Delay time management system

Abstract

To provide a delay time management system suitable for grasping a more accurate delay time when image data is transmitted from an image transmitting device to an image receiving device via a network.SOLUTION: In a delay time management system, first and second image transmitting / receiving devices and a delay time management server that stores a delay time between the first and second image transmitting / receiving devices perform bidirectional communication via a network. The first image transmitting / receiving device measures a first time when an imaging element of a camera provided in the first image transmitting / receiving device generated pixel data for a first reference pixel, which is a pixel at a specific position in a specific row within a frame, and transmits the pixel data of the first reference pixel to the second image transmitting / receiving device. The second image transmitting / receiving device measures a second time when a display device provided in the second image transmitting / receiving device displayed the pixel data for the first reference pixel. The delay time management server stores a first delay time based on the first time and the second time.SELECTED DRAWING: Figure 8

Description

[Technical field]

[0001] The present invention relates to a delay time management system. [Background technology]

[0002] An image receiving device receives images via a network from an image transmitting device located at at least one site. The image data is transmitted to the image receiving device, and the image transmitted from the image transmitting device is set in the image receiving device. In this case, the fifth generation mobile communication system (5G) With the practical application of this technology, image data can be transmitted with low latency, making it possible to transmit image data with low latency. The delay due to this is negligible. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-88305 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the delay due to the internal processing in the image transmitting device and the image receiving device is ignored. In addition, image transmission devices are installed at multiple locations, and multiple image transmissions are When transmitting image data from a plurality of image transmitting devices to an image receiving device, The timing of the image displayed on the display device varies due to the processing delay. The image transmission device transmits the image over a network. The internal structure of the image transmitting device and the image receiving device when transmitting image data to the image receiving device It is necessary to understand the delay time, including delays due to sub-processing.

[0005] The present invention provides a delay time management system suitable for grasping a more accurate delay time when transmitting image data from an image transmission device to an image reception device via a network. To achieve this purpose.

Means for Solving the Problems

[0006] In the present invention, a first and a second image transmission / reception device are connected via a network so as to communicate with each other bidirectionally. The first image transmission / reception device measures a first time when pixel data of a first reference pixel, which is a pixel at a specific position in a specific row within a frame of an imaging element of a camera included in the first image transmission / reception device, is generated, and sends the pixel data of the first reference pixel to the second transmission / reception device. The second image transmission / reception device measures a second time when a display device included in the second image transmission / reception device displays the pixel data of the first reference pixel. The delay time management server provides a delay time management system that stores a first delay time based on the first time and the second time.

Effects of the Invention

[0007] According to the delay time management system of the present invention, it is possible to grasp a more accurate delay time when transmitting image data from an image transmission device to an image reception device via a network.

Brief Description of the Drawings

[0008]

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Best Mode for Carrying Out the Invention

[0009] Hereinafter, an image transmission device, an image reception device, a delay time measurement device, a delay time management server, and a timing adjustment method according to one or more embodiments will be described with reference to the accompanying drawings.

[0010] First, with reference to FIG. 1, an image transmission system that transmits image data from a plurality of image transmission devices to an image reception device via a network will be conceptually described. The image data is moving image data. Note that the image transmission system may transmit audio data in addition to the image data. The processing of transmission and reception of audio data will be omitted from the illustration.

[0011] In FIG. 1, image transmission devices 10A to 10C are arranged at three different locations. An image reception device 20 is arranged at a location different from the locations where the image transmission devices 10A to 10C are arranged. The image transmission devices 10A to 10C include a camera 11 that captures a subject and a transmission unit 12 that transmits the image data generated by the camera 11 capturing the subject.

[0012] The image data transmitted from the image transmission devices 10A to 10C is transmitted to the image reception device 20 via the network 30. The network 30 is typically the Internet. The image reception device 20 includes a reception unit 21 that receives the image data and a display device 22 that displays a moving image based on the image data. The display device 22 may simultaneously display the moving images from the image transmission devices 10A to 10C, or may display the moving images from the image transmission devices 10A to 10C in sequence. It may be possible to display while switching images. Any image transmission device that does not specify any of the image transmission devices 10A to 10C is referred to as the image transmission device 10. One of them is not specified as the image transmission device 10.

[0013] <Specific configuration examples of the image transmission device, image reception device, and delay time measurement device> FIG. 2 shows a configuration example of the image transmission device 10 and the image reception device 20 configured to measure the delay time from the time when the camera 11 in the image transmission device 10 starts shooting a moving image to the time when the display device 22 in the image reception device 20 starts displaying the moving image. The image transmission device 10 and the image reception device 20 shown in FIG. 2 are provided with a configuration suitable for grasping the delay time including the delay due to their internal processing. The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments. As shown in FIG. 2, the image transmission device 10 includes, in addition to the camera 11, a GNSS satellite radio wave clock 13, a clock generation unit 14, an image memory 15, and a communication unit 16. The camera 11 has a control unit 111, an imaging element 112, and an image processing circuit 113. The image memory 15 includes a write / read control unit 150. The communication unit 16 functions as the transmission unit 12 in FIG. 1. The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments.

[0014] The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments. The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments. The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments. The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments. The delay time measurement unit 28 provided in the image reception device 20 constitutes the delay time measurement device of one or more embodiments, and measures a more accurate delay time including the delay due to the internal processing in the image transmission device 10 and the image reception device 20 as described below. The image transmission device 10 is the image transmission device of one or more embodiments. The image reception device 20 is the image reception device of one or more embodiments.

[0015] As shown in FIG. 2, in addition to the camera 11, the image transmission device 10 includes a GNSS satellite radio wave clock 13, a clock generation unit 14, an image memory 15, and a communication unit 16. The camera 11 has a control unit 111, an imaging element 112, and an image processing circuit 113. The image memory 15 includes a write / read control unit 150. The communication unit 16 functions as the transmission unit 12 in FIG. 1. As shown in FIG. 2, in addition to the camera 11, the image transmission device 10 includes a GNSS satellite radio wave clock 13, a clock generation unit 14, an image memory 15, and a communication unit 16. The camera 11 has a control unit 111, an imaging element 112, and an image processing circuit 113. The image memory 15 includes a write / read control unit 150. The communication unit 16 functions as the transmission unit 12 in FIG. 1. As shown in FIG. 2, in addition to the camera 11, the image transmission device 10 includes a GNSS satellite radio wave clock 13, a clock generation unit 14, an image memory 15, and a communication unit 16. The camera 11 has a control unit 111, an imaging element 112, and an image processing circuit 113. The image memory 15 includes a write / read control unit 150. The communication unit 16 functions as the transmission unit 12 in FIG. 1. As shown in FIG. 2, in addition to the camera 11, the image transmission device 10 includes a GNSS satellite radio wave clock 13, a clock generation unit 14, an image memory 15, and a communication unit 16. The camera 11 has a control unit 111, an imaging element 112, and an image processing circuit 113. The image memory 15 includes a write / read control unit 150. The communication unit 16 functions as the transmission unit 12 in FIG. 1.

