoding processing unit is configured to absorb the fluctuation when the decoding stop instruction is output. While the decoding of the data stored in the buffer is interrupted, the decoding of the data stored in the fluctuation absorbing buffer is performed when the decoding stop instruction has not been output, and the signal selecting unit includes: When a decoding stop instruction is output, data is selected from the silence output unit or the sound source unit, and when not output, decoding from the decoding processing unit is selected. A configuration to select the data only.

According to this configuration, decoding is stopped when the amount of data stored in the fluctuation absorbing buffer decreases, and as a result, the time from reception to data processing becomes shorter than the delay fluctuation absorbing time. In such a case, decoding is stopped repeatedly for a short time. As a result, even when the data in the fluctuation absorbing buffer is significantly reduced,
It is possible to reduce the influence on communication quality due to stopping decoding for a long time.

Further, in the invention of the real-time information receiving apparatus according to the present invention, the decoding unit may be configured such that when the accumulated data amount falls below a preset threshold for a predetermined period of time or a received packet received within a predetermined period of time. A decoding notification timer that repeats outputting a decoding stop instruction for a fixed period of time at a fixed period when the number is less than a preset threshold value, and a decoding notification timer for outputting data stored in the fluctuation absorption buffer when the decoding stop instruction is output. A decoding processing unit that executes decoding of data accumulated in the fluctuation absorption buffer when the decoding is stopped and the decoding stop instruction is not output;
While receiving the decoded data from the decoding processing unit, when the decoding stop instruction is output, the decoded data is decoded immediately before the decoding stop instruction is output and when the decoding stop instruction is output. An interpolation output calculator that outputs interpolation data between decoded data obtained by decoding the immediately preceding undecoded data, and interpolation data from the interpolation output calculator when the decoding stop instruction is output. And a signal selection unit for selecting decoded data from the decoding processing unit when the data has not been output.

According to this configuration, decoding is stopped when the amount of data stored in the fluctuation absorbing buffer decreases, and as a result, the time from reception to data processing becomes shorter than the delay fluctuation absorbing time. In this case, by reproducing the interpolation data from the interpolation output calculation unit, it is possible to reduce unnaturalness when decoding is stopped. Also,
By repeatedly stopping decoding for a short time, even when the data in the fluctuation absorbing buffer is significantly reduced, the influence on communication quality due to stopping decoding for a long time can be reduced.

Further, in the invention of the real-time information receiving apparatus according to the present invention, the decoding unit may be configured such that when the accumulated data amount falls below a preset threshold for a predetermined time or a received packet received within a predetermined time. When the number is less than a preset threshold, and when a silence portion is detected from the input decoded data, a silence detection unit that outputs a decoding stop instruction and the decoding stop instruction are output. A decoding processing unit for interrupting the decoding of the data stored in the fluctuation absorbing buffer in the case where the data is not output, and decoding the data stored in the fluctuation absorbing buffer when the data is not output. A silence output unit that outputs silence data when the unit interrupts the decoding process, and selects data from the silence output unit when the decoding stop instruction is output. That one employs a configuration having a, a signal selection unit for selecting data from the decoding unit when not output.

According to this configuration, decoding is stopped when the amount of data stored in the fluctuation absorbing buffer is reduced, and as a result, the time from reception to data processing becomes shorter than the delay fluctuation absorbing time. In this case, the decoding is stopped only when there is no sound. As a result, it is possible to reduce the influence on communication quality caused by stopping decoding.

Further, in the invention of the real-time information receiving apparatus according to the present invention, the decoding unit may be configured such that when the time during which the amount of accumulated data falls below a preset threshold has continued for a predetermined time, or when a received packet received within a predetermined time has been received. A case in which the number is below a preset threshold value, and a case in which a silence detection unit that outputs a silence detection signal when a silence portion is detected from the input decoded data, and a case in which the silence detection signal is output. A decoding notification timer that repeats the output of the decoding stop instruction for a certain period of time at a fixed cycle, and, while the decoding stop instruction is output, interrupts the decoding of the data stored in the fluctuation absorption buffer, and outputs the data. A decoding processing unit that decodes data stored in the fluctuation absorbing buffer when the decoding processing unit interrupts decoding processing. And a signal selection unit that selects data from the silence output unit when the decoding stop instruction is output, and selects data from the decoding processing unit when the data is not output. Are adopted.

According to this configuration, decoding is stopped when the amount of data stored in the fluctuation absorbing buffer decreases, and as a result, the time from reception to data processing becomes shorter than the delay fluctuation absorbing time. In this case, the decoding is stopped only when there is no sound. As a result, it is possible to reduce the influence on communication quality caused by stopping decoding. In addition, by repeatedly stopping the decoding for a short time, even when the data in the fluctuation absorbing buffer is significantly reduced, the influence on the communication quality caused by stopping the decoding for a long time can be reduced.

A communication device according to the present invention reproduces audio data decoded by a real-time information receiving device according to any one of claims 1 to 8 and a decoding unit of the real-time information receiving device. A reproducing unit, an encoding unit that encodes the input audio, and a packet transmission unit that divides the data encoded by the encoding unit into packets of a fixed length and transmits the packets at predetermined intervals. The configuration provided is adopted.

With this configuration, the effect of the real-time information receiving device according to any one of the first to eighth aspects can be obtained in a communication device.

According to the invention of a real-time information communication system according to the present invention, a real-time information receiving apparatus according to any one of claims 1 to 8, a packet network having a variable transmission delay, and an encoded real-time information And a real-time information transmitting apparatus for transmitting the packet to the packet network at fixed intervals and a packet length.

Further, the method of removing delay fluctuation according to the present invention comprises the steps of: receiving a real-time information packet transmitted at a fixed interval and a packet length; and temporarily storing the real-time information packet in a fluctuation absorbing buffer.
Determining the amount of data stored in the fluctuation absorbing buffer; and decoding the data stored in the fluctuation absorbing buffer when the determined stored data amount falls below a preset threshold for a certain period of time. Interrupting the process.

Further, the method for removing delay fluctuation according to the present invention comprises the steps of: receiving a real-time information packet transmitted at a fixed interval and a packet length; and temporarily storing the real-time information packet in a fluctuation absorbing buffer.
After the start of communication, counting the number of received packets that is the total number of the received real-time information packets, and when the number of received packets received within a certain time from the start of reception is less than a predetermined threshold, Interrupting the decoding of the data stored in the fluctuation absorbing buffer.

