JP2022015118A - Wireless image transmission system, image display system and wireless image transmission method - Google Patents

Abstract

To provide an image transmission system by which an image with a bit rate corresponding to a position of a traveling train is sent to an image display device.SOLUTION: There are plural sections K on a route where a train MV1 travels. With each sections K, an image transmission bit rate that is a bit rate of the image to send the image to an image display device 200 from the prescribed section K is related. A position specification part 110 specifies either of the plural sections K as a travel position that is a position of a train MV1 traveling on the route. The plural sections K include travel sections that are specified as travel positions. An image processing part 130 generates a transmission image which is an image with a transmission image bit rate related with the travel section. A wireless communication part 150 transmits the generated transmission image to the image display unit 200 via a wireless route N1.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a wireless image transmission system, an image display system and a wireless image transmission method for transmitting an image via a wireless line.

Increasingly, images are transmitted to wireless mobile terminals using wireless lines. Patent Document 1 discloses a configuration in which an image is transmitted to a wireless mobile terminal using a wireless line (hereinafter, also referred to as “related configuration A”). In the related configuration A, the image display method is changed according to the quality of the wireless line.

Specifically, in the related configuration A, the radio base station transmits an image to a wireless mobile terminal via a wireless line. The wireless mobile terminal transmits the received image to the image display unit via the image display adapter. The image display adapter has a function of displaying an image on the image display unit.

The wireless mobile terminal monitors the quality of the wireless line between the wireless base station and the wireless mobile terminal. When the quality of the wireless line deteriorates, it is predicted that the image to be displayed by the image display unit will be deteriorated. The wireless mobile terminal notifies the image display adapter of the information necessary for dealing with the deterioration of the image. The information is information related to the image display control process. When image deterioration occurs, the image display adapter controls the image display unit so that the image display unit performs appropriate image display control processing based on the information.

The image display control process is, for example, a process in which the image display unit stops displaying an image. Further, the image display control process is, for example, a process of reducing the brightness of an image. Further, the image display control process is, for example, a process of displaying line quality information. By performing the image display control process by the image display unit, deterioration of the image can be made inconspicuous.

Japanese Patent No. 3669413

Increasingly, systems mounted on trains are used to transmit images to external image display devices via wireless lines. In such a configuration, the quality of the wireless line changes depending on the running of the train. Therefore, it is required to transmit an image having a bit rate corresponding to the position of the running train to the image display device so as to be able to cope with the change in the quality of the wireless line due to the running of the train. The related configuration A cannot meet this requirement.

The present disclosure has been made to solve such a problem, and is a wireless image transmission system or the like capable of transmitting an image having a bit rate corresponding to the position of a running train to an image display device. The purpose is to provide.

In order to achieve the above object, the wireless image transmission system according to one aspect of the present disclosure transmits an image to an external image display device via a wireless line. The wireless image transmission system is mounted on a train traveling on a predetermined route, and the route has a plurality of sections, and each of the sections displays an image from the section to the image display device. A transmission image bit rate, which is the bit rate of the image for transmission, is associated with the radio image transmission system at the position of the train traveling on the route in any of the plurality of sections. The plurality of sections include a traveling section which is a section specified as the traveling position, and the radio image transmission system is further associated with the traveling section. It includes an image processing unit that generates a transmission image that is an image having the transmission image bit rate, and a wireless communication unit that transmits the generated transmission image to the image display device via the wireless line. ..

According to the present disclosure, there are a plurality of sections in the route on which the train travels. Each of the sections is associated with a transmission image bit rate, which is the bit rate of the image for transmitting an image from the section to the image display device. The position specifying unit identifies any of the plurality of sections as a traveling position which is the position of the train traveling on the route. The plurality of sections include a traveling section which is a section specified as the traveling position. The image processing unit generates a transmission image which is an image having the transmission image bit rate associated with the traveling section. The wireless communication unit transmits the generated transmission image to the image display device via the wireless line.

This makes it possible to transmit an image having a bit rate corresponding to the position of the running train to the image display device.

It is a block diagram which shows the structure of the image display system which concerns on Embodiment 1. FIG. It is a figure which shows an example of a database. It is a flowchart of image transmission control processing which concerns on Embodiment 1. It is a block diagram which shows the structure of the image display system which concerns on modification 1 or modification 2. It is a block diagram which shows the structure of the image display system which concerns on modification 3. It is a block diagram which shows the characteristic functional composition of a wireless image transmission system. It is a hardware block diagram of a wireless image transmission system.

Hereinafter, embodiments will be described with reference to the drawings. In the following drawings, the same components are designated by the same reference numerals. The components with the same reference numerals and functions are the same. Therefore, detailed description of some of the components with the same reference numerals may be omitted.

<Embodiment 1>
(Constitution)
FIG. 1 is a block diagram showing a configuration of an image display system 1000 according to the first embodiment. The image display system 1000 includes a wireless image transmission system 100 and an image display device 200. The image display device 200 is a device existing outside the wireless image transmission system 100. The image display device 200 has a function of displaying an image and a function of performing wireless communication. The image display device 200 is, for example, a display. The image display device 200 is installed indoors. The indoor is, for example, the office of a railway operator.

The wireless image transmission system 100 has a function of performing wireless communication with the image display device 200 via the wireless line N1. The wireless image transmission system 100 transmits an image to the image display device 200 via, for example, the wireless line N1.

In the following, the image to be transmitted from the wireless image transmission system 100 to the image display device 200 is also referred to as “image G1”. The image G1 is an image encoded according to a predetermined coding method. The image G1 is encoded according to, for example, the MPEG2-TS method.

The wireless image transmission system 100 is mounted on the train MV1. The train MV1 travels on a predetermined route Rt. The path Rt is a railroad track. That is, the route on which the train MV1 travels is fixed. A plurality of sections K adjacent to each other exist in the path Rt.

Each section K is called "about a kilometer". Kilometers are expressed as the distance from the reference position. In the following, the three sections K included in the plurality of sections K are also referred to as sections K1, K2, and K3, respectively. The sections K1, K2, and K3 are adjacent to each other in the route Rt. The sections K1, K2, and K3 are, for example, the sections shown in FIG.

The section K1 is, for example, a section from the position P0 to the position P1. The position P0 is, for example, the starting point of the train MV1. The position P1 is a position separated from the position P0 by 12.4 km.

The wireless image transmission system 100 mounted on the train MV1 moves as the train MV1 travels (moves). In the following, the state of the wireless image transmission system 100 in a situation where the wireless image transmission system 100 is moving is also referred to as a “moving state”. The mobile image transmission system 100 passes through the sections K1, K2, and K3 in the order of, for example, the sections K1, K2, and K3. The mobile image transmission system 100 wirelessly communicates with the image display device 200 via the wireless line N1.

The wireless image transmission system 100 includes a position specifying unit 110, an image quality adjusting unit 120, an image processing unit 130, a camera 140, and a wireless communication unit 150. In the following, the position of the train MV1 traveling on the route Rt is also referred to as a “running position”. The traveling position is also the position of the wireless image transmission system 100.