[0016] In addition to the display device 22, the image reception device 20 includes a GNSS satellite radio wave clock 23, a clock generation It includes a section 24, a communication section 25, an image processing circuit 26, an image memory 27, and a delay time measurement section 28. The display device 22 has a control section 221, a drive circuit 222, and a liquid crystal panel 223. The image me mory 27 includes a write / read control section 270. The communication section 25 functions as the receiving section 21 in FIG. 1 and.

[0017] The GNSS satellite radio clock 13 receives radio waves from a satellite 40 for a global navigation satellite system (Global Navigation Satellit e System: GNSS) and outputs a 1PPS signal which is a pulse at 1-second intervals shown in FIG. 3(a) and a 10 MHz clock (hereinafter, 10 MHz clock) shown in FIG. 3(b). GNSS is, for example, GPS (Global Positioning S ystem).

[0018] Based on the input 1PPS signal and 10 MHz clock, the clock generation section 14 generates a 148.5 MHz clock (hereinafter, 148.5 MHz clock) shown in FIG. 3(c) and supplies it to the camera 11, the image memory 15, and the communication section 16. For convenience of illustration, the 148.5 MHz clock shown in FIG. 3 (c) is shown with the period of one clock significantly lengthened. Note that in addition to 148.5 MHz, the clock generation section 14 may generate clocks of other frequencies for video synchronization such as 297 MHz, 74. 25 MHz, 27 MHz, etc.

[0019] The image transmission device 10 may be provided with a clock generation section that generates a clock including time information based on radio waves received from a satellite 40 for GNSS. Supply a 10 MHz clock to the camera 11, the image memory 15, and the communication section 16, and the camera 11, the image memory 15, and the communication section 16 are 1 ​​​​It may be operated at a 0 MHz clock. In this case, the GNSS satellite radio clock 13 serves as a clock generation unit that generates a clock including time information. The frequencies of the clocks supplied to the camera 11, the image memory 1 5, and the communication unit 16 are not limited.

[0020] Assume that the GNSS satellite radio clock 13 generates a pulse of the 1PPS signal shown in Fig. 3(a) at time 0:0 0:00 and the next pulse at time 0:00:01. The clock generation unit 14 outputs a 148.5 MHz clock including time information, such as clocks numbered 0 to 148.5×10 -6 - 1 based on time 0:00:00 and clocks numbered 0 to 148.5×10 -6 -1 based on time 0:00:01.

[0021] The control unit 111 of the camera 11 controls the electronic shutter in the image sensor 112, and the image sensor 112 images the subject. The control unit 111 may be a central processing unit provided in the camera 11. The image data generated when the image sensor 112 images the subject is subjected to various image processes by the image processing circuit 113 and supplied to the image memory 15. The various image processes in the image processing circuit 113 include at least one or more of defective pixel interpolation processing, black level processing, white

[0022] balance processing, demosaicing processing, shading correction processing, and compression encoding processing. The image processing in the image processing circuit 113 includes at least compression encoding processing. The control unit 111 causes the image sensor 112 to turn off the electronic shutter of a predetermined reference pixel to obtain pixel data and...

[0023] The clock number of the 148.5 MHz clock indicating the time t0 when it is generated is used as metadata and is controlled to be superimposed on the blanking period of the image data. The reference pixel may be the pixel at the first row and the first position in the frame. That is, the clock number included in the image data output by the camera 11 indicates the time when the camera 11 starts generating the image data of each frame. As shown in FIG. 3(c), assume that the clock number indicating the time t0 included in the image data output by the camera 11 is Cn0 which is the clock number 0 as an example. The write / read control unit 150 writes the image data into the image memory 15. At this time, the write / read control unit 150 superimposes the clock number of the 148.5 MHz clock indicating the time t1 when the pixel data of the reference pixel of each frame is written into the image memory 15 as metadata on the blanking period of the image data, and writes the image data in this state into the image memory 15. As shown in FIG. 3(c), assume that the clock number indicating the time t1 included in the image data written into the image memory 15 is Cn1. In the image data written into the image memory 15, the clock number Cn0 and the clock number Cn1 are superimposed. The write / read control unit 150 reads out the image data stored in the image memory 15 and supplies it to the communication unit 16. The communication unit 16 packetizes the image data read from the image memory 15 and transmits it to the image receiving device 20 via the network 30. At this time, the communication unit 16 superimposes the clock number of the 148.5 MHz clock indicating the time t2 when the pixel data of the reference pixel of each frame is transmitted as metadata on the blanking period of the image data.

[0024] The write / read control unit 150 writes the image data into the image memory 15. At this time, when writing the pixel data of the reference pixel of each frame into the image memory 15, the write / read control unit 150 superimposes the clock number of the 148.5 MHz clock indicating the time t1 as metadata on the blanking period of the image data, and writes the image data in this state into the image memory 15. As shown in FIG. 3(c), assume that the clock number indicating the time t1 included in the image data written into the image memory 15 is Cn1. In the image data written into the image memory 15, the clock number indicating the time t1 is superimposed on the blanking period of the image data as metadata, and writes the image data in this state into the image memory 15. As shown in FIG. 3(c), assume that the clock number indicating the time t1 included in the image data written into the image memory 15 is Cn1. In the image data written into the image memory 15, the clock number Cn0 and the clock number Cn1 are superimposed. As shown in FIG. 3(c), assume that the clock number indicating the time t1 included in the image data written into the image memory 15 is Cn1. In the image data written into the image memory 15, the clock number indicating the time t1 is Cn1. In the image data written into the image memory 15, the clock number Cn0 and the clock number Cn1 are superimposed.