[0028]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram showing a configuration of a real-time information receiving apparatus 100 according to Embodiment 1 of the present invention.

A real-time information receiving apparatus 10 shown in FIG.
At 0, the packet receiving unit 101 receives the real-time information packet transmitted by the opposing device via the transmission path.

The fluctuation absorbing buffer 102 includes a memory having a FIFO (First In First Out) structure for temporarily storing real-time information packets acquired from the packet receiving unit 101. After temporarily storing the real-time information packet using this memory, the delay fluctuation on the transmission path is absorbed by sequentially transferring the previously stored data to the decoding unit 103 sequentially.

The accumulated data amount judging means 104 judges whether or not the accumulated data amount acquired from the fluctuation absorbing buffer 102 is smaller than a threshold value of the accumulated data amount held by itself. Only when the accumulated data amount is smaller than the threshold value, the accumulated data amount determining unit 104 notifies the continuous monitoring timer 105 of the accumulated data amount judgment result (hereinafter, referred to as “accumulated data amount judgment result”).

The continuation monitoring timer 105 determines whether or not the notification of the storage data amount determination result from the storage data amount determination means 104 has continued for a predetermined time or more. Only when the notification of the accumulated data amount determination result has continued for a certain period of time or more, the continuation monitoring timer 105 outputs the determination result (hereinafter simply referred to as “continuation determination result”) indicating that fact.
Notify 3.

The decoding unit 103 includes the fluctuation absorbing buffer 1
Decode the real-time information packet from H.02. However, when the continuation determination result is notified from the continuation monitoring timer 105, the continuation monitoring timer 105 has a function of interrupting the acquisition of the real-time information packet from the fluctuation absorbing buffer 102 and the decoding of the acquired real-time information packet.

FIG. 2 is a block diagram showing a specific configuration of decoding section 103 of real-time information receiving apparatus 100 according to the present embodiment.

In the decoding section 103 shown in FIG. 2, the decoding processing section 201 actually determines whether the fluctuation absorbing buffer 1
Decode the real-time information packet from H.02. When the continuation determination result is notified from the continuation monitoring timer 105, the acquisition of the real-time information packet from the fluctuation absorbing buffer 102 is stopped, and the decoding process is stopped.

The silence output section 202 outputs silence data reproduced when the decoding section 201 stops decoding.

The signal selection section 203 is provided for the continuation monitoring timer 10
5, the decoded data from the decoding processing unit 201 or the silence output unit 202 according to the presence or absence of the notification of the continuation determination result.
Select one of the silent data from. When the continuation determination result is not notified from the continuation monitoring timer 105, the data from the decoding processing unit 201 is selected and output.
On the other hand, when the continuation determination result is notified from the continuation monitoring timer 105, the silent data from the silent output unit 202 is selected and output.

FIG. 3 is a block diagram showing a specific configuration of the continuous monitoring timer 105 of the real-time information receiving apparatus 100 according to the present embodiment.

In the continuation monitoring timer 105 shown in FIG. 3, the notification continuation time counter 301 indicates the time during which the storage data amount determination result from the storage data amount determination means 104 continues to be in the notification state (hereinafter, “notification continuation time”). ")
Count. The counted notification duration is output to the notification duration determination unit 302.

The notification duration determining means 302 compares the input notification duration with a preset threshold. Decoding unit 10 only when the notification duration time exceeds the threshold
3 is notified of the continuation determination result. If the notification duration does not exceed the threshold, the decoding unit 103 is not notified of the continuation determination result.

Next, the operation of the real-time information receiving apparatus 100 having the above configuration will be described with reference to FIG. FIG. 4 is a time chart for explaining the operation of the real-time information receiving apparatus 100. FIG. 4 is a timing chart showing the operation of each unit of the real-time information receiving apparatus 100 when the transmission delay of the first packet is smaller than the transmission delay of subsequent packets. In particular, FIG. Transmission / reception, Fig. 4
FIG. 4B shows a change in the amount of data in the fluctuation absorbing buffer, FIG.
FIG. 4C shows a change in the stored data determination result, and FIG.
Indicates a change in the continuation determination result.

When a real-time information packet is received from an opposite device via a transmission line, the packet receiving unit 101
Transfers the real-time information packet to the fluctuation absorbing buffer 102.

At the start of communication, the fluctuation absorbing buffer 102 stores dummy data corresponding to the delay fluctuation absorbing time. Then, receiving the first packet,
The data in the buffer is sequentially transferred to the decoding unit 103. At this time, the data in the fluctuation absorbing buffer 102 is transferred at the encoding speed for the real-time information of the decoding unit 103. For this reason, when the packet transmission delay time is in the state shown in FIG. 4A, the data amount in the fluctuation absorbing buffer 102 changes as shown in FIG. 4B.

That is, when the transmission delay of the first packet is smaller than the transmission delay of the subsequent packets, the data in the fluctuation absorbing buffer 102 is equal to the expected transfer amount until the second packet is received. More data is transferred to the decoding unit 103. Therefore, the amount of data in the fluctuation absorption buffer 102 falls below the threshold value at the point t1. Then, even when the second packet is received at the point t2, the amount of data stored in the fluctuation absorbing buffer 102 does not exceed the threshold. Further, even when the third packet is received at the point t3, the amount of data stored in the fluctuation absorbing buffer 102 does not exceed the threshold value.

During this time, the stored data amount determining means 104
The amount of data stored in the fluctuation absorption buffer 102 is obtained. Then, at time point t1, when the amount of accumulated data in the fluctuation absorbing buffer 102 falls below the threshold, the accumulated data amount determination result is notified to the continuous monitoring timer 105. 2 as described above
Since the third packet does not exceed the threshold even when the third packet is received, the accumulated data amount determination unit 104 continuously notifies the accumulated monitoring amount timer 105 of the accumulated data amount determination result.

In the continuation monitoring timer 105, the notification continuation time counter 301 starts counting the notification continuation time of the storage data amount determination result at the time point t1. The notification duration determination unit 302 compares the notification duration with a preset threshold, and notifies the decoding unit 103 of the continuation determination result when the notification duration exceeds the threshold. Here, it is assumed that the notification duration time exceeds the threshold value at the time point t4. Therefore, as shown in FIG. 4D, at time point t4, the continuation determination result is notified to decoding section 103.

Next, the operation of decoding section 103 when a packet is received at such timing will be described.

