JP2015050591A - Information processor, information processing method, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information processor, an information processing method, and a program which can suppress delay and abandonment of a video frame with high priority by reducing internal collision of a transmission frame with high priority and improve video quality.SOLUTION: An information processor includes: reception means which receives a packet that includes at least a part of a frame of video data; determination means which determines a frame type corresponding to at least a part of the frame included in the received packet; setting means which sets a plurality of priorities in order of the frame type having a large contribution to a video quality with respect to the packet whose frame type is determined; storage means which stores the packet whose priority is set to a queue associated with the priority; detection means which detects a communication situation of the packet stored to the queue; and control means which controls transmission of the packet stored to the queue on the basis of the detected communication situation and the set priority of the packet.

Description

  The present invention relates to an information processing apparatus, an information processing method, and a program.

  In recent years, wireless local area network (LAN) technology has become widespread and has been used in various places such as homes, offices, railway stations, restaurants and hotels. Wireless LAN technologies such as IEEE802.11 series of IEEE (American Institute of Electrical and Electronics Engineers), that is, IEEE802.11a, b, exist in the wireless LAN.

  A standard that provides a QoS (Quality of Service) function in the IEEE 802.11 wireless LAN is IEEE 802.11e. In IEEE 802.11e, EDCA (Enhanced Distributed Channel Access) is defined as a priority control method.

  FIG. 14 is a diagram showing an outline of priority control in EDCA. In EDCA, packets from higher layers are classified into four access categories (AC: Access Category), stored in each queue, and a radio frame is transmitted according to each priority. The four access categories (hereinafter referred to as AC) are voice AC (AC_VO), video AC (AC_VI), best effort AC (AC_BE), and background AC (AC_BK) in descending order of priority. As a packet classification method, generally, a value of a ToS (Type of Service) field of an IP header or a VLAN-Tag priority value defined by IEEE 802.1Q is assigned to four ACs for classification. EDCA parameters used for radio frame transmission are determined for each of the four classified ACs, and the difference in priority of transmission opportunities is determined by these parameters.

  In DCF (Distributed Coordination Function), which is a normal IEEE 802.11 wireless LAN access method, a radio frame is transmitted by a procedure called CSMA / CA (Carrier Sense Multiple Access Avidance Aviation). In CSMA / CA, a terminal holding a frame to be transmitted first performs an operation called carrier sense to check whether a frequency band to be used is in use. If it is not in use, it is basically waiting for transmission by a predetermined waiting time called DIFS (Distributed Inter Frame Space) and the number of slots called a contention window (CW: Contention Window). If the use of radio waves is not detected by the sense, transmission is started.

  In EDCA, this CSMA / CA procedure is performed independently for each AC, and an AC or wireless LAN terminal whose standby time is first zero obtains the right to transmit a radio frame. When the waiting times of a plurality of ACs simultaneously become 0, a high priority AC acquires a transmission right according to a predetermined priority. The number of slots in the contention window (hereinafter also referred to as “CW”) to be waited for is randomly selected for each frame for transmitting an integer value equal to or smaller than the contention window size set in each AC, and the number of slots is determined. This avoids frame collisions between ACs and terminals that attempt to transmit simultaneously.

  The contention window size is defined by two parameters, CWmin and CWmax. When the frame is transmitted for the first time, CWmin is used as the contention window size. When retransmitted due to an error or the like, the contention window size is increased from CWmin, and the number of waiting slots is selected from a wider range of values. The more errors there are, the more likely it is in a congested state and many collisions, so collisions can be avoided by increasing the randomness. The contention window size increases with each retransmission, but the upper limit is defined by CWmax.

  In EDCA, a parameter called AIFS (Arbitration Inter Frame Space) is set instead of DIFS, and the waiting time for each AC is set to be smaller as the AC has a higher priority. Similarly, CWmin and CWmax are also set smaller as the priority is higher, and the probability that a packet with a higher priority AC can be preferentially transmitted is higher. Further, in EDCA, an AC that has once acquired a transmission right enables continuous transmission of radio frames at a minimum waiting time SIFS (Short Inter Frame Space) interval. This continuous transmission time is called TXOP (Transmission Opportunity), and this upper limit time is defined for each AC as TXOP limit. When TXOPlimit = 0, transmission of only one packet is permitted.

  EDCA realizes priority control using such parameters. Access parameters (AIFS, CWmin / CWmax, TXOPlimit) used in the four ACs of EDCA have standard values in each terminal, but each terminal is described by describing it in a beacon frame transmitted from the base station. Can notify the parameters to be used. When the terminal receives the beacon frame, the terminal updates the EDCA parameter to be used, and subsequent transmissions are performed using the updated parameter. Therefore, the base station can control the access parameters of the surrounding EDCA compatible terminals.

  On the other hand, compression coding is an indispensable technique for transmitting moving images via a communication line. MPEG (Moving Picture Experts Group) and MPEG-2 standards (MPEG-1 and MPEG-2 standards (MPEG-1), standardized by ISO (International Organization for Standardization) / IEC (International Electrotechnical Commission) 4) and H.264 standardized by ITU-T (International Telecommunication Union-Telecommunication Standardization Sector). H.26x series standards (H.261, H.262 and H.263), or H.264, which is a video compression coding standard standardized jointly by both standards organizations. H.264 / AVC standards (the official recommendation names in both organizations are MPEG-4 Part 10: Advanced Video Coding and H.264, respectively).

  In such various moving image compression encoding, for example, in the MPEG standard, a group of pictures (GOP: Group of Pictures) unit composed of a combination of several frames of video signals as a unit of compression, reproduction and editing is configured. Is done. FIG. 15 is a diagram illustrating a frame configuration of video data. As shown in FIG. 15, a group of pictures (hereinafter referred to as GOP) is composed of different video frames including various information. For example, in the MPEG standard, an image frame for intra-frame encoding is an I (Intra) frame, an image frame for forward inter-frame predictive encoding with a past frame as a reference image is a P (Predictive) frame, and past and future An image frame that performs bidirectional inter-frame predictive coding using the above frame as a reference image is referred to as a B (Bidirectionally) frame. Each frame is composed of a plurality of packets as shown in FIG.

  On the other hand, H. In H.264 / AVC, a frame that can be used as a reference image may be a past two frames as a reference image or a future two frames as a reference image regardless of the time. Further, three or more frames can be used as the reference image regardless of the number of frames that can be used as the reference image. Therefore, in MPEG-1 / 2/4, the B frame refers to a bi-directional prediction frame. In H.264 / AVC, the B frame is a bi-predictive frame because the time of the reference image does not matter.