The position specifying unit 110 has a function of specifying any one of the plurality of sections K as a traveling position. In the following, among the plurality of sections K, the section K specified as the traveling position is also referred to as a “traveling section”. That is, the plurality of sections K include the traveling section.

The position specifying unit 110 constantly grasps the traveling section as the traveling position. For example, it is assumed that the train MV1 is moving 12 km from the above-mentioned position P0. In this case, the position specifying unit 110 specifies the section K1 in FIG. 2 as a traveling section as a traveling position.

Although the details will be described later, the image quality adjusting unit 120 notifies the image processing unit 130 of the bit rate corresponding to the traveling section (traveling position).

The camera 140 has a function of taking a picture. The camera 140, for example, photographs a railroad track existing in front of the train MV1 as a subject. Further, the camera 140 captures, for example, a railroad track existing behind the train MV1 as a subject. Further, the camera 140 captures, for example, an overhead wire provided on the train MV1 as a subject. Further, the camera 140 takes a picture of the space in the train MV1 as a subject, for example. In this case, the camera 140 functions as a security camera.

In the following, the image obtained by the camera 140 taking a picture is also referred to as a “shooting image”. The captured image is a moving image. The captured image is a high bit rate image. The high bit rate is, for example, a bit rate included in the range of 2 Mbps to 4 Mbps. In the following, a high bit rate image is also referred to as a “high bit rate image”. The high bit rate image is an image obtained by taking a picture with the camera 140. The camera 140 continuously transmits a captured image, which is a high bit rate image, to the image processing unit 130.

The image processing unit 130 continuously receives captured images from the camera 140. The image processing unit 130 uses the captured image to generate an image having the bit rate notified by the image quality adjusting unit 120. That is, the image processing unit 130 changes the bit rate of the captured image. The image processing unit 130 transmits the generated image as the image G1 to the wireless communication unit 150.

The wireless communication unit 150 has a function of performing wireless communication with the image display device 200 via the wireless line N1. The wireless communication unit 150 transmits the image G1 to the image display device 200 via the wireless line N1.

The image display device 200 has a function of decoding the image G1. Further, the image display device 200 has a function of performing decoding processing and display processing, although the details will be described later. The decoding process is a process of decoding the image G1. The display process is a process of displaying the decoded image G1.

In the following, the speed at which data is transmitted on the wireless line N1 is also referred to as a “line transmission speed”. The line transmission speed is expressed as a bit rate. Further, in the following, the quality of the wireless line N1 is also referred to as "line quality" or "wireless transmission quality". The line quality corresponding to each section K is different.

Further, the wireless communication unit 150 has a function of measuring the line quality of the wireless line N1. The wireless communication unit 150 performs a line quality measurement process for measuring the line quality, and measures the line quality. The line quality measuring method in the line quality measuring process is, for example, a known method using a CRC code method for detecting a transmission error in data communication. For example, in a situation where data communication is performed between the wireless communication unit 150 and the image display device 200 using the wireless line N1, the wireless communication unit 150 performs line quality measurement processing to perform the line quality. To measure.

In this embodiment, the number of line quality types is 3 for the sake of clarity. In the following, the three types of line qualities are expressed as q1, q2, and q3, respectively. "Q1" has the worst line quality. "Q3" has the best line quality. “Q2” is the quality between “q1” and “q3”. In a situation where the line quality is q3, for example, a transmission error does not occur in a situation where data communication is performed using the wireless line N1. In a situation where the line quality is q1, for example, in a situation where data communication is performed using the wireless line N1, a large number of transmission errors occur. The number of types of line quality may be 4 or more.

In the following, the bit rate of the image G1 for transmitting the image G1 from the section K to the image display device 200 is also referred to as a “transmission image bit rate”. The value of the transmitted image bit rate differs depending on the line quality corresponding to the section K. In the present embodiment, the transmission image bit rate is associated with each section K. The state of association between each section K and the transmitted image bit rate is shown by the database Db1.

The image quality adjusting unit 120 has a database Db1. That is, the wireless image transmission system 100 has a database Db1. The database Db1 is, for example, the database Db1 of FIG. The “bit rate” in FIG. 2 is a transmitted image bit rate. In the database Db1 of FIG. 2, for example, the section K2 is associated with a transmission image bit rate of “200 kbps”.

(motion)
Next, an image transmission control process, which is a characteristic process performed by the wireless image transmission system 100 according to the first embodiment, will be described. The image transmission control process is a process for transmitting the image G1 to the image display device 200. In order to make it easier to understand an example of the image transmission control process, the image transmission control process performed under the following premise Pm1 will be described.

In the premise Pm1, the image quality adjusting unit 120 has the database Db1 of FIG. The database Db1 is created by performing the database creation process before the image transmission control process is performed.

The database creation process is performed by the wireless image transmission system 100 in the mobile state. In the database creation process, the line quality measurement process and the image bit rate setting process are performed in each section K.

First, the wireless communication unit 150 measures the line quality by performing the line quality measurement process. In the following, the measured line quality is also referred to as “measured line quality”. Further, in the following, the bit rate of the image is also referred to as an “image bit rate”.

The wireless image transmission system 100 stores in advance image bit rates associated with each of a plurality of different line qualities (q1, q2, q3). The image bit rate associated with each line quality is an image bit rate suitable for the line quality.

The image bit rate suitable for the line quality is a bit rate preset by experiments or the like. In the experiment, for example, a process of transmitting an image G1 having a different image bit rate from the wireless communication unit 150 to the image display device 200 via the wireless line N1 is repeatedly performed. Then, in a situation where the line quality is any of q1, q2, and q3, the image bit rate for the image G1 to be normally transmitted to the image display device 200 is determined. When the line quality is "q2", the image bit rate suitable for the "q2" is, for example, 400 kbps.

In this experiment, the above steps are repeated while changing the line quality until an image bit rate suitable for each of the line qualities q1, q2, and q3 is determined.

Next, the image bit rate setting process is performed. In the image bit rate setting process, the image quality adjustment unit 120 determines the image bit rate associated with the measurement line quality as the transmission image bit rate. Then, the image quality adjusting unit 120 associates the determined transmission image bit rate with the section K.

Here, in order to explain an example of processing, it is assumed that the position of the train MV1 (wireless image transmission system 100) is a position within the section K1. Further, it is assumed that the measurement line quality is "q2". Further, it is assumed that the image bit rate associated with "q2" is 400 kbps.

In this case, in the image bit rate setting process, the image quality adjusting unit 120 determines the image bit rate (400 kbps) associated with the measurement line quality “q2” as the transmission image bit rate. The image quality adjusting unit 120 associates the determined transmission image bit rate (400 kbps) with the section K1 (see FIG. 2).

In the database creation process, the line quality measurement process and the image bit rate setting process are repeatedly performed in each section K due to the movement of the train MV1 (wireless image transmission system 100). As a result, for example, the database Db1 of FIG. 2 is created. As a result, the image quality adjusting unit 120 has the created database Db1. The database Db1 shows the section K in association with the transmission image bit rate corresponding to the section K.

Next, the image transmission control process will be described. The image transmission control process is performed in a situation where the train MV1 (wireless image transmission system 100) is moving. FIG. 3 is a flowchart of the image transmission control process according to the first embodiment. In the image transmission control process in the premise Pm1, first, the position specifying process is performed (step S110).