[0025] The write / read control unit 150 reads out the image data stored in the image memory 15 and supplies it to the communication unit 16. The communication unit 16 packetizes the image data read from the image memory 15 and transmits it to the image receiving device 20 via the network 30. At this time, the communication unit 16 superimposes the clock number of the 148.5 MHz clock indicating the time t2 when the pixel data of the reference pixel of each frame is transmitted as metadata on the blanking period of the image data, and transmits the image data in this state. The clock number of the 148.5 MHz clock indicating the time t2 when the pixel data of the reference pixel of each frame is transmitted is superimposed on the blanking period of the image data as metadata. ​In this state, the image data is packetized. As shown in (c) of FIG. 3, the pixel data of the reference pixel Let the clock number indicating the time t2 to transmit the data be Cn2. As a result, the clock number Cn2 indicates the time t2 when the pixel data of the reference pixel was transmitted.

[0026] Also, the communication unit 16 adds clock frequency information to the image data and packetizes it in order to transmit to the image receiving device 20 that the camera 11, the image memory 15, and the communication unit 16 are operating at 148.5 MHz clock. The packet data transmitted from the image transmitting device 10 to the image receiving device 20 via the network 30 includes the image data and the clock frequency information, and the clock numbers Cn0, Cn1, and Cn2 are superimposed on the image data.

[0027] The GNSS satellite radio wave clock 23 in the image receiving device 20 also receives the radio wave from the satellite 40 in the same way as the GNSS satellite radio wave clock 13 and outputs the 1 PPS signal which is a pulse at 1 - second intervals shown in FIG. 4(a) and the 10 MHz clock shown in FIG. 4(b).

[0028] In FIG. 2, the satellite 40 that transmits the radio waves received by the GNSS satellite radio wave clock 13 and the GNSS satellite radio wave clock 23 is the same common satellite 40. The satellite 40 that transmits the radio wave received by the GNSS satellite radio wave clock 13 and the satellite 40 that transmits the radio wave received by the GNSS satellite radio wave clock 23 may be different. The GNSS satellite radio wave clocks 13 and 23 may receive the radio wave from any of the plurality of satellites 40 operated by a single global navigation satellite system.

[0029] The communication unit 25 receives the packet data including the image data and the clock frequency information, ​​​​​​​​​​​Supply the clock frequency information to the clock generation unit 24 and supply the image data to the image processing circuit 26. Since the clock generation unit 24 has received the clock frequency information indicating 148.5 MHz, based on the input 1PPS signal and 10 MHz clock, it generates the 148.5 MHz clock shown in Fig. 4(c). The 148.5 MHz clock is supplied to the display device 22, communication unit 25, image memory 27, and delay time measurement unit 28.

[0030] The 148.5 MHz clock shown in Fig. 4(c) is the same clock (same phase and same frequency) as the 148.5 MHz clock shown in Fig. 3(c).

[0031] The clock that the clock generation unit 24 supplies to the display device 22, communication unit 25, image memory 27, and delay time measurement unit 28 is, as described above, a 148.5 MHz clock including time information.

[0032] As shown in Fig. 4(c), the communication unit 25 superimposes, as metadata, the clock number of the 148.5 MHz clock indicating the time t3 when the pixel data of the reference pixels of each frame is received from the network 30 during the blanking period of the image data. Assume that the clock number indicating the time t3 when the pixel data of the reference pixels is received is Cn3. Therefore, the clock numbers Cn0, Cn1, Cn2, and Cn3 are superimposed on the image data output from the communication unit 25.

[0033] The image data output from the communication unit 25 is subjected to various image processes by the image processing circuit 26 and then supplied to the image memory 27. The image process in the image memory 27 is at least decompression and decoding. The image processing circuit 26 uses the clock number C included in the image data.​​​​​​ n0, Cn1, Cn2, and Cn3 are supplied to the delay time measurement unit 28.

[0034] The write / read control unit 270 writes the image data supplied to the image memory 27 to the image memory 27. The image data stored in the image memory 27 is read out and the drive circuit of the display device 22 is At this time, the write / read control unit 270 supplies the image of the reference pixel of each frame to the line 222. The clock number of the 148.5MHz clock indicating the time t4 when the raw data was read is At time t4, the pixel data of the reference pixel is supplied to the drive circuit 222. As shown in FIG. 4(c), image data is read out from the image memory 27. The clock number indicating the time t4 is assumed to be Cn4.

[0035] The control unit 221 of the display device 22 drives the liquid crystal panel The control unit 221 controls the drive circuit 222 so that the display device 22 displays the The control unit 221 may be a central processing unit that controls the pixel data of the reference pixel of each frame. The clock number of the 148.5 MHz clock indicating the time t5 displayed on the liquid crystal panel 223 is The pixel data of the reference pixel is supplied to the delay time measurement unit 28. As shown in FIG. It is assumed that the clock number indicating time t5 displayed on the liquid crystal panel 223 is Cn5.

[0036] It is not necessary for the display device 22 to operate at a 148.5 MHz clock. The 148.5MHz clock is supplied to the This is to supply the clock number Cn5 indicating 5 to the delay time measuring unit 28.

[0037] When the display device 22 is a projection type display device instead of a direct view type display device, the liquid crystal panel 223 is a liquid crystal display element for a projection type display device. The display device 22 may include a display panel (display element) other than the liquid crystal panel.

[0038] The delay time measurement unit 28 obtains the delay time between the image transmission device 10 and the image reception device 20 according to the processes shown in the flowcharts of FIGS. 5 to 7, and determines a delay time correction value for correcting the delay due to the delay time.

[0039] In FIG. 5, at step S1, the delay time measurement unit 28 sets the shooting time in the image transmission device 10, and at step S2, sets the display time in the image reception device 20. FIG. 6 shows the detailed process of step S1. In FIG. 6, at step S11, the delay time measurement unit 28 determines whether or not a clock number Cn0 (that is, time t0) exists. If the clock number Cn0 exists (YES), the delay time measurement unit 28 sets, at step S13, the time t0 indicated by the clock number Cn0 as the shooting time.

[0040] If the clock number does not exist at step S11 (NO), the delay time measurement unit 28 determines, at step S12, whether or not a clock number Cn1 (that is, time t1) exists. If the clock number Cn1 exists (YES), the delay time measurement unit 28 sets, at step S14, the time t1 indicated by the clock number Cn1 as the shooting time. If the clock number Cn1 does not exist (NO), the delay time measurement unit 28 sets, at step S15, the time t2 indicated by the clock number Cn2 as the shooting time.

[0041] FIG. 7 shows the detailed processing of step S2. In FIG. 7, the delay time measurement unit 28 determines whether there is a clock number Cn5 (i.e., time t5) at step S21. If there is a clock number Cn5 (YES), the delay time measurement unit 28 sets the time t5 as the display time at step S23.