  Here, from the viewpoint that the degree of contribution to the overall video quality is large, the importance of each video frame is important in the order of I frame> P frame> B frame. That is, the delay or discard of the B frame has a smaller influence on the video quality than the delay or discard of the I or P frame.

  Japanese Patent Laid-Open No. 2004-228688 discloses a method of collecting transmission frames and prioritizing channel access for each MPEG frame having a different priority by identifying the frame type in order to further differentiate the priority of transmission frames within a single AC. A wireless system for attaching is disclosed. The wireless system described in Patent Document 1 reduces the delay and jitter of a high-priority video frame by controlling the CW and TXOP values of the video frame for each priority in a single AC transmission frame. The video quality is improved.

  However, the conventional IEEE 802.11e EDCA standard classifies traffic into four ACs, stores them in each queue, and provides different QoS depending on the priority of the AC. Each priority is not considered. That is, since the I frame, the P frame, and the B frame are handled in the same manner, the occurrence rate of delay or discard of each video frame is the same, and thus there is a problem that the video quality cannot be improved.

  Further, in the wireless system described in Patent Document 1, since the CW and TXOP values of video frames are controlled for each priority, the waiting time of different queues in the wireless system becomes 0 at the same time, and a plurality of data is output from the queue. This increases the possibility of internal collisions. For this reason, there is a problem that throughput is deteriorated because internal collision processing is frequently performed. In addition, when the wireless environment is deteriorated, there is a problem that the discard of the video frame cannot be controlled based on the importance of each video frame type.

  The present invention has been made in view of the above, and it is possible to improve video quality by suppressing delay and discard of high-priority video frames by reducing internal collision of high-priority transmission frames. It is an object to provide an information processing apparatus, an information processing method, and a program.

  In order to solve the above-described problems and achieve the object, an information processing apparatus according to the present invention includes a reception unit that receives a packet including at least a part of a frame of video data and the packet received by the reception unit. Determining means for determining a frame type corresponding to at least a part of the frame, and a plurality of priorities with respect to the packet for which the frame type is determined in order of the frame type in which the frame type has a large contribution to the video quality. Setting means for setting, storage means for storing the packets according to the priority set by the setting means in a plurality of queues associated with a plurality of priorities that can be set by the setting means, and the queue Detecting means for detecting the communication status of the packet stored in the network, and the detected communication status and the priority of the set packet It characterized in that it comprises a control means for controlling the delivery of the packets stored in the plurality of queues based on.

  According to the present invention, there is an advantageous effect that video quality can be improved by suppressing delay and discard of a video frame with high priority by reducing internal collision of transmission frames with high priority.

FIG. 1 is a diagram illustrating a hardware configuration example of the information processing apparatus according to the present embodiment. FIG. 2 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. FIG. 3 is a diagram for explaining a configuration of a packet input to the radio unit of the information processing apparatus according to the present embodiment. FIG. 4 is a diagram illustrating information related to the type and priority of a video frame. FIG. 5 is a diagram for explaining the CSMA / CA procedure. FIG. 6 is a diagram showing the relationship between the transmission rate and the lowest S / N ratio. FIG. 7 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. FIG. 8 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. FIG. 9 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. FIG. 10 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. FIG. 11 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. FIG. 12 is a diagram illustrating an example of a functional configuration of a wireless unit of the information processing apparatus according to the present embodiment. FIG. 13 is a flowchart illustrating an example of a control operation of the information processing apparatus according to the present embodiment. FIG. 14 is a diagram showing an outline of priority control in EDCA. FIG. 15 is a diagram illustrating a frame configuration of video data.

  Hereinafter, an embodiment of an information processing apparatus, an information processing method, and a program according to the present invention will be described in detail with reference to the accompanying drawings.

  In this embodiment, compression encoding according to the MPEG series standard is used and a frame is taken as an example of the encoding unit. However, the encoding unit may be a field.

  The information processing apparatus according to the present embodiment analyzes the service type field of the input packet and determines the frame type of the video data. The information processing apparatus redefines a ToS (Type of Service) field in the packet header as a DS (DiffServ) field for a packet including at least a part of a frame of video data, and the frame type is determined for the video quality. A plurality of priorities are set in order of the frame type having the largest contribution. Then, the information processing apparatus stores packets in a plurality of queues associated with the plurality of priorities according to the set priorities. The information processing apparatus determines the packet storage status of a plurality of queues that store packets, and detects the communication status of the packets stored in the plurality of queues. The information processing apparatus controls transmission of packets stored in a plurality of queues based on the detected communication status and the set priority of the packet. Accordingly, the information processing apparatus sets a high priority to a packet including a frame having a large contribution to the video quality, stores the packet in a plurality of queues for each priority order, and stores the video data having a high priority. The packet including this frame can be transmitted with the highest priority. Therefore, the information processing apparatus can reduce internal collision of high-priority transmission frames, suppress delay and discard of high-priority video frames, and improve video quality.

  In the following, an example applied to a personal computer will be described as an example of the information processing apparatus of the present embodiment, but the present invention is not limited to this, and the type of information processing apparatus to which the present invention is applied is arbitrary. For example, it may be a portable information terminal (for example, a smartphone, a tablet, etc.), a projector device, a device dedicated to video conferencing, or the like.

  FIG. 1 is a diagram illustrating a hardware configuration example of the information processing apparatus according to the present embodiment. As illustrated in FIG. 1, the information processing apparatus 10 according to the present embodiment includes a CPU 11, an application processing unit 12, a memory 13, a wireless unit 14, an antenna 15, and a bus line 16.

  A CPU (Central Processing Unit) 11 controls the overall operation of the information processing apparatus 10. For example, the CPU 11 reads an application from the application processing unit 12 and executes the memory 13 as a working memory.

  The memory 13 is a storage medium and stores a program for the information processing apparatus 10. The memory 13 is used as a work area for the CPU 11. That is, the memory 13 has a function of ROM (Read Only Memory) and RAM (Random Access Memory).

  The application processing unit 12 can execute various applications such as video / audio / web browsing. The application processing unit 12 inserts data such as a video frame into a real-time transport protocol (RTP) packet, and transfers the RTP packet with the video frame inserted to the wireless unit 14.

  The wireless unit 14 is a communication unit that performs conversion between a data signal and a wireless signal in accordance with a prescribed protocol, and performs wireless communication with other communication devices by inputting and outputting wireless signals via the antenna 15. For example, the wireless unit 14 wirelessly transmits packet data such as video data to another communication device according to an instruction from the CPU 11.

  The bus line 16 electrically connects the above-described components as shown in FIG. The bus line 16 is, for example, an address bus or a data bus.

