WO2019065296A1

WO2019065296A1 - Communication control apparatus, communication control method, program, motion picture imaging communication terminal, and motion picture reproducing communication terminal

Info

Publication number: WO2019065296A1
Application number: PCT/JP2018/034128
Authority: WO
Inventors: 小川　一哉
Original assignee: ソニー株式会社
Priority date: 2017-09-29
Filing date: 2018-09-14
Publication date: 2019-04-04

Abstract

The present disclosure pertains to a communication control apparatus, a communication control method, a program, a motion picture imaging communication terminal, and a motion picture reproducing communication terminal, all of which enable suppression of power consumption during communication. This communication control apparatus acquires, from a wireless transmission device that transmits/receives motion picture data by performing transmission via wireless communication, a parameter correlated with a communication state and/or communication power, and restricts, according to said parameter, the quality of the motion picture data before an available communication band decreases as a result of deterioration in radio wave condition in a communication path. The communication control apparatus also imposes a limit on the compression ratio of the motion picture data acquired through imaging of a motion picture by an imaging device, or, when transmitting a request command to a motion picture distribution server, restricts the quality of the motion picture data requested to be distributed. The present technology is applicable to, for example, a reproducing terminal or an imaging terminal or having the function of transmitting or receiving motion picture data via wireless communication.

Description

Communication control apparatus, communication control method, program, moving image imaging communication terminal, and moving image reproduction communication terminal

The present disclosure relates to a communication control device, a communication control method, a program, a moving image imaging communication terminal, and a moving image reproduction communication terminal, and in particular, a communication control device and a communication control method which can suppress communication power. The present invention relates to a program, a video imaging communication terminal, and a video reproduction communication terminal.

In recent years, for example, for the purpose of application to surveillance cameras and action cameras, an imaging system having a wireless communication function of transferring data obtained by compressing captured moving images via a wireless communication system has been developed. There is. Also, for example, many playback systems have wireless communication functions, such as smartphones, that receive data distributed from a streaming server on a network via a wireless communication system and play moving images. It is being developed.

For example, in the communication system disclosed in Patent Document 1, when streaming data is transmitted by such a wireless communication system, if the fluctuation of the data transfer rate is large, it is optimal according to the communicable band of the communication path. Bit rate can be selected.

In addition, depending on the wireless communication method in the wireless communication system, generally, even when a predetermined communication band is secured, the consumption of communication power may increase due to the signal to interference ratio (SIR) of the communication path. there were. For example, in a wireless communication method in which the modulation method is selected to maintain the communication band from a plurality of modulation methods, or in a wireless communication method in which the transmission power is increased to maintain the communication band when the SIR is poor, communication is performed according to the SIR of the communication path. Power consumption may increase.

Therefore, as disclosed in Patent Document 2, when transmitting digital data using a transmission line such as a wireless LAN (Local Area Network), switching control of the data supply path is performed to reduce power consumption. A data transmission apparatus that can achieve

JP 2004-153620 A Unexamined-Japanese-Patent No. 2006-270695

By the way, in the communication system disclosed in Patent Document 1 described above, when the communication band starts to fall, more communication power may be consumed than when communicating in an environment with good radio wave conditions, and the communication of the system From the power point of view, it was not always the optimal system. Further, in the data transmission apparatus disclosed in Patent Document 2 described above, for example, although the power of the transcoder circuit portion is reduced, the power of the communication portion is not reduced, so It can not be said that consumption is optimized.

The present disclosure has been made in view of such a situation, and enables to reduce communication power.

A communication control apparatus according to a first aspect of the present disclosure acquires a parameter having a correlation with at least one of a communication state and communication power from a wireless transmission apparatus that transmits and receives moving image data by performing wireless communication. And a restricting unit for restricting the quality of the moving image data before the communicable band decreases with the deterioration of the radio wave condition of the communication path according to the parameter.

A communication control method or program according to a first aspect of the present disclosure acquires a parameter correlated with at least one of communication state and communication power from a wireless transmission device that transmits and receives moving image data by performing wireless communication. And limiting the quality of the moving image data before the communicable band decreases with the deterioration of the radio wave condition of the communication path according to the parameters.

In a first aspect of the present disclosure, a parameter correlated with at least one of communication state and communication power is acquired from a wireless transmission device that transmits and receives moving image data by performing wireless communication, and communication is performed according to the parameter The quality of the moving image data is limited before the communicable band decreases with the deterioration of the radio wave condition on the road.

A moving picture imaging communication terminal according to a second aspect of the present disclosure includes: an imaging apparatus for acquiring moving picture data by capturing a moving picture; and a wireless transmission apparatus for transmitting moving picture data by performing transmission by wireless communication; A parameter having a correlation with at least one of the communication state and the communication power is acquired from the wireless transmission device, and the moving image data is acquired before the communicable band decreases according to the parameter according to the deterioration of the radio wave condition of the communication path. And a control unit for limiting the quality.

In the second aspect of the present disclosure, moving image data is acquired by capturing a moving image, transmission by wireless communication is performed, and moving image data is transmitted, which has a correlation with at least one of communication state and communication power. A parameter is acquired, and according to the parameter, the quality of moving image data is limited before the communicable band decreases with the deterioration of the radio wave condition of the communication path.

A moving image reproduction communication terminal according to a third aspect of the present disclosure includes a display device that reproduces and displays a moving image, a wireless transmission device that performs transmission by wireless communication and receives moving image data, and the wireless transmission device. A control that acquires a parameter correlated with at least one of the communication state and the communication power, and limits the quality of the moving image data before the communicable band decreases according to the parameter according to the deterioration of the radio wave condition of the communication path. And transmitting the request command to the moving image distribution server for distributing the moving image data in order to reproduce and display the moving image through the wireless transmission device. Limit the quality of the requested moving image data.