In the position specifying process, the position specifying unit 110 identifies any of the plurality of sections K in the database Db1 as the traveling position. The section K specified as the traveling position is a traveling section. That is, the database Db1 shows the traveling section and the transmission image bit rate corresponding to the traveling section in association with each other.

Next, the image quality adjusting unit 120 notifies the image processing unit 130 of the transmission image bit rate associated with the traveling section in the database Db1 of FIG. When the traveling section is the section K1, the transmission image bit rate notified to the image processing unit 130 is 400 kbps.

Next, an image generation process is performed (step S120). In the following, an image having a transmission image bit rate associated with a traveling section is also referred to as a “transmission image”. In the image generation process, the image processing unit 130 uses the captured image received from the camera 140 to generate a transmission image having the notified transmission image bit rate.

Specifically, the image processing unit 130 encodes the captured image according to a predetermined coding method so that the bit rate of the captured image becomes the transmission image bit rate, and generates a transmission image. The coding method is, for example, the MPEG2-TS method. The transmission image is an image showing the content of the captured image. The image quality of the generated transmission image is higher as the bit rate of the transmission image is higher. Further, the amount of data of the generated transmission image increases as the bit rate of the transmission image increases.

Here, it is assumed that the bit rate of the captured image is 2 Mbps and the transmitted image bit rate is 400 kbps. In this case, the image quality of the generated transmission image is lower than the image quality of the original captured image. The transmission image is an image G1 for transmission to the image display device 200.

Further, the image processing unit 130 transmits the generated image G1 for transmission to the wireless communication unit 150.

Next, image transmission processing is performed (step S130). In the image transmission process, the wireless communication unit 150 transmits the generated image G1 for transmission to the image display device 200 via the wireless line N1.

In the following, the process performed by the image display device 200 corresponding to the image transmission control process is also referred to as “display device side process”.

In the display device side processing, the image display device 200 performs the decoding process and the display process in parallel. In the decoding process, the image display device 200 decodes the image G1 transmitted from the wireless communication unit 150. In the display process, the image display device 200 displays the decoded image G1.

(summary)
As described above, according to the present embodiment, there are a plurality of sections K in the route on which the train MV1 travels. Each section K is associated with a transmission image bit rate, which is the bit rate of the image for transmitting an image from the section K to the image display device 200. The position specifying unit 110 identifies any of the plurality of sections K as a traveling position which is the position of the train MV1 traveling on the route. The plurality of sections K include a traveling section which is a section specified as a traveling position. The image processing unit 130 generates a transmission image which is an image having a transmission image bit rate associated with the traveling section. The wireless communication unit 150 transmits the generated transmission image to the image display device 200 via the wireless line N1.

This makes it possible to transmit an image having a bit rate corresponding to the position of the running train to the image display device.

Further, in the present embodiment, the line quality that changes depending on the traveling position is measured in advance. Further, a bit rate suitable for the line quality corresponding to the traveling position is set in advance. Then, an image having a set bit rate is transmitted. Therefore, even if the line quality is deteriorated, the normal image can be continuously transmitted to the image display device 200. The normal image is an image that can be normally displayed by the image display device 200. The normal image displayed by the image display device 200 is an image that can be visually recognized by the user. The normal image is an image in which there is no deterioration in image quality (for example, block noise).

By the way, in the above-mentioned related configuration A, in order to cope with the change in the line quality, the image display method is changed according to the line quality. In the related configuration A, when the line quality deteriorates, the data size of the image to be transmitted is not changed. Further, in the related configuration A, for example, the display of the image is stopped in a state where it is allowed that the image transmission cannot be performed normally. Therefore, there is a problem that the image cannot be confirmed when the line quality is deteriorated. The problem arises in the situation of transmitting an image having a data amount larger than the data amount that can be transmitted by a wireless line.

Therefore, the wireless image transmission system 100 of the present embodiment has a configuration for achieving the above effects. Therefore, the wireless image transmission system 100 of the present embodiment can solve the above problem.

<Modification 1>
The configuration of this modification is applied to the first embodiment. In the first embodiment, the transmission image bit rate corresponding to the traveling section as the traveling position is set to a fixed value based on the line quality measured in advance.

The line quality of the wireless line N1 changes due to the disturbance. The disturbance is, for example, a change in the arrangement of buildings and the like existing around each section K. Therefore, immediately after the database Db1 is created, there is a problem that the transmission image bit rate indicated by the database Db1 may become an inappropriate bit rate with the passage of time even if it is the optimum bit rate. be. The configuration of this modification is a configuration corresponding to the above problem.

(Constitution)
FIG. 4 is a block diagram showing the configuration of the image display system 1000 according to the first modification. The image display system 1000 according to the first modification is different from the image display system 1000 according to the first embodiment in the processing performed by the wireless communication unit 150 of the wireless image transmission system 100. Since the other configurations of the image display system 1000 according to the first modification are the same as those of the image display system 1000 according to the first embodiment, detailed description thereof will not be repeated.

In the configuration of this modification, the wireless communication unit 150 notifies the image quality adjustment unit 120 of the transmission image bit rate. A communication interface is provided between the wireless communication unit 150 and the image quality adjustment unit 120.

(motion)
Next, an image transmission control process, which is a characteristic process performed by the wireless image transmission system 100 according to the first modification, will be described. In the following, the image transmission control process according to the first modification is also referred to as “image transmission control process A”. The image transmission control process A is performed in a situation where the train MV1 (wireless image transmission system 100) is moving. A part of the image transmission control process A is the same as the image transmission control process of FIG.

Hereinafter, the image transmission control process A will be mainly described as being different from the image transmission control process of the first embodiment. In the image transmission control process A, the position identification process of step S110 in FIG. 3, the image generation process of step S120, and the image transmission process of step S130 are performed as in the first embodiment. By the position specifying process, the traveling section (section K) as the traveling position is specified. Further, a transmission image (image G1) is generated by the image generation process, and the transmission image is transmitted to the wireless communication unit 150. Further, the image transmission process is executed in the same manner as in the first embodiment.

In the image transmission control process A of this modification, the above-mentioned line quality measurement process is performed together with the execution of the image transmission process. The image bit rate associated with each of a plurality of different line qualities (q1, q2, q3) is stored in advance in the wireless communication unit 150 of this modification. As described above, the image bit rate associated with each line quality is an image bit rate suitable for the line quality, which is preset by experiments or the like.

The wireless communication unit 150 measures the line quality corresponding to the traveling section by performing the line quality measurement process. The measured line quality is the measured line quality.

After the line quality measurement process is completed, the image transmission control process A performs the bit rate notification process. In the following, the transmission image bit rate for notifying the image quality adjustment unit 120 is also referred to as a “notification bit rate”.

In the bit rate notification process, the wireless communication unit 150 determines the image bit rate stored in the wireless communication unit 150, which is associated with the measurement line quality, as the notification bit rate. That is, the notification bit rate is a bit rate corresponding to the measurement line quality. Next, the wireless communication unit 150 notifies the image quality adjustment unit 120 of the notification bit rate.

