WO2003092227A1 - Bit rate control method and device - Google Patents
Bit rate control method and device Download PDFInfo
- Publication number
- WO2003092227A1 WO2003092227A1 PCT/JP2003/005170 JP0305170W WO03092227A1 WO 2003092227 A1 WO2003092227 A1 WO 2003092227A1 JP 0305170 W JP0305170 W JP 0305170W WO 03092227 A1 WO03092227 A1 WO 03092227A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- bit rate
- probability
- transmission
- rates
- currently set
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims abstract description 75
- 230000005540 biological transmission Effects 0.000 claims abstract description 213
- 238000004891 communication Methods 0.000 claims abstract description 34
- 230000008859 change Effects 0.000 claims description 86
- 230000007423 decrease Effects 0.000 claims description 11
- 230000003247 decreasing effect Effects 0.000 claims description 10
- 230000014509 gene expression Effects 0.000 claims description 7
- 230000009467 reduction Effects 0.000 claims description 7
- 230000001174 ascending effect Effects 0.000 claims description 6
- 239000000654 additive Substances 0.000 claims description 2
- 230000000996 additive effect Effects 0.000 claims description 2
- 230000000630 rising effect Effects 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 7
- 238000013459 approach Methods 0.000 description 6
- 230000006866 deterioration Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000000284 extract Substances 0.000 description 4
- 230000015556 catabolic process Effects 0.000 description 3
- 238000006731 degradation reaction Methods 0.000 description 3
- 230000003044 adaptive effect Effects 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 240000007594 Oryza sativa Species 0.000 description 1
- 235000007164 Oryza sativa Nutrition 0.000 description 1
- 229960001484 edetic acid Drugs 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 235000009566 rice Nutrition 0.000 description 1
- 230000007480 spreading Effects 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
- H04L47/24—Traffic characterised by specific attributes, e.g. priority or QoS
- H04L47/2416—Real-time traffic
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
- H04L47/19—Flow control; Congestion control at layers above the network layer
- H04L47/193—Flow control; Congestion control at layers above the network layer at the transport layer, e.g. TCP related
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
- H04L47/25—Flow control; Congestion control with rate being modified by the source upon detecting a change of network conditions
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L47/00—Traffic control in data switching networks
- H04L47/10—Flow control; Congestion control
- H04L47/38—Flow control; Congestion control by adapting coding or compression rate
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/1066—Session management
- H04L65/1101—Session protocols
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/40—Support for services or applications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L65/00—Network arrangements, protocols or services for supporting real-time applications in data packet communication
- H04L65/80—Responding to QoS
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L69/00—Network arrangements, protocols or services independent of the application payload and not provided for in the other groups of this subclass
- H04L69/16—Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
- H04L69/163—In-band adaptation of TCP data exchange; In-band control procedures
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/234—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs
- H04N21/2343—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/234—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs
- H04N21/2343—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements
- H04N21/23439—Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs involving reformatting operations of video signals for distribution or compliance with end-user requests or end-user device requirements for generating different versions
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/23—Processing of content or additional data; Elementary server operations; Server middleware
- H04N21/24—Monitoring of processes or resources, e.g. monitoring of server load, available bandwidth, upstream requests
- H04N21/2402—Monitoring of the downstream path of the transmission network, e.g. bandwidth available
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
- H04N21/20—Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
- H04N21/25—Management operations performed by the server for facilitating the content distribution or administrating data related to end-users or client devices, e.g. end-user or client device authentication, learning user preferences for recommending movies
- H04N21/266—Channel or content management, e.g. generation and management of keys and entitlement messages in a conditional access system, merging a VOD unicast channel into a multicast channel
- H04N21/2662—Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
Definitions
- the present invention relates to a technique for transmitting real-time traffic such as audio data and image data, and more particularly, to a bit rate control method and apparatus.
- the circuit switching method used in conventional public telephone networks occupies a communication line between both terminals regardless of the presence or absence of information to be transmitted, so that voice and images are transmitted in real time.
- call control since call control is performed by monitoring the utilization rate of the entire network in connection between terminals, there is a problem that the load of call control increases as the number of terminals increases.
- the packet switching system does not occupy the circuit, and therefore has higher network utilization efficiency than the circuit switching system.
- TCP / IP Transmission Control Protocol / Internet Protocol
- call control is not performed and autonomous decentralized rates are used so that each terminal can use the network bandwidth fairly. Since the control is performed, the problem of an increase in the load of the call control as described above does not occur.
- the TCP checks for missing packets, and if a packet loss occurs, requests retransmission to improve communication reliability.
- Protocol secures the bandwidth of each terminal at the time of connection. Although the problems of delay and packet loss are solved, the same network efficiency problem as the circuit switching method occurs.
- TCP-friendly control that performs rate control that is fair to TCP.
- rate control that is fair to TCP.
- TCP friendly control There are the following two types of TCP friendly control.
- AIMD Additional Increase / Multiple Decrease
- RAP Rate-based Congestion Control Mechanism for Realtime Stream in the Internet, "INFOCOM '99 (1999.3)
- a constant value is added when increasing the transmission bit rate, and a value smaller than 1 is multiplied when decreasing the transmission bit rate.
- control is performed with the TCP throughput represented by the following equation (1) as the target bit rate.
- R 1 / (RTTx (2xL / 3) + TOxmin (1,3xV (3xL / 8)) xLx (1 + 32xL 2)) (1)
- RTT is the round Bok trip time
- TO is the timeout period
- L Indicates the bucket loss rate.
- the transmission bit rate is a continuous value. It is assumed that Actually, since the transmission bit rate of the audio / video encoder is discrete, these control methods cannot be applied to the audio / video encoder as it is.