[0042] If there is no clock number Cn5 at step S21 (NO), the delay time measurement unit 28 determines whether there is a clock number Cn4 (i.e., time t4) at step S22. If there is a clock number Cn4 (YES), the delay time measurement unit 28 sets the time t4 as the display time at step S24. If there is no clock number Cn4 (NO), the delay time measurement unit 28 sets the time t3 indicated by the clock number Cn3 as the display time at step S25.

[0043] In FIG. 6, the reason for determining whether there is a clock number Cn0 is that the clock number Cn0 indicating the time t0 when the camera 11 starts generating the image data of each frame may not be configured to be superimposed on the image data. Also, the reason for determining whether there is a clock number Cn1 is that the clock number Cn1 indicating the time t1 when the image memory 15 writes the image data may not be configured to be superimposed on the image data.

[0044] In FIG. 7, the reason for determining whether there is a clock number Cn5 is that the display device 22 may not be configured to supply the clock number Cn5 indicating the time t5 when the image data is displayed on the liquid crystal panel 223 to the delay time measurement unit 28. Also, the clock ​​​​​​​​​​​​The reason for determining whether or not the lock number Cn4 exists is that the image memory 27 may not be configured to supply the clock number Cn4 indicating the time t4 when the image data is read out to the delay time measurement unit 28. This is because it may not be configured to supply the clock number Cn4 indicating the time t4 when the image data is read out to the delay time measurement unit 28.

[0045] Returning to FIG. 5, in step S3, the delay time measurement unit 28 calculates the delay time between the image transmission device 10 and the image reception device 20, which is the difference between the shooting time and the display time. The delay time measurement unit 28 determines in step S4 whether or not the shooting time is time t2 and the display time is time t3. When the shooting time is time t2 and the display time is time t3, the time from time t2 to time t3 is the transmission time of the image data by the network 30. Therefore, it does not represent the delay time from when the image transmission device 10 starts generating the image data until the image reception device 20 starts displaying the image data. Therefore, if in step S4 the shooting time is time t2 and the display time is time t3 ( YES), the delay time measurement unit 28 determines in step S5 whether or not a previously measured fixed correction value is set in the delay time measurement unit 28. The fixed correction value is the time obtained by adding one or both of the average time from time t0 to time t2 and the average time from time t3 to time t5.

[0046] Therefore, if in step S4 the shooting time is time t2 and the display time is time t3 ( YES), the delay time measurement unit 28 determines in step S5 whether or not a previously measured fixed correction value is set in the delay time measurement unit 28. The fixed correction value is the time obtained by adding one or both of the average time from time t0 to time t2 and the average time from time t3 to time t5. One of them, or the time obtained by adding both of them.

[0047] If the previously measured fixed correction value is set in step S5 (YES), the time obtained by adding the fixed correction value to the delay time obtained in step S 3 is determined as the delay time correction value, and the process is terminated. The process is terminated.

[0048] In step S4, if the photographing time is not time t2 and the display time is not time t3 (NO), Or, if the fixed correction value measured in advance is not set in step S5 (NO), the delay In step S7, the time measurement unit 28 directly delays the delay time obtained in step S3. This is then determined as the delay time correction value, and the process is terminated.

[0049] As described above, the image transmission device 10 includes the camera 11, the clock generation unit 14, the image memory 1 The clock generating unit 14 receives a signal from a GNSS satellite 40. A first clock (for example, a 148.5 MHz clock) is generated that contains time information based on the The camera 11 operates according to a first clock, and the image sensor 112 captures an image of a subject. The image memory 15 is driven by the first clock. The image data is written and read under the control of the write / read control unit 150 .

[0050] The communication unit 16 reads out the image from the image memory 15 and outputs a small number of the first to third clock numbers. At least one of the superimposed image data is transmitted. The first to third clock numbers are the clocks. The numbers are Cn0 to Cn2.

[0051] The first clock number is the number of pixels in the frame that the camera 11 captures. The camera 11 superimposes the first clock number onto the image data. If the apparatus is configured to execute a process of: will be sent.

[0052] The second clock number is the number at which the write / read control unit 150 writes the pixel data of the reference pixel to the image memory. Indicates the time written to 15. If the write / read control unit 150 is configured to execute a process of superimposing the second clock number on the image data, the image data including the second clock number is transmitted. The third clock number indicates the time when the communication unit 16 transmits the pixel data of the reference pixel. If the communication unit 16 is configured to execute a process of superimposing the third clock number on the image data, the image data including the third clock number is transmitted. The third clock number indicates the time when the communication unit 16 transmits the pixel data of the reference pixel. If the communication unit 16 is configured to execute a process of superimposing the third clock number on the image data, the image data including the third clock number is transmitted. The image receiving device 20 includes a communication unit 25 that receives image data on which at least one of the first clock number, the second clock number, and the third clock number is superimposed. If the communication unit 25 is the first communication unit, the communication unit 16 is the second communication unit. If the communication unit 16 is the first communication unit, the communication unit 25 is the second communication unit.

[0053] The first clock number is the clock number in the first clock generated by the clock generation unit 14 (the first clock generation unit), and indicates the time when the imaging element 112 of the camera 11 generates the pixel data of the reference pixel in the frame. The second clock number is the clock number in the first clock, and indicates the time when the write / read control unit 150 (the first write / read control unit) writes the pixel data of the reference pixel to the image memory 15 (the first image memory). The third clock number is the clock number in the first clock, and indicates the time when the communication unit 16 (the second communication unit) transmits the pixel data of the reference pixel. The first clock number is the clock number in the first clock generated by the clock generation unit 14 (the first clock generation unit), and indicates the time when the imaging element 112 of the camera 11 generates the pixel data of the reference pixel in the frame. The second clock number is the clock number in the first clock, and indicates the time when the write / read control unit 150 (the first write / read control unit) writes the pixel data of the reference pixel to the image memory 15 (the first image memory). The third clock number is the clock number in the first clock, and indicates the time when the communication unit 16 (the second communication unit) transmits the pixel data of the reference pixel.

[0054] The first clock number is the clock number in the first clock generated by the clock generation unit 14 (the first clock generation unit), and indicates the time when the imaging element 112 of the camera 11 generates the pixel data of the reference pixel in the frame. The second clock number is the clock number in the first clock, and indicates the time when the write / read control unit 150 (the first write / read control unit) writes the pixel data of the reference pixel to the image memory 15 (the first image memory). The third clock number is the clock number in the first clock, and indicates the time when the communication unit 16 (the second communication unit) transmits the pixel data of the reference pixel. The second clock number is the clock number in the first clock, and indicates the time when the write / read control unit 150 (the first write / read control unit) writes the pixel data of the reference pixel to the image memory 15 (the first image memory). The third clock number is the clock number in the first clock, and indicates the time when the communication unit 16 (the second communication unit) transmits the pixel data of the reference pixel. The third clock number is the clock number in the first clock, and indicates the time when the communication unit 16 (the second communication unit) transmits the pixel data of the reference pixel. The image receiving device 20 further includes a clock generation unit 24 (the second clock generation unit), an image memory 27 (the second image memory), a display device 22, and a delay time measurement unit 28.