Here, in order to explain an example of the processing, it is assumed that the traveling section specified by the position specifying processing is the section K1. Further, it is assumed that the measurement line quality is, for example, "q1". Further, it is assumed that the image bit rate associated with "q1" stored in the wireless communication unit 150 is 200 kbps.

In this case, in the bit rate notification process, the wireless communication unit 150 notifies the image bit rate (200 kbps) stored in the wireless communication unit 150 associated with the measurement line quality “q1” for the section K1. Determined as the bit rate. Next, the wireless communication unit 150 notifies the image quality adjustment unit 120 of the determined notification bit rate.

After the end of the bit rate notification process, in the image transmission control process A, the image quality adjusting unit 120 determines whether or not the transmitted image bit rate corresponding to the traveling section is different from the notification bit rate. When the transmission image bit rate corresponding to the traveling section is different from the notification bit rate, the image transmission control process A performs the database update process. On the other hand, when the transmission image bit rate corresponding to the traveling section is the same as the notification bit rate, the image transmission control process A ends.

In the database update process, the image quality adjustment unit 120 changes the transmission image bit rate associated with the traveling section indicated by the database Db1 to the notification bit rate corresponding to the measurement line quality, thereby causing the transmission image bit rate. And the database Db1 is updated.

Here, in order to explain an example of processing, it is assumed that the traveling section is the section K1. The notification bit rate is assumed to be 200 kbps. In this case, the image quality adjustment unit 120 updates the transmission image bit rate and the database Db1 by changing the transmission image bit rate (400 kbps) associated with the section K1 indicated by the database Db1 to 200 kbps. The image bit rate "200 kbps" associated with the interval K1 indicated by the updated database Db1 is the transmitted image bit rate after the update.

After the database update process is completed, the image transmission control process A ends. Such image transmission control process A is repeatedly performed during the period in which the train MV1 (wireless image transmission system 100) is moving.

Further, the image display device 200 performs the above-mentioned display device side processing in the same manner as in the first embodiment in accordance with the image transmission control process A.

(summary)
As described above, according to this modification, the line quality is measured during the period when the train MV1 (wireless image transmission system 100) is moving. Then, the image quality adjusting unit 120 updates the database Db1 by changing the transmission image bit rate associated with the traveling section indicated by the database Db1 to a bit rate corresponding to the measured line quality.

Therefore, it is possible to cope with changes in line quality corresponding to the traveling section due to disturbance. Therefore, even in a situation where the line quality corresponding to the traveling section has changed, the effect that the normal image can be continuously transmitted to the image display device 200 can be obtained as in the first embodiment.

<Modification 2>
The configuration of this modification is applied to the first embodiment. In the first modification, the wireless communication unit 150 measures the line quality, and the image quality adjustment unit 120 updates the database Db1 using the bit rate corresponding to the line quality, so that the line quality changes due to disturbance. Corresponded to.

The configuration of this modification corresponds to a change in line quality by feeding back the reception state of the image in the image display device 200 to the image quality adjusting unit 120.

(Constitution)
The block diagram of the image display system 1000 according to the present modification is the same as the block diagram of the image display system 1000 according to the modification 1 shown in FIG. In this modification, the image quality adjustment unit 120 notifies the image processing unit 130 of the transmission image bit rate and the section K (about a kilometer) at any time.

Further, the image processing unit 130 transmits an image to the wireless communication unit 150 and notifies the wireless communication unit 150 of the section K. The wireless communication unit 150 transmits the image G1 to the image display device 200, and notifies the image display device 200 of the section K and the bit rate of the image G1 (transmission image). Further, the wireless communication unit 150 notifies the image display device 200 of the measurement line quality.

(motion)
Next, the image transmission control process, the database update process B described later, and the display device side process, which are characteristic processes performed by the image display system 1000 according to the second modification, will be described. In the following, the image transmission control process according to the modification 2 is also referred to as “image transmission control process B”. The image transmission control process B is performed by the wireless image transmission system 100. Further, in the following, the display device side process according to the modification 2 is also referred to as “display device side process B”. The display device side process B is a process performed by the image display device 200 in response to the image transmission control process B.

The image transmission control process B is performed in a situation where the train MV1 (wireless image transmission system 100) is moving. A part of the image transmission control process B is the same as the image transmission control process of FIG.

Hereinafter, the image transmission control process B will be mainly described as being different from the image transmission control process of the first embodiment. In the image transmission control process B, the position identification process, the image generation process, and the image transmission process are performed as in the first embodiment. By the position specifying process, the traveling section (section K) as the traveling position is specified. Further, the image quality adjusting unit 120 notifies the image processing unit 130 of the transmission image bit rate and the section K.

Further, a transmission image (image G1) is generated by the image generation process, and the transmission image is transmitted to the wireless communication unit 150. Further, the image processing unit 130 notifies the wireless communication unit 150 of the section K. Further, the image transmission process is executed in the same manner as in the first embodiment.

By the image transmission process, the wireless communication unit 150 transmits the generated image G1 for transmission to the image display device 200 via the wireless line N1. In the following, the image G1 received by the image display device 200 by executing the image transmission process is also referred to as a “received image”.

In the image transmission control process B of this modification, the above-mentioned line quality measurement process is performed together with the execution of the image transmission process. The wireless communication unit 150 measures the line quality corresponding to the traveling section (section K) by performing the line quality measurement process. The measured line quality is the measured line quality.

After the line quality measurement process is completed, the image transmission control process B performs the notification process B. In the notification process B, the wireless communication unit 150 of the wireless image transmission system 100 notifies the image display device 200 of the section K (traveling section), the bit rate of the image G1 (transmission image), and the measurement line quality. ..

Such image transmission control process B is repeatedly performed during the period during which the train MV1 (wireless image transmission system 100) is moving.

Further, in the display device side process B, the image display device 200 performs the notification correspondence process and the decoding process in response to the image transmission process and the notification process B described above. Further, in the display device side process B, the image display device 200 performs all or part of the display process, the information recording process, and the bit rate change instruction process Pa (Pb) as necessary.

In the notification handling process, the image display device 200 recognizes the section K, the bit rate of the image G1, and the measurement line quality notified to the image display device 200 by executing the notification process B. In the following, the bit rate of the image G1 recognized by the image display device 200 is also referred to as an “image bit rate”.

By the way, for example, when the line quality is deteriorated due to a disturbance, the reception state of the image G1 which is a received image is deteriorated in the image display device 200. For example, a data reception error or the like necessary for decoding the image G1 occurs. Therefore, when the reception state of the image G1 deteriorates, there is a possibility that a situation in which the image G1 cannot be normally decoded (hereinafter, also referred to as a “decoding impossible situation”) may occur in the decoding process. In the following, the image G1 that cannot be normally decoded in the decoding process is also referred to as a “decoding impossible image”.

When a decoding impossible situation occurs, the display device side process B performs information recording process and bit rate change instruction process Pa. In the information recording process, the image display device 200 records the measurement line quality and the image bit rate of the undecodable image in association with each other. The image bit rate of the undecodable image is the image bit rate of the image G1 notified to the image display device 200 by the notification process B.