In the third aspect of the present disclosure, a moving image is reproduced and displayed, transmission by wireless communication is performed, moving image data is received, and a parameter correlated with at least one of the communication state and the communication power is acquired, According to the parameters, the quality of moving image data is limited before the communicable band decreases with the deterioration of the radio wave condition of the communication path. Then, when transmitting a request command to the moving image distribution server that distributes moving image data in order to reproduce and display the moving image, the quality of moving image data for which distribution is requested is limited.

According to the first to third aspects of the present disclosure, communication power can be suppressed.

In addition, the effect described here is not necessarily limited, and may be any effect described in the present disclosure.

FIG. 1 is a block diagram showing a configuration example of an embodiment of a video imaging communication terminal to which the present technology is applied. It is a figure which shows the relationship between a communication zone | band and radio | wireless communication power. It is a figure which shows the relationship between SIR, a communication band, and wireless communication power. It is a figure explaining bit rate control. It is a flowchart explaining the 1st example of processing which controls consumption of communication power based on SIR. It is a flowchart explaining the 2nd processing example which controls consumption of communication power based on SIR. It is a flowchart explaining the 3rd processing example which controls consumption of communication power based on SIR. It is a figure which shows the relationship between SIR and a throughput. It is a figure explaining the multi-value level of MCS. It is a flowchart explaining the example of processing which controls consumption of communication power based on MCS. It is a flowchart explaining the example of processing which controls consumption of communication electric power based on communication electric power information. FIG. 1 is a block diagram showing a configuration example of an embodiment of a moving image reproduction communication terminal to which the present technology is applied. It is a block diagram which shows the structural example of a moving image delivery system. It is a flowchart explaining the example of processing which controls consumption of communication power based on SIR. It is a flowchart explaining the example of processing which controls consumption of communication electric power based on communication electric power information. Fig. 21 is a block diagram illustrating a configuration example of an embodiment of a computer to which the present technology is applied.

Hereinafter, specific embodiments to which the present technology is applied will be described in detail with reference to the drawings.

<Configuration example of moving image imaging communication terminal>
FIG. 1 is a block diagram showing a configuration example of an embodiment of a moving picture imaging communication terminal to which the present technology is applied.

The moving picture imaging communication terminal 11 shown in FIG. 1 has a function of capturing moving pictures and transmitting moving picture data obtained by compressing the moving pictures by wireless communication, and the imaging device 21, the image processing device 22, and the image compression A device 23, a wireless transmission device 24, a wireless antenna 25, and a control device 26 are provided.

The imaging device 21 includes, for example, an imaging device such as a complementary metal oxide semiconductor (CMOS) image sensor, and supplies to the image processing device 22 moving image data obtained by capturing a moving image by the imaging device. . For example, the imaging device 21 can start and stop the imaging in accordance with the imaging control information supplied from the control device 26, and a moving image of a predetermined frame rate and a predetermined image size set in the moving image pickup communication terminal 11. An image can be taken.

The image processing device 22 subjects the moving image data supplied from the imaging device 21 to various image processing such as development processing, correction processing, enlargement / compression processing and the like, and moving image data subjected to those image processing. Are supplied to the image compression device 23. For example, the image processing device 22 performs image processing to reduce the frame rate of moving image data, image processing to reduce the image size of moving image data, and the like according to the image processing control information supplied from the control device 26 It can be performed.

The image compression device 23 is an image such as JPEG (Joint Photographic Experts Group), MPEG 2 (Moving Picture Experts Group 2), H.264, H.265, etc. for moving image data subjected to image processing by the image processing device 22. The amount of data is compressed by encoding according to the encoding algorithm. Then, the image compression device 23 supplies the encoded moving image data to the wireless transmission device 24. At this time, the image compression device 23 can adjust the encoding bit rate (compression rate) at the time of encoding a moving image, and the encoding bit rate according to the compression rate control information supplied from the control device 26 The moving image data is encoded and the amount of data is compressed. The image compression device 23 can also encode moving image data of a frame rate and an image size in accordance with the compression rate control information supplied from the control device 26.

The wireless transmission device 24 can perform wireless communication with various wireless communication systems (specifically, WiFi / 3G / LTE, etc.) with, for example, a wireless communication base station (not shown), and the wireless communication can be performed by the wireless communication The moving image data supplied from the image compression device 23 is transmitted. Also, when performing wireless communication with the wireless communication base station, the wireless transmission device 24 performs communication band information indicating the communication band currently being used, and the communication state (channel state) and communication in wireless communication on the current communication path. It is possible to acquire at least one of the power and the communication parameter having correlation (association), and supply the acquired communication band information and communication parameter to the control device 26.

For example, in the moving picture imaging communication terminal 11, as communication parameters, SIR indicating the ratio of interference power to signal power in the current communication channel, MCS (Modulation and Coding Set) indicating the modulation scheme in the current communication channel, current Communication power information indicating communication power consumed to perform wireless communication in the communication path is used.

The wireless antenna 25 emits a stream signal of moving image data transmitted by the wireless transmission device 24 into space as an electromagnetic wave, and transmits moving image data to, for example, a wireless base station (not shown).

The control device 26 can control the entire moving image imaging communication terminal 11 by using the imaging control information, the image processing control information, and the compression rate control information as described above. For example, the control device 26 acquires communication parameters (SIR, MCS, or communication power information) from the wireless transmission device 24, and before the communicable band is lowered due to deterioration of the radio wave condition of the communication path, moving image data Control to limit the quality of the image (compression rate, frame rate, image size, etc.). Thereby, the control device 26 can suppress the communication power.

<Reduction of communication power based on SIR>
The control for suppressing the consumption of communication power based on the SIR will be described with reference to FIGS. 2 to 4.

FIG. 2 shows a general relationship between a communication band (bit rate) and communication power when the radio wave condition of the communication path is sufficiently good. As shown in FIG. 2, the communication power consumed by the wireless communication is proportional to the communication band, and when the radio wave condition of the communication path is sufficiently good, the communication power increases or decreases according to the amount of data to be transmitted per unit time. It will be.

On the other hand, when the radio wave condition of the communication path is deteriorated and the SIR is lowered, the communication power consumed by the wireless communication may increase without being proportional to the communication band.