From the time when the first packet is received at point t0 until immediately before point t4, decoding section 103 has not been notified of the continuation determination result from continuation monitoring timer 105. If no notification of the continuation determination result has been received, the decryption unit 10
No. 3 considers that the amount of data stored in the fluctuation absorbing buffer 102 is not insufficient. For this reason, in the decoding unit 103, the decoding processing unit 201
From the real-time information packet at the encoding speed,
Perform decryption processing. Then, the signal selection unit 203
The decrypted data from the decryption processing unit 201 is selected and output.

Then, at a point t4, the continuous monitoring timer 105
Receiving the notification of the continuation determination result from
Deems that the amount of data stored in the fluctuation absorbing buffer 102 is insufficient. Therefore, in the decoding unit 103, the decoding processing unit 201 stops acquiring the real-time information packet from the fluctuation absorbing buffer 102,
Stop the decryption process. Therefore, the amount of data stored in the fluctuation absorbing buffer 102 is kept constant (see FIG. 4).
(State of point t4 to point t5 shown in (b)). On the other hand, the silence output unit 202 outputs silence data to the signal selection unit 203.
The signal selection unit 203 selects and outputs silence data from the silence output unit 202.

Further, when the fourth packet is received at the point t5, the amount of data stored in the fluctuation absorbing buffer 102 exceeds the threshold. At this point, the stored data amount determination means 10
No. 4 stops the notification of the accumulated data amount determination result to the continuous monitoring timer 105. In response to the stop of the notification of the accumulated data amount determination result, the continuation monitoring timer 105
The notification of the continuation determination result for No. 3 is stopped. When the notification of the continuation determination result is stopped, the decoding unit 103 restarts the decoding process.

That is, when the continuation determination result is not notified, the decoding unit 103
And obtains and decodes the real-time information packet from the device, and when the continuation determination result is notified, interrupts the acquisition and decoding of the real-time information packet and outputs silent data.

In this embodiment, the continuous monitoring timer 105
The presence or absence of the determination result indicates whether the amount of data stored in the fluctuation absorbing buffer 102 is continuously decreasing. For this reason, when the continuation determination result is notified, that is, when the decoding
If the amount of accumulated data in 2 is continuously decreasing, decoding is stopped. On the other hand, when the continuation determination result is not notified, that is, when the amount of data stored in the fluctuation absorbing buffer 102 is not continuously reduced, the decoding is performed.

As described above, according to the real-time information receiving apparatus 100 of the present embodiment, the fluctuation absorbing buffer 102
It is detected that the amount of data in the fluctuation absorption buffer 102 is constantly small because the amount of data stored in the buffer decreases and the time from when the real-time information packet is received until decoding is reduced. By interrupting the decoding of the real-time information packet, the amount of data stored in the fluctuation absorbing buffer 102 is increased, and
Increase the time from receiving a real-time information packet to decoding it. This makes it possible to recover the delay fluctuation time that can be absorbed by the receiving side.

In this embodiment, the decoding unit 103
After the decoding process is stopped, when a subsequent real-time information packet is received and the amount of data stored in the fluctuation absorbing buffer 102 exceeds a threshold value, the decoding process is restarted. However, the present invention is not limited to this. The decoding process may be restarted by any method, such as setting the time for stopping the decoding process in advance to a fixed time and restarting after the lapse of the fixed time.

In the present embodiment, as can be seen from the fact that the silent output unit 202 shown in FIG. 2 outputs silent data, audio data is used as an example of a real-time information packet. It is not limited to. Instead of audio data, image data may be communicated as real-time information packets. In this case, the silence output unit 202 outputs image data corresponding to silence data, and a sound source unit and a silence detection unit, which will be described later in the following embodiments, process image data instead of audio data. And

(Embodiment 2) In the real-time information receiving apparatus 100 according to Embodiment 1, the stored data amount determining means 104 determines the amount of data stored in the fluctuation absorbing buffer 102 so that the data in the fluctuation absorbing buffer 102 While detecting the decrease, the real-time information receiving apparatus 500 according to the second embodiment
Is different from the first embodiment in that the number of packets received within a certain time is determined to detect a decrease in the data in the fluctuation absorbing buffer 102.

FIG. 5 is a block diagram showing a configuration of a real-time information receiving apparatus 500 according to Embodiment 2 of the present invention. In the real-time information receiving apparatus 500 shown in FIG. 5, components having the same reference numerals as those in FIG. 1 have the same functions. The specific configuration of the decoding unit 103 is the same as that shown in FIG. However, in the decoding unit 103 shown in FIG. 2, the continuation determination result is replaced with a comparison determination result described later.

As shown in FIG. 5, real-time information receiving apparatus 500 according to the second embodiment is different from real-time information receiving apparatus 100 according to the first embodiment in that stored data amount determining means 104 and continuation monitoring timer 105 are replaced. Receiving packet counter 501, comparison time designation timer 502
And the real-time information receiving apparatus 100 in that the real-time information receiving apparatus 100 is provided.

The received packet counter 501 counts the number of packets received by the packet receiving section 101. The counted number of received packets is notified to the comparing means 503.

The comparison time designation timer 502 is provided by the comparing means 5
03 processing timing (comparison timing) is designated.
Specifically, the processing timing is designated when a certain time has elapsed from the time when the first packet is received.

The comparing means 503 compares the number of received packets input from the received packet counter 501 with a preset threshold value of the number of received packets. The timing designated by the comparison timing designation timer 502 is used as the timing for executing the comparison processing. Only when the number of received packets input from the received packet counter 501 is below the threshold as a result of the comparison process,
A determination result indicating this (hereinafter, referred to as “comparison determination result”) is notified to the decoding unit 103.

The decoding section 103 is the same as the real-time receiving apparatus 100 in the first embodiment,
Decode the real-time information packet from H.02. However, when the comparison determination result is notified from the comparison unit 503, a function of interrupting the acquisition of the real-time information packet from the fluctuation absorbing buffer 102 and the decoding of the acquired real-time information packet is provided.

Next, the operation of the real-time information receiving apparatus 500 having the above configuration will be described with reference to FIG. FIG. 6 is a time chart for explaining the operation of the real-time information receiving apparatus 500. FIG. 6 is a timing chart showing the operation of each unit of the real-time information receiving apparatus 500 when the transmission delay of the first packet is smaller than the transmission delay of subsequent packets. In particular, FIG. Transmission and reception, Fig. 6
FIG. 6B shows a change in the amount of data in the fluctuation absorbing buffer, FIG.
FIG. 6C shows a change in the number of packets received within a fixed time held by the comparison time designation timer 502, and FIG. 6D shows a change in the comparison determination result.

