Image transmission system

Abstract

This invention provides an image transmission system capable of reliably establishing communication between communication devices for reverse channel communication. The encoder includes: a first transmitting unit that transmits a specific signal for communication establishment to a decoder via a first communication line during the blanking period of image data; and a determining unit that, upon receiving a command signal indicating communication establishment from the decoder via a second communication line after transmitting the specific signal, determines the establishment of reverse channel communication. The decoder includes: a determining unit that determines whether the signal received from the encoder during the blanking period is the specific signal; and a second transmitting unit that, if the received signal is the specific signal, transmits a command signal to the encoder via the second communication line. The encoder and decoder perform reverse channel communication via the second communication line after determining the establishment of communication.

Description

Technical Field

[0001] This disclosure relates to an image transmission system for transmitting image data between an encoder and a decoder. Background Technology

[0002] Recently, image transmission systems have been used in vehicles and the like, in which images captured by a camera are transmitted from one communication device to another via a communication line in the form of image data obtained by serial data conversion. (Patent Document 1) In previous image transmission systems, typically one communication device included an encoder for serial data conversion, and the other communication device included a decoder for parallel data conversion.

[0003] [Existing Technical Documents]

[0004] [Patent Literature]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 2024-093153 Summary of the Invention

[0006] In previous image transmission systems, image data transmission was a one-way communication from one communication device to another. Therefore, in order to enable data transmission from one communication device to another to achieve data communication other than image data, a back channel communication was used. Through back channel communication, for example, it is possible to change the communication mode of image data from one communication device to another or to change the shooting mode of a camera.

[0007] However, if the communication between communication devices used for reverse channel communication is not established correctly, the following problems may occur: malfunctions or failures may occur during data transmission in reverse channel communication.

[0008] Therefore, the purpose of this disclosure is to provide an image transmission system that can reliably establish communication between communication devices for reverse channel communication.

[0009] The image data transmission system disclosed herein is an image transmission system that transmits image data from an encoder to a decoder via a first communication line. The encoder includes: a first transmitting unit that transmits a specific signal for establishing communication to the decoder via the first communication line during the blanking period of the image data; and a determining unit that, upon receiving a command signal indicating communication establishment from the decoder via a second communication line after transmitting the specific signal, determines the establishment of reverse channel communication. The decoder includes: a determining unit that determines whether a signal received from the encoder during the blanking period is the specific signal; and a second transmitting unit that, upon receiving a signal that is the specific signal, transmits the command signal to the encoder via the second communication line. The encoder and the decoder perform the reverse channel communication via the second communication line after determining the establishment of the reverse channel communication.

[0010] The image data transmission system disclosed herein is an image transmission system that transmits image data from an encoder to a decoder via a first communication line, and includes a control unit connected to the decoder. When a specific signal detection notification is received, the control unit sends a communication establishment request to the decoder. The encoder includes: a first transmitting unit that transmits a specific signal for communication establishment to the decoder via the first communication line during the blanking period of the image data; and a determining unit that, upon receiving a command signal indicating communication establishment from the decoder via a second communication line after transmitting the specific signal, determines the establishment of reverse channel communication. The decoder includes: a determining unit that determines whether a signal received from the encoder during the blanking period is the specific signal; a notification unit that, if the received signal is the specific signal, supplies the specific signal detection notification to the control unit; and a second transmitting unit that, according to the communication establishment request, transmits the command signal to the encoder via the second communication line. After determining the establishment of reverse channel communication, the encoder and the decoder perform the reverse channel communication via the second communication line. Attached Figure Description

[0011] Figure 1 This is a block diagram representing the image transmission system of this disclosure.

[0012] Figure 2 It means Figure 1 The sequence diagram of communication establishment actions in the reverse channel communication of the system.

[0013] Figure 3 (a) ~ Figure 3 (c) represents Figure 1 A diagram illustrating the successful communication establishment process of reverse channel communication in the system.

[0014] Figure 4 (a) ~ Figure 4 (c) represents Figure 1 A diagram illustrating the failure modes of communication establishment actions in the reverse channel communication of the system.

[0015] Figure 5 (a) ~ Figure 5 (c) represents Figure 1 A diagram illustrating the failure modes of communication establishment actions in the reverse channel communication of the system.