FIG. 3 shows the relationship between SIR and communication band (bit rate) and the relationship between SIR and communication power.

In general, the moving picture imaging communication terminal 11 can perform wireless communication in a sufficiently good radio wave condition near the wireless communication base station. For example, as shown in FIG. 3, in the SIR value ST where the SIR is sufficiently large, wireless communication is performed in the designated band b0, which is the designated communication band, with the minimum power p0 having the smallest communication power. In addition, the moving image imaging communication terminal 11 changes the vicinity of the minimum power p0 from the SIR value ST to a predetermined SIR value s0 which can perform wireless communication in the designated band b0 without increasing the communication power. Wireless communication can be performed.

Then, for example, when the moving picture imaging communication terminal 11 gets worse in the radio wave condition of the communication path as it leaves the wireless communication base station and the SIR becomes smaller than the SIR value s 0, the communication power is increased from the minimum power p 0 Communication control is performed to maintain the communication band of the designated band b0. For example, the moving picture imaging communication terminal 11 performs communication control such as changing the modulation scheme or increasing the transmission power, so that the radio wave condition of the communication path is such that the SIR becomes smaller than the SIR value s0. Even in this case, the communication band of the designated band b0 can be maintained.

Therefore, in this case, as shown in FIG. 3, while the communication band maintains the designated band b0, the communication power increases as the SIR value s0 decreases. Then, from the SIR value s0, the moving picture imaging communication terminal 11 has a predetermined SIR which is the upper limit of the communication power necessary to perform the maximum communication control such as changing the modulation scheme or increasing the transmission power. The communication power can be increased according to the SIR up to the value s1.

Furthermore, when the radio wave condition of the communication path continues to deteriorate and becomes smaller than the SIR value s1, the moving picture imaging communication terminal 11 performs maximum communication control such as changing the modulation scheme or increasing the transmission power. Even if it does, it becomes difficult to maintain the communication band of the designated band b0. Therefore, in this case, as shown in FIG. 3, the communication bandwidth decreases as the SIR value s0 decreases.

As described above, in the radio wave condition of the communication path where the communication band and the communication power change according to the SIR according to the radio wave condition of the communication path and the SIR is between the SIR value s0 and the SIR value s1, the communication power is increased or decreased. As a result, the communication band of the designated band b0 is maintained.

On the other hand, when the radio wave condition of the communication path is deteriorated such that the SIR becomes smaller than the SIR value s1, maximum communication control is performed to change the modulation scheme or increase the transmission power. It is considered that using the upper limit communication power necessary for the power consumption is not appropriate. Therefore, the control device 26 monitors the SIR of the transmission path via the radio transmission device 24. For example, before the communication band falls from the designated band b0, that is, even if the SIR is larger than the SIR value s1, Control is performed to limit the compression rate by the image compression device 23. By reducing the amount of coded bits in this way, it is possible to avoid an increase in communication power before the communication bandwidth decreases, and as a result, it is possible to suppress communication power. Therefore, the consumption of communication power can be optimized as a whole of the video imaging communication terminal 11.

For example, the control device 26 sets, as a threshold value, an SIR determination reference value which is equal to or greater than the SIR value s0 and less than the SIR value s1, and when the SIR becomes smaller than the SIR determination reference value Control is performed to reduce the coding bit rate of data.

For example, in the case of a mode in which priority is given to suppression of power consumption, the SIR determination reference value is set in the vicinity (including s0) of the SIR value s0 between the SIR value s0 and the SIR value s1. Further, the SIR judgment reference value is set in the vicinity (larger than s0) of the SIR value s1 between the SIR value s0 and the SIR value s1 in the mode in which priority is given to transmission of a higher quality moving image. Ru. The SIR determination reference value may be set to the moving image imaging communication terminal 11 from the outside using a network or the like.

Bit rate control by the controller 26 will be described with reference to FIG.

Similar to FIG. 3, FIG. 4 shows the relationship between SIR and communication band (bit rate) and the relationship between SIR and communication power. Further, in the example shown in FIG. 4, the above-described SIR determination reference value is set to the SIR value s0.

As shown in FIG. 4, in a state where the SIR of the communication path is sufficiently good, the moving picture imaging communication terminal 11 operates with the designated band b0 (or the maximum bit rate within the communicable band) and the minimum power p0. ing. In this state, it is assumed that the SIR of the communication channel changes with the movement of the moving picture imaging communication terminal 11, and the SIR becomes smaller than the SIR value s0 set as the SIR judgment reference value. At this time, even if communication in the designated band b0 is possible as the communicable band, the control device 26 performs moving image to perform communication in the limited band b0 'limited to the communication band smaller than the designated band b0. Control is performed on the image compression device 23 to reduce the data encoding bit rate.

After that, when the SIR improves and the SIR of the communication channel becomes larger than the SIR value s0 set as the SIR determination reference value, the control device 26 controls so as not to limit the compression ratio of the moving image. Do. Therefore, the control device 26 can control the image compression device 23 so as to restore the coding bit rate of the moving image data, and can return to communication in the designated band b0.

A first process example for suppressing the consumption of communication power based on the SIR will be described with reference to the flowchart of FIG.

For example, the control device 26 supplies imaging control information for instructing the imaging device 21 to start capturing a moving image, and processing is performed periodically when moving image data is output from the imaging device 21. In step S11, the control device 26 obtains the SIR from the communication parameters supplied from the wireless transmission device 24.

In step S12, the control device 26 determines whether the SIR according to the current radio wave condition of the communication path is larger than the SIR determination reference value. Here, as the SIR determination reference value, the SIR value s0 described with reference to FIG. 4 may be used, or an SIR value (SIR value s1) set from the outside in advance for the moving picture imaging communication terminal 11 Larger values and SIR values less than or equal to s 0) may be used.