When a real-time information packet is received from the opposing device via the transmission line, similar to the first embodiment,
The packet receiving unit 101 transfers the real-time information packet to the fluctuation absorbing buffer 102. Similarly to the first embodiment, the fluctuation absorbing buffer 102 sequentially transfers the data in the fluctuation absorbing buffer 102 to the decoding unit 103 from the data accumulated first upon receiving the first real-time information packet. Therefore, when the packet transmission delay time changes at the timing shown in FIG. 6A, the data amount in the fluctuation absorbing buffer 102 changes as shown in FIG. 6B.

That is, when the transmission delay of the first packet is smaller than the transmission delay of the subsequent packets, the data in the fluctuation absorbing buffer 102 is equal to the expected transfer amount until the second packet is received. More data is transferred to the decoding unit 103. Therefore, the amount of data stored in the fluctuation absorbing buffer 102 falls below the threshold value at the point t1.
Then, even when the second packet is received at the point t2, the amount of data stored in the fluctuation absorbing buffer 102 does not exceed the threshold. Further, even when the third packet is received at the point t3, the amount of data stored in the fluctuation absorbing buffer 102 does not exceed the threshold value.

During this time, the reception packet counter 501
The packet receiving state is obtained from the packet receiving unit 101. Then, the number of packets received by the packet receiving unit 101 is counted and notified to the comparing unit 503.

The comparison time designation timer 502 starts counting for a certain period of time from the time when the first packet is received at the point t0 at the start of communication. Then, when a predetermined time has elapsed, the comparing unit 503 is notified of the designation of the comparison timing. In FIG. 6B, the time until the third packet is transmitted is set to a fixed time (points t0 to t4). For this reason, when the amount of data stored in the fluctuation absorbing buffer 102 changes as shown in FIG. 6B, the number of packets received within a certain time changes as shown in FIG. 6C.

The comparing means 503 is a timer 5 for specifying a comparison time.
The number of packets received within a certain period of time is calculated by grasping the number of packets received from the received packet counter 501 when the comparison timing is designated from 02. Further, the calculated number of received packets is compared with a preset threshold value. Then, when the number of received packets is smaller than the threshold, the result of the comparison determination is decoded.
Notify 03. Here, at the time point t4, FIG.
Since the number of received packets is less than the threshold value as shown in FIG.
Notify.

Next, the operation of decoding section 103 when a packet is received at such timing will be described.

From when the first packet is received at point t0 until immediately before point t4, the decoding unit 103
03 has not been notified of the comparison determination result. If no notification of the comparison determination result has been received, the decoding unit 103
It is assumed that the amount of data stored in the fluctuation absorbing buffer 102 is not insufficient. Therefore, in the decoding unit 103,
The decoding processing unit 201 acquires a real-time information packet from the fluctuation absorbing buffer 102 at an encoding speed, and executes a decoding process. Then, the signal selection unit 203 selects and outputs the decoded data from the decoding processing unit 201.

Then, at time point t 4, when receiving the notification of the comparison determination result from comparison means 503, decoding section 103 regards that the amount of data stored in fluctuation absorbing buffer 102 is insufficient. Therefore, in the decoding unit 103, the decoding processing unit 201 stops the acquisition of the real-time information packet from the fluctuation absorbing buffer 102 and stops the decoding process. Therefore, the amount of data stored in the fluctuation absorbing buffer 102 is kept constant (the state between the points t4 and t5 shown in FIG. 6B). On the other hand, the silence output unit 202 outputs silence data to the signal selection unit 203. Signal selector 2
Reference numeral 03 selects and outputs silence data from the silence output unit 202.

Further, at the point of time when the fourth packet is received at the point t5, the comparing means 503 stops notifying the comparison result. When the notification of the comparison determination result is stopped, the decoding unit 103 restarts the decoding process.

That is, when the comparison result is not notified, the decoding unit 103
And obtains and decodes the real-time information packet from the device. On the other hand, when the result of the comparison is notified, the acquisition and decoding of the real-time information packet are interrupted and the silent data is output.

In the present embodiment, the presence or absence of the comparison determination result from the comparing means 503 indicates whether or not the data amount in the fluctuation absorbing buffer 102 has decreased on average.
Therefore, the decoding unit 103 stops decoding when the result of the comparison determination is notified, that is, when the amount of data in the fluctuation absorbing buffer 102 is decreasing on average. On the other hand, when the comparison result is not notified, that is, when the data amount in the fluctuation absorbing buffer 102 has not decreased on average, the decoding is performed.

As described above, according to the real-time information receiving apparatus 500 of the present embodiment, the fluctuation absorbing buffer 102
It is detected from the fact that the amount of data stored in the fluctuation absorbing buffer 102 is steadily reduced, because the amount of data stored in the buffer decreases and the time from when the real-time information packet is received until decoding is reduced. Then, by interrupting the decoding of the real-time information packet, the amount of data stored in the fluctuation absorbing buffer 102 is increased, and the time from when the real-time information packet is received to when it is decoded is increased. This makes it possible to recover the delay fluctuation time that can be absorbed by the receiving side.

In this embodiment, the decoding unit 103
After the decoding process is stopped, the decoding process is restarted when a subsequent real-time information packet is received. However, the present invention is not limited to this. The decoding process may be restarted by any method, such as setting the time for stopping the decoding process in advance to a fixed time and restarting after the lapse of the fixed time.

(Embodiment 3) In the real-time information receiving apparatuses 100 and 500 according to Embodiments 1 and 2, silence data is output while the decoding unit 103 stops the decoding process. The real-time information receiving apparatus according to the third embodiment is different in that audio data is output from a sound source unit.

FIG. 7 is a block diagram showing a specific configuration of decoding section 700 of the real-time information receiving apparatus according to the third embodiment. In the decoding unit 700 shown in FIG.
Components having the same reference numerals as in FIG. 2 have the same functions. The other configurations of the real-time information receiving apparatus according to Embodiment 3 are described in real-time information receiving apparatuses 100 and 500 according to Embodiments 1 and 2.
Same as

In decoding section 700 shown in FIG. 7, sound source section 701 outputs audio data reproduced when decoding processing section 201 stops decoding. Signal selector 2
03 depends on the presence or absence of the notification of the continuation (comparison) determination result,
Either the decoded data from the decoding processing unit 201 or the audio data from the sound source unit 701 is selected. If the continuation (comparison) determination result has not been notified, data from the decoding processing unit 201 is selected and output. On the other hand, when the continuation (comparison) determination result is notified, the sound source unit 7
01 is selected and output.