[0016] Explanation of icon numbers

[0017] 11: Encoder

[0018] 12: Decoder

[0019] 13: MCU

[0020] 21: Image Source

[0021] 22, 61: Receiving and Dispatch Department

[0022] 23, 62: Status Management Department

[0023] 31: Image Data Transmission Department

[0024] 32: Specific signal transmitting unit

[0025] 33: Command signal receiving unit

[0026] 34: ACK signal transmitting unit

[0027] 41, 42: Communication lines

[0028] 43: Data cable

[0029] 51: Specific signal generation unit

[0030] 52: Command Signal Determination Unit

[0031] 53: ACK signal generation unit

[0032] 63: Image Output Section

[0033] 71: Image Data Receiving Unit

[0034] 72: Specific signal receiving unit

[0035] 73: Command Signal Transmitting Unit

[0036] 74: ACK signal receiving unit

[0037] 81: Specific Signal Determination Unit

[0038] 82: Command Signal Generation Unit

[0039] 83: Communication Establishment Confirmation Department

[0040] S11, S12, S13, S14, S15, S16, S17, S18, S19, S20, S21, S22, S23, S24, S25, S26, S27, S28, S29: Steps Detailed Implementation

[0041] The following is a reference to the appendix. Figure 1 The image transmission system disclosed herein will be described in detail below.

[0042] [Example]

[0043] Figure 1 The image transmission system of this disclosure is illustrated. The image transmission system includes an encoder 11, a decoder 12, and a microcontroller unit (MCU) 13 as communication devices. The encoder 11 and decoder 12 are interconnected via communication lines 41 and 42. The decoder 12 and MCU 13 are interconnected via data line 43.

[0044] The encoder 11 includes an image source 21, a transceiver unit 22, and a status management unit 23. The image source 21 is, for example, a camera, and generates image signals as parallel data. The transceiver unit 22 is connected to the image source 21 and performs data communication containing image data with the decoder 12. The transceiver unit 22 includes an image data transmission unit 31, a specific signal transmission unit 32, a command signal reception unit 33, and an ACK (acknowledgment) signal transmission unit 34. A communication line 41 is connected to the image data transmission unit 31 and the specific signal transmission unit 32, and a communication line 42 is connected to the command signal reception unit 33 and the ACK signal transmission unit 34. The communication line 41 is a first communication line and is a unidirectional communication line. The communication line 42 is a second communication line for reverse channel communication and is a bidirectional communication line. Reverse channel communication is communication from the decoder 12 to the encoder 11.

[0045] The image data transmission unit 31 converts the image signal supplied from the image source 21 into image data as serial data and transmits the image data to the decoder 12 via the communication line 41. The specific signal transmission unit 32 inserts a specific signal supplied from the status management unit 23 into the blanking period of the image data and transmits it to the decoder 12 via the communication line 41. The blanking period is the portion of the image data excluding the image portion and the vertical and horizontal synchronization signal portions, and is the period during which the image is not displayed on the screen. The specific signal is a signal indicating the start of reverse channel communication. The command signal receiving unit 33 receives a command signal transmitted from the decoder 12 via the communication line 42. The command signal is a signal generated by the MCU 13. The ACK signal transmission unit 34 transmits an ACK signal supplied from the status management unit 23 to the decoder 12 via the communication line 42.

[0046] The status management unit 23 is the part that manages the operational status of the transceiver unit 22. The status management unit 23 includes a specific signal generation unit 51, a command signal determination unit 52, and an ACK signal generation unit 53.

[0047] A specific signal generation unit 51 generates a specific signal and supplies the specific signal to a specific signal transmission unit 32. The generation of the specific signal by the specific signal generation unit 51 can be performed, for example, based on an external input operation, or it can be performed automatically at predetermined time intervals. The specific signal contains a predetermined code string, such as ABCD. A command signal determination unit 52 receives a command signal received by a command signal receiving unit 33 and determines whether the command signal is a specified command signal. An ACK signal generation unit 53 generates an ACK signal based on the determination result of the command signal determination unit 52. That is, if it is determined that the received command signal is a specified command signal, an ACK signal is generated. The ACK signal generation unit 53 supplies the generated ACK signal to an ACK signal transmission unit 34.