[0055] The image receiving device 20 further includes a clock generation unit 24 (the second clock generation unit), an image memory 27 (the second image memory), a display device 22, and a delay time measurement unit 28. The clock generation unit 24 (the second clock generation unit), the image memory 27 (the second image memory), the display device 22, and the delay time measurement unit 28. The forming unit 24 generates a second clock identical to the first clock. The image memory 27 operates according to the second clock and writes and reads out image data based on the control by the write / read control unit 270 (second write / read control unit). The display device 22 displays the image data read from the image memory 27. It operates according to the second clock and writes and reads out image data based on the control by the write / read control unit 270 (second write / read control unit). The display device 22 displays the image data read from the image memory 27.

[0056] The delay time measurement unit 28 measures the delay time indicating the difference between any one of the clock numbers of the first to third clock numbers and any one of the clock numbers of the fourth to sixth clock numbers. The fourth clock number is the clock number at the second clock and indicates the time when the communication unit 25 receives the pixel data of the reference pixel. The fifth clock number is the clock number at the second clock and indicates the time when the write / read control unit 270 reads out the pixel data of the reference pixel from the image memory 27. The sixth clock number is the clock number at the second clock and indicates the time when the display device 22 displays the pixel data of the reference pixel. It measures the delay time indicating the difference between any one of the clock numbers of the first to third clock numbers and any one of the clock numbers of the fourth to sixth clock numbers. The fourth clock number is the clock number at the second clock and indicates the time when the communication unit 25 receives the pixel data of the reference pixel. The fifth clock number is the clock number at the second clock and indicates the time when the write / read control unit 270 reads out the pixel data of the reference pixel from the image memory 27. The sixth clock number is the clock number at the second clock and indicates the time when the display device 22 displays the pixel data of the reference pixel.

[0057] When the delay time measurement unit 28 acquires the first clock number (clock number Cn0), it is preferable to measure the delay time using the first clock number. When the delay time measurement unit 28 cannot acquire the first clock number and acquires the second clock number (clock number Cn1), it is preferable to measure the delay time using the second clock number. When the delay time measurement unit 28 acquires the sixth clock number (clock number Cn5), it is preferable to measure the delay time using the sixth clock number. When the delay time measurement unit 28 cannot acquire the sixth clock number and acquires the fifth clock number (clock number Cn4), it is preferable to measure the delay time using the fifth clock number. When the delay time measurement unit 28 acquires the first clock number (clock number Cn0), it is preferable to measure the delay time using the first clock number. When the delay time measurement unit 28 cannot acquire the first clock number and acquires the second clock number (clock number Cn1), it is preferable to measure the delay time using the second clock number. When the delay time measurement unit 28 acquires the sixth clock number (clock number Cn5), it is preferable to measure the delay time using the sixth clock number. When the delay time measurement unit 28 cannot acquire the sixth clock number and acquires the fifth clock number (clock number Cn4), it is preferable to measure the delay time using the fifth clock number. ​​​​

[0058] The delay time measurement unit 28 is a delay time measurement device according to one or more embodiments. As described above, the delay time measurement unit 28 obtains the difference between any one of the first to third clock numbers and any one of the fourth to sixth clock numbers. Thereby, the delay time measurement unit 28 measures the delay time when the image receiving device 20 receives and displays the image data generated by the image transmitting device 10 and transmitted to the image receiving device 20. According to the image transmitting device, the image receiving device, and the delay time measurement device of one or more embodiments, it is possible to grasp a more accurate delay time when transmitting image data from the image transmitting device 10 to the image receiving device 20 via the network 30.

[0059] In the image transmitting device, the image receiving device, and the delay time measurement device of one or more embodiments, when transmitting image data from the image transmitting device 10 to the image receiving device 20 via the network 30, it is possible to grasp a more accurate delay time.

[0060] <Delay time management server> In FIG. 8, at bases B1 to B3, image transmission / reception devices 120A to 120C are respectively arranged. The image transmission / reception devices 120A to 120C communicate with each other bidirectionally via the network 30. An image transmission / reception device that does not specify any one of the image transmission / reception devices 120A to 120C is referred to as an image transmission / reception device 120. The image transmission / reception device 120 has the configurations of both the image transmission device 10 and the image receiving device 20 shown in FIG. 2. As shown in FIG. 8, schematically, the image transmission / reception device 120 includes a camera 11, a display device 22, a delay time measurement unit 28, a control unit 122, and a transmission / reception unit 121. Although not shown in FIG. 8, the image transmission / reception device 120 includes a GNSS satellite radio clock 13 (or 23) and a clock generation unit 14 (or 24), and the camera 11 and the display device 22 are provided with 148.5 both have the configurations of the image transmission device 10 and the image receiving device 20 shown in FIG. 2.

[0061] As shown in FIG. 8, schematically, the image transmission / reception device 120 includes a camera 11, a display device 22, a delay time measurement unit 28, a control unit 122, and a transmission / reception unit 121. Although not shown in FIG. 8, the image transmission / reception device 120 includes a GNSS satellite radio clock 13 (or 23) and a clock generation unit 14 (or 24), and the camera 11 and the display device 22 are provided with 148.5 lock generation unit 14 (or 24), and the camera 11 and the display device 22 are provided with 148.5 An MHz clock is supplied. The transmission / reception unit 121 corresponds to the communication units 16 and 25. The control unit 122 corresponds to the control units 111 and 221.