  Although not shown, the information processing apparatus 10 includes an input unit, a display unit, a storage device, a recording medium, and the like. The input unit is a user interface that receives various user operation instructions, such as a keyboard and a mouse. For example, a touch panel or a voice input device can be used as the input unit. The display unit is, for example, a display that displays an image or the like. The display is, for example, an FPD (Flat Panel Display) such as a liquid crystal or an organic EL. The storage device is, for example, a nonvolatile memory such as an HDD (Hard Disk Drive) or a flash memory. The storage medium is detachable from the information processing apparatus 10.

  The storage medium may be a USB memory, a flash memory, an EEPROM (Electrically Erasable and Programmable ROM), or the like as long as it is a non-volatile memory that reads or writes data under the control of the CPU 11.

  The application may be distributed in a state recorded in a storage medium or downloaded from a server (not shown in FIG. 1).

  Further, the program for the information processing apparatus 10 may be a file in an installable format or an executable format, and may be recorded and distributed on a computer-readable recording medium such as the storage medium.

  FIG. 2 is a diagram illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. As shown in FIG. 2, the wireless unit 14 of the information processing apparatus 10 according to the present embodiment includes an input control unit 21, a queue buffer unit 22, a communication unit 23, a video output control unit 24, and a video queue size. And a change unit 25.

  The input control unit 21 includes a receiving unit 101, a determining unit 102, and a setting unit 103. For example, the accepting unit 101 accepts a packet including at least a part of a frame of video data. The discriminating unit 102 discriminates a frame type corresponding to at least a part of the frame included in the packet received by the receiving unit 101. The setting unit 103 sets a plurality of priorities for the packets whose frame types are determined by the determination unit 102 in order of the frame types in which the frame types have a large contribution to the video quality. That is, when the input packet is classified into the video category (AC_VI), the priority is redefined for the input packet for each video frame type. Details of the method for redefining the priority will be described later. The input control unit 21 selects a queue corresponding to the priority of the packet whose priority is redefined, and transfers the packet to the selected queue.

  Note that the video data is, for example, moving image data, and the frame type is, for example, any one of an I frame, a P frame, and a B frame defined in the MPEG standard, and a frame type that has a large contribution to the video quality. The order is important in the order of I frame> P frame> B frame from the importance of each video frame.

  Here, details of a method for redefining the priority of a packet including at least a part of a frame of video data will be described. FIG. 3 is a diagram for explaining a configuration of a packet input to the radio unit of the information processing apparatus according to the present embodiment. As shown in FIG. 3, an IP packet generally has a QoS-designated dedicated field called ToS (Type of Service) 31 in the IP header. Hereinafter, ToS is also referred to as a service type field.

  The service type field 31 is used for designating ToS indicating the priority of the IP packet. For example, when a specific value is designated, a setting can be made such that routing processing is performed in preference to other packets. The service type field 31 is an 8-bit field in the 9th to 16th bits of the IP header. The information processing apparatus 10 refers to this field and transfers the packet so as to realize the requested quality. The first 3 bits of the service type field 31 are called IP Precedence, and can specify eight levels of transfer priority. As for the value of this IP Precedence, for example, an IP packet transmitted from a PC is generally transmitted with a value of [0]. The higher the IP Precedence value, the higher the priority. The latter five bits are generally all [0] values, but by changing the bit pattern, it is possible to specify such as maximizing security, giving priority to throughput, and suppressing monetary costs. Further, the service type field 31 can be redefined by the setting unit 103 of the input control unit 21. That is, in the present embodiment, the priority is set by redefining the 6 bits from the top of the 8 bits as the DiffServ field. An identifier called DSCP (DiffServ Code Point) is stored in the DiffServ field, and the traffic flow type is displayed. In the present embodiment, the information processing apparatus 10 can perform priority control with reference to the identifier DSCP in the DiffServ field.

  The determining unit 102 of the input control unit 21 of the information processing apparatus 10 analyzes the service type field 31 of the packet including at least a part of the frame of the video data received by the receiving unit 101. The discriminating means 102 extracts a packet classified into the video category (AC_VI), analyzes the data body of the packet, and discriminates the frame type of the video frame. Then, as described above, the setting unit 103 of the input control unit 21 of the information processing apparatus 10 redefines the ToS field in the IP header of the IP packet as a DS (DiffServ) field and prioritizes each frame type of the video frame. Set information related to degrees. The setting means 103 sets one priority from a plurality of priorities in the order of the frame type in which the frame type has a large contribution to the video quality for the packet including at least a part of the frame of the video data.

  FIG. 4 is a diagram illustrating information related to the type and priority of a video frame. As information related to the type and priority of the video frame set in the DS (DiffServ) field, as shown in FIG. 4, the first 3 bits of 6 bits are values indicating the video category (AC_VI) frame. It is. That is, the first 3 bits indicate a packet including at least a part of a frame of video data. For example, if the packet is classified into the video category (AC_VI), the setting unit 103 sets a value of “001” in the first three bits as shown in FIG. The value set in the first 3 bits is not limited to “001” and can be set arbitrarily.

  The remaining 3 bits are values indicating the video frame type. For example, in the case of an I frame, the setting unit 103 sets a value of “001” to the remaining 3 bits as shown in FIG. For example, in the case of a P frame, the setting unit 103 sets a value “010” to the remaining three bits as shown in FIG. For example, in the case of a B frame, the setting unit 103 sets a value of “011” to the remaining 3 bits as shown in FIG. In this way, the setting unit 103 sets information related to the priority for each video frame type using the redefined DS (DiffServ) field. In the above example, the priority order of the frame types is “001 (I frame)”> “010 (P frame)”> “011 (B frame)”. Note that the frame type and the values set in the remaining three bits are not limited to this, and can be arbitrarily set.

  Returning to FIG. 2, the queue buffer unit 22 includes storage means 104. The storage unit 104 stores a packet in which a priority is set for each frame type in a plurality of queues associated with a plurality of priorities that can be set by the setting unit 103. That is, the storage unit 104 stores a packet including at least a part of a frame of video data whose priority is redefined by the setting unit 103 in a queue corresponding to the priority for each frame type. In the present embodiment, packets classified into the video category (AC_VI) include, for example, a queue 111 for storing packets including I frames and P frames for each frame type as shown in FIG. The packet is sorted and stored in a queue 112 for storing packets and a queue 113 for storing packets including B frames. Thereby, in the information processing apparatus 10, for example, a packet including an I frame having a large contribution to the video quality and a packet including a B frame having a small contribution to the video quality are associated in order of priority. Since it is stored in the queue, it can be differentiated by giving priority to each frame type.