According to the real-time information receiving apparatus according to the third embodiment including decoding section 700 having such a configuration, in real-time information receiving apparatuses 100 and 500 according to the first and second embodiments, decoding section Instead of the silence data that was output when the decoding process was stopped at 103, audio data such as a prepared tone is output from the decoding unit 700. Thereby, the real-time information receiving apparatuses 100 and 500 according to Embodiments 1 and 2
By outputting appropriate audio data such as a tone while decoding is stopped, it is possible to avoid unnaturalness when decoding is stopped.

(Embodiment 4) In the real-time information receiving apparatus according to Embodiment 3, while the decoding section 700 receives the notification of the continuation (comparison) determination result, the decoding processing is continuously stopped. On the other hand, the real-time information receiving apparatus according to Embodiment 4 is different in that the decoding unit intermittently executes the stop of the decoding process when receiving the notification of the continuation (comparison) determination result. .

FIG. 8 is a block diagram showing a specific configuration of decoding section 800 of the real-time information receiving apparatus according to the fourth embodiment. In the decoding unit 800 shown in FIG.
2 and 7 have the same functions. Note that the other configurations of the real-time information receiving apparatus according to Embodiment 4 are the same as those of the real-time information receiving apparatus 100 according to Embodiments 1 and 2.
Same as 500.

In the decoding section 800 shown in FIG. 8, upon receiving the notification of the continuation (comparison) determination result, the decoding notification timer 801 issues a decoding stop instruction for a preset decoding stop instruction period. When the decoding stop instruction period has elapsed, the decoding stop instruction is temporarily stopped. Then, if the continuation (comparison) determination result is notified after the preset decoding stop instruction interval has elapsed, the decoding stop instruction is notified again for the decoding stop instruction time. Further, when the notification of the continuation (comparison) determination result is stopped while the decoding stop instruction is being notified, the notification of the decoding stop instruction is stopped. Note that if the notification of the continuation (comparison) determination result has not been received, the decryption notification timer 801
Does not notify the decoding stop instruction.

The decryption processing unit 802 includes a decryption notification timer 80
When the decoding stop instruction is received from 1, the decoding process is stopped during that time. Thereafter, the decoding processing unit 802 executes the decoding process during the decoding stop instruction interval after the decoding stop instruction period has elapsed. Further, when the decoding stop instruction is received again after the elapse of the decoding instruction interval, the decoding process is stopped again.

The instruction to stop decoding is given in the same manner
Has been notified. Upon receiving the decoding stop instruction from the decoding notification timer 801, the signal selection unit 203 selects and outputs the audio data from the sound source unit 701 during that time. After that, the decoding stop instruction period elapses, and during the decoding stop instruction interval,
Signal selecting section 203 selects and outputs data from decoding processing section 802. Furthermore, when the decoding stop instruction is received again after the elapse of the decoding instruction interval, the sound source unit 701 is again output.
Select and output audio data from.

Next, the operation of the real-time information receiving apparatus according to Embodiment 4 including the decoding section 800 having the above configuration will be described with reference to FIG. FIG. 9 is a block diagram showing a decoding unit 80 of the real-time information receiving apparatus according to the fourth embodiment.
6 is a time chart for explaining the operation of a decryption notification timer 801 at 0. FIG. 9A shows a change in the continuation (comparison) determination result. FIG. 9B shows a change in the decoding stop instruction notified from the decoding notification timer 801.

Upon receiving the notification of the continuation (comparison) determination result at point t1 shown in FIG. 9, the decoding notification timer 801 sets the decoding stop instruction period set in advance (points t1 to t2 shown in FIG. 9).
The decoding processing unit 802 and the signal selection unit 2
Notify 03. At this time, the decoding processing unit 802 stops acquiring and decoding the real-time information packet from the fluctuation absorbing buffer 102. Also, the signal selection unit 2
Reference numeral 03 selects and outputs audio data from the sound source unit 701.

When the decoding stop instruction period has elapsed,
The decoding notification timer 801 stops the decoding stop instruction this time for the decoding stop instruction interval (points t2 to t3 shown in FIG. 9). At this time, the decoding processing unit 802 restarts the acquisition of the real-time information packet from the fluctuation absorbing buffer 102 and the decoding process during the decoding stop instruction interval (points t2 to t3 shown in FIG. 9). Further, the signal selection unit 203 selects and outputs the decoded data from the decoding processing unit 802.

When the continuation (comparison) determination result is further notified when the decoding stop instruction interval has elapsed, the decoding stop instruction is notified again only for the decoding stop instruction period (points t5 to t6 shown in FIG. 9). I do. At this time, the decryption processing unit 80
2 stops the acquisition and decoding of the real-time information packet from the fluctuation absorbing buffer 102 again. Further, the signal selection unit 203 selects and outputs audio data from the sound source unit 701.

In FIG. 9B, the notification of the continuation (comparison) determination result is stopped at the time point t4 when the decoding stop instruction is notified. Therefore, the decryption notification timer 80
1 also stops the notification of the decoding stop instruction. Therefore,
At time point t4, the decoding processing unit 802 restarts the decoding process again.

When the continuation (comparison) determination result is not notified, the decoding notification timer 801 does not notify the decoding stop instruction. Since the decoding stop instruction has not been notified, the decoding processing unit 802 acquires the data from the fluctuation absorbing buffer 102 at the decoding speed, decodes the data, and outputs the decoded data to the signal selection unit 203. The signal selection unit 203
Similarly, since the decoding stop instruction has not been notified, the input from the decoding processing unit 802 is output.

According to the real-time information receiving apparatus according to the fourth embodiment provided with decoding section 800 having such a configuration, in the real-time information receiving apparatuses according to the first to third embodiments, the continuation (comparison) determination result is obtained. Is received, the decoding process is intermittently stopped instead of stopping the decoding process of the decoding unit 103 (700) continuously.
As a result, the effects of the real-time information receiving apparatuses according to the first to third embodiments can be obtained, and even if a large amount of data is reduced, the decoding notification timer 8
01 stops decoding several times in a short time. This makes it possible to reduce the time for stopping the decoding process at one time, and reduce the influence on communication quality due to stopping the decoding process for a long time.