[0062] The image transmission device 10 shown in FIG. 2 describes in detail the configuration when the image transmission / reception device 120 shown in FIG. 8 operates as an image transmission device. The image reception device 20 shown in FIG. 2 describes in detail the configuration when the image transmission / reception device 120 shown in FIG. 8 operates as an image reception device. The network 30 is connected to a delay time management server 50. The delay time management ser ver 50 communicates bidirectionally with the image transmission / reception devices 120A to 120C. As shown in FIG. 9

[0063] the delay time management server 50 stores the delay time when the image transmission / reception devices 120A to 120C arranged at the bases B1 to B3 are on the transmission side and other image transmission / reception devices 120 are on the reception side. FIG. 9 also shows information indicating which of the times t0 to t2 the delay time is from and which of the times t 3 to t5 the delay time is up to for the delay time. The delay time management server 50 may update the delay time shown in FIG. 9 each time the delay time measurement unit 28 of the image transmission / reception devices 120A to 120C measures the delay time. The delay time management ser ver 50 may update the delay time shown in FIG. 9 to the latest delay time determined by the delay time measurement unit 28 each time a predetermined time elapses. The image transmission / reception device 120 can read the delay time stored in the delay time management ser ver 50. As described above, the delay time management server 50 which is one or more delay time management servers

[0064] The delay time management server 50 may update the delay time shown in FIG. 9 each time the delay time measurement unit 28 of the image transmission / reception devices 120A to 120C measures the delay time. The delay time management ser ver 50 may update the delay time shown in FIG. 9 to the latest delay time determined by the delay time measurement unit 28 each time a predetermined time elapses. The image transmission / reception device 120 can read the delay time stored in the delay time management ser ver 50. As described above, the delay time management server 50 which is one or more delay time management servers can read the delay time stored in the delay time management server 50.

[0065] As described above, the delay time management server 50, which is one or more delay time management servers is connected to the network 30. The network 30 includes at least two images The first and second image transmitting and receiving devices, which are the transmitting and receiving device 120, communicate with each other bidirectionally are connected. Any two of the image transmitting and receiving devices 120A to 120C are the first and second image transmitting and receiving devices.

[0066] The first image transmitting and receiving device measures the first delay time when the first image transmitting and receiving device receives and displays the image data generated by the second image transmitting and receiving device and transmitted to the first image transmitting and receiving device (delay time measuring unit 28). The second image transmitting and receiving device includes a second delay time measuring unit (delay time measuring unit 28) that measures the second delay time when the second image transmitting and receiving device receives and displays the image data generated by the first image transmitting and receiving device and transmitted to the second image transmitting and receiving device.

[0067] The delay time management server 50 stores the first delay time transmitted from the first image transmitting and receiving device via the network 30 and the second delay time transmitted from the second image transmitting and receiving device via the network 30.

[0068] According to the delay time management server 50 of one or more embodiments, when transmitting image data from the image transmitting and receiving device 120 operating as an image transmitting device to the image transmitting and receiving device 120 operating as an image receiving device via the network 30, a more accurate delay time can be managed.

[0069] <Timing Adjustment Method at the Time of Image Data Reception> As an example, in FIG. 10, musical instruments are played at each of the bases B1 to B3, and the supervisor of the performance ​​​​​​​​Consider the case where the image transmission / reception device 120B at the base B2 where it is located receives the image data transmitted from the image transmission / reception devices 120A and 120 C. The performance of a musical instrument is an example of a predetermined action performed by a person who is the subject. The subject performing the musical instrument is the performer.

[0070] The camera 11 of the image transmission / reception device 120A photographs the performer at the base B1, and the transmission / reception unit 121 transmits the image data to the image transmission / reception device 120B. The camera 11 of the image transmission / reception device 120C photographs the performer at the base B3, and the transmission / reception unit 121 transmits the image data to the image transmission / reception device 120B . The camera 11 of the image transmission / reception device 120B photographs the performer at the base B2, and the display device 22 displays the moving image. The display device 22 of the image transmission / reception device 120B may display the moving images generated by the image transmission / reception devices 120A~120C simultaneously, or may display the moving images generated by the image transmission / reception devices 120A~120C while switching them .

[0071] The image transmission / reception devices 120A~120C are each provided with a timing instruction unit 29 for giving a signal to start the performance to the performers located at the bases B1~B3. As shown in FIG. 11, the timing instruction unit 29 has a control unit 291, a clock 292, an operation unit 293, a delay time correction value holding unit 294, and a display unit 295. The clock 292 may be the GNSS satellite radio clock 13 (or 2 3). The display unit 295 may be a liquid crystal panel or an LED .

[0072] When the timing instruction unit 29 sets the time to start the performance to the control unit 291 by operating the operation unit 293, the control unit 291 monitors the time measured by the clock 292 and determines the time to start the performance ​​​​​It is configured to display a signal notifying the aiming on the display unit 295. For example, at 13: 00:00:00, assuming that the performance starts at each of the bases B1 to B3, the above-mentioned delay time exists until the image data is transmitted from the bases B1 and B3 to the base B2 and displayed on the display device 22. Therefore, the timings of all the performances of the bases B1 to B3 displayed at the base B2 do not match.

[0073] Therefore, based on the control by the control unit 122, the transmission / reception unit 121 reads the delay time shown in FIG. 9 from the delay time management server 50 and supplies it to the control unit 291 of the timing instruction unit 29. The control unit 291 causes the delay time correction value holding unit 294 to hold a delay time correction value based on the delay time. Here, the case where the delay time is used as the delay time correction value as it is is taken as an example.

[0074] In the example shown in FIG. 10, the delay time correction value holding unit 294 of the timing instruction unit 29 provided in the image transmission / reception device 120A holds a delay time of 10.3 ms with the base B1 as the transmission side and the base B2 as the reception side. The delay time correction value holding unit 294 of the timing instruction unit 29 provided in the image transmission / reception device 120C holds a delay time of 10.2 ms with the base B3 as the transmission side and the base B2 as the reception side.

[0075] There is no need for the delay time correction value holding unit 294 of the timing instruction unit 29 provided in the image transmission / reception device 120B to hold a delay time correction value. In FIG. 10, since the delay time is not supplied from the transmission / reception unit 121 to the timing instruction unit 29, the between the transmission / reception unit 121 and the timing instruction unit 29 is indicated by a dashed arrow line.

[0076] The control unit 291 of the timing instruction unit 29 provided in the image transmission / reception device 120A starts the performance​​​​​​​​​​​​​ Start the performance at a time 10.3 ms before 13:00:00 which is the time to start. Display a signal for notifying the timing on the display unit 295. The image transmission / reception apparatus 120C is provided with The control unit 291 of the timing instruction unit 29 is 13:00:00 which is the time to start the performance Display a signal for notifying the timing to start the performance at a time 10.2 ms before from on the display unit 295.

[0077] The control unit 291 of the timing instruction unit 29 provided in the image transmission / reception apparatus 120B starts the performance Display a signal for notifying the timing to start the performance at 13:00:00 which is the time to start on the display unit 295.