If it is determined in step S12 that the current SIR is larger than the SIR determination reference value, the process proceeds to step S13. That is, in this case, it is determined that the radio wave condition of the communication path is good and there is no possibility that the communication power may increase. Therefore, the control device 26 limits the encoding bit rate when encoding moving image data. It is decided to use the designated band b0 (see FIG. 4) without performing it.

On the other hand, if it is determined in step S12 that the current SIR is not larger than (is equal to or less than) the SIR determination reference value, the process proceeds to step S14. That is, in this case, it is determined that the communication power may be increased as the radio wave condition of the communication channel is deteriorated. Therefore, the control device 26 is configured to encode the moving image data. , And decide to use the limited band b0 '(see FIG. 4).

After the process of step S13 or S14, the process proceeds to step S15, and the control device 26 sets, as the compression rate control information, a target encoding bit rate when encoding moving image data. For example, when the process of step S13 is performed, the control device 26 sets the designated band b0 to the compression rate control information, and when the process of step S14 is performed, the limited band b0 'is compressed. Set in control information.

In step S16, the control device 26 supplies, to the image compression device 23, the compression rate control information in which the target encoding bit rate is set in step S15. As a result, the control device 26 can control the image compression device 23 to encode moving image data at a target encoding bit rate, and then the process is ended.

As described above, the control device 26 can reduce the amount of coding bits by reducing the coding bit rate of moving image data, and therefore avoids an increase in communication power before the communication bandwidth decreases. As a result, communication power can be reduced.

A second process example for suppressing the consumption of communication power based on the SIR will be described with reference to the flowchart of FIG.

For example, in steps S21 and S22, the same processes as steps S11 and S12 in FIG. 5 are performed.

If it is determined in step S22 that the current SIR is larger than the SIR determination reference value, the process proceeds to step S23. In this case, the control device 26 does not limit the frame rate of moving image data to be transmitted from the moving image imaging communication terminal 11, and a predetermined frame rate (for example, Decide to use 120 fps).

On the other hand, when it is determined in step S22 that the current SIR is not larger than (is less than) the SIR determination reference value, the process proceeds to step S24. In this case, the control device 26 places a limit on the frame rate of moving image data to be transmitted from the moving image imaging communication terminal 11, and reduces the frame rate lower than the frame rate originally set in the moving image imaging communication terminal 11 (for example, To use 60 fps).

After the process of step S23 or S24, the process proceeds to step S25, and a desired frame rate is set in the image processing control information and the compression rate control information. For example, the control device 26 sets a predetermined frame rate in the image processing control information and the compression rate control information when the process of step S23 is performed, and reduces the process when the process of step S24 is performed. The set frame rate is set in the image processing control information and the compression rate control information.

In step S26, the control device 26 supplies the image processing control information and the compression rate control information for which the frame rate is set in step S25 to the image processing device 22 and the image compression device 23, respectively. Thereby, the control device 26 can control the image processing device 22 so as to perform the image processing with the predetermined frame rate or to perform the image processing to reduce the frame rate. Then, the control device 26 can control the image compression device 23 so as to encode the image data of the frame rate subjected to the image processing in the image processing device 22, and then the process is ended. .

As described above, since the control device 26 can reduce the encoding bit amount by reducing the frame rate of moving image data, it is possible to avoid an increase in communication power before the communication band decreases. As a result, communication power can be reduced.

A third processing example for suppressing the consumption of communication power based on the SIR will be described with reference to the flowchart of FIG.

For example, in steps S31 and S32, processing similar to that of steps S11 and S12 in FIG. 5 is performed.

Then, if it is determined in step S32 that the current SIR is larger than the SIR determination reference value, the process proceeds to step S33. In this case, the control device 26 does not change the image size of the moving image data to be transmitted from the moving image imaging communication terminal 11, and the original image size (for example, It is decided to use the pixel number 3840 × 2160).

On the other hand, when it is determined in step S32 that the current SIR is not larger than (is equal to or less than) the SIR determination reference value, the process proceeds to step S34. In this case, the control device 26 changes the image size of the moving image data transmitted from the moving image imaging communication terminal 11, and reduces the image size reduced from the original image size set from the beginning to the moving image imaging communication terminal 11 For example, it is decided to use the number of pixels 1920 × 1080).

After the process of step S33 or S34, the process proceeds to step S35, and a desired image size is set in the image processing control information and the compression rate control information. For example, the control device 26 sets the original image size in the image processing control information and the compression rate control information when the process of step S33 is performed, and reduces the size when the process of step S34 is performed. The set image size is set in the image processing control information and the compression rate control information.

In step S36, the control device 26 supplies the image processing control information and the compression rate control information for which the image size is set in step S35 to the image processing device 22 and the image compression device 23, respectively. Thus, the control device 26 may control the image processing device 22 to perform image processing with the original image size as it is or to perform image processing to reduce the image size from the original. it can. Then, the control device 26 can control the image compression device 23 so as to encode the image data of the image size subjected to the image processing in the image processing device 22, and then the process is ended. .

As described above, the control device 26 can reduce the encoding bit amount by reducing the image size of the moving image data, so that the increase in communication power can be avoided before the communication bandwidth decreases. As a result, communication power can be reduced.

<Reduction of communication power based on MCS>
Control for reducing the consumption of communication power based on MCS will be described with reference to FIGS. 8 and 9. FIG. 8 shows the relationship between SIR and throughput, and FIG. 9 shows multiple levels of MCS.

For example, the control device 26 can use MCS as well as SIR as a parameter for determining the status of the wireless communication channel.

For example, as shown in FIG. 8, the moving picture imaging communication terminal 11 can perform communication while changing the modulation method in accordance with the condition of the communication channel. The modulation scheme is expressed by a parameter called MCS. When the SIR is large, MCS with a large multilevel is set, and when the SIR is small, MCS with a small multilevel is set. As shown in the lower side of FIG. 9, the throughput is small in the modulation method with small multilevels, and the throughput is large in the method with large multilevels as shown in the upper side of FIG. Therefore, as the power for transferring the same amount of data, the smaller the multi-value level, the more power is required.