(Fifth Embodiment) In the real-time information receiving apparatus according to the fourth embodiment, audio data is output while the decoding unit 800 stops the decoding process. Real-time information receiving device,
The difference is that interpolation data is output from the interpolation output calculation unit.

FIG. 10 is a block diagram showing a specific configuration of decoding section 1000 of the real-time information receiving apparatus according to the fifth embodiment. In the decoding unit 1000 shown in FIG. 10, the components denoted by the same reference numerals as those in FIGS. 2 and 8 have the same functions. Embodiment 5
Other configurations of the real-time information receiving apparatus according to the first embodiment are the same as those of the real-time information receiving apparatuses 100 and 500 according to the first and second embodiments.

In the decoding unit 1000 shown in FIG.
When receiving the notification of the decoding stop instruction, the interpolation output calculation unit 1001 decodes the data immediately before receiving the previously received decoding stop instruction and the decoding data immediately before receiving the decoding stop instruction. The interpolation data for interpolating both the decoded data obtained by decoding the undecoded data and the decoded data is output to the signal selection unit 203.

The decoding processing unit 1002 has a function provided in the decoding processing unit 802 of FIG. 8 and a function of outputting the decoded data to the interpolation output calculation unit 1001. Further, at the time when the decoding stop instruction is notified, the undecoded data immediately before being subjected to the decoding processing is decoded and the interpolation output calculation unit 10
Output to 01.

The decoding notification timer 1003 has the function of the decoding notification timer 801 shown in FIG. 8, and outputs a decoding stop instruction to the interpolation output calculation unit 10 at the same timing as that for notifying the decoding processing unit 1002 and the signal selection unit 203.
01 is also notified.

Decoding section 1000 having such a configuration
According to the real-time information receiving apparatus according to the fifth embodiment including the above, in the real-time information receiving apparatus according to the fourth embodiment, the audio data output when the decoding unit 800 has stopped the decoding process Instead of the decoded data immediately before the decoding stop instruction is notified and the decoded data obtained by decoding the undecoded data immediately before the decoding processing is performed at the time when the decoding stop instruction is notified. Interpolation data for interpolating both is output from the decoding unit 1000. Thereby, the effects in the real-time information receiving apparatuses 100 and 500 according to the first and second embodiments can be obtained, and the most appropriate interpolation data is output while the decoding is stopped. Therefore, it is possible to reduce the unnaturalness caused by stopping the decoding process.

Further, even if a large amount of data is reduced, the decoding notification timer 1003 operates to stop the decoding a plurality of times in a short time. This makes it possible to reduce the time for stopping the decoding process at one time, and reduce the influence on communication quality due to stopping the decoding process for a long time.

(Embodiment 6) In the real-time information receiving apparatuses according to Embodiments 1 to 3, while the decoding unit receives the notification of the continuation (comparison) determination result, the decoding process is stopped continuously. Further, in the real-time information receiving apparatuses according to the fourth and fifth embodiments, the decoding unit intermittently stops the decoding process when receiving the notification of the continuation (comparison) determination result. The real-time information receiving apparatus according to mode 6 is different in that the decoding unit stops the decoding process only when the real-time information packet is silent data.

FIG. 11 is a block diagram showing a specific configuration of decoding section 1100 of the real-time information receiving apparatus according to the sixth embodiment. In the decoding unit 1100 shown in FIG. 11, the components denoted by the same reference numerals as those in FIG. 2 have the same functions. Note that the other configuration of the real-time information receiving apparatus according to Embodiment 6 is the same as that of the real-time information receiving apparatus 10 according to Embodiments 1 and 2.
Same as 0, 500.

In decoding section 1100 shown in FIG.
Silence output section 1101 outputs audio data corresponding to silence data.

The decoding processing section 1102 has a function provided in the decoding processing section 802 of FIG. 8 and a function of outputting the decoded data to the silence detection section 1103.

The silence detection section 1103 issues a decoding stop instruction only when the continuation (comparison) determination result has been notified and the decoded data obtained from the decoding processing section 1102 is silence data. Signal selector 20
Notify 3. The silence detecting unit 1103 does not notify the decoding stop instruction except in this state.

The signal selecting section 203 receives the audio data from the silence output section 1101 when receiving the notification of the decoding stop instruction, and outputs the decoded data from the decoding processing section 1102 when not receiving the notification of the decoding stop instruction. Select and output.

Decoding section 1100 having such a configuration
According to the real-time information receiving apparatus according to the sixth embodiment including the above, only when the continuation (comparison) determination result is received and the data decoded by the decoding processing unit 1102 is silent data The decoding process of the decoding unit 1100 is stopped. Thus, the effects of the real-time information receiving apparatuses 100 and 500 according to the first and second embodiments can be obtained, and the decoding process stops when the real-time information packet is silent data. Since the decoding process is stopped only when the real-time information packet is silent data, it is possible to avoid a break in audio due to the stop of the decoding process.

(Embodiment 7) In the real-time information receiving apparatus according to Embodiment 6, in addition to the fact that the decoding unit stops the decoding process when the real-time information packet is silent 7 is different from the real-time information receiving apparatus according to 7 in that the decoding unit divides the decoding process and stops.

FIG. 12 is a block diagram showing a specific configuration of decoding section 1200 of the real-time information receiving apparatus according to the seventh embodiment. In the decoding unit 1200 shown in FIG. 12, components having the same reference numerals as those in FIGS. 2 and 11 have the same functions. Other configurations of the real-time information receiving apparatus according to Embodiment 7 are the same as those of real-time information receiving apparatuses 100 and 500 according to Embodiments 1 and 2.

In decoding section 1200 shown in FIG.
The silence detection unit 1201 notifies the decoding notification timer 1202 of silence detection only when the continuation (comparison) determination result is notified and the decoded data acquired from the decoding processing unit 1102 is silence data. Silence detector 1201
Does not notify silence detection except in this state.

[0111] The decoding notification timer 1202 is
When a notification of silence detection is received from 201, a decoding stop instruction is notified for a preset decoding stop instruction time. When the decoding stop time has elapsed, the decoding stop instruction is temporarily stopped. Then, if a notification of silence detection has been received after a preset decoding stop instruction interval has elapsed, a decoding stop instruction is notified again for the decoding stop instruction time. further,
If the notification of the silence detection is stopped while the decoding stop instruction is being notified, the notification of the decoding stop instruction is stopped. If no notification of silence detection has not been received, the decoding notification timer 1202 does not notify the decoding stop instruction.