- a voice / image data communication device includes a voice / image coding unit 402, a bucket transmitting unit 403, a bucket receiving unit 404, a bit rate control unit 405, a voice / image decoding unit. 406.
- the audio / image encoding unit 402 encodes the input audio / image 401 and outputs the audio / image bit stream to the packet transmission unit 403.
- the bucket transmitting unit 403 uses an IP / UDP / RTR header (refer to Reference 5: "RTP: A Transport Protocol for Real-Time Applications," IETF RFC1889) in the input audio / video bitstream. Add and send to network. Information necessary for communication of audio and video data is added to the RTP header.
- the bucket receiving unit 404 receives a voice / image bucket from the network, extracts a voice / image bitstream from the received bucket, and outputs it to the voice / image decoding unit 406.
- the audio / image decoding unit 406 decodes the audio / image bit stream obtained from the bucket receiving unit, and outputs output audio / image data 407.
- the packet receiving unit 404 is, for example, an R TCP (Real-time Transport
- the bit rate control section 405 performs bit rate control based on AIMD, TFRC, or the like.
- bit rate control based on AIMD according to the packet loss rate obtained from the packet receiving section 404, if there is no packet loss, a value at the current transmission bit rate is added, and the packet is added. If there is a loss, the target bit rate is calculated by multiplying the current transmission bit rate by a certain value.
- the target bit rate is calculated using the round trip time RTT obtained from the bucket receiving unit 404, the packet loss rate, and the equation (1).
- the round trip time and the packet loss rate use values averaged over a certain time in order to increase the measurement accuracy.
- the target bit rate calculated as described above does not always match one of a plurality of discrete bit rates set in the audio / video encoding unit 402.
- the discrete bit rate closest to the calculated target bit rate is selected, and the audio / video coding unit 402 transmits the selected discrete bit rate. Set as bit rate.
- the audio / video decoding unit 406 decodes the audio / video using the bit rate obtained by the bit rate control unit 405.
- Japanese Patent Application Laid-Open No. 5-260900 discloses an example of a bit rate control method using an encoder having discrete bit rates.
- a video encoding unit capable of setting one of a plurality of bit rates (128 kbps, 64 kbps, 10 kbps, etc.) as a transmission bit rate is provided according to the congestion state of the transmission path.
- Bit rate control Specifically, if congestion occurs in the transmission line, the bit rate is set to one step smaller, and if there is no congestion, one step larger. Set a higher bit rate.
- TCP-friendly control based on AIMD and TFRC is based on the assumption that the bit rate takes a continuous value, so that the audio / video communication in which the bit rate of the encoder takes a discrete value. It cannot be applied as it is. Therefore, the bit rate closest to the target value obtained by the bit rate control is selected. However, doing so causes an error between the target value and the actual value, and this error frequently causes the set transmission bit rate to fluctuate, resulting in deterioration of sound quality / image quality.
- Fig. 2 is a time chart showing the bit rate fluctuation when the conventional autonomous decentralized bit rate control method is adopted.
- a target bit rate is calculated based on network information such as a round trip time and a bucket loss rate, and an encoder is assigned to a discrete bit rate closest to the target bit rate. It is assumed that control for setting is performed.
- R (n + 1) when a certain discrete bit rate R (n + 1) is set, the network becomes congested and the target bit rate decreases, and a lower bit rate R (n) is set. Then, it is assumed that the target bit rate increases.
- the bit rate control unit 405 changes the encoding unit 402 from R (n + 1) to the bit rate closest to the current target value. To R (n). If this state continues for a while, then the target bit rate rises, and in order to follow it, the encoding unit 402 is raised again to R (n + 1). If such transmission bit rate fluctuations are repeated, the quality of real-time traffic between terminals transmitting and receiving audio and video is significantly reduced. Also, a method of switching the bit rate of an encoder according to a round trip time and a bucket loss rate in Documents 3 and 4 is disclosed in Japanese Patent Application Laid-Open No. 5-260900. Fairness with control cannot be achieved. Disclosure of the invention
- an object of the present invention is to provide a real-time traffic It is an object of the present invention to provide a bit rate control method and apparatus capable of suppressing quality degradation of real-time communication even when the transmission bit rate of a packet is discretely changed.
- Another object of the present invention is to provide a bit rate control method and apparatus capable of suppressing fluctuation of a transmission bit rate that degrades the quality of real-time communication and realizing fairness with other control methods such as TCP. It is in.
- bit rate control method characterized by determining a transmission bit rate based on a probability when controlling a transmission bit rate during real-time traffic transmission.
- the transmission bit rate of each terminal is set so that the average value of the transmission bit rates of all terminals becomes the desired bit rate.
- the probability value of changing the transmission bit rate it is possible to perform control with little change in the transmission bit rate.
- the bit rate control method is a bit rate control method for transmitting real-time traffic through a network, the method comprising: a) preparing a plurality of predetermined discrete bit rates; b) providing the plurality of discrete bit rates; Determining the probability of selecting one of any adjacent bit rates among the bit rates; c) determining whether to set one of the bit rates based on the determined probability. It is characterized by.
- the step (b) comprises the steps of: b.1) calculating a target bit rate according to a state of the network; and b.2) adjacent to the calculated target bit rate.
- the bit rate is determined.
- the target bit rate when the target bit rate is calculated, a discrete bit rate adjacent to the target bit rate is determined, and which of the bit rates the encoder should be set to is determined by the target bit rate. It is determined stochastically depending on whether it is close to the bit rate. Therefore, the average setting bit rate of all terminals is close to the target bit rate, which can maintain fairness with other control methods such as TCP, and the bit rate of each terminal trying to approach the target bit rate. Frequently changing settings can be avoided.