A process example of suppressing the consumption of communication power based on the MCS will be described with reference to the flowchart of FIG.

For example, the control device 26 supplies imaging control information for instructing the imaging device 21 to start capturing a moving image, and processing is performed periodically when moving image data is output from the imaging device 21. In step S41, the control device 26 obtains the MCS used in the current communication from the communication parameters supplied from the wireless transmission device 24.

In step S42, the control device 26 determines whether the multilevel level of the MCS used in the current communication is "large".

If it is determined in step S42 that the current multi-level MCS is "high", the process proceeds to step S43. That is, in this case, it is determined that the radio wave condition of the communication path is good and there is no possibility that the communication power may increase. Therefore, the control device 26 limits the encoding bit rate when encoding moving image data. It is decided to use the designated band b0 (see FIG. 4) without performing it.

On the other hand, if it is determined in step S42 that the current MCS multilevel is not "high", the process proceeds to step S44, and control device 26 determines that the MCS multilevel used in the current communication is It is determined whether it is "medium".

If it is determined in step S44 that the current multi-level MCS is "medium", the process proceeds to step S45. That is, in this case, it is determined that the radio wave condition of the communication path is not good but the possibility that the communication power is increased is low. Therefore, the control device 26 sets the coding bit rate at the time of coding moving image data. With a degree of restriction, it is decided to use a medium limit band (for example, a band intermediate between the designated band b0 and the limit band b0 'in FIG. 4).

On the other hand, when it is determined in step S44 that the current multilevel MCS is not "medium", the process proceeds to step S46. That is, in this case, it is determined that the current multi-level MCS is "small" and that the communication power may be increased as the radio wave condition of the communication path is deteriorated. There is a large restriction on the coding bit rate when coding moving image data, and it is decided to use the limited band b0 '(see FIG. 4).

After the process of step S43, S45, or S46, the process proceeds to step S47, and the control device 26 sets a target encoding bit rate when encoding moving image data in the compression rate control information. For example, when the process of step S43 is performed, the control device 26 sets the designated band b0 to the compression rate control information, and when the process of step S45 is performed, the middle restricted band is compressed. The rate control information is set, and when the process of step S14 is performed, the limited bandwidth b0 'is set as the compression rate control information.

In step S48, the control device 26 supplies, to the image compression device 23, the compression rate control information in which the target encoding bit rate is set in step S47. As a result, the control device 26 can control the image compression device 23 to encode moving image data at a target encoding bit rate, and then the process is ended.

Note that the control device 26 reduces the frame rate as described with reference to the flowchart of FIG. 6 based on MCS, or reduces the image size as described with reference to the flowchart of FIG. Thus, the consumption of communication power may be suppressed.

<Reduction of communication power based on communication power information>
By the way, in addition to suppressing communication power based on SIR and MCS as described above, for example, when communication power information can be obtained from the wireless transmission device 24, based on the communication power itself, It is possible to suppress the consumption of communication power.

A process example for suppressing the consumption of communication power based on the communication power information will be described with reference to the flowchart of FIG.

For example, the control device 26 supplies imaging control information for instructing the imaging device 21 to start capturing a moving image, and processing is performed periodically when moving image data is output from the imaging device 21. In step S51, the control device 26 acquires communication power from the communication power information supplied from the wireless transmission device 24.

In step S52, the control device 26 determines that the communication power consumed to perform communication in the current radio wave condition of the communication path is a predetermined communication power determination reference value (for example, larger than the minimum power p0) set in advance. It is determined whether or not the power in the vicinity of the minimum power p0).

If it is determined in step S52 that the current communication power is larger than the communication power determination reference value, the process proceeds to step S53. That is, in this case, it is determined that the communication power may be increased as the radio wave condition of the communication channel is deteriorated. Therefore, the control device 26 is configured to encode the moving image data. , And decide to use the limited band b0 '(see FIG. 4).

On the other hand, if it is determined in step S52 that the current communication power is not (greater than or less than) the communication power determination reference value, the process proceeds to step S54. That is, in this case, it is determined that the radio wave condition of the communication path is good and there is no possibility that the communication power may increase. Therefore, the control device 26 limits the encoding bit rate when encoding moving image data. It is decided to use the designated band b0 (see FIG. 4) without performing it.

After the process of step S53 or S54, the process proceeds to step S55, where the control device 26 sets the target encoding bit rate when encoding moving image data in the compression rate control information. For example, when the process of step S53 is performed, the control device 26 sets the limited band b0 'to the compression rate control information, and when the process of step S54 is performed, the control rate of the designated band b0 is compressed. Set in control information.

In step S56, the control device 26 supplies, to the image compression device 23, the compression rate control information in which the target encoding bit rate is set in step S55. As a result, the control device 26 can control the image compression device 23 to encode moving image data at a target encoding bit rate, and then the process is ended.

As described above, the control device 26 can avoid an increase in communication power before the communication bandwidth decreases, and as a result, can suppress the communication power based on the communication power information.

<Configuration Example of Moving Image Reproduction Communication Terminal>
FIG. 12 is a block diagram showing a configuration example of an embodiment of a moving image reproduction communication terminal to which the present technology is applied.

The moving image reproduction communication terminal 31 shown in FIG. 1 has a function of receiving moving image data by wireless communication and reproducing the moving image, and the wireless antenna 41, the wireless transmission device 42, the image decoding device 43, and the image processing A device 44, a display device 45, and a control device 46 are provided. For example, the moving image reproduction communication terminal 31 is a so-called smartphone or a tablet terminal.

The wireless antenna 41 receives a signal emitted to the space as an electromagnetic wave from a wireless base station (not shown), for example, a stream signal of moving image data.

The wireless transmission device 42 demodulates a stream signal of moving image data received via the wireless antenna 41, and supplies a bit stream of moving image data obtained thereby to the image decoding device 43. Further, the wireless transmission device 42 can acquire communication band information and communication parameters as in the case of the wireless transmission device 24 of FIG. 1 and supplies the communication band information and communication parameters to the control device 46. Furthermore, the wireless transmission device 42 can request the moving image distribution server to limit the quality (such as bit rate) of the moving image data requested to be distributed, under the control of the control device 46 as described later.