  The queue buffer unit 22 is further classified into a queue that stores packets classified into the voice category (AC_VO), a queue that stores packets classified into the best effort category (AC_BE), and a background category (AC_BK). And a queue for storing packets to be processed.

  The queue buffer unit 22 accepts the size change from the changing unit 109 of the video queue size changing unit 25, and changes the size of the queue 111 to the queue 113 that stores packets classified into the video category (AC_VI). Is possible. In other words, changing the queue size means increasing or decreasing the number of queue buffer stages for storing packets.

  The communication unit 23 includes a detection unit 105. The communication unit 23 transmits each packet stored in each queue of each category of the queue buffer unit using, for example, the CSMA / CA method including internal collision processing. The detecting means 105 detects the communication status of the packets stored in each queue. Here, each queue is classified into a queue storing packets classified into the video category (AC_VI), a queue storing packets classified into the audio category (AC_VO), and a best effort category (AC_BE). A queue for storing packets and a queue for storing packets classified into the background category (AC_BK).

  The detecting means 105 uses the S / N ratio mea which is the signal-to-noise ratio of the packet stored in each queue as a wireless connection parameter based on the communication status of the packet, and the PPS (Packet Per) which is the number of packets which can be processed per second. Second) is detected. Here, the S / N ratio is obtained by subtracting the noise intensity from the received signal intensity. In a state where the emission of radio waves from the antenna 15 is stopped, it can be determined that the radio waves are not emitted from other terminals. Therefore, the detection means 105 detects the intensity of noise during this no radio wave state. A packet indicates a group of data distributed on the network, and the amount of data per packet varies depending on the standard. To convert to communication speed, it is necessary to multiply the capacity per packet.

  Here, the detection method of the noise intensity in the detection means 105 of the communication unit 23 will be described by taking CSMA / CA as an example. FIG. 5 is a diagram for explaining the CSMA / CA procedure. For example, a wireless LAN terminal (information processing apparatus) A performs an operation called carrier sense and checks whether or not a frequency band to be used is in use. If the frequency band is not in use, as shown in FIG. 5, if no radio wave is detected in a waiting time called DIFS (Distributed Inter Frame Space) 121, it is determined that “a signal does not flow on the radio wave”. After that, after waiting for a random time (backoff) 122, data transmission 123 is performed. A reception completion notification (Ack: Acknowledgment) 125 transmitted from an AP (Access Point) to a terminal is transmitted after waiting for a time called a SIFS (Short Inter Frame Space) 124. Next, if no radio wave is detected in DIFS 126, wireless LAN terminal (information processing apparatus) B waits for backoff 127 before transmitting data 128.

  Therefore, when using CSMA / CA as described above, the SIFS state (the state in which the emission of radio waves from the antenna is stopped) is a non-radio wave state in which radio waves are not emitted from other terminals. Detect the noise intensity. Then, the detection unit 105 calculates the S / N ratio mea from the detected noise intensity. As a method for calculating the S / N ratio mea, a general method can be arbitrarily used.

  Further, the detecting means 105 uses the preset allowable maximum S / N ratio max and allowable minimum S / N ratio min, and the S / N ratio mea calculated by detecting the noise intensity to perform wireless communication. The situation parameter Qwireless is calculated from the following equation (1).

  In a normal wireless communication situation, since the S / N ratio min <S / N ratio mea <S / N ratio max, the value of Qwireless is 1 or more. The larger the Qwireless value, the better. On the other hand, when the radio environment is very good (S / N ratio mea ≧ S / N ratio max), the value of Qwireless is 1 or less. Further, when the wireless environment is very bad (S / N ratio mea <S / N ratio min), there is a high possibility that wireless connection cannot be established.

  Here, the allowable maximum S / N ratio max and the allowable minimum S / N ratio min will be described. FIG. 6 is a diagram showing the relationship between the transmission rate and the lowest S / N ratio. For example, in IEEE802.11a, as shown in FIG. 6, the minimum S / N ratio at a transmission rate of 54 Mbps is 26 dB, and the minimum S / N ratio at a transmission rate of 6 Mbps is 9 dB. That is, if the lowest S / N ratio is 9 dB or less, there is a high possibility that wireless connection cannot be established. Therefore, the allowable maximum S / N ratio max can be set from the minimum S / N ratio at the transmission rate by detecting the transmission rate. Further, the allowable minimum S / N ratio min can be set to 9 dB in IEEE 802.11a, for example. The allowable maximum S / N ratio max and the allowable minimum S / N ratio min are not limited to this, and can be arbitrarily set depending on the wireless LAN to be used.

  Next, a method for calculating the PPS by the detection unit 105 will be described. For example, the time required to transmit one frame is, for example, 8 bytes (preample, SFD) +64 bytes (Ethernet frame) +12 bytes (IFG), a total time of transferring 84 bytes = 672 bits. is necessary. Therefore, the detecting means 105 can calculate the PPS from the following equation (2) after detecting the transmission rate.

  PPS = Transmission rate (bps: bit per second) ÷ 672 (bit / packet) (2)

  Thus, the PPS value can be calculated using the above formula (2), for example, when the transmission rate is 10 Mbps, 10000000 ÷ 672≈14880.

  The detection unit 105 delivers the wireless communication status parameter Qwireless and PPS value obtained as described above to the video output control unit 24.

  Returning to FIG. 2, the video output control unit 24 includes a control unit 106 and a monitoring unit 107. The control unit 106 includes a plurality of correspondences associated with a plurality of priorities based on the communication status detected by the detection unit 105 of the communication unit 23 and the priority of the packet set by the setting unit 103 of the input control unit 21. Controls the sending of packets stored in the queue. Here, the communication status refers to noise intensity and transmission rate. The plurality of queues associated with the plurality of priorities are specifically queues that store packets classified into the video category (AC_VI). For example, as shown in FIG. 2, a plurality of queues associated with a plurality of priorities include a queue 111 that stores packets including I frames and a queue 112 that stores packets including P frames for each frame type. And a queue 113 for storing packets including B frames.

  Here, a method for controlling packet transmission by the control means 106 will be described. 7 and 8 are diagrams illustrating an example of a functional configuration of the wireless unit of the information processing apparatus according to the present embodiment. 7 and 8 have the same configuration as that in FIG. 2, and thus the same reference numerals are given and detailed description thereof is omitted. 7 and 8, for example, the detected PPS is X packets / second, and each queue has a queue I (queue 111) for storing the highest priority packet, and the next highest priority after the highest priority. An example will be described in which the queue P (queue 112) for storing the packets of C and the queue B (queue 113) for storing the packets with the lowest priority are described. Further, a case where the newly input packet 114 is the highest priority packet including the I frame will be described as an example.