- the step (b) comprises: b.1) calculating a target bit rate according to a state of the network; b. 2) calculating the target bit rate and a current setting. The probability of selecting one of the bit rates adjacent to the currently set transmission bit rate is changed depending on the magnitude of the difference from the currently set transmission bit rate.
- the transmission bit rate is only one step up or down from the currently set transmission bit rate R (n), and no abrupt transmission bit rate change occurs. This has the effect of suppressing quality degradation of audio and images.
- the step (b) comprises: b.l) determining a change direction of a transmission bit rate according to a state of the network; and 2) determining the plurality of discrete bit rates.
- the current setting is used.
- the probability of changing the bit rate is changed depending on the position of the transmission bit rate in the range in which the bit rate can be set. Specifically, when packet loss is detected, the terminal that has the currently set transmission bit rate has a higher probability of lowering the bit rate, and the terminal that has the lower transmission bit rate has a lower probability. Conversely, if no packet loss is detected, the terminal with a lower transmission bit rate currently set has a higher probability of increasing the bit rate, and the terminal with a higher transmission bit rate has a lower probability.
- the probability is determined depending on an interval between adjacent bit rates. That is, the size of the interval between adjacent bit rates is reflected in the transmission bit rate lowering and raising probability. ⁇ For example, by reducing the bit rate change probability as the distance to the adjacent bit rate increases, the audio / video Quality deterioration can be suppressed.
- FIG. 1 is a block diagram showing a basic configuration of an audio / video data communication device
- FIG. 2 is a diagram schematically showing a transmission bit rate fluctuation by a conventional bit rate control method.
- FIG. 3 is a diagram schematically showing a transmission bit rate variation by the bit rate control method according to the present invention.
- FIG. 4 is a flowchart showing a bit rate control method according to the first embodiment of the present invention.
- FIG. 5 is a flowchart illustrating a bit rate control method according to a second embodiment of the present invention.
- FIG. 6 is a graph showing the relationship between the target bit rate and the probability Pd obtained by the probability calculation formulas (3.1) to (3.4) used for the bit rate reduction determination, and Fig. 7 shows the bit rate.
- FIG. 8 is a graph showing the relationship between the target bit rate and the probability Pu obtained by the probability calculation formulas (4.1) to (4.4) used for the determination of the rise of the voltage, and FIG. 8 shows the bit according to the third embodiment of the present invention. It is a flowchart showing a rate control method
- FIG. 9 is a block diagram illustrating a configuration of a bit rate control unit that implements each of the above embodiments of the present invention.
- FIG. 10 is a block diagram showing a system configuration in the case where bit rate control is performed from the partner terminal side.
- An audio / video communication apparatus employing the bit rate control method according to the present invention has basically the same overall block configuration as that shown in FIG. 1, but differs in the operation of the bit rate control unit 405.
- bit rate control according to the present invention will be described in detail, assuming that the audio / video encoding unit 402 has N types of discrete bit rates R (0) to R (N-1). . However, R (0) ⁇ R (1) ⁇ * ⁇ ' ⁇ R (N-1).
- FIG. 4 is a flowchart showing bit rate control according to the first embodiment of the present invention.
- the target bit rate Rt is calculated by using a conventional TCP friendly control based on AIMD or TFRC (step # 011).
- bit rate judgment based on the probability P (n) is performed.
- the bit rate is determined using a random number.
- a random number (more precisely, a pseudo-random number) Po is generated in the range of 0 ⁇ Po ⁇ 1 (step 103).
- a uniform random number is used as the random number.
- the obtained random number Po is compared with the probability P (n) calculated in step 102, and it is determined whether the transmission bit rate is R (n) or R (n + 1) (step No. 04).
- R (n + 1) Is determined.
- the audio-image encoding unit 402 encodes the input audio / image data with the designated bit rate R, and transmits the encoded data to the network via the packet transmission unit 403.
- the target bit rate Rt when the target bit rate Rt is calculated, a discrete bit rate adjacent to the target bit rate Rt is determined, and any of the bit rates is determined. Whether an encoder is set for a rate is determined stochastically depending on which bit rate the target bit rate Rt is closer to.
- the target bit rate Rt is close to the bit rate R (n)
- the probability of being set to the bit rate R (n) increases.
- the number of terminals corresponding to the probability is set to the bit rate R (n)
- the remaining devices are It can be considered that it is set to the rate R (n + 1). Therefore, the average set bit rate of all terminals is close to the target bit rate, which can maintain fairness with other control methods such as TCP, and that each terminal tries to approach the target bit rate. It is possible to avoid a situation in which the bit rate setting is frequently changed, which has conventionally occurred.
- the probability of changing the bit rate is determined depending on the difference between the current transmission bit rate and the target bit rate. In this case, in order to avoid a large fluctuation of the transmission bit rate, Only the adjacent bit rate can be changed.
- FIG. 5 is a flowchart showing bit rate control according to the second embodiment of the present invention.
- the target bit rate Rt is calculated as in the first embodiment (step 101), and it is determined whether the target bit rate Rt is smaller than the current transmission bit rate R (n) (step 202). ). If it is determined that Rt is smaller,
- step 202 determine whether or not to lower the transmission bit rate (bit rate reduction determination: steps 204 to 207). If not (NO in step 202), Rt and the current transmission bit rate are determined. It is determined whether or not R (n) is equal (step 203).
- R R (n) is set as it is (step 214). If not (NO in step 203), it is determined whether to increase the transmission bit rate (bit rate increase determination: steps 209 to 212).