The image decoding device 43 decodes the bit stream of moving image data supplied from the wireless transmission device 42 in accordance with the decoding control signal supplied from the control device 46, and supplies the decoded moving image data to the image processing device 44.

The image processing device 44 subjects the moving image data supplied from the image decoding device 43 to various image processing in accordance with the image processing control signal supplied from the control device 46 and supplies the processed image data to the display device 45. For example, the image processing apparatus 44 can perform image processing for converting a frame rate, image processing for enlarging or reducing a screen size, color correction, and the like.

The display device 45 is configured of a display device such as a liquid crystal display (LCD) panel or an organic electro luminescence (EL) panel, and is supplied from the image processing device 44 in accordance with display control information supplied from the control device 46. Display a moving image according to the moving image data.

The control device 46 acquires communication parameters (SIR, MCS, or communication power information) from the radio transmission device 24 in the same manner as the control device 26 of FIG. Limit the quality of video data that requires delivery before it degrades. Thereby, the control device 46 can suppress the communication power.

Also in the moving picture reproduction communication terminal 31 configured in this way, as in the case of the moving picture imaging communication terminal 11 in FIG. 1, as described above with reference to FIG. Have a changing relationship. Therefore, in the moving image reproduction communication terminal 31, the control device 46 can optimize the consumption of communication power as a whole by performing the same communication control as the control device 26 of FIG.

FIG. 13 is a block diagram showing an example of the configuration of a moving image distribution system.

A plurality of moving image reproduction communication terminals 31 (three moving image reproduction communication terminals 31-1 to 31-3 in the example of FIG. 13) are connected to the moving image distribution system 51 shown in FIG. The moving image distribution system 51 is configured such that the wireless communication base station 61 performing wireless communication with the moving image reproduction communication terminal 31 is connected to the moving image distribution server 62 via the network 63 including the Internet network and the like. Be done.

The wireless communication base station 61 can wirelessly communicate with the moving image reproduction communication terminal 31 and transmits moving image data distributed from the moving image distribution server 62 to the moving image reproduction communication terminal 31 via the network 63. .

The moving image distribution server 62 prepares a plurality of different bit rate files for the same content. In the example shown in FIG. 13, a file 63-1 of 2.4 Mbps, a file 63-2 of 1.2 Mbps, a file 63-3 of 500 kbps, a file 63-4 of 300 kbps, and a file 63-5 of 128 kbps are prepared.

Then, when a request is made to the moving image distribution server 62 so as to download a file of a bit rate matched to the communicable bandwidth of each of the moving image reproduction communication terminals 31-1 to 31-3, the moving image The image delivery server 62 transfers the requested bit rate file via the network 63 and via the wireless communication base station 61.

<Reduction of communication power based on SIR>
A process example of suppressing the consumption of communication power based on the SIR will be described with reference to the flowchart of FIG.

For example, when the control device 46 requests a moving image via the wireless transmission device 42 and distribution of moving image data from the moving image distribution server 62 is started, processing is performed periodically. In step S61, the control device 26 acquires the SIR from the communication parameters supplied from the wireless transmission device 42.

In step S62, the control device 46 determines whether the SIR according to the current radio wave condition of the communication path is larger than the SIR determination reference value. Here, as the SIR determination reference value, the SIR value s0 described with reference to FIG. 4 may be used, or an SIR value (SIR value s1) set from the outside in advance for the video reproduction communication terminal 31. Larger values and SIR values less than or equal to s 0) may be used.

If it is determined in step S62 that the current SIR is larger than the SIR determination reference value, the process proceeds to step S63. That is, in this case, it is determined that the radio wave condition of the communication path is good and there is no possibility that the communication power is increased. Therefore, the control device 46 sets the bit rate of moving image data requested to the moving image distribution server 62 to the maximum bit rate within the communicable band (or is set as a default to the moving image reproduction communication terminal 31) Choose to use the

On the other hand, when it is determined in step S62 that the current SIR is not larger than (is equal to or less than) the SIR determination reference value, the process proceeds to step S64. That is, in this case, it is determined that the communication power may be increased as the radio wave condition of the communication path is deteriorated. Therefore, the control device 46 sets the bit rate of the moving image data requested to the moving image distribution server 62 to a larger bit rate (ie, at the current time) from bit rates smaller than the current bit rate. Choose to use the next higher bit rate).

After the process of step S63 or S64, the process proceeds to step S65, and the control device 46 selects the bit rate selected in each step as the bit rate of the moving picture data requested to the moving picture distribution server 62 The request command to be sent to the distribution server 62 is set.

In step S66, the control device 46 supplies the request command for which the bit rate has been set in step S65 to the wireless transmission device 42, and causes the wireless communication base station 61 to transmit the request command by wireless communication. As a result, the moving image distribution server 62 can distribute moving image data of the bit rate set in the request command, and then the process is terminated.

As described above, the moving image reproduction communication terminal 31 can avoid an increase in communication power by requesting moving image data with a lower bit rate before the communication bandwidth decreases, and as a result, the communication power can be reduced. It can control.

<Reduction of communication power based on communication power information>
A process example of suppressing the consumption of communication power based on the communication power information will be described with reference to the flowchart of FIG.

For example, when the control device 46 requests a moving image via the wireless transmission device 42 and distribution of moving image data from the moving image distribution server 62 is started, processing is performed periodically. In step S71, the control device 26 obtains communication power from the communication power information supplied from the wireless transmission device 24.

In step S72, control device 46 determines whether or not the communication power consumed to perform communication in the current radio wave condition of the communication path is larger than a predetermined communication power determination reference value set in advance. .