  As shown in FIG. 7, the control unit 106 sets a preset threshold value as shown in FIG. 7 so that the number of packets stored in the queue I (queue 111) storing the highest priority packets including the I frame is monitored. If not exceeding, the ratio of PPS, which is the number of packets transmitted from each queue (queue 111 to queue 113) per second, is set to VI: VP: VB set in advance. Then, the control means 106 sets the PPS value of the highest priority packet sent from the queue I (queue 111) as X × VI / (VI + VP + VB). The control means 106 sets the PPS value of the packet with the second highest priority sent from the queue P (queue 112) storing the packet with the second highest priority including the P frame to X × VP. Set as / (VI + VP + VB). The control means 106 sets the PPS value of the lowest priority packet sent from the queue B (queue 113) storing the lowest priority packet including the B frame as X × VB / (VI + VP + VB). And the control means 106 sends out the packet stored in each queue (queue 111-queue 113) to the communication part 23 based on each set PPS value. The preset threshold value can be arbitrarily set.

  Specifically, for example, the ratio of PPS that is the number of packets transmitted from each queue (queue 111 to queue 113) of the video category (AC_VI) illustrated in FIG. 7 is set to 5: 3: 2 in advance. It is assumed that the actual PPS calculated by the detecting unit 105 of the communication unit 23 is 20000. In this case, the PPS value, which is the number of packets transmitted from each queue (queue 111 to queue 113) of the video category (AC_VI), is calculated and set as follows based on the above calculation.

PPS value of queue I (queue 111) = (20000 × 5) / (5 + 3 + 2) = 10000 packets / second PPS value of queue P (queue 112) = (20000 × 3) / (5 + 3 + 2) = 6000 packets / second Queue B PPS value of (queue 113) = (20000 × 2) / (5 + 3 + 2) = 4000 packets / second

  Based on the PPS value calculated in this way, the control means 106 sends the packet transmission rate from the queue I (queue 111) storing the highest priority packet including the I frame to the communication unit 23 at 10,000 packets / second. Output. The control means 106 outputs the packet transmission rate from the queue P (queue 112) storing packets of the highest priority next to the highest priority including the P frame to the communication unit 23 at 6000 packets / second. The control means 106 outputs the packet transmission rate from the queue B (queue 113) storing the lowest priority packets including the B frame to the communication unit 23 at 4000 packets / second.

  Then, the communication unit 23 wirelessly transfers each packet sent from each queue (queue 111 to queue 113) storing packets classified into the video category (AC_VI) by the CSMA / CA method.

  As described above, the control unit 106 of the information processing apparatus 10 according to the present embodiment uses the monitoring unit 107 described later to count the number of packets stored in the queue I (queue 111) that stores the highest priority packets including the I frame. If the threshold does not exceed a preset threshold value, the ratio of PPS of packets sent from each queue (queue 111 to queue 113) is set to a preset value in order of priority. Thereby, the information processing apparatus 10 can improve the video quality by suppressing the delay of the high-priority video frame (I frame).

  Further, the control means 106 sets the number of packets stored in the queue I (queue 111) for storing the highest priority packets including the I frame in advance as shown in FIG. When the threshold value is exceeded, the ratio of PPS, which is the number of packets transmitted from each queue (queue 111 to queue 113) per second, is set as (VI × Qwireless): VP: VB. The control means 106 sets the PPS value of the highest priority packet sent from the queue I (queue 111) as X × (VI × Qwireless) / ((VI × Qwireless) + VP + VB). The control means 106 sets the PPS value of the packet with the second highest priority sent from the queue P (queue 112) storing the packet with the second highest priority including the P frame to X × VP. / ((VI × Qwireless) + VP + VB). The control means 106 sets the PPS value of the lowest priority packet sent from the queue B (queue 113) storing the lowest priority packet including the B frame as X × VB / ((VI × Qwireless) + VP + VB). . And the control means 106 sends out the packet stored in each queue (queue 111-queue 113) to the communication part 23 based on each set PPS value. The preset threshold value can be arbitrarily set.

  Specifically, for example, the ratio of PPS that is the number of packets transmitted from each queue (queue 111 to queue 113) of the video category (AC_VI) illustrated in FIG. 8 is set to 5: 3: 2 in advance. Further, the set value of the S / N ratio min is 9 dB, and the value of the S / N ratio max is 57 dB. Then, it is assumed that the value of the S / N ratio mea calculated by the detection unit 105 of the communication unit 23 is 21 dB, and the actual PPS calculated from the detected transmission rate is 20000 packets / second. In this case, the PPS value, which is the number of packets transmitted from each queue (queue 111 to queue 113) of the video category (AC_VI), is calculated and set as follows based on the above calculation.

First, the control means 106 calculates the PPS ratio from the preset 5: 3: 2 as follows, and changes and sets the PPS ratio.
Ratio of new PPS of each queue buffer = 5 × ((57-9) / (21-9)): 3: 2≈20: 3: 2

PPS value of queue I (queue 111) = (20000 × 20) / (20 + 3 + 2) = 16000 packets / second PPS value of queue P (queue 112) = (20000 × 3) / (20 + 3 + 2) = 2400 packets / second Queue B PPS value of (queue 113) = (20000 × 2) / (20 + 3 + 2) = 1600 packets / second

  Based on the PPS value calculated in this way, the control means 106 sends the packet transmission rate from the queue I (queue 111) storing the highest priority packet including the I frame to the communication unit 23 at 16000 packets / second. Output. The control means 106 outputs the packet transmission rate from the queue P (queue 112) storing packets of the highest priority next to the highest priority including the P frame to the communication unit 23 at 2000 packets / second. The control means 106 outputs the packet transmission rate from the queue B (queue 113) storing the lowest priority packets including the B frame to the communication unit 23 at 1300 packets / second.

  Then, the communication unit 23 wirelessly transfers each packet sent from each queue (queue 111 to queue 113) storing packets classified into the video category (AC_VI) by the CSMA / CA method.

  As described above, the control unit 106 causes the monitoring unit 107 to be described later when the number of packets stored in the queue I (queue 111) storing the highest priority packet including the I frame exceeds a preset threshold value. By setting a large packet output rate (PPS) from queue I (queue 111), it is possible to improve video quality by suppressing delay of video frames (I frames) with high priority.

  Returning to FIG. 2, the monitoring unit 107 monitors the number of packets stored in a plurality of queues storing packets classified into the video category (AC_VI). Then, the monitoring unit 107 notifies the video queue size changing unit 25 of the result of the number of packets stored in the plurality of monitored queues.