- a probability Pd (n) is calculated such that the value increases as the difference between Rt and R (n) increases (step 204).
- the following equation (3) is an example of such a calculation equation.
- bit rate change determination based on the probability Pd (n) is performed.
- the bit rate change determination is performed using, for example, a random number.
- a random number (exactly, (Similar random numbers) Po is generated in the range of 0 ⁇ Po ⁇ 1 (Step 205).
- a uniform random number is used as the tongue number.
- the obtained random number Po is compared with the probability Pd (n) calculated in step 204 (step 206).
- the probability Pu (n) is calculated so that the value increases as the difference between Rt and R (n) increases (step 209).
- the following equation (4) is an example of such a calculation equation.
- bit rate change determination based on the probability Pu (n) is executed.
- the bit rate change determination is performed using, for example, a random number.
- a random number (more precisely, a pseudo-random number) Po is generated in the range of 0 ⁇ ⁇ 1 (step 210).
- a uniform random number is used as the random number.
- the obtained random number Po is compared with the probability Pu (n) calculated in step 209 (step 211).
- the R determined in this way is output to the encoding device 402 (step 215).
- the audio / image encoding unit 402 encodes the input audio / image data at the specified bit rate R, and the encoded data is transmitted to the network via the bucket transmitting unit 403.
- Figure 6 is a graph showing the relationship between the target bit rate determined by Equations (3.1) to (3.4) and the probability Pd.
- Equation (3.1) replaces the denominator of equation (3) with the difference between the current transmission bit rate R (n) and the lowest bit rate R (0), and the target bit rate R t is The probability Pd (n) is generated such that the value increases as the distance from the transmission bit rate R (n) increases.
- Equation (3.2) also generates the same probability Pd (n) as equation (3.1), but the target bit rate R t is smaller than the adjacent bit rate R (n _ 1) at the current transmission bit rate R (n). If it is close to, the probability Pd (n) is set to zero. As a result, useless fluctuation of the transmission bit rate can be suppressed.
- Equation (3.3) indicates that if the target bit rate Rt is higher than the adjacent bit rate R (n-1), the value increases as the target bit rate Rt becomes farther from the current transmission bit rate R (n). Generate the probability P d (n) and fix the probability P d (n) to 1 if the adjacent bit rate is less than P (n ⁇ 1).
- Equation (3.4) also generates the same probability Pd (n) as equation (3.3), but the target bit rate R t is smaller than the adjacent bit rate R (n ⁇ 1) at the current transmission bit rate R ( ⁇ ) If it is close to, the probability Pd (n) is set to zero. As a result, useless fluctuation of the transmission bit rate can be suppressed.
- Equations (3.1) to (3.4) the right side may be multiplied by a constant smaller than 1.
- the smaller the value of this constant the more the fluctuation of the transmission bit rate can be suppressed, but the following ability to the target bit rate decreases.
- Figure 7 is a graph showing the relationship between the target bit rate determined by Equations (4,1) to (4.4) and the probability Pu.
- Equation (4.1) is obtained by replacing the denominator of equation (4) with the difference between the current transmission bit rate R (n) and the lowest bit rate R (0).
- the probability Pu (n) is generated such that the value increases as the transmission bit rate R (n) increases.
- Equation (4.3) indicates that the target bit rate Rt is lower than the adjacent bit rate R (n + 1).
- the probability P u (n) is generated such that the value increases as the distance from the current transmission bit rate R (n) increases, and the probability increases when the adjacent bit rate R (n + 1) or higher. Fix Pu (n) to 1.
- Equation (4.4) also generates the same probability Pu (n) as equation (4.3), but the target bit rate R t is greater than the current bit rate R (n + 1) than the adjacent bit rate R (n + 1). If it is close to R (n), the probability Pu (n) is set to zero. As a result, useless fluctuation of the transmission bit rate can be suppressed.
- Equations (4.1) to (4.4) the right side may be multiplied by a constant smaller than 1.
- the smaller the value of this constant the more the fluctuation of the transmission bit rate can be suppressed, but the lower the followability to the target bit rate.
- the target bit rate Rt and the probability Pd (n) / Pu (n) It is also possible to determine the probabilities by searching using a table in which the correspondences are stored as specific numerical values (in any case, such an expression or table is stored in memory as change probability generation information). It is stored in advance.
- the larger the difference between the currently set transmission bit rate R (n) and the calculated target bit rate Rt the larger the transmission bit rate R (n). Is more likely to change. That is, a terminal whose transmission bit rate R (n) set at present is far from the target bit rate R t has a high probability of changing the transmission bit rate, and a terminal close to the target bit rate has a low probability. Therefore, assuming that a large number of terminals are connected to the network and that the target bit rates are approximately the same for those terminals, the average set bit rate of all terminals is close to the target bit rate. For this reason, fairness with other control methods such as TCP can be maintained, and a situation that has conventionally occurred in which each terminal frequently fluctuates the transmission bit rate setting to approach the target bit rate is achieved. Can be avoided.
- each terminal Only one step up or down from the transmission bit rate R (n) is performed, and no abrupt transmission bit rate change occurs. This has the effect of suppressing quality degradation of audio / video.
- the transmission bit rate is changed according to the packet loss.
- TCP friendly control can be realized even if the settable bit rate is discrete.
- FIG. 8 is a flowchart showing bit rate control according to the third embodiment of the present invention.
- the presence / absence of a bucket loss is detected based on the number of received voice / image packet losses and the packet loss rate notified from the partner terminal (step 301), and there is a bucket loss. It is determined whether or not it is (Step 302).