If it is determined in step S72 that the current communication power is larger than the communication power determination reference value, the process proceeds to step S73. That is, in this case, it is determined that the communication power may be increased as the radio wave condition of the communication path is deteriorated. Therefore, the control device 46 sets the bit rate of the moving image data requested to the moving image distribution server 62 to a larger bit rate (ie, at the current time) from bit rates smaller than the current bit rate. Choose to use the next higher bit rate).

On the other hand, when it is determined in step S72 that the current communication power is not larger than (is less than) the communication power determination reference value, the process proceeds to step S74. That is, in this case, it is determined that the radio wave condition of the communication path is good and there is no possibility that the communication power is increased. Therefore, the control device 46 sets the bit rate of moving image data requested to the moving image distribution server 62 to the maximum bit rate within the communicable band (or is set as a default to the moving image reproduction communication terminal 31) Choose to use the

After the process of step S73 or S74, the process proceeds to step S75, and the control device 46 selects the bit rate selected in each step as the bit rate of the moving picture data requested to the moving picture distribution server 62 The request command to be sent to the distribution server 62 is set.

In step S76, the control device 46 supplies the request command for which the bit rate has been set in step S75 to the wireless transmission device 42, and causes the wireless communication base station 61 to transmit the request command by wireless communication. As a result, the moving image distribution server 62 can distribute moving image data of the bit rate set in the request command, and then the process is terminated.

<Example of computer configuration>
Note that the processes described with reference to the above-described flowchart do not necessarily have to be processed in chronological order according to the order described as the flowchart, and processes performed in parallel or individually (for example, parallel processes or objects Processing) is also included. The program may be processed by a single CPU or may be distributed and processed by a plurality of CPUs.

Further, the series of processes (the communication control method) described above can be performed by hardware or software. When a series of processes are executed by software, the various functions are executed by installing a computer in which a program constituting the software is incorporated in dedicated hardware or various programs. The program can be installed, for example, on a general-purpose personal computer from a program recording medium on which the program is recorded.

FIG. 16 is a block diagram showing an example of a hardware configuration of a computer that executes the series of processes described above according to a program.

In the computer, a central processing unit (CPU) 101, a read only memory (ROM) 102, a random access memory (RAM) 103, and an electronically erasable and programmable read only memory (EEPROM) 104 are mutually connected by a bus 105. . Further, an input / output interface 106 is connected to the bus 105, and the input / output interface 106 is connected to the outside.

In the computer configured as described above, the CPU 101 loads a program stored in, for example, the ROM 102 and the EEPROM 104 into the RAM 103 via the bus 105 and executes the program, whereby the series of processes described above are performed. Further, the program executed by the computer (CPU 101) can be previously installed in the ROM 102, or can be externally installed or updated in the EEPROM 104 through the input / output interface 106.

<Example of combination of configurations>
Note that the present technology can also have the following configurations.
(1)
A parameter acquisition unit for acquiring a parameter correlated with at least one of a communication state and communication power from a wireless transmission apparatus that transmits and receives moving image data by performing wireless communication;
A communication control apparatus, comprising: a restriction unit that restricts the quality of the moving image data before the communicable band is reduced according to the parameters and the radio wave condition of the communication path is deteriorated.
(2)
The parameter is a signal to interference ratio (SIR) indicating a ratio of interference power to signal power in a channel used in the wireless communication,
The communication control apparatus according to (1), wherein the limiting unit limits the quality of the moving image data when the SIR becomes smaller than a predetermined SIR determination reference value.
(3)
The parameter is a modulation and coding set (MCS) indicating a modulation scheme in a channel used in the wireless communication,
The communication control apparatus according to (1) or (2), wherein the restriction unit imposes a restriction so as to lower the quality of the moving image data in response to a decrease in the multilevel level of the MCS.
(4)
The parameter is communication power information indicating communication power consumed by the wireless transmission device to perform wireless communication,
The restriction unit provides restriction so as to reduce the quality of the moving image data when the current communication power becomes larger than a predetermined communication power judgment reference value. (1) to (3) The communication control device according to any one of the above.
(5)
The image processing apparatus further includes an image compression unit that compresses the moving image data acquired by capturing a moving image by the imaging device and supplies the compressed data to the wireless transmission device.
The communication control apparatus according to any one of (1) to (4), wherein the restriction unit restricts the compression rate of the moving image data by the image compression unit.
(6)
The image processing apparatus further includes an image processing unit that performs image processing on the moving image data and supplies the processed image data to the image compression unit.
The communication control apparatus according to (5), wherein the image compression unit compresses the moving image data subjected to the image processing by the image processing unit.
(7)
The communication control apparatus according to (6), wherein the restriction unit reduces the frame rate of the moving image data by image processing by the image processing unit.
(8)
The communication control apparatus according to (6), wherein the restriction unit reduces the image size of the moving image data by image processing by the image processing unit.
(9)
The restriction unit transmits a request command to a moving image distribution server that distributes the moving image data to reproduce and display the moving image via the wireless transmission device, the moving image requesting the distribution The communication control device according to any one of (1) to (8) above, which limits the quality of data.
(10)
The parameter is a signal to interference ratio (SIR) indicating a ratio of interference power to signal power in a channel used in the wireless communication,
The communication control apparatus according to (9), wherein the limiting unit requests delivery of the moving image data having a bit rate lower than the current time when the SIR becomes smaller than a predetermined SIR determination reference value.
(11)
The parameter is communication power information indicating communication power consumed by the wireless transmission device to perform wireless communication,
The communication unit according to (9), wherein the restriction unit requests distribution of the moving image data having a bit rate lower than the current time when the current communication power becomes larger than a predetermined communication power judgment reference value. Control device.
(12)
A communication control device that controls wireless communication
Obtaining a parameter correlated with at least one of communication state and communication power from a wireless transmission device that transmits and receives moving image data by performing wireless communication;
And limiting the quality of the moving image data before the communicable band decreases with the deterioration of the radio wave condition of the communication path according to the parameter.
(13)
A computer of a communication control unit that controls wireless communication;
Obtaining a parameter correlated with at least one of communication state and communication power from a wireless transmission device that transmits and receives moving image data by performing wireless communication;
A program for executing processing including: limiting the quality of the moving image data before the communicable band decreases according to the deterioration of the radio wave condition of the communication path according to the parameter.
(14)
An imaging device for acquiring moving image data by capturing a moving image;
A wireless transmission device that performs transmission by wireless communication and transmits the moving image data;
A parameter having a correlation with at least one of the communication state and the communication power is acquired from the wireless transmission device, and the moving image data is acquired before the communicable band decreases according to the parameter according to the deterioration of the radio wave condition of the communication path. And a control unit that limits quality.
(15)
A display device for reproducing and displaying a moving image,
A wireless transmission device that performs transmission by wireless communication and receives moving image data;
A parameter having a correlation with at least one of the communication state and the communication power is acquired from the wireless transmission device, and the moving image data is acquired before the communicable band decreases according to the parameter according to the deterioration of the radio wave condition of the communication path. Control unit to limit the quality,
The control unit, when transmitting a request command to a moving image distribution server for distributing the moving image data to reproduce and display a moving image, via the wireless transmission device, the control unit requests the distribution A video communication terminal that limits the quality of data.