  The video queue size changing unit 25 includes a determining unit 108 and a changing unit 109. The determination unit 108 determines the packet storage status of a plurality of queues that store packets. Specifically, the determination unit 108 includes a queue I (queue 111) that stores the highest priority packet including the I frame, and a queue P (that stores the second highest priority packet including the P frame. Queue 112) and queue B (queue 113) storing the lowest priority packets including B frames are monitored. Then, it is determined whether or not there is a space for storing a new highest priority packet in the queue I (queue 111) that stores the highest priority packet. Further, it is determined whether or not each queue (queue 111 to queue 113) storing packets from the highest priority to the lowest priority has a space for storing a new packet.

  The changing unit 109 changes the sizes of a plurality of queues (queues 111 to 113) that store packets classified into the video category (AC_VI). Specifically, the changing unit 109 includes a queue I (queue 111) that stores packets including I frames, a queue P (queue 112) that stores packets with the highest priority after the highest priority including P frames, The number of stages of each buffer of the queue B (queue 113) storing the lowest priority packet including the B frame is increased or decreased.

  When the determining unit 108 determines that the queue I (queue 111) storing the highest priority packet has a space for storing a new highest priority packet, the changing unit 109 determines that there are a plurality of queues (queues 111 to 111). The number of buffer stages of the queue 113) is set to a preset number of buffer stages.

  Next, a method for changing the number of buffer stages of a plurality of queues (queues 111 to 113) by the changing unit 109 will be described. 9-12 is a figure which shows an example of a functional structure of the radio | wireless part of the information processing apparatus which concerns on this Embodiment. 9 to 12 have the same configuration as that of FIG. 2, the same reference numerals are attached and detailed description thereof is omitted. 9 to 12, for example, a plurality of queues include a queue I (queue 111) for storing the highest priority packet, and a queue P (queue 112) for storing the second highest priority packet. A case where the queue is a queue B (queue 113) storing a packet with the lowest priority will be described as an example.

  First, with reference to FIG. 9 and FIG. 10, a case where the newly input packet 114 is a highest priority packet including an I frame will be described as an example. The changing unit 109 determines that the queue I (queue 111) storing the highest priority packet does not have a space for storing the new highest priority packet 114 as shown in FIG. 9 by the determining unit 108. In this case, as shown in FIG. 10, the size of the queue B (queue 113) for storing the lowest priority packet is changed to a smaller size, and the size of the queue I (queue 111) for storing the highest priority packet is changed to a larger size. .

  That is, as shown in FIG. 10, the changing means 109 reduces the number of buffer stages of the queue B (queue 113) storing the lowest priority packet from the preset buffer stage number, for example, by one stage, The setting is changed so that, for example, the number of stages of the buffer of queue I (queue 111) for storing the highest priority packet is increased from the preset number of stages of the buffer. Then, the storage unit 104 stores the new highest priority packet 114 in the queue I (queue 111) that stores the highest priority packet.

  In FIG. 10, the new packet 114 is the highest priority packet including the I frame, and the changing means 109 has preset the number of buffer stages of the queue I (queue 111) for storing the highest priority packet. An example is shown in which the setting is changed so as to increase the number of stages by one from the number of stages of the buffer.

  Thus, when the newly input packet is the highest priority packet, the storage unit 104 stores the highest priority packet including the I frame in the queue I (queue 111) without discarding the packet. Can do. Therefore, the information processing apparatus 10 according to the present embodiment can improve the video quality.

  Next, with reference to FIG. 11 and FIG. 12, a case where the newly input packet 114 is a packet other than the lowest priority including the B frame will be described as an example. As shown in FIG. 11, the changing unit 109 has a space for storing a new packet 114 in each of the queues (queues 111 to 113) that store the packets from the highest priority to the lowest priority. If the new packet 114 is a packet other than the lowest priority, as shown in FIG. 12, one lowest priority packet is sent from the queue B (queue 113) in which the lowest priority packet is stored. , The size of the queue B (queue 113) storing the lowest priority packet is changed to a smaller size, and the size of the queue I (queue 111) storing the new packet is changed to a larger size.

  That is, as shown in FIG. 12, the changing unit 109 discards, for example, one lowest priority packet from the queue B (queue 113) storing the lowest priority packet. Thereafter, the changing unit 109 decreases the number of stages of the buffer of the queue B (queue 113) storing the lowest priority packet from the preset number of stages of the buffer, for example, by one. Then, the changing unit 109 preliminarily sets the number of buffer stages of the queue I (queue 111) storing the highest priority packet or the queue P (queue 112) storing the second highest priority packet. For example, the setting is changed so as to increase the number of stages by one from the set number of stages of the buffer. Then, the storage unit 104 stores a packet 114 other than the new lowest priority, for example, a queue I (queue 111) for storing the highest priority packet or a queue for storing the packet with the second highest priority after the highest priority. Store in P (queue 112). When the information processing apparatus 10 must always discard the packet, the information processing apparatus 10 first discards the lowest priority packet including the video frame (B frame) with low importance. Accordingly, it is possible to suppress the discarding of the highest priority packet including a video frame (I frame) having a high importance level, or a packet having the second highest priority level after the highest priority, thereby improving the video quality. .

  In FIG. 12, the new packet 114 is the highest priority packet including the I frame, and the changing means 109 has preset the number of stages of the buffer of the queue I (queue 111) storing the highest priority packet. An example is shown in which the setting is changed so as to increase the number of stages by one from the number of stages of the buffer.

  As a result, the storage means 104 allows the highest priority packet or P frame including the I frame even when the newly input packet is the highest priority packet or the highest priority packet next to the highest priority. Can be stored in the queue I (queue 111) or the queue P (queue 112) without being discarded. Therefore, the information processing apparatus 10 according to the present embodiment can improve the video quality.

  The information processing apparatus 10 according to the present embodiment receives a packet including at least a part of a frame of video data. The information processing apparatus 10 determines the frame type of the video data by analyzing the service type field of the received packet. The information processing apparatus 10 redefines the ToS (Type of Service) field in the packet header as a DS (DiffServ) field for a packet including at least a part of the frame of the video data, and the frame type corresponds to the video quality. A plurality of priorities are set in descending order of the frame type. Then, the information processing apparatus 10 stores the packet for which the priority is set in a queue corresponding to each priority. The information processing apparatus 10 determines the packet storage status of a plurality of queues that store packets, and detects the communication status of the packets stored in the queue. Then, the information processing apparatus 10 controls transmission of the packets stored in the plurality of queues based on the detected communication status and the set packet priority.