Decoding section 1200 having such a configuration
According to the real-time information receiving apparatus according to the seventh embodiment including the above, in the real-time information receiving apparatus according to the sixth embodiment, when the real-time information packet is silent data, the decoding unit stops the decoding process. In addition, the decoding unit intermittently stops the decoding process.
Thus, the effects of the real-time information receiving apparatuses according to the first, second, and sixth embodiments can be obtained, and even when the data in fluctuation fluctuation buffer 102 becomes significantly short, decoding is performed by the operation of decoding notification timer 1202. Will be stopped several times in a short time. As a result, it is possible to reduce the time for stopping the decoding process at one time, and it is possible to avoid an increase in a silent section due to stopping the decoding process for a long time.

(Embodiment 8) FIG. 13 is a block diagram showing an I / O system to which a real-time information receiving apparatus 100 according to Embodiment 8 is applied.
FIG. 3 is a block diagram illustrating a configuration of a P telephone device.

[0114] IP telephone apparatus 1300 shown in FIG. 13 includes real-time information receiving apparatus 100 according to the first embodiment. The speaker 1301 receives the audio data converted to an analog signal in the decoding unit 103 of the real-time information receiving apparatus 100, and reproduces the audio data. The microphone 1302 converts the voice input from the user into an analog signal, and converts the analog signal into the encoding unit 1.
Pass it to 303.

The encoding section 1303 converts the analog signal input from the microphone 1302 into a digital audio signal,
The packet is sent to the packet transmission unit 1304. Packet transmission unit 130
Reference numeral 4 divides the digital audio signal input from the encoding unit 1303 into packets of a predetermined fixed length, and transmits the packets at predetermined intervals.

By applying real-time information receiving apparatus 100 according to the first embodiment to IP telephone apparatus 1300, IP telephone apparatus 1300 according to the first embodiment is described.
The effect of the real-time information receiving apparatus 100 according to the first embodiment can be obtained.

In other words, in the present IP telephone apparatus 1300, even if the amount of data stored in the fluctuation absorbing buffer 102 decreases and the time from when the real-time information packet is received until decoding is reduced, the real-time information packet By interrupting the decoding, the amount of data stored in the fluctuation absorption buffer 102 can be increased, and the delay fluctuation time that can be absorbed by the IP telephone device 1300 on the receiving side can be recovered.

It should be noted that IP telephone device 130 of the present embodiment.
0 describes the case where the real-time information receiving apparatus 100 according to Embodiment 1 is applied,
It is not limited to this. The real-time information receiving apparatus applied to IP telephone apparatus 1300 may be real-time information receiving apparatus 500 according to the second embodiment, or its decoding unit may decode the information according to the third to seventh embodiments. A unit may be applied.

By the way, such an IP telephone apparatus 130
0 and the real-time information receiving apparatuses according to the first to seventh embodiments may be connected via a packet network to construct a real-time information transmitting / receiving system. In this case, in the real-time information transmitting / receiving system, the effects of the real-time information receiving apparatuses according to the respective embodiments can be obtained.

[0120]

As described above, according to the present invention,
The amount of data in the fluctuation absorption buffer is detected, and the decoding process of the decoding unit is temporarily interrupted according to the detection result. It is possible to provide a real-time information receiving apparatus capable of recovering the time of delay fluctuation that can be absorbed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a real-time information receiving apparatus according to Embodiment 1 of the present invention.

FIG. 2 is a block diagram showing a specific configuration of a decoding unit of the real-time information receiving apparatus according to the first embodiment.

FIG. 3 is a block diagram showing a specific configuration of a continuous monitoring timer of the real-time information receiving apparatus according to the first embodiment.

FIG. 4 is a time chart for explaining the operation of the real-time information receiving apparatus according to the first embodiment;

FIG. 5 is a block diagram showing a configuration of a real-time information receiving apparatus according to Embodiment 2 of the present invention.

FIG. 6 is a time chart for explaining the operation of the real-time information receiving apparatus according to the second embodiment.

FIG. 7 is a block diagram showing a specific configuration of a decoding unit of the real-time information receiving apparatus according to Embodiment 3 of the present invention.

FIG. 8 is a block diagram showing a specific configuration of a decoding unit of the real-time information receiving apparatus according to Embodiment 4 of the present invention.

FIG. 9 is a time chart for explaining the operation of a decoding notification timer in the decoding unit of the real-time information receiving apparatus according to Embodiment 4.

FIG. 10 is a block diagram showing a specific configuration of a decoding unit of a real-time information receiving device according to Embodiment 5 of the present invention.

FIG. 11 is a block diagram showing a specific configuration of a decoding unit of the real-time information receiving apparatus according to Embodiment 6 of the present invention.

FIG. 12 is a block diagram showing a specific configuration of a decoding unit of the real-time information receiving device according to Embodiment 7 of the present invention.

FIG. 13 is a block diagram showing a configuration when a real-time information receiving apparatus according to Embodiment 8 of the present invention is applied to an IP telephone apparatus.

[Explanation of symbols]

 100, 500 Real-time information receiving apparatus 101 Packet receiving section 102 Fluctuation absorption buffer 103 Decoding section 104 Stored data amount determining means 105 Continuous monitoring timer 201, 802, 1002, 1102 Decoding processing section 202, 1101 Silence output section 203 Signal selection section 301 Notification duration counter 302 Notification duration determination unit 501 Received packet counter 502 Comparison time designation timer 503 Comparison unit 701 Sound source unit 801, 1003, 1202 Decoding notification timer 1001 Interpolation output calculation unit 1103, 1201 Silence detection unit

Claims (12)