In the bit rate change instruction processing Pa, the image display device 200 transmits the change instruction A to the wireless image transmission system 100. Specifically, the image display device 200 transmits the change instruction A to the image quality adjusting unit 120 via the wireless communication unit 150.

The change instruction A is an instruction for lowering the transmission image bit rate associated with the section K corresponding to the undecodable image by a predetermined value Va. The predetermined value Va is, for example, a value included in the range of 5 kbps to 10 kbps. That is, the change instruction A is an instruction for changing the transmission image bit rate associated with the section K. Further, the change instruction A also indicates a section K notified to the image display device 200 by the notification process B.

As described above, when a decoding impossible situation occurs in the decoding process, the bit rate change instruction process Pa is performed. That is, the image display device 200 transmits the change instruction A to the wireless image transmission system 100 based on the reception state of the image G1 (transmission image) transmitted from the wireless communication unit 150. For the transmission of the change instruction A, various information notified by the notification process B is used. Further, the change instruction A is transmitted after the notification by the notification process B is performed. Therefore, the image display device 200 transmits the change instruction A to the wireless image transmission system 100 in response to the notification by the notification process B.

When the wireless image transmission system 100 receives the change instruction A, the wireless image transmission system 100 performs the database update process B independently of the image transmission control process B.

In the database update process B, the image quality adjustment unit 120 of the wireless image transmission system 100 changes the transmission image bit rate associated with the section K indicated by the database Db1 based on the change instruction A, so that the database Db1 To update.

Here, in order to explain an example of processing, it is assumed that the section K indicated by the change instruction A is the section K1. Further, it is assumed that the predetermined value Va is 10 kbps. In this case, in the database update process B, the image quality adjustment unit 120 updates the database Db1 by changing the transmission image bit rate (400 kbps) associated with the section K1 to 390 kbps.

Next, in the decoding process, the process in the state where the decoding impossible situation does not occur will be described. In the following, a situation in which a decoding impossible situation does not occur in the decoding process is also referred to as a “decoding possible situation”. Further, in the following, the image G1 normally decoded in the decoding process is also referred to as a “decodeable image”.

In the display device side process B in the decodetable situation, the decode process and the display process are performed in parallel. In the decoding process, the image display device 200 decodes the image G1 transmitted from the wireless communication unit 150. In the display process, the image display device 200 displays the decoded image G1.

Further, the information recording process is performed in the display device side process B in the decodable state. In the information recording process, the image display device 200 records the measurement line quality and the image bit rate of the decodable image in association with each other. The image bit rate of the decodable image is the image bit rate of the image G1 notified to the image display device 200 by the notification process B.

Further, in the display device side processing B in the decodetable situation, the image bit rate of the image G1 notified by the notification processing B is lower than the bit rate determined for each line quality, and the difference value described later is a predetermined value. If it is Va or more, the bit rate change instruction process Pb is performed. The difference value is a value obtained by subtracting the image bit rate of the image G1 from the bit rate determined for each line quality. The bit rate defined for each line quality is an image bit rate associated with each of a plurality of different line qualities (q1, q2, q3). The image display device 200 stores in advance the image bit rates associated with each of the plurality of line qualities (q1, q2, q3).

On the other hand, when the image bit rate of the image G1 is equal to or higher than the bit rate determined for each line quality, the bit rate change instruction process Pb is not performed.

Here, in order to explain an example of the processing, it is assumed that the measurement line quality notified to the image display device 200 by the notification processing B is “q2”. Further, it is assumed that the image bit rate associated with the line quality q2 is 400 kbps. Further, it is assumed that the image bit rate of the image G1 notified by the notification process B is 300 kbps. Further, it is assumed that the difference value obtained by subtracting the image bit rate (300 kbps) of the image G1 from the image bit rate (400 kbps) associated with the line quality q2 is a predetermined value Va or more.

In this case, the image bit rate (300 kbps) of the image G1 notified by the notification process B is lower than the image bit rate (400 kbps) associated with the line quality q2, and the difference value is a predetermined value Va or more. The bit rate change instruction process Pb is performed.

In the bit rate change instruction process Pb, the image display device 200 transmits the change instruction B to the wireless image transmission system 100. Specifically, the image display device 200 transmits the change instruction B to the image quality adjusting unit 120 via the wireless communication unit 150.

The change instruction B is an instruction for increasing the transmission image bit rate associated with the section K corresponding to the decodable image by a predetermined value Va. The predetermined value Va is, for example, a value included in the range of 5 kbps to 10 kbps. That is, the change instruction B is an instruction for changing the transmission image bit rate associated with the section K. Further, the change instruction B also indicates a section K notified to the image display device 200 by the notification process B.

When the wireless image transmission system 100 receives the change instruction B, the wireless image transmission system 100 performs the database update process B independently of the image transmission control process B. In the database update process B, the image quality adjustment unit 120 of the wireless image transmission system 100 changes the transmission image bit rate associated with the section K indicated by the database Db1 based on the change instruction B, thereby changing the database Db1. To update.

Here, in order to explain an example of processing, it is assumed that the section K indicated by the change instruction B is the section K1. Further, it is assumed that the predetermined value Va is 10 kbps. In this case, in the database update process B, the image quality adjustment unit 120 updates the database Db1 by changing the transmission image bit rate (400 kbps) associated with the section K1 to 410 kbps.

As described above, the image transmission control process B is repeated. That is, the position specifying process, the image generation process, the image transmission process, the line quality measurement process, and the notification process B are repeatedly performed.

In the display device side processing B, every time the image transmission processing and the notification processing B are performed, all or part of the notification correspondence processing, the decoding processing, the display processing, the information recording processing, and the bit rate change instruction processing Pa (Pb) are performed. As mentioned above, it is done.

In the display device side process B, the bit rate change instruction process Pa or the bit rate change instruction process Pb is not performed each time the image transmission process and the notification process B are performed (hereinafter, also referred to as “transformation configuration A”). ) May be used.

In the modified configuration A, the decoding process and the information recording process are performed each time the image transmission process and the notification process B are performed. By performing the decoding process and the information recording process a plurality of times, the image display device 200 aggregates the number of occurrences of the undecodable state and the decodable state for the image having the image bit rate corresponding to each line quality. Then, the image display device 200 performs the following processing when a decoding impossible situation occurs at a predetermined ratio (for example, 20%) with respect to an image having a bit rate determined for each line quality.

In this process, the image display device 200 transmits an instruction for lowering the bit rate determined for each line quality by a predetermined value Va to the wireless image transmission system 100. The predetermined value Va is, for example, a value included in the range of 5 kbps to 10 kbps.

The image quality adjusting unit 120 of the wireless image transmission system 100 updates the database Db1 by lowering the bit rate determined for each line quality by a predetermined value Va in the database Db1 according to the above instructions.

(summary)
As described above, according to the present modification, the section as the traveling section (traveling position) indicated by the database Db1 in consideration of the line quality of the wireless line N1 and the image reception state in the image display device 200. The database Db1 is updated by changing the transmitted image bit rate associated with K. As a result, it is possible to more accurately respond to changes in line quality corresponding to the traveling section due to disturbance than in the first embodiment and the first modification. Therefore, even in a situation where the line quality corresponding to the traveling section has changed, the effect that the normal image can be continuously transmitted to the image display device 200 can be obtained as in the first embodiment.