[0078] Each performer at bases B1 to B3 starts the performance in accordance with the signal displayed on the display unit 295 of the timing instruction unit 29 at each of bases B1 to B3. As a result, the image data displayed on the display device 22 at base B2 is displayed in a state where the timings of all the performances at bases B1 to B3 are matched.

[0079] Using the flowchart shown in FIG. 12, the processes executed by the image transmission / reception apparatuses 120A to 120C for adjusting the reception timing of the image data will be described. In FIG. 12, the control unit 122 of the image transmission / reception apparatus 120B sets the image transmission / reception apparatus 120B as the reference base at step S31. The control units 12 2 of the image transmission / reception apparatuses 120A and 120C which are the transmission-side bases acquire the corresponding delay time from the delay time management server 50 at step S32.

[0080] The control units 291 of the image transmission / reception apparatuses 120A and 120C perform the delay time ​​​​​Set the delay time as the delay time correction value in the interpolation correction value holding unit 294. Here, the delay time is directly used as the delay time correction value. The control units 291 of the image transmission / reception apparatuses 120A to 120C set the performance start time based on the operation input by the operation unit 293 in step S34.

[0081] The control units 122 of the image transmission / reception apparatuses 120A and 120C which are the transmission-side bases set, in step S351, the time that is earlier than the performance start time by the delay time correction value as the performance start timing. The control unit 122 of the image transmission / reception apparatus 120B which is the reference base sets, in step S352 the performance start time as the performance start timing.

[0082] The control units 122 of the image transmission / reception apparatuses 120A and 120C determine, in step S361, whether the current time has reached the performance start timing. If the current time has not reached the performance start timing (NO), the control unit 122 repeats the process of step S361. If the current time has reached the performance start timing (YES), the control unit 122 transfers the process to step S 371.

[0083] The control unit 122 of the image transmission / reception apparatus 120B determines, in step S362, whether the current time has reached the performance start timing. If the current time has not reached the performance start timing (NO), the control unit 122 repeats the process of step S362. If the current time has reached the performance start timing (YES), the control unit 122 transfers the process to step S372 to make the transfer.

[0084] The control units 122 of the image transmission / reception apparatuses 120A and 120C perform, in step S371, the performance At the start timing, a signal to notify the start of the performance is displayed on the display unit 295. In step S372, the control unit 122 of the image transmitting / receiving device 120B ends the performance. At the start timing, a signal to notify the start of the performance is displayed on the display unit 295. Terminate the.

[0085] As described above, in the image transmission system shown in FIG. The image transmitting device (image transmitting / receiving device 120A or 120C) includes a camera 11. The transmitting device receives an image generated by the camera 11 by photographing a subject performing a predetermined action. The image data is transmitted to an image receiving device (image transmitting device) located at a reference site via a network 30. The received signal is then transmitted to receiving device 120B.

[0086] The timing adjustment method performed in the image transmission system is a method for adjusting the timing of an image data received by an image receiving device. The delay time when the data is displayed on the display device 22 is measured. A delay time correction value based on the delay time is set in the timing instruction unit 29 arranged at the side site. The timing adjustment method is to adjust the timing by timing instruction unit 29 when the subject performs a predetermined action. A given operation is started at a time indicated by the delay time correction value before the time instructed to start. Cue the subject to let them know when to start shooting.

[0087] According to one or more embodiments of the timing adjustment method, a sending site and a reference site When image data of a subject performing a specific action, which is performed individually, is displayed at a reference point, The timing of the two can be adjusted to match.

[0088] <Frame timing adjustment method when receiving image data> With the configuration shown in FIG. 10, even if the timing of the start of performance is adjusted, the image transmission / reception apparatuses 12 The timing of the frames of the image data generated by 0A to 120C is shifted, and when displaying while switching the moving images generated by the image transmission / reception apparatuses 120A to 120C, image noise may occur. There may be occurrences.

[0089] FIG. 13 shows an image transmission / reception apparatus 120 configured to correct the shift in the timing of the frames of the image data, and a delay time management server 50 suitable for correcting the shift in the timing of the frames of the image data. In FIG. 13, similar to FIG. 10, the image transmission / reception apparatus 120B receives the image data transmitted from the image transmission / reception apparatuses 120A and 120C. .

[0090] The image transmission / reception apparatus 120B has a vertical synchronization delay circuit 123. The vertical synchronization delay circuit 123 receives the image data transmitted from the image transmission / reception apparatuses 120A and 120C received by the transmission / reception unit 121, and the image data output from the camera 11. The vertical synchronization signals of the image data transmitted from the image transmission / reception apparatuses 12 0A and 120C are assumed to be delayed with respect to the vertical synchronization signal of the image data output from the camera 11.

[0091] The vertical synchronization delay circuit 123 delays the vertical synchronization of the image data output from the camera 11 so as to reduce the shift in the vertical synchronization signal of the image data transmitted from the image transmission / reception apparatuses 120A and 120C with respect to the vertical synchronization signal of the image data output from the camera 11. When the shift amounts of the vertical synchronization signals of the image data transmitted from the image transmission / reception apparatuses 120A and 120C are different, the vertical synchronization delay circuit 123 uses the vertical synchronization of the image data with the smaller shift amount ​ Delay it and make it match the one with the larger deviation amount. The vertical synchronization delay circuit 123 delays the image data from the camera 11 by an amount corresponding to the deviation amount, thereby synchronizing the vertical synchronization of the three pieces of image data.

[0092] The vertical synchronization delay circuit 123 is for the vertical synchronization signal of the image data output from the camera 11 and supplies the first delay time of the vertical synchronization signal of the image data transmitted from the image transceiver device 120A and the second delay time of the vertical synchronization signal of the image data transmitted from the image transceiver device 120C to the transmission / reception unit 121. The vertical synchronization delay circuit 123 functions as a vertical synchronization deviation amount measurement unit that measures the first and second delay times.

[0093] Based on the control by the control unit 122, the transmission / reception unit 121 transmits the first and second delay times to the delay time management server 50 via the network 30. Assume that the first delay time is 3.2 m s and the second delay time is 0.3 ms.

[0094] As shown in FIG. 14, when the delay time management server 50 sets the base B1 as the transmission side and the base B2 as the reception side, it stores the delay time obtained by adding the first delay time of 3.2 ms to the delay time of 10.3 ms. Also, when the delay time management server 50 sets the base B3 as the transmission side and the base B2 as the reception side, it stores the delay time obtained by adding the second delay time of 0.3 ms to the delay time of 10.2 ms.