[Claims] 1. A packet receiving unit for receiving a real-time information packet transmitted at a fixed interval and a packet length, a fluctuation absorbing buffer for temporarily storing the real-time information packet, and a fluctuation absorbing buffer stored in the fluctuation absorbing buffer. Accumulated data amount determining means for determining a data amount;
A decoding unit for interrupting the decoding of the data stored in the fluctuation absorbing buffer when the time during which the stored data amount determined by the stored data amount determination unit falls below a preset threshold continues for a certain period of time; A real-time information receiving device, comprising: 2. A packet receiving unit for receiving a real-time information packet transmitted at a fixed interval and a packet length, a fluctuation absorbing buffer for temporarily storing the real-time information packet, and a packet receiving unit after communication starts. A reception packet counter that counts the number of reception packets that is the total number of the received real-time information packets;
A decoding unit for interrupting decoding of data accumulated in the fluctuation absorbing buffer when the number of received packets received within a predetermined time from a point in time when reception is started by the packet receiving unit falls below a predetermined threshold value And a real-time information receiving device comprising: 3. The decoding unit according to claim 1, wherein a time when the accumulated data amount falls below a predetermined threshold continues for a predetermined time or a case where the number of received packets received within the predetermined time falls below a predetermined threshold. While the decoding of the data stored in the fluctuation absorbing buffer is interrupted, the decoding processing unit that executes the decoding process of the data stored in the fluctuation absorbing buffer in other cases than the above, and the decoding processing unit A silence output unit that outputs silence data when the decoding process is interrupted, and selects silence data from the silence output unit when the decoding process unit interrupts the decoding process, and executes the decoding process. 3. The real-time information receiving apparatus according to claim 1, further comprising: a signal selecting unit that selects decoded data from the decoding processing unit when the decoding is performed. 4. The decoding unit according to claim 1, wherein a time when the accumulated data amount falls below a predetermined threshold continues for a predetermined time or a case where the number of received packets received within the predetermined time falls below a predetermined threshold. A decoding processing unit that interrupts decoding of data accumulated in the fluctuation absorbing buffer while performing decoding of data accumulated in the fluctuation absorbing buffer in cases other than the above; and A sound source unit that outputs various audio data when the decoding process is interrupted, and when the decoding processing unit performs the decoding process while selecting the audio data from the sound source unit when the decoding process is interrupted. 3. The real-time information receiving apparatus according to claim 1, further comprising: a signal selecting unit that selects decoded data from the decoding processing unit. 5. The decoding unit according to claim 2, wherein a time when the accumulated data amount falls below a preset threshold continues for a predetermined time or a case where the number of received packets received within the predetermined time falls below a preset threshold. A decoding notification timer that repeats outputting a decoding stop instruction for a certain period of time at a certain cycle, and the decoding processing unit performs decoding of the data stored in the fluctuation absorbing buffer when the decoding stop instruction is output. On the other hand, when the decoding stop instruction is not output, the decoding of the data accumulated in the fluctuation absorption buffer is performed, and the signal selection unit performs the decoding when the decoding stop instruction is output. 4. The method according to claim 3, wherein data is selected from a silence output unit or the sound source unit, and the decoded data from the decoding processing unit is selected when the data is not output. The real-time information receiving device according to claim 4. 6. The decoding unit according to claim 1, wherein a time when the accumulated data amount falls below a predetermined threshold continues for a predetermined time or a case where the number of received packets received within the predetermined time falls below a predetermined threshold. A decoding notification timer for repeating the output of the decoding stop instruction for a fixed period of time at a fixed cycle; and a decoding stop instruction for interrupting the decoding of the data accumulated in the fluctuation absorbing buffer when the decoding stop instruction is output. A decoding processing unit that performs decoding of data accumulated in the fluctuation absorbing buffer when is not output, and receives decoded data from the decoding processing unit, while the decoding stop instruction is output. Decodes the decoded data immediately before the decoding stop instruction is output and the undecoded data immediately before decoding at the time the decoding stop instruction is output. And an interpolation output calculation unit that outputs interpolation data between the decoded data and the interpolation data from the interpolation output calculation unit when the decoding stop instruction is output. A signal selection unit for selecting decoded data from the decoding processing unit,
The real-time information receiving device according to claim 1 or 2, further comprising: 7. The decoding unit according to claim 1, wherein a time when the accumulated data amount falls below a predetermined threshold continues for a predetermined time or a case where the number of received packets received within the predetermined time falls below a predetermined threshold. And a silence detecting unit that outputs a decoding stop instruction when a silent part is detected from the input decoded data, and a decoding unit that is stored in the fluctuation absorbing buffer when the decoding stop instruction is output. A decoding processing unit for executing decoding of data stored in the fluctuation absorbing buffer when data is not output while the decoding of data is interrupted, and silence when the decoding processing unit interrupts the decoding process. A silent output section for outputting data,
A signal selection unit that selects data from the silence output unit when the decoding stop instruction is output, and selects data from the decoding processing unit when it is not output. Claim 1 or Claim 2
Real-time information receiving device as described. 8. The decoding unit according to claim 1, wherein a time when the accumulated data amount falls below a predetermined threshold continues for a predetermined time or a case where the number of received packets received within the predetermined time falls below a predetermined threshold. And a silence detection unit that outputs a silence detection signal when a silence portion is detected from the input decoded data, and outputs a decoding stop instruction for a certain period of time when the silence detection signal is output, for a certain period. A decoding notification timer that repeats with, while the decoding of the data stored in the fluctuation absorbing buffer is interrupted when the decoding stop instruction is output, and when the decoding stop instruction is output, the data is stored in the fluctuation absorbing buffer. A decoding processing unit that performs decoding of the decoded data, a silence output unit that outputs silence data when the decoding processing unit interrupts the decoding process, and the decoding stop instruction is output. A signal selection unit that selects data from the silence output unit when the data is output, and selects data from the decoding processing unit when the data is not output. The real-time information receiving device according to claim 2. 9. A real-time information receiving apparatus according to claim 1, and a reproducing unit for reproducing audio data decoded by a decoding unit of the real-time information receiving apparatus. An encoding unit for encoding audio, and a packet transmission unit for dividing data encoded by the encoding unit into packets of a fixed length and transmitting the packets at predetermined intervals set in advance. Communication device. 10. A real-time information receiving apparatus according to claim 1, a packet network having a variable transmission delay, and said packet network having encoded real-time information at fixed intervals and packet lengths. And a real-time information transmitting device for transmitting to the real-time information transmitting system. 11. A step of receiving a real-time information packet transmitted at a fixed interval and a packet length, a step of temporarily storing the real-time information packet in a fluctuation absorbing buffer, and a step of storing data stored in the fluctuation absorbing buffer. Determining the amount; and suspending the decoding of the data stored in the fluctuation absorbing buffer when the determined accumulated data amount falls below a preset threshold for a certain period of time. A method for removing delay fluctuations, characterized in that: 12. A step of receiving a real-time information packet transmitted at a constant interval and a packet length; a step of temporarily storing the real-time information packet in a fluctuation absorbing buffer; Counting the number of received packets, which is the total number of packets, and data stored in the fluctuation absorbing buffer when the number of received packets received within a certain period of time from the start of reception is less than a predetermined threshold value Interrupting the decoding of the delay fluctuation.