- step 302 If there is packet loss (YES in step 302), it is determined whether to reduce the transmission bit rate (bit rate reduction determination: steps 303 to 306), and if there is no packet loss (step 302). NO), and determine whether or not to increase the transmission bit rate (bit rate increase determination: steps 308 to 311).
- the probability Pd (n) is calculated so that the value increases as the current transmission bit rate increases (step 303).
- the following equation (5) is an example of such a calculation equation.
- bit rate change determination is performed using random numbers.
- a random number (more precisely, a pseudo-random number) Po is generated in the range of 0 ⁇ Po ⁇ 1 (step 304).
- uniform random numbers are used as random numbers.
- the obtained random number Po is compared with the probability Pd (n) calculated in step 303 (step 305).
- the probability Pu (n) is calculated such that the lower the current transmission bit rate R (n), the larger the value (step 308). 308).
- the following equation (6) is an example of such a calculation equation.
- bit rate change determination based on the probability Pu (n)
- the bit rate change determination is performed using a random number.
- a random number (more precisely, a pseudorandom number) Po (0 ⁇ Po ⁇ 1) is generated (step 309).
- uniform random numbers are used as random numbers.
- the obtained random number Po is compared with the probability Pu (n) calculated in step 308 (step 310).
- the R determined in this way is output to the encoder (step 314).
- the audio / video encoding unit 402 encodes the input audio / video data at the designated bit rate R, and transmits the encoded data to the network through the bucket transmitting unit 403. It is sent to the work.
- Equations (5) and (6) may be multiplied by a constant smaller than 1.
- the smaller the value of this constant the more the fluctuation of the transmission bit rate can be suppressed, but the lower the followability to the target bit rate.
- Equation (9) which indicates that the average value of the transmission bit rate decrease value according to the present embodiment is equal to the TCP friendly control based on the AIMD operation, it is possible to reduce the transmission bit rate.
- P d (n) can be obtained.
- the probability Pd (n) of decreasing the bit rate and the probability Pu (n) of increasing the bit rate for each discrete bit rate are stored in a table in advance.
- the probability Pd (n) of decreasing the bit rate and the probability Pu (n) of increasing the bit rate for each discrete bit rate are stored in a table in advance.
- the bit rate when a packet loss is detected and it is necessary to reduce the bit rate, or because no packet loss is detected, the bit rate is reduced. If the bit rate can be raised, the bit rate change probability is determined based on the position of the currently set bit rate R (n) in the bit rate setting range. . Specifically, when a packet loss is detected, the terminal that has a relatively high bit rate R (n) currently set has a higher probability of lowering the bit rate, and the terminal that has a lower bit rate R (n) has a lower probability. Conversely, if no packet loss is detected, the network is operating smoothly, and the terminal with the currently set bit rate R (n) that is relatively low will switch the bit rate. Increase the probability of ascending, and lower it for high terminals.
- the bit rate lowering and increasing probabilities P d (n) and Pu (n) in the second or third embodiment are adjacent bit rates. Reflect the size of the interval between birds. For example, by reducing the bit rate change probability as the difference between the current transmission bit rate and the adjacent bit rate is larger, it is possible to further suppress the deterioration of voice / image quality.
- the N discrete bit rates R (0) to R (N ⁇ 1) of the audio / video encoding unit 402 are represented by R (0) ⁇ R (1) ⁇ * ' ⁇ R ( N-1).
- the bit rate change probability is set in advance according to the difference between the current transmission bit rate and the adjacent bit rate.
- the probability Pd (n) of decreasing the transmission bit rate and the probability Pu (n) of increasing the transmission bit rate for each of the discrete bit rates are stored in advance in a table.
- bit rate decreases and increases Pd (n) / P u (n) is set so that the value decreases as the distance from the adjacent bit rate increases.
- bit rate change probability is inversely proportional to the distance from the adjacent bit rate.
- Cd (n) is determined by equation (3), (3.1) or (3.2) in the second embodiment, or by equation (5) in the third embodiment.
- Cu (n) is determined by equation (4), (4.1) or (4.2) in the second embodiment, or equation (6) in the third embodiment.
- FIG. 9 is a block diagram illustrating a configuration of a bit rate control unit that implements each of the above embodiments of the present invention.
- the bit rate control unit includes a program control processor 601 such as a digital signal processor (DSP) or a central processing unit (CPU), a program memory 602, and a change probability generation information memory storing a probability calculation formula or table. (Not shown) and.
- a bit rate control program corresponding to any of the first to fourth embodiments is stored in the program memory 602 in advance.
- the program control processor 601 reads out and executes the bit rate control program from the program memory 602, and refers to a calculation formula or a table stored in the change probability generation information memory, according to a round trip time or a packet loss rate. To determine the transmission bit rate R and output it to the audio / video encoder 402. (6) Bit rate control system
- the packet receiving unit 404 receives an RTCP bucket, and extracts information (network information) on the round trip time and the bucket loss rate from the packet.
- Information network information
- bit rate control section 405 bit rate control is performed by the above-described process. That is, bit rate control is performed in the own terminal.
- bit rate control is performed in the own terminal.
- FIG. 10 is a block diagram showing a system configuration in a case where bit rate control is performed from a partner.
- the two end powder A and B are connected to the network, it is assumed that the transmit and receive audio and image data with each other (and the blocks having the same functions as those in FIG. 1 is The description is omitted with the same reference number.
- the packet receiving unit 504 of the terminal A when the packet receiving unit 504 of the terminal A receives a voice / image bucket from the partner terminal B via the network, the packet receiving unit 504 obtains the bucket based on the number of losses of the received voice / image bucket. It generates the first network information such as the bit loss rate and outputs it to the bit rate control unit 505.