<Modification 3>
The configuration of this modification is applied to all or a part of the first embodiment, the first modification and the second modification. In the configuration of this modification, the image display device 200 records the image in the recording device 210 described later while the image display device 200 displays the image. Further, the configuration of this modification is a configuration in which a low bit rate image recorded in the recording device 210 is updated with a high bit rate image.

(Constitution)
FIG. 5 is a block diagram showing the configuration of the image display system 1000 according to the modified example 3. Hereinafter, the configuration of the present modification will be described as an example of the configuration applied to the modification 2. The image display system 1000 according to the modification 3 is different from the image display system 1000 of FIG. 4 according to the modification 2 in that the image display system 1000 further includes a recording device 210. Since the other configurations of the image display system 1000 according to the modification 3 are the same as those of the image display system 1000 of FIG. 4 according to the modification 2, detailed description will not be repeated.

The recording device 210 has a function of storing an image. The recording device 210 is, for example, an HDD (Hard Disk Drive). The recording device 210 is connected to the image display device 200. The image display device 200 has a function of recording an image received from the wireless image transmission system 100 on the recording device 210.

In this modification, the image quality adjustment unit 120 notifies the image processing unit 130 of the transmission image bit rate and the section K (about a kilometer) at any time. The image processing unit 130 transmits an image to the wireless communication unit 150 and notifies the wireless communication unit 150 of the section K. The wireless communication unit 150 transmits the image G1 to the image display device 200, and notifies the image display device 200 of the section K and the bit rate of the image G1 (transmission image). Further, the wireless communication unit 150 notifies the image display device 200 of the measurement line quality.

Further, the image processing unit 130 of this modification has a function of storing an image.

(motion)
Next, the image transmission control process and the display device side process, which are characteristic processes performed by the image display system 1000 according to the third modification, will be described. In the following, the image transmission control process according to the modification 3 is also referred to as “image transmission control process C”. The image transmission control process C is performed by the wireless image transmission system 100. Further, in the following, the display device side process according to the modification 3 is also referred to as “display device side process C”. The display device side process C is a process performed by the image display device 200 in response to the image transmission control process C.

The image transmission control process C is performed in a situation where the train MV1 (wireless image transmission system 100) is moving. The image transmission control process C is a process in which a process described later is added to the image transmission control process B of the modification 2.

Hereinafter, the configuration of the present modification will be described as an example of the processing of the configuration applied to the modification 2. The image transmission control process C will be mainly described as being different from the image transmission control process B of the modification 2.

In the image transmission control process C, the position identification process, the image generation process, and the image transmission process are performed as in the modification 2. By the position specifying process, the traveling section (section K) as the traveling position is specified. Further, the image quality adjusting unit 120 notifies the image processing unit 130 of the transmission image bit rate and the section K.

Further, a transmission image (image G1) is generated by the image generation process, and the transmission image is transmitted to the wireless communication unit 150. Further, the image processing unit 130 notifies the wireless communication unit 150 of the section K.

Further, in the image transmission control process C of this modification, the high bit rate image storage process is performed together with the execution of the image generation process. In the high bit rate image storage process, the image processing unit 130 stores the high bit rate image (photographed image) received from the camera 140 in association with the section K.

Further, the image transmission process is executed in the same manner as in the second modification. By the image transmission process, the wireless communication unit 150 transmits the image G1 (transmission image) to the image display device 200 via the wireless line N1.

In the image transmission control process C of this modification, the above-mentioned line quality measurement process is performed together with the execution of the image transmission process. The wireless communication unit 150 measures the line quality corresponding to the traveling section (section K) by performing the line quality measurement process. The measured line quality is the measured line quality.

After the line quality measurement process is completed, the image transmission control process C performs the notification process B in the same manner as in the modification 2.

In the notification process B, the wireless communication unit 150 of the wireless image transmission system 100 notifies the image display device 200 of the section K (traveling section), the bit rate of the image G1 (transmission image), and the measurement line quality. ..

Such image transmission control process C is repeatedly performed during the period during which the train MV1 (wireless image transmission system 100) is moving. Therefore, the position specifying process, the image generation process, the high bit rate image storage process, the image transmission process, the line quality measurement process, and the notification process B are repeatedly performed. That is, the high bit rate image storage process is repeatedly performed. As a result, the image processing unit 130 stores the high bit rate image corresponding to each section K in association with the section K. For example, the image processing unit 130 stores high bit rate images corresponding to each of the sections K1, K2, and K3, which are the sections K, in association with the section K.

In addition, the image transmission process is repeated. As a result, the wireless image transmission system 100 performs an image transmission process of transmitting the image G1 (transmission image) to the image display device 200 via the wireless line N1 in each section K.

Further, in the display device side process C, the image display device 200 performs the notification correspondence process and the decoding process in the same manner as in the modification 2, in response to the image transmission process and the notification process B described above. Further, in the display device side process C, the image display device 200 performs all or part of the display process, the information recording process, and the bit rate change instruction process Pa (Pb) as necessary, as in the modification 2. ..

In the following, the period during which the image display device 200 receives the image G1 (image for transmission) is also referred to as an “image reception period”. Here, it is assumed that the display processing is performed without the above-mentioned non-decoding situation occurring in the decoding processing. In this case, in the display process, the image display device 200 displays the decoded image G1 (transmission image).

In the following, the image displayed by the image display device 200 in the display process is also referred to as a “live image”. A live image is an image that is played back by streaming. That is, the live image is an image G1 displayed by the image display device 200 while the image display device 200 receives the image G1. The live image is an image corresponding to the measurement line quality in the section K. In the display process, the image display device 200 displays the image G1 (transmission image) as a live image during the image reception period. The displayed live image is an image that can be visually recognized by the user.

Further, in the display device side process C of this modification, the display image recording process is performed together with the execution of the display process. The display process and the display image recording process are performed in parallel.

In the display image recording process, the image display device 200 performs a recording process of recording the same image G1 (transmission image) as the live image in the recording device 210 in association with the section K during the image reception period. That is, the image display device 200 records the same image as the image on the recording device 210 while displaying the image.

Further, in the display device side process C of this modification, the line quality determination process is performed in response to the notification process B. In the line quality determination process, the image display device 200 determines whether or not the notified measurement line quality corresponding to the section K is of the standard high quality. Standard high quality is standard quality or higher quality than standard quality. That is, the image display device 200 determines whether or not the quality of the measurement line corresponding to the section K is equal to or higher than the standard quality. The standard quality is, for example, the above-mentioned line quality “q3”.

When the measurement line quality corresponding to the section K is a quality equal to or higher than the standard quality (standard high quality), the high bit rate image request processing described later is performed. If the measurement line quality corresponding to the section K is not higher than the standard quality (standard high quality), the high bit rate image request processing is not performed. Further, when the high bit rate image request processing is performed, the display device side processing C performs the recorded image update processing described later.

As described above, the image transmission control process C is repeated. That is, the position specifying process, the image generation process, the high bit rate image storage process, the image transmission process, the line quality measurement process, and the notification process B are repeatedly performed.