The present embodiment is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present disclosure. Further, the effects described in the present specification are merely examples and are not limited, and other effects may be present.

11 moving image imaging communication terminal, 21 imaging device, 22 image processing device, 23 image compression device, 24 wireless transmission device, 25 wireless antenna, 26 control device, 31 moving image reproduction communication terminal, 41 wireless antenna, 42 wireless transmission device, 43 image decoding device, 44 image processing device, 45 display device, 46 control device, 51 moving image delivery system, 61 wireless communication base station, 62 moving image delivery server, 63 network

Claims

A parameter acquisition unit for acquiring a parameter correlated with at least one of a communication state and communication power from a wireless transmission apparatus that transmits and receives moving image data by performing wireless communication;
A communication control apparatus, comprising: a restriction unit that restricts the quality of the moving image data before the communicable band is reduced according to the parameters and the radio wave condition of the communication path is deteriorated.
The parameter is a signal to interference ratio (SIR) indicating a ratio of interference power to signal power in a channel used in the wireless communication,
The communication control apparatus according to claim 1, wherein the limiting unit limits the quality of the moving image data to be degraded when the SIR becomes smaller than a predetermined SIR determination reference value.
The parameter is a modulation and coding set (MCS) indicating a modulation scheme in a channel used in the wireless communication,
The communication control apparatus according to claim 1, wherein the restriction unit restricts the quality of the moving image data to be reduced according to the decrease in the multi-level level of the MCS.
The parameter is communication power information indicating communication power consumed by the wireless transmission device to perform wireless communication,
The communication control device according to claim 1, wherein the limiting unit limits the quality of the moving image data when the current communication power becomes larger than a predetermined communication power determination reference value. .
The image processing apparatus further includes an image compression unit that compresses the moving image data acquired by capturing a moving image by the imaging device and supplies the compressed data to the wireless transmission device.
The communication control apparatus according to claim 1, wherein the restriction unit imposes a restriction on a compression rate of the moving image data by the image compression unit.
The image processing apparatus further includes an image processing unit that performs image processing on the moving image data and supplies the processed image data to the image compression unit.
The communication control device according to claim 5, wherein the image compression unit compresses the moving image data subjected to the image processing by the image processing unit.
The communication control device according to claim 6, wherein the restriction unit decreases a frame rate of the moving image data by image processing by the image processing unit.
The communication control device according to claim 6, wherein the restriction unit reduces the image size of the moving image data by image processing by the image processing unit.
The restriction unit transmits a request command to a moving image distribution server that distributes the moving image data to reproduce and display the moving image via the wireless transmission device, the moving image requesting the distribution The communication control device according to claim 1, which limits the quality of data.
The parameter is a signal to interference ratio (SIR) indicating a ratio of interference power to signal power in a channel used in the wireless communication,
10. The communication control apparatus according to claim 9, wherein the limiting unit requests delivery of the moving image data having a bit rate lower than a current time when the SIR becomes smaller than a predetermined SIR determination reference value.
The parameter is communication power information indicating communication power consumed by the wireless transmission device to perform wireless communication,
10. The communication control according to claim 9, wherein, when the current communication power becomes larger than a predetermined communication power judgment reference value, the restriction unit requests distribution of the moving image data having a bit rate lower than the current time. apparatus.
A communication control device that controls wireless communication
Obtaining a parameter correlated with at least one of communication state and communication power from a wireless transmission device that transmits and receives moving image data by performing wireless communication;
And limiting the quality of the moving image data before the communicable band decreases with the deterioration of the radio wave condition of the communication path according to the parameter.
A computer of a communication control unit that controls wireless communication;
Obtaining a parameter correlated with at least one of communication state and communication power from a wireless transmission device that transmits and receives moving image data by performing wireless communication;
A program for executing processing including: limiting the quality of the moving image data before the communicable band decreases according to the deterioration of the radio wave condition of the communication path according to the parameter.
An imaging device for acquiring moving image data by capturing a moving image;
A wireless transmission device that performs transmission by wireless communication and transmits the moving image data;
A parameter having a correlation with at least one of the communication state and the communication power is acquired from the wireless transmission device, and the moving image data is acquired before the communicable band decreases according to the parameter according to the deterioration of the radio wave condition of the communication path. And a control unit that limits quality.
A display device for reproducing and displaying a moving image,
A wireless transmission device that performs transmission by wireless communication and receives moving image data;
A parameter having a correlation with at least one of the communication state and the communication power is acquired from the wireless transmission device, and the moving image data is acquired before the communicable band decreases according to the parameter according to the deterioration of the radio wave condition of the communication path. Control unit to limit the quality,
The control unit, when transmitting a request command to a moving image distribution server for distributing the moving image data to reproduce and display a moving image, via the wireless transmission device, the control unit requests the distribution A video communication terminal that limits the quality of data.