[0048] The decoder 12 includes a transceiver unit 61, a status management unit 62, and an image output unit 63. The transceiver unit 61 includes an image data receiving unit 71, a specific signal receiving unit 72, a command signal transmitting unit 73, and an ACK signal receiving unit 74. Communication line 41 is connected to the image data receiving unit 71 and the specific signal receiving unit 72, and communication line 42 is connected to the command signal transmitting unit 73 and the ACK signal receiving unit 74.

[0049] Image data receiving unit 71 receives image data transmitted from encoder 11 via communication line 41. Specific signal receiving unit 72 receives specific signals transmitted from encoder 11 via communication line 41. Command signal transmitting unit 73 transmits command signals supplied from status management unit 62 to encoder 11 via communication line 42. ACK signal receiving unit 74 receives ACK signals transmitted from encoder 11 via communication line 42.

[0050] The status management unit 62 is the part that manages the operational status of the transceiver unit 61. The status management unit 62 includes a specific signal determination unit 81, a command signal generation unit 82, and a communication establishment confirmation unit 83.

[0051] The specific signal determination unit 81 receives a specific signal received by the specific signal receiving unit 72 and determines whether the specific signal represents a predetermined code string. The determination result of the specific signal determination unit 81 is supplied to the MCU 13 via the data line 43. The command signal generation unit 82 is connected to the MCU 13 via the data line 43 and generates a command signal representing a predetermined communication establishment based on a communication establishment request from the MCU 13. Here, the communication establishment refers to the establishment of a connection for reverse channel communication using the communication line 42 between the encoder 11 and the decoder 12. The command signal generation unit 82 supplies the generated command signal to the command signal transmission unit 73. The communication establishment confirmation unit 83 receives an ACK signal received by the ACK signal receiving unit 74 and confirms the communication establishment between the encoder 11 and the decoder 12 via the communication line 42 based on the ACK signal.

[0052] The image output unit 63 is connected to the transceiver unit 61 and supplies image data received by the image data receiving unit 71 to the image output unit 63. For example, the image output unit 63 is a display that shows the image represented by the supplied image data or a storage device that stores the image data.

[0053] The MCU 13 is the master device and is connected to the decoder 12 via data line 43 as described above. The MCU 13 can receive the determination result of a predetermined code string representing a specific signal from the specific signal determination unit 81 in the form of a specific signal detection notification via data line 43. Upon receiving a specific signal detection notification, the MCU 13 supplies a communication establishment request to the command signal generation unit 82 via data line 43. The communication establishment request can be generated only when reverse channel communication is required. Furthermore, when the communication establishment confirmation unit 83 confirms the establishment of reverse channel communication, the MCU 13 receives a communication establishment notification from the communication establishment confirmation unit 83 via data line 43.

[0054] The reverse channel communication, as described above, is communication via communication line 42. In this embodiment, it is serial communication using the Inter-Integrated Circuit (I2C) communication method. In I2C communication, communication line 42 includes signal lines for data and signal lines for clock. Furthermore, although not shown, the transceiver unit 22 of encoder 11 and the transceiver unit 61 of decoder 12 each include transceiver units for data communication using the I2C communication method.

[0055] Next, use Figure 2 The sequence diagram illustrates the communication establishment action of the reverse channel communication in the image transmission system of the aforementioned structure.

[0056] In encoder 11, for example, specific signal generation unit 51 generates a specific signal according to an instruction from the outside (step S11), and transmits the specific signal from specific signal transmission unit 32 to decoder 12 via communication line 41 (step S12). The specific signal is superimposed on the blanking period of the image data during transmission.

[0057] In decoder 12, specific signal receiving unit 72 extracts signals other than image data during the blanking period of image data arriving via communication line 41, thereby receiving a signal (step S13). The received signal is supplied to specific signal determination unit 81. In specific signal determination unit 81, it is determined whether the received signal represents a specific signal containing a predetermined code string (step S14). If the received signal represents a specific signal containing a predetermined code string, the determination result is supplied to MCU 13 via data line 43 in the form of a specific signal detection notification (step S15).

[0058] In MCU 13, when a specific signal detection notification is received (step S16), a communication establishment request is generated and the communication establishment request is supplied to the command signal generation unit 82 via data line 43 (step S17).