- the bit rate control 05 determines the first transmission bit rate R based on the first network information as described in the first to fourth embodiments of the present invention, and the first transmission bit rate R representing the first transmission bit rate R is determined.
- the bit rate information is output to the bucket transmitter 503. Further, the bucket receiving section 504 extracts the second bit rate information generated by the terminal B, and outputs the second bit rate information to the audio / video encoding section 402.
- the packet transmitting section 503 generates a transmission bucket from the first bit rate information and the encoded voice / image information, and transmits the packet to the terminal B through the network.
- the header has a 4-bit field called CMR (Codec Mode Request), which is transmitted from the other end to the own terminal.
- CMR Codec Mode Request
- the bit rate to be transmitted can be specified by Codec Mode (number corresponding to the bit rate).
- the audio / image encoding unit 402 encodes the transmitted audio / image information 401 at the first transmission bit rate specified by the first bit rate information, and the encoded audio / image data is The packet is transmitted from the packet transmitting section 503 to the terminal A together with the second bit rate information generated by the bit rate control section 505.
- terminals A and B control the transmission bit rate of each other, there is no need to exchange network information using the RTCP bucket, and the bandwidth consumed by the RTCP bucket is reduced. Can save money.
- the transmission interval of the RTCP packet is about 5 seconds, it is not possible to respond quickly to changes in the network.
- each terminal detects the state of the network from the packets received, Therefore, it is possible to quickly respond to changes in the network, and the effects of the present invention can be further improved.
- bit rate control method can be applied regardless of the update time. For example, if the update time is 10 seconds and the transition probability is designed to be 0.1, even if the update time is changed to 1 second, if the transition probability is adjusted to 1/1 of 0.01, it is almost the same The effect of can be maintained.
- the bit rate when controlling the bit rate according to the state of the network, the bit rate is determined based on the probability, so that the quality of real-time traffic deteriorates. Such a drastic fluctuation of the bit rate can be suppressed, and fairness with TCP can be realized. That is, even if the available bit rates in all terminals of the communication system are decentralized, the bit rate of each terminal is such that the average value of the bit rates of all terminals is the desired bit rate. By determining the probability value for changing the bit rate, it is possible to perform control with little bit rate fluctuation at each terminal, and improve the quality of real-time communication such as voice and image.
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Computer Networks & Wireless Communication (AREA)
- Multimedia (AREA)
- Databases & Information Systems (AREA)
- Business, Economics & Management (AREA)
- General Business, Economics & Management (AREA)
- Computer Security & Cryptography (AREA)
- Communication Control (AREA)
- Data Exchanges In Wide-Area Networks (AREA)
- Compression Or Coding Systems Of Tv Signals (AREA)
Description
Claims
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP03719175A EP1499073A4 (en) | 2002-04-23 | 2003-04-23 | METHOD AND DEVICE FOR ADJUSTING BIT RATE |
US10/497,400 US20050105604A1 (en) | 2002-04-23 | 2003-04-23 | Bit rate contol method and device |
KR20047007857A KR100615119B1 (ko) | 2002-04-23 | 2003-04-23 | 비트 레이트 제어 방법 및 장치 |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2002120066A JP4000895B2 (ja) | 2002-04-23 | 2002-04-23 | リアルタイム通信のためのビットレート制御方法および装置 |
JP2002-120066 | 2002-04-23 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2003092227A1 true WO2003092227A1 (en) | 2003-11-06 |
Family
ID=29267352
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2003/005170 WO2003092227A1 (en) | 2002-04-23 | 2003-04-23 | Bit rate control method and device |
Country Status (6)
Country | Link |
---|---|
US (1) | US20050105604A1 (ja) |
EP (1) | EP1499073A4 (ja) |
JP (1) | JP4000895B2 (ja) |
KR (1) | KR100615119B1 (ja) |
CN (1) | CN100375468C (ja) |
WO (1) | WO2003092227A1 (ja) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7813809B2 (en) | 2004-06-10 | 2010-10-12 | Medtronic, Inc. | Implantable pulse generator for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US8165692B2 (en) | 2004-06-10 | 2012-04-24 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator power management |
US8195304B2 (en) | 2004-06-10 | 2012-06-05 | Medtronic Urinary Solutions, Inc. | Implantable systems and methods for acquisition and processing of electrical signals |
US8706252B2 (en) | 2004-06-10 | 2014-04-22 | Medtronic, Inc. | Systems and methods for clinician control of stimulation system |