[0095] The delay time correction value holding units 294 of the timing instruction units 29 in the image transceiver devices 120A and 120C respectively hold the delay times (10.3 + 3.2) ms and (10.2 + 0.3 ) ms as delay time correction values. ​​​​​​​​

[0096] The control unit 291 of the timing instruction unit 29 in the image transmission / reception device 120A starts the performance at a time (10.3 + 3.2) ms before the time when the performance starts, which is the delay time correction value, and sends a signal notifying the timing to the display unit 295 for display. In the image transmission / reception device 120C, the control unit 291 of the timing instruction unit 29 sends a signal notifying the timing to start the performance at a time (10.2 + 0.3) ms before the time when the performance starts, which is the delay time correction value, to the display unit 295 for display.

[0097] As a result, the image data displayed on the display device 22 at the base B2 is not only displayed with the performance timings of all the bases B1 to B3 being matched, but also the deviation in the frame timing of the image data generated by the image transmission / reception devices 120A to 120C is corrected.

[0098] Over time, if the vertical synchronization signal of the image data output from the camera 11 is deviated from the vertical synchronization signal of the image data transmitted from the image transmission / reception device 120A or 120C, the vertical synchronization of the image data output from the camera 11 can be delayed by the vertical synchronization delay circuit 123 so as to reduce the deviation of the vertical synchronization signal.

[0099] Furthermore, the first delay time of the vertical synchronization signal of the image data transmitted from the image transmission / reception device 120A and the second delay time of the vertical synchronization signal of the image data transmitted from the image transmission / reception device 120C with respect to the vertical synchronization signal of the image data output from the camera 11 are transmitted to the delay time management server 50 and updated to the latest first and second delay times. Therefore, the frame timings of the image data generated by It is always corrected to the optimal state at each interval.

[0100] As described above, in the image transmission system shown in FIG. 13, via the network 30, An image transmission device (image transmission / reception device 120A or 12 0C) including the first camera (camera 11) and an image reception device including the second camera (camera 11) and the display device 22 are connected. The image reception device (image transmission / reception device 120B) includes a delay time measurement unit 28 and a vertical synchronization delay circuit 123 that functions as a vertical synchronization deviation amount measurement unit.

[0101] The delay time measurement unit 28 measures the delay time when the image reception device receives the first image data generated by the first camera and transmitted by the image transmission device to the image reception device and displays it on the display device 22. The vertical synchronization delay circuit 123 measures the vertical synchronization deviation amount indicating the time when the vertical synchronization between the first image data and the second image data generated by the second camera and displayed on the display device 22 is deviated. The delay time management server 50 stores the delay time and the vertical synchronization deviation amount transmitted from the image reception device via the network 30.

[0102] In the image transmission system shown in FIG. 13, the first camera included in the image transmission device arranged at the transmission-side base captures a first subject performing a predetermined operation, and the generated first image data is transmitted to the image reception device arranged at the reference base via the network 30. The timing adjustment method executed by the image transmission system measures the delay time when the image reception device displays the first image data received on the display device 22.

[0103] The timing adjustment method executed by the image transmission system includes the first image data and the image reception The second camera included in the device measures the vertical synchronization deviation amount indicating the time when the vertical synchronization with the second image data generated by photographing a second subject performing a predetermined operation is shifted. The timing adjustment method executed in the image transmission system sets a delay time correction value based on the delay time obtained by adding the delay time and the vertical synchronization deviation amount to the timing instruction unit 29 arranged at the transmission-side base point. The timing adjustment method executed in the image transmission system causes the timing instruction unit 29 to notify the first subject of the timing to start the predetermined operation at a time earlier by the time indicated by the delay time correction value from the time when the first subject is instructed to start the predetermined operation.

[0104] According to the delay time management server of one or more embodiments, when transmitting image data from the image transmission / reception device 120 operating as an image transmission device to the image transmission / reception device 120 operating as an image reception device via the network 30, more accurate delay time and vertical synchronization deviation amount can be managed. According to the timing adjustment method of one or more embodiments, the timing including the timing of the frame of the image data when displaying the image data photographed by the subject performing the predetermined operation individually performed at the transmission-side base point and the reference base point can be adjusted to match at the reference base point.

[0105]

[0106] The present invention is not limited to the one or more embodiments described above, and various modifications can be made without departing from the gist of the present invention.

Explanation of Reference Numerals

[0107] ​​​​​​​​​​​​​10, 10A to 10C Image Transmission Devices 11 Camera 12 Transmission Unit 13, 23 GNSS Satellite Radio Clock 14, 24 Clock Generation Unit 15, 27 Image Memory 16, 25 Communication Unit 20 Image Reception Device 21 Reception Unit 22 Display Device 26, 113 Image Processing Circuit 28 Delay Time Measurement Unit 29 Timing Instruction Unit 30 Network 40 Satellite 50 Delay Time Management Server 111, 122, 221 Control Unit 112 Imaging Element 120A to 120C Image Transmission / Reception Devices 121 Transmission / Reception Unit 123 Vertical Synchronization Delay Circuit (Vertical Synchronization Deviation Measurement Unit) 150, 270 Write / Read Control Unit 222 Driving Circuit 223 Liquid Crystal Panel

Claims

1. First and second image transmitting / receiving devices; a delay time management server that stores a delay time between the first and second transmitting / receiving devices; is a delay time management system that performs two-way communication via a network, the first image transmitting / receiving device measures a first time when an imaging element of a camera included in the first image transmitting / receiving device generates pixel data of a first reference pixel which is a pixel at a specific position in a specific row within a frame, and transmits the pixel data of the first reference pixel to the second transmitting / receiving device; the second image transmitting / receiving device measures a second time when a display device included in the second image transmitting / receiving device displays pixel data of the first reference pixel; The delay time management server stores a first delay time based on the first time and the second time. Delay time management system.

2. the second image transmitting / receiving device measures a third time when an imaging element of a camera included in the second image transmitting / receiving device generates pixel data of a second reference pixel, the second reference pixel being a pixel at a specific position in a specific row within a frame, and transmits the pixel data of the second reference pixel to the first transceiver; the first image transmitting / receiving device measures a fourth time when a display device included in the first image transmitting / receiving device displays pixel data of the second reference pixel; The delay time management server stores a second delay time based on the third time and the fourth time. The delay time management system according to claim 1.

3. 2. The delay time management system according to claim 1, wherein the first delay time is calculated by the second image transmitting / receiving device and transmitted to the delay time management server.

4. 3. The delay time management system according to claim 2, wherein the second delay time is calculated by the first image transmitting / receiving device and transmitted to the delay time management server.

Images