In the display device side processing C, each time the image transmission processing and the notification processing B are performed, the notification correspondence processing, the decoding processing, the display processing, the display image recording processing, the information recording processing, the bit rate change instruction processing Pa (Pb), and the line are performed. All or part of the quality determination process, the high bit rate image request process described later, and the recorded image update process described later are performed.

When the bit rate change instruction process Pa (Pb) is performed, the database update process B is performed by the wireless image transmission system 100 in the same manner as in the modification 2.

In this modification, it will be described that the display image recording process is repeatedly performed corresponding to the image transmission process corresponding to each of the plurality of sections K. By repeating the display image recording process (recording process), the image G1 (transmission image) corresponding to each of the plurality of sections K is recorded in the recording device 210.

In the following, the day when the image G1 (transmission image) corresponding to each of the plurality of sections K is recorded in the recording device 210 is also referred to as “day A”. Further, in the following, the day after the day A is also referred to as "day B". Further, in the following, any section of the plurality of sections K is also referred to as “section Kx”. The section Kx is a specific section included in the plurality of sections K.

Here, in order to explain an example of the processing, it is assumed that the image G1 (transmission image) corresponding to each of the sections K1, K2, and K3 in FIG. 2 is recorded on the recording device 210 on the day A. Further, it is assumed that the section Kx is, for example, the section K2. Further, it is assumed that the image transmission control process C and the display device side process C are performed again on the day B after the day A.

Further, the above-mentioned standard high quality is a quality corresponding to a high bit rate (for example, a line) which is a bit rate higher than the bit rate of the image G1 (transmission image) recorded in the recording device 210 and corresponding to the section Kx. It is assumed that the quality is q3). Further, on day B, it is assumed that the line quality determination process corresponding to the section Kx is performed, the measurement line quality is determined to be higher than the standard quality (standard high quality), and the high bit rate image request processing is performed. do. That is, it is assumed that the measurement line quality is higher than the standard quality (standard high quality).

In this case, in the high bit rate image request process, the image display device 200 requests the wireless image transmission system 100 for a high bit rate image associated with the section Kx. The high bit rate image associated with the section Kx is an image having a high bit rate recorded in the recording device 210, which is a bit rate higher than the bit rate of the image G1 (transmission image) corresponding to the section Kx. be. Further, the high bit rate image associated with the section Kx is an image showing the contents of the image G1 (transmission image) corresponding to the section Kx. The image quality of the high bit rate image associated with the section Kx is higher than that of the image G1 (transmission image) corresponding to the section Kx.

Specifically, in the high bit rate image request processing, the image display device 200 transmits an image request instruction to the wireless image transmission system 100. The image request instruction is an instruction for requesting a high bit rate image associated with the section Kx recorded in the image processing unit 130.

When the wireless image transmission system 100 receives an image request instruction, the wireless image transmission system 100 performs an image retransmission process. In the image retransmission processing, the wireless communication unit 150 of the wireless image transmission system 100 displays a high bit rate image associated with the section Kx recorded in the image processing unit 130 via the wireless line N1. Transmit to 200. In the following, an image for recording in the recording device 210 is also referred to as a “recorded image”.

As a result, in the display device side process C, the image display device 200 receives the high bit rate image associated with the section Kx as a recorded image. Further, in the display device side process C, the recorded image update process is performed. In the recorded image update process, the image display device 200 updates the image G1 (transmission image) corresponding to the section Kx recorded in the recording device 210 to a high bit rate image associated with the received section Kx. Perform processing.

(summary)
As described above, according to the present modification, it is possible to obtain an effect that a high-quality high-bit rate image can be recorded on the recording device 210 while continuously transmitting a normal image to the image display device 200.

The configuration described above is not limited to the configuration in which the configuration of this modification is applied to the modification 2. The configuration of this modification may be applied to the first embodiment or the first modification.

(Functional block diagram)
FIG. 6 is a block diagram showing a characteristic functional configuration of the wireless image transmission system BL10. FIG. 6 shows the wireless line N1 and the image display device 200 for the sake of explanation. The wireless image transmission system BL10 corresponds to the wireless image transmission system 100. That is, FIG. 6 is a block diagram showing the main functions related to the present technology among the functions of the wireless image transmission system BL10.

The wireless image transmission system BL10 transmits an image to the external image display device 200 via the wireless line N1. The wireless image transmission system BL10 is mounted on a train traveling on a predetermined route. There are a plurality of sections in the route.

Each of the sections is associated with a transmission image bit rate, which is the bit rate of the image for transmitting an image from the section to the image display device 200.

The wireless image transmission system BL10 functionally includes a position specifying unit BL1, an image processing unit BL2, and a wireless communication unit BL3. The position specifying unit BL1 identifies any of the plurality of sections as a traveling position which is the position of the train traveling on the route. The position specifying unit BL1 corresponds to the position specifying unit 110. The plurality of sections include a traveling section which is a section specified as the traveling position.

The image processing unit BL2 generates a transmission image which is an image having the transmission image bit rate associated with the traveling section. The image processing unit BL2 corresponds to the image processing unit 130. The wireless communication unit BL3 transmits the generated transmission image to the image display device 200 via the wireless line N1. The wireless communication unit BL3 corresponds to the wireless communication unit 150.

(Other variants)
The wireless image transmission system and the image display system according to the present technology have been described above based on the embodiments, but the present technology is not limited to the embodiments. The present technology also includes modifications that can be conceived by those skilled in the art to the extent that they do not deviate from the gist of the present technology. That is, in the present technology, the embodiments and the modified examples can be freely combined, and the embodiments and the modified examples can be appropriately modified or omitted.

For example, the wireless image transmission system 100 may not include all the components shown in the figure. That is, the wireless image transmission system 100 may include only the minimum components that can realize the effect of the present technology.

Further, each function of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 included in the wireless image transmission system 100 may be realized by a processing circuit.

The processing circuit is a circuit for specifying any one of the plurality of sections as a traveling position which is a position of the train traveling on the route.

Further, the processing circuit is also a circuit for generating a transmission image, which is an image having the transmission image bit rate associated with the traveling section.

The processing circuit is also a circuit for transmitting the generated transmission image to the image display device via the wireless line.

The processing circuit may be dedicated hardware. Further, the processing circuit may be a processor that executes a program stored in the memory. The processor is, for example, a CPU (Central Processing Unit), a central processing unit, an arithmetic unit, a microprocessor, a microcomputer, a DSP (Digital Signal Processor), or the like.

In the following, a configuration in which the processing circuit is dedicated hardware is also referred to as “configuration Cs1”. Further, in the following, the configuration in which the processing circuit is a processor is also referred to as “configuration Cs2”. Further, in the following, a configuration in which each function of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 is realized by a combination of hardware and software is also referred to as “configuration Cs3”.

In configuration Cs1, the processing circuit is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. Applicable to The functions of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 may be realized by three processing circuits, respectively. Further, all the functions of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 may be realized by one processing circuit.

In addition, the configuration in which all or a part of each component included in the wireless image transmission system 100 is shown by hardware is as follows, for example. In the following, a wireless image transmission system in which all or a part of each component included in the wireless image transmission system 100 is shown by hardware is also referred to as a “wireless image transmission system hd10”.