US9205255B2 (en) | 2004-06-10 | 2015-12-08 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator systems and methods for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US9308382B2 (en) | 2004-06-10 | 2016-04-12 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator systems and methods for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US9480846B2 (en) | 2006-05-17 | 2016-11-01 | Medtronic Urinary Solutions, Inc. | Systems and methods for patient control of stimulation systems |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US8254358B2 (en) | 2003-03-06 | 2012-08-28 | Ericsson Ab | Communicating a broadcast message to change data rates of mobile stations |
KR100602916B1 (ko) * | 2003-05-23 | 2006-07-19 | 가부시키가이샤 히다치 고쿠사이 덴키 | 화상전송방법 및 화상전송장치 |
US7599394B2 (en) * | 2003-06-16 | 2009-10-06 | Telefonaktiebolaget Lm Ericsson (Publ) | Common rate control method for reverse link channels in CDMA networks |
GB0321093D0 (en) * | 2003-09-09 | 2003-10-08 | Nokia Corp | Multi-rate coding |
US7616660B2 (en) * | 2003-11-21 | 2009-11-10 | Telefonaktiebolaget Lm Ericsson (Publ) | Common rate control method for reverse link channels in CDMA networks |
JP2006126894A (ja) * | 2004-10-26 | 2006-05-18 | Sony Corp | コンテンツ配信方法、プログラムおよび情報処理装置 |
KR100800794B1 (ko) * | 2005-07-01 | 2008-02-04 | 삼성전자주식회사 | 패킷망을 통해 음성 서비스를 지원하는 이동통신시스템에서 음성 서비스의 전송률을 제어하는 방법 및 장치 |
JP4817990B2 (ja) * | 2005-08-17 | 2011-11-16 | キヤノン株式会社 | 撮像装置及びその制御方法及びプログラム及び記憶媒体 |
GB0622830D0 (en) * | 2006-11-15 | 2006-12-27 | Cambridge Silicon Radio Ltd | Transmission rate selection |
US8001260B2 (en) * | 2008-07-28 | 2011-08-16 | Vantrix Corporation | Flow-rate adaptation for a connection of time-varying capacity |
US7844725B2 (en) | 2008-07-28 | 2010-11-30 | Vantrix Corporation | Data streaming through time-varying transport media |
US7975063B2 (en) * | 2009-05-10 | 2011-07-05 | Vantrix Corporation | Informative data streaming server |
JP2011120168A (ja) * | 2009-12-07 | 2011-06-16 | Kyocera Corp | 通信装置 |
US9137551B2 (en) | 2011-08-16 | 2015-09-15 | Vantrix Corporation | Dynamic bit rate adaptation over bandwidth varying connection |
CN102710374B (zh) * | 2012-05-28 | 2015-05-20 | 天津大学 | 无线流媒体传输中的速率控制方法 |
EP3220681B1 (en) * | 2016-03-18 | 2020-07-15 | Nokia Technologies Oy | Adaptive and dynamic qos/qoe enforcement |
CN110192394B (zh) * | 2016-12-21 | 2023-10-20 | 英国电讯有限公司 | 通过网络传送媒体内容的方法和服务器 |
KR20200100387A (ko) * | 2019-02-18 | 2020-08-26 | 삼성전자주식회사 | 실시간 비트레이트 제어 방법 및 이를 위한 전자 장치 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04144438A (ja) * | 1990-10-05 | 1992-05-18 | Ricoh Co Ltd | 多重化データ分離方法 |
JPH05260090A (ja) * | 1992-03-09 | 1993-10-08 | Nippon Telegr & Teleph Corp <Ntt> | 映像転送方式 |
JPH06252870A (ja) * | 1993-02-24 | 1994-09-09 | Nec Corp | データ多重化伝送方式 |
JPH06276172A (ja) * | 1993-03-18 | 1994-09-30 | Fujitsu Ltd | タイムスロット割付け方法 |
JP2003046976A (ja) * | 2001-07-31 | 2003-02-14 | Matsushita Electric Ind Co Ltd | 映像配信装置、映像配信方法及びプログラム |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6112239A (en) * | 1997-06-18 | 2000-08-29 | Intervu, Inc | System and method for server-side optimization of data delivery on a distributed computer network |
US6567420B1 (en) * | 1999-04-15 | 2003-05-20 | Qualcomm, Incorporated | Method and apparatus for high rate channel access control |
DE60239898D1 (de) * | 2001-02-12 | 2011-06-09 | Lg Electronics Inc | Steuerung der Datenübertragungsrate in der Rückwärtsverbindung für jede Mobilstation einzeln |
US7961616B2 (en) * | 2001-06-07 | 2011-06-14 | Qualcomm Incorporated | Method and apparatus for congestion control in a wireless communication system |
US7363353B2 (en) * | 2001-07-06 | 2008-04-22 | Juniper Networks, Inc. | Content service aggregation device for a data center |
-
2002
- 2002-04-23 JP JP2002120066A patent/JP4000895B2/ja not_active Expired - Fee Related
-
2003
- 2003-04-23 KR KR20047007857A patent/KR100615119B1/ko not_active IP Right Cessation
- 2003-04-23 CN CNB038016664A patent/CN100375468C/zh not_active Expired - Fee Related
- 2003-04-23 WO PCT/JP2003/005170 patent/WO2003092227A1/ja active Application Filing
- 2003-04-23 EP EP03719175A patent/EP1499073A4/en not_active Withdrawn
- 2003-04-23 US US10/497,400 patent/US20050105604A1/en not_active Abandoned
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04144438A (ja) * | 1990-10-05 | 1992-05-18 | Ricoh Co Ltd | 多重化データ分離方法 |
JPH05260090A (ja) * | 1992-03-09 | 1993-10-08 | Nippon Telegr & Teleph Corp <Ntt> | 映像転送方式 |
JPH06252870A (ja) * | 1993-02-24 | 1994-09-09 | Nec Corp | データ多重化伝送方式 |
JPH06276172A (ja) * | 1993-03-18 | 1994-09-30 | Fujitsu Ltd | タイムスロット割付け方法 |
JP2003046976A (ja) * | 2001-07-31 | 2003-02-14 | Matsushita Electric Ind Co Ltd | 映像配信装置、映像配信方法及びプログラム |
Non-Patent Citations (5)
Title |
---|
ABREU-SERNANDEZ V. ET AL.: "Adaptive multi-rate speech coder for VoIP transmission", ELECTRONICS LETTERS, vol. 36, no. 23, 9 November 2000 (2000-11-09), pages 1978 - 1980, XP002969582 * |
HANDLEY MARK ET AL.: "TCP friendly rate control (TFRC): protocol specification", 20 July 2001 (2001-07-20), XP002969580, Retrieved from the Internet <URL:draft-ietf-tsvwg-tfrc-03.txt> * |