[0059] In the command signal generation unit 82, when a communication establishment request is received from the MCU 13 (step S18), a command signal indicating communication establishment is generated according to the communication establishment request, and the command signal is supplied to the command signal transmission unit 73 (step S19). In the command signal transmission unit 73, the command signal is transmitted to the encoder 11 via the communication line 42 (step S20). The transmission of the command signal via the communication line 42 can also be performed during the blanking period of the image data.

[0060] In encoder 11, command signal receiving unit 33 receives the command signal sent in step S20 (step S21). The received command signal is supplied to command signal determination unit 52, where it is determined whether it is a specified command signal (step S22). If the received command signal is a specified command signal, ACK signal generation unit 53 generates an ACK signal (step S23). The generated ACK signal is supplied to ACK signal transmitting unit 34, and transmitted to decoder 12 via communication line 42 (step S24).

[0061] In decoder 12, ACK signal receiving unit 74 receives the ACK signal sent in step S24 (step S25). The received ACK signal is supplied to communication establishment confirmation unit 83, which confirms the establishment of reverse channel communication based on the reception of the ACK signal (step S26). When communication establishment is confirmed in step S26, a communication establishment notification is sent to MCU 13 via data line 43 (step S27).

[0062] Furthermore, when the establishment of reverse channel communication is confirmed, in addition to transmitting image data from encoder 11 to decoder 12, reverse channel communication from decoder 12 to encoder 11 can also be performed (step S28). When a communication establishment notification is received (step S29), MCU 13 can control the transmission of data from decoder 12 to encoder 11 while reverse channel communication between encoder 11 and decoder 12 is possible. Additionally, MCU 13 can instruct the transmission and reception of data used for setting the operation of encoder 11 and connected devices. Examples include writing / reading registers within encoder 11, controlling the Serial Peripheral Interface (SPI) flash memory connected to encoder 11, and I2C writing / reading of other devices connected to the I2C bus of encoder 11.

[0063] As described above, a predetermined code string for a specific signal is transmitted by the specific signal transmitting unit 32 of the encoder 11 to be configured during the blanking period of the image data. The predetermined code string for the specific signal is configured during the blanking period of any or a specified single line of the image data, or distributed across the blanking periods of multiple specified lines within one frame of image data. For example, in the case of the code string "ABCD", such as... Figure 3 As shown in (a), the image data is configured with "A" at line number 1, "B" at line number 2, "C" at line number 3, and "D" at line number 4 in a distributed configuration. Furthermore, within a single frame of the image data, the code string "ABCD" only needs to be sequentially configured on any one or more lines.

[0064] In decoder 12, the signal received by specific signal receiving unit 72 is Figure 3 In the case of “ABCD” in (a), regarding the expected value of receiving the pre-defined code string, such as Figure 3 As shown in (b), when "ABCD" exists in the specific signal determination unit 81, the specific signal determination unit 81 performs a consistency determination and generates a specific signal detection notification. Therefore, the MCU 13 generates a communication establishment request, as follows: Figure 3As shown in (b), the command signal generation unit 82 generates a command signal containing the fixed value "1234" and sends the command signal from the command signal transmission unit 73.

[0065] In encoder 11, such as Figure 3 As shown in (c), when a command signal containing the fixed value "1234" is received, the command signal determination unit 52 determines that it is a specified command signal and confirms the establishment of communication. As a result, reverse channel communication can be performed using the communication line 42.

[0066] On the other hand, in decoder 12, even if the signal received by a specific signal receiving unit 72 is Figure 4 In the case of “ABCD” in (a), regarding the expected value of receiving the pre-defined code string, such as Figure 4 As shown in (b), if "ABCD" does not exist in the specific signal determination unit 81, a specific signal detection notification is not generated, and therefore a command signal cannot be generated. Figure 4 As shown in (c), no communication is established.

[0067] like Figure 5 As shown in (a), when a specific signal is not inserted into the blanking period of the image data in encoder 11, the expected value of the received signal as a predetermined code string is as follows: Figure 5 As shown in (b), even if "ABCD" exists in the specific signal determination unit 81, the specific signal determination unit 81 cannot identify the specific signal due to consistency determination. Similarly, in this case, no specific signal detection notification is generated, and therefore no command signal can be generated, such as... Figure 5 As shown in (c), no communication is established.