FIG. 7 is a hardware configuration diagram of the wireless image transmission system hd10. With reference to FIG. 7, the wireless image transmission system hd10 includes a processor hd1 and a memory hd2. The memory hd2 is a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM, or an EEPROM. The memory hd2 is, for example, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD, or the like. Further, the memory hd2 may be any storage medium used in the future.

In the configuration Cs2, the processing circuit is the processor hd1. In the configuration Cs2, each function of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 is realized by software, firmware, or a combination of software and firmware. The software or firmware is described as a program and stored in the memory hd2.

Further, in the configuration Cs2, the processing circuit (processor hd1) reads the program stored in the memory hd2 and executes the program, so that each of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 is executed. The function is realized. That is, the memory hd2 stores the following programs.

The program is a program for causing a processing circuit (processor hd1) to execute a step of specifying any one of the plurality of sections as a traveling position which is a position of the train traveling on the route.

The program is also a program for causing the processing circuit (processor hd1) to execute a step of generating a transmission image, which is an image having the transmission image bit rate associated with the traveling section.

The program is also a program for causing the processing circuit (processor hd1) to execute a step of transmitting the generated transmission image to the image display device via the wireless line.

Further, the program also causes a computer to execute a procedure of processing performed by each of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150, a method of executing the processing, and the like.

In the configuration Cs3, some functions of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 are realized by dedicated hardware. Further, in the configuration Cs3, another part of the functions of the position specifying unit 110, the image processing unit 130, and the wireless communication unit 150 are realized by software or firmware.

For example, the functions of the position specifying unit 110 and the image processing unit 130 are realized by the processing circuit reading and executing the program stored in the memory. Further, for example, the function of the wireless communication unit 150 is realized by a processing circuit as dedicated hardware.

Like the above configurations Cs1, configuration Cs2, and configuration Cs3, the processing circuit can realize each of the above-mentioned functions by hardware, software, firmware, or a combination thereof.

Further, the present technology may be realized as a wireless image transmission method in which the operation of a characteristic component included in the wireless image transmission system 100 is a step. Further, the present technology may be realized as a program for causing a computer to execute each step included in such a wireless image transmission method. Further, the present technology may be realized as a computer-readable recording medium for storing such a program. Further, the program may be distributed via a transmission medium such as the Internet. The wireless image transmission method according to the present technology corresponds to, for example, the processing of FIG.

All the numerical values used in the above-described embodiment and each modification are numerical values of an example for concretely explaining the present technology. That is, the present technology is not limited to the numerical values used in the above-described embodiment and each modification.

It is possible to freely combine the embodiments and the modified examples, and to appropriately modify or omit the embodiments and the modified examples.

For example, the number of sections K existing in the route Rt may be any of 2, 3 and 4 or more.

Further, for example, the position specifying unit 110, the image quality adjusting unit 120, the image processing unit 130, and the wireless communication unit 150 included in the wireless image transmission system 100 may be configured by one processor.

100, BL10, hd10 wireless image transmission system, 110, BL1 position identification unit, 120 image quality adjustment unit, 130, BL2 image processing unit, 140 camera, 150, BL3 wireless communication unit, 200 image display device, 210 recording device, 1000 images Display system, MV1 train.

Claims (7)

A wireless image transmission system that transmits images to an external image display device via a wireless line.
The wireless image transmission system is mounted on a train traveling on a predetermined route.
There are multiple sections in the route,
Each of the sections is associated with a transmission image bit rate, which is the bit rate of the image for transmitting an image from the section to the image display device.
The wireless image transmission system is
A position specifying unit for specifying any of the plurality of sections as a traveling position which is a position of the train traveling on the route is provided.
The plurality of sections include a traveling section which is a section specified as the traveling position.
The wireless image transmission system further includes
An image processing unit that generates a transmission image, which is an image having the transmission image bit rate associated with the traveling section, and an image processing unit.
It includes a wireless communication unit that transmits the generated transmission image to the image display device via the wireless line.
Wireless image transmission system. The wireless image transmission system further includes
Equipped with a camera that has a function to shoot
The image processing unit generates the transmission image by using the image obtained by the camera taking a picture.
The wireless image transmission system according to claim 1. The wireless image transmission system has a database and has a database.
The database shows the traveling section in association with the transmitted image bit rate corresponding to the traveling section.
The wireless communication unit measures the line quality, which is the quality of the wireless line corresponding to the traveling section, and measures the line quality.
The radio image transmission system changes the transmission image bit rate associated with the travel section indicated by the database to an image bit rate corresponding to the measured line quality, thereby displaying the transmitted image. Update the bit rate and the relevant image,
The wireless image transmission system according to claim 1 or 2. An image display system including the wireless image transmission system and the image display device according to claim 1 or 2.
The wireless image transmission system has a database and has a database.
The database shows the traveling section in association with the transmitted image bit rate corresponding to the traveling section.
The image display device transmits an instruction for changing the transmission image bit rate associated with the traveling section based on the reception state of the transmission image transmitted from the wireless communication unit. Send to system
The wireless image transmission system updates the database by changing the transmission image bit rate associated with the travel section, which is indicated by the database, based on the instructions.
Image display system. The wireless image transmission system notifies the image display device of the traveling section, the bit rate of the transmission image, and the line quality which is the quality of the wireless line corresponding to the traveling section.
The image display device transmits the instruction to the wireless image transmission system in response to the notification.
The image display system according to claim 4. An image display system including the wireless image transmission system and the image display device according to any one of claims 1 to 5.
The image display system further
Equipped with a recording device that has the function of storing images
The wireless image transmission system performs an image transmission process of transmitting the transmission image to the image display device via the wireless line in each section.
During the period when the image display device receives the transmission image,
(A1) The image display device displays the transmission image corresponding to the quality of the wireless line as a live image.
(A2) The image display device performs a recording process of recording the transmission image in the recording device.
By repeating the recording process, the transmission image corresponding to each of the plurality of sections is recorded in the recording device.
The quality of the radio line is a quality corresponding to a high bit rate recorded in the recording device, which is a bit rate higher than the bit rate of the transmission image corresponding to the specific section included in the plurality of sections. case,
(B1) The image display device converts a high bit rate image, which is an image having the high bit rate and is an image showing the content of the transmission image corresponding to the specific section, into the wireless image transmission system. Request and
(B2) The image display device receives the high bit rate image as a recorded image for recording in the recording device.
Image display system. A wireless image transmission method performed by a wireless image transmission system that transmits an image to an external image display device via a wireless line.
The wireless image transmission system is mounted on a train traveling on a predetermined route.
There are multiple sections in the route,
Each of the sections is associated with a transmission image bit rate, which is the bit rate of the image for transmitting an image from the section to the image display device.
The wireless image transmission method is
A step of specifying any of the plurality of sections as a traveling position which is a position of the train traveling on the route is provided.
The plurality of sections include a traveling section which is a section specified as the traveling position.
The wireless image transmission method further comprises
A step of generating a transmission image, which is an image having the transmission image bit rate associated with the travel section,
A step of transmitting the generated transmission image to the image display device via the wireless line is provided.
Wireless image transmission method.

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