  As a result, the information processing apparatus 10 sets a high priority to a packet including a frame having a large contribution to the video quality, stores the packet in a plurality of queues for each priority order, and stores the high priority video. A packet including a frame of data can be transmitted with the highest priority. Therefore, it is possible to improve internal video quality by reducing internal collision of high-priority transmission frames and suppressing delay and discard of high-priority video frames.

  Next, with reference to FIG. 13, the control operation in the information processing apparatus 10 according to the present embodiment will be described. FIG. 13 is a flowchart illustrating an example of a control operation of the information processing apparatus according to the present embodiment.

  The information processing apparatus 10 controls each queue buffer (queue 111 to queue 113) that stores packets classified into the video category (AC_VI) under the control of the video output control unit 24 and the video queue size changing unit 25 of the wireless unit 14. And the ratio of PPS that is the number of packets sent from each queue (queue 111 to queue 113) of the video category (AC_VI) is set (step S11).

  The information processing apparatus 10 receives a newly input packet (step S12). The information processing apparatus 10 determines whether or not the received new packet is a packet classified into the video category (AC_VI) (step S13). When the newly input packet is a packet classified into the video category (AC_VI) (step S13: YES), the information processing apparatus 10 redefines the priority for the input packet for each video frame type. (Step S14). That is, a plurality of priorities are set for a packet including at least a part of a frame of video data in order of the frame type in which the frame type has a large contribution to the video quality.

  If the newly input packet is not a packet classified into the video category (AC_VI) (step S13: NO), the information processing apparatus 10 stores the input packet in the corresponding queue, and then proceeds to step S21. To continue processing.

  Next, the information processing apparatus 10 determines whether or not the input packet is an I frame (step S15). If the input packet is an I frame (step S15: YES), the information processing apparatus 10 determines whether or not there is a space for storing a new packet in the queue storing the highest priority packet including the I frame. Determination is made (step S16). If the input packet is not an I frame (step S15: NO), the information processing apparatus 10 proceeds to step S20 and continues the process.

  Next, when there is an empty space for storing a new packet in the queue storing the highest priority packet including the I frame (step S16: YES), the information processing apparatus 10 sets the new packet to the highest priority including the I frame. Then, it is determined whether the number of packets stored in the queue storing the highest priority packet including the I frame exceeds a preset threshold value (step S17).

  When there is no space for storing a new packet in the queue storing the highest priority packet including the I frame (step S16: NO), the information processing apparatus 10 determines the number of buffer stages of the queue storing the lowest priority packet. From the preset number of buffer stages, for example, one stage number is reduced, and the number of buffer stages of the queue storing the highest priority packets is increased from the preset buffer stage number, for example, one stage number. After changing the setting, the highest priority packet including a new I frame is stored (step S18), and the process proceeds to step S19.

  Next, when the number of packets stored in the queue storing the highest priority packets including the I frame exceeds a preset threshold value (step S17: YES), the information processing apparatus 10 calculates the calculated S / N. Based on the ratio, the ratio of PPS that is the number of packets transmitted from each queue of the video category (AC_VI) is changed (step S19).

  When the number of packets stored in the queue storing the highest priority packets including the I frame does not exceed the preset threshold value (step S17: NO), the information processing apparatus 10 proceeds to step S20 and performs the process. continue.

  Next, the information processing apparatus 10 uses a preset PPS ratio and the calculated actual PPS value to store a plurality of queues (queues 111 to Queue) that store packets classified into the video category (AC_VI). 113), the sending speed for sending each packet is set, and the packet is sent to the communication unit 23 (step S20).

  Then, the communication unit 23 transfers each packet sent from a plurality of queues storing packets classified into the video category (AC_VI) via the CSMA / CA method (step S21) and ends the process. .

  In this manner, the information processing apparatus 10 according to the present embodiment performs the processing operation described above. Thereby, the information processing apparatus 10 according to the present embodiment analyzes the service type field of the received packet to determine the frame type of the video data. The information processing apparatus 10 redefines the ToS (Type of Service) field in the packet header as a DS (DiffServ) field for a packet including at least a part of the frame of the video data, and the frame type corresponds to the video quality. A plurality of priorities are set in descending order of the frame type. Then, a packet including at least a part of a frame of video data whose priority is redefined is stored in a queue corresponding to the priority for each frame type. Therefore, the information processing apparatus 10 according to the present embodiment is a frame whose frame type has a large contribution to the video quality with respect to a packet including at least a part of a frame of video data classified into the video category (AC_VI). Since a plurality of priorities are set in order of type, it is possible to differentiate packets with high importance from those with low importance.

  In addition, the information processing apparatus 10 according to the present embodiment has a plurality of packets when the number of packets stored in the queue (queue 111) storing the highest priority packets including the I frame does not exceed a preset threshold. The PPS ratio of packets sent from the queue (queue 111 to queue 113) is set to a preset value in order of priority. If the number of packets stored in the queue (queue 111) storing the highest priority packets including I frames exceeds a preset threshold, the packet output speed (PPS) from the queue (queue 111) is set. Set larger. Therefore, the information processing apparatus 10 according to the present embodiment can improve video quality by suppressing delay of video frames (I frames) with high priority.

  Further, the information processing apparatus 10 according to the present embodiment, when it is determined that there is no space for storing the new highest priority packet 114 in the queue (queue 111) storing the highest priority packet, the lowest priority The size of the queue (queue 113) that stores the packets of the highest priority is changed to a smaller size, and the size of the queue (queue 111) that stores the highest priority packets is changed to a larger size. Then, the new highest priority packet 114 is stored in the queue (queue 111) that stores the highest priority packet. Therefore, when the newly input packet is the highest priority packet, the highest priority packet including the I frame can be stored in the queue corresponding to the priority without being discarded. Therefore, the information processing apparatus 10 according to the present embodiment can improve video quality.

  Further, the information processing apparatus 10 according to the present embodiment has no space for storing new packets 114 in all of the plurality of queues (queues 111 to 113) that store packets from the highest priority to the lowest priority. If it is determined that the new packet 114 is a packet other than the lowest priority, one lowest priority packet is discarded from the queue (queue 113) in which the lowest priority packet is stored. Thereafter, the information processing apparatus 10 changes the size of the queue (queue 113) that stores the lowest priority packet to a smaller size, and greatly changes the size of the queue (queue 111) that stores the new packet. Then, the storage unit 104 stores the packet 114 other than the new lowest priority, for example, in the queue I (queue 111) that stores the highest priority packet. Therefore, even if the newly input packet is the highest priority packet or the highest priority packet next to the highest priority, the highest priority packet including the I frame or the highest priority packet including the P frame is used. The next highest priority packet can be stored in queue I (queue 111) or queue P (queue 112) without being discarded. Therefore, the information processing apparatus 10 according to the present embodiment can improve video quality.