JEONG WOOK SEO ET AL.: "A study on the application of an AMR speech codec to VoIP", PROC. OF IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH AND SIGNAL, vol. 3, 2001, pages 1373 - 1376, XP002969581 * |
REJAIE REZA ET AL.: "RAP: an end-to-end rate-based congestion control mechanism for realtime streams in the internet", INFOCOM'99, March 1999 (1999-03-01), pages 1337 - 1345, XP002969579 * |
See also references of EP1499073A4 * |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7813809B2 (en) | 2004-06-10 | 2010-10-12 | Medtronic, Inc. | Implantable pulse generator for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US8165692B2 (en) | 2004-06-10 | 2012-04-24 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator power management |
US8195304B2 (en) | 2004-06-10 | 2012-06-05 | Medtronic Urinary Solutions, Inc. | Implantable systems and methods for acquisition and processing of electrical signals |
US8706252B2 (en) | 2004-06-10 | 2014-04-22 | Medtronic, Inc. | Systems and methods for clinician control of stimulation system |
US9205255B2 (en) | 2004-06-10 | 2015-12-08 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator systems and methods for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US9216294B2 (en) | 2004-06-10 | 2015-12-22 | Medtronic Urinary Solutions, Inc. | Systems and methods for clinician control of stimulation systems |
US9308382B2 (en) | 2004-06-10 | 2016-04-12 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator systems and methods for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US9724526B2 (en) | 2004-06-10 | 2017-08-08 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator systems and methods for operating the same |
US10293168B2 (en) | 2004-06-10 | 2019-05-21 | Medtronic Urinary Solutions, Inc. | Systems and methods for clinician control of stimulation systems |
US10434320B2 (en) | 2004-06-10 | 2019-10-08 | Medtronic Urinary Solutions, Inc. | Implantable pulse generator systems and methods for providing functional and/or therapeutic stimulation of muscles and/or nerves and/or central nervous system tissue |
US9480846B2 (en) | 2006-05-17 | 2016-11-01 | Medtronic Urinary Solutions, Inc. | Systems and methods for patient control of stimulation systems |
US10322287B2 (en) | 2006-05-17 | 2019-06-18 | Medtronic Urinary Solutions, Inc. | Systems and methods for patient control of stimulation systems |
Also Published As
Publication number | Publication date |
---|---|
EP1499073A4 (en) | 2009-12-23 |
KR100615119B1 (ko) | 2006-08-22 |
CN100375468C (zh) | 2008-03-12 |
CN1596528A (zh) | 2005-03-16 |
JP4000895B2 (ja) | 2007-10-31 |
JP2003318966A (ja) | 2003-11-07 |
KR20040096495A (ko) | 2004-11-16 |
EP1499073A1 (en) | 2005-01-19 |
US20050105604A1 (en) | 2005-05-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
WO2003092227A1 (en) | Bit rate control method and device | |
US7167451B1 (en) | User controlled audio quality for voice-over-IP telephony systems | |
EP2382726B1 (en) | Method of transmitting data in a communication system | |
US7295549B2 (en) | Source and channel rate adaptation for VoIP | |
WO2017148260A1 (zh) | 语音编码发送方法和装置 | |
CA2698344C (en) | Adaptive rate control in a communications system | |
RU2305908C2 (ru) | Адаптивный способ оценивания скорости передачи мультимедийных данных | |
US6757277B1 (en) | System and method for coding algorithm policy adjustment in telephony-over-LAN networks | |
US8588071B2 (en) | Device and method for adaptation of target rate of video signals | |
JP2001160824A (ja) | 有線無線混在網データ配信装置及びデータ配信方法 | |
US8340126B2 (en) | Method and apparatus for congestion control | |
JP2008042850A (ja) | 中継装置、中継方法および中継プログラム | |
JP4748729B2 (ja) | データおよび対応するプロダクトを送信する準備のための装置と方法 | |
RU2004118718A (ru) | Способ обеспечения услуги потоковой передачи видеоданных | |
WO2007061087A1 (ja) | 通信装置、通信システム、通信方法、および、通信プログラム | |
JP2004072720A (ja) | メディア伝送方法並びにその送信装置及び受信装置 | |
CN112367490B (zh) | 面向交互视频传输质量提升的混合学习方法、装置及设备 | |
WO2023155747A1 (zh) | 数据编码码率自适应调节方法、装置、设备和存储介质 | |
JP3541288B2 (ja) | パケット交換システム及び通信端末 | |
JP2007036960A (ja) | 動的にセッションを切り替えるrtp通信用端末、呼接続システム及びプログラム | |
WO2006135250A2 (en) | Method for down-speeding in an ip communication network | |
KR100636278B1 (ko) | 브이오아이피 단말의 음성 큐오에스 보장 시스템 및 그 방법 | |
JP4973453B2 (ja) | 送信端末、通信システム、プログラム、及びデータ品質制御方法 | |
JP2003244232A (ja) | Ipパケット通信システム、及びそのゲートウェイ装置、マネジメント装置、並びにパケットサイズ制御方法 | |
JP2005175694A (ja) | 音声通信装置、及び、音声通信方法 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): CN KR US |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): DE FI FR GB SE |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 1020047007857 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2003719175 Country of ref document: EP Ref document number: 20038016664 Country of ref document: CN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 10497400 Country of ref document: US |
|
WWP | Wipo information: published in national office |
Ref document number: 2003719175 Country of ref document: EP |