  As mentioned above, although embodiment of this invention was described, each above-mentioned embodiment is shown as an example and is not intending limiting the range of invention. The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the components without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the above-described embodiments. For example, some components may be deleted from all the components shown in the embodiment. Further, the above embodiments and modifications can be arbitrarily combined.

  The control program executed by the information processing apparatus 10 of each of the above-described embodiments is a file in an installable format or an executable format, and is a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital The recording medium may be recorded on a computer-readable recording medium such as Versatile Disk).

  Further, the control program executed by the information processing apparatus 10 according to each of the above-described embodiments may be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network. Good. Moreover, you may comprise so that the control program run with the information processing apparatus 10 of each above-mentioned embodiment may be provided or distributed via networks, such as the internet.

10 Information processing apparatus 11 CPU
12 Application processing unit 13 Memory 14 Radio unit 15 Antenna 16 Bus line 21 Input control unit 22 Queue / buffer unit 23 Communication unit 24 Video output control unit 25 Video queue size changing unit 31 Service type field 101 Accepting unit 102 Discriminating unit 103 Setting unit 104 storage means 105 detection means 106 control means 107 monitoring means 108 determination means 109 change means 111 queue for storing packets including I frames 112 queue for storing packets including P frames 113 queue for storing packets including B frames 114 queues for storing packets including B frames 121, 126 DIFS
122, 127 Backoff 123, 128 Data transmission 124 SIFS
125 Ack

JP 2008-67350 A

Claims (10)

Receiving means for receiving a packet including at least a part of a frame of video data;
Determining means for determining a frame type corresponding to at least a part of a frame included in the packet received by the receiving means;
Setting means for setting a plurality of priorities in order of the frame type in which the frame type has a large contribution to the video quality with respect to the packet in which the frame type is determined;
Storage means for storing the packet according to the priority set by the setting means in a plurality of queues associated with a plurality of priorities that can be set by the setting means;
Detecting means for detecting a communication status of the packet stored in the queue;
Control means for controlling transmission of the packets stored in the plurality of queues based on the detected communication status and the set priority of the packets;
An information processing apparatus comprising:   The detecting means calculates an S / N ratio mea which is a signal-to-noise ratio of a packet stored in the queue based on a communication state of the packet, and a PPS (Packet Per Second) which is the number of packets which can be processed per second. The information processing apparatus according to claim 1, wherein the information processing apparatus calculates the information processing apparatus. The detection means uses a preset allowable maximum S / N ratio max and allowable minimum S / N ratio min and the calculated S / N ratio mea to determine the wireless communication status parameter Qwireless by the following equation (1). The information processing apparatus according to claim 1, wherein the information processing apparatus is calculated from

Monitoring means for monitoring the number of packets stored in the queue;
The calculated PPS is X packets / second, and the queue is a queue I storing the highest priority packet, a queue P storing the second highest priority packet, and the lowest When the queue B stores the packets of the priority,
When the number of packets stored in the queue I does not exceed the threshold, the control means sets VI: VP: VB as a preset ratio of PPS, which is the number of packets transmitted from each queue per second,
The PPS value of the packet sent from the queue I is set to X × VI / (VI + VP + VB), the PPS value of the packet sent from the queue P is set to X × VP / (VI + VP + VB), and the queue B Set the PPS value of the packet to be sent as X × VB / (VI + VP + VB),
When the number of packets stored in the queue I exceeds the threshold, the ratio of PPS, which is the number of packets transmitted from each queue per second, is set as (VI × Qwireless): VP: VB,
The PPS value of the packet transmitted from the queue I is set as X × (VI × Qwireless) / ((VI × Qwireless) + VP + VB), and the PPS value of the packet transmitted from the queue P is set to X × VP / ((( (VI × Qwireless) + VP + VB), the packet PPS value transmitted from the queue B is set to X × VB / ((VI × Qwireless) + VP + VB), and the packet stored in each queue is transmitted. The information processing apparatus according to claim 1, wherein: Determining means for determining a packet storage status of the queue storing the packets;
A changing means for changing a size of a queue for storing the packet;
When the determination unit determines that the queue storing the highest priority packet does not have a space for storing a new highest priority packet, the changing unit determines the size of the queue storing the lowest priority packet. The information processing apparatus according to claim 1, wherein the size of the queue for storing packets of the highest priority is changed to a large value.   The changing means is determined by the determining means that there is no space for storing new packets in a plurality of queues storing the packets from the highest priority to the lowest priority, and the new packet has a value other than the lowest priority. If it is a packet, after discarding one lowest priority packet from the queue storing the lowest priority packet, change the size of the queue storing the lowest priority packet to a smaller size, The information processing apparatus according to claim 5, wherein the size of the queue to be stored is greatly changed.   The setting means redefines a ToS (Type of Service) field in a header of the packet as a DS (DiffServ) field, and sets priority-related information in the DS field for each frame type. The information processing apparatus according to claim 1. The video data is video data,
The frame type is any one of an I frame, a P frame, and a B frame defined in the MPEG standard, and the order of the frame type having a large contribution to the video quality is an order of I frame> P frame> B frame. The information processing apparatus according to claim 1, wherein the information processing apparatus is provided. An accepting step for accepting a packet including at least a part of a frame of video data;
A determination step of determining a frame type corresponding to at least a part of a frame included in the packet received in the reception step;
A setting step for setting a plurality of priorities in order of the frame type in which the frame type has a large contribution to the video quality with respect to the packet in which the frame type is determined;
A storage step of storing the packet according to the priority set by the setting step in a plurality of queues associated with the plurality of priorities that can be set by the setting step;
A detecting step of detecting a communication status of the packet stored in the queue;
A control step of controlling transmission of the packets stored in the plurality of queues based on the detected communication status and the set priority of the packets;
An information processing method comprising: In the information processing device,
An accepting step for accepting a packet including at least a part of a frame of video data;
A determination step of determining a frame type corresponding to at least a part of a frame included in the packet received in the reception step;
A setting step for setting a plurality of priorities in order of the frame type in which the frame type has a large contribution to the video quality with respect to the packet in which the frame type is determined;
A storage step of storing the packet according to the priority set by the setting step in a plurality of queues associated with the plurality of priorities that can be set by the setting step;
A detecting step of detecting a communication status of the packet stored in the queue;
A control step of controlling transmission of the packets stored in the plurality of queues based on the detected communication status and the set priority of the packets;
A program for running

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