[0068] Without establishing communication as described above, it is impossible to continue transmitting image data from encoder 11 to decoder 12 without performing reverse channel communication.

[0069] The image transmission system disclosed herein can reliably perform communication establishment in reverse channel communication, and start data transmission based on reverse channel communication after the communication establishment is confirmed, thus preventing malfunctions or failures during reverse channel communication.

[0070] Furthermore, the image transmission system of this embodiment includes an MCU 13, which is not essential to the image transmission system. When receiving and determining specific signals sent from the encoder 11, the decoder 12 may send a command signal to the encoder 11 without sending a specific signal detection notification to the MCU 13.

[0071] This disclosure is not limited to the form of the described embodiments, and various modifications and design changes can be made without departing from the spirit of this disclosure.

[0072] [Postscript]

[0073] The following structure is disclosed in this specification.

[0074] (Structure 1)

[0075] An image transmission system transmits image data from an encoder to a decoder via a first communication line. In the image transmission system, the encoder includes: a first transmitting unit that transmits a specific signal for establishing communication to the decoder via the first communication line during a blanking period of the image data; and a determining unit that, upon receiving a command signal indicating communication establishment from the decoder via a second communication line after transmitting the specific signal, determines the establishment of reverse channel communication. The decoder includes: a determining unit that determines whether a signal received from the encoder during the blanking period is the specific signal; and a second transmitting unit that, if the received signal is the specific signal, transmits the command signal to the encoder via the second communication line. The encoder and the decoder perform reverse channel communication via the second communication line after determining the establishment of reverse channel communication.

[0076] (Structure 2)

[0077] According to the image transmission system of Structure 1, the specific signal contains a predetermined code string.

[0078] (Structure 3)

[0079] According to the image transmission system of structure 2, the code string is distributed across multiple lines in the image data of one frame.

[0080] (Structure 4)

[0081] According to the image transmission system of structure 1, bidirectional communication is possible in the second communication line.

[0082] (Structure 5)

[0083] According to the image transmission system of structure 1, when performing the reverse channel communication, data is sent from the decoder to the encoder via the second communication line.

[0084] (Structure 6)

[0085] The image transmission system according to any one of structures 1 to 5, wherein the second communication line is a communication line for I2C communication.

[0086] (Structure 7)

[0087] According to any one of structures 1 to 5, in the image transmission system, the second transmitting unit transmits the command signal during the blanking period.

[0088] (Structure 8)

[0089] An image transmission system transmits image data from an encoder to a decoder via a first communication line. The image transmission system includes a control unit connected to the decoder. Upon receiving a specific signal detection notification, the control unit sends a communication establishment request to the decoder. The encoder includes: a first transmitting unit that transmits a specific signal for communication establishment to the decoder via the first communication line during a blanking period of the image data; and a determining unit that, upon receiving a command signal indicating communication establishment from the decoder via a second communication line after transmitting the specific signal, determines the establishment of reverse channel communication. The decoder includes: a determining unit that determines whether a signal received from the encoder during the blanking period is the specific signal; a notification unit that, if the received signal is the specific signal, supplies the specific signal detection notification to the control unit; and a second transmitting unit that, based on the communication establishment request, transmits the command signal to the encoder via the second communication line. After determining the establishment of reverse channel communication, the encoder and the decoder perform reverse channel communication via the second communication line.

Claims

1. An image transmission system that transmits image data from an encoder to a decoder via a first communication line, wherein in the image transmission system, The encoder has: The first transmitting unit transmits a specific signal for establishing communication to the decoder via the first communication line during the blanking period of the image data; and The decision unit, upon receiving a command signal indicating communication establishment from the decoder via the second communication line after sending the specific signal, determines the establishment of reverse channel communication. The decoder has: The determination unit determines whether the signal received from the encoder during the blanking period is the specific signal; and The second transmitting unit, when the received signal is the specific signal, transmits the command signal to the encoder via the second communication line. The encoder and the decoder perform the reverse channel communication via the second communication line after determining that the reverse channel communication has been established.

2. The image transmission system according to claim 1, wherein, The specific signal contains a predetermined code string.

3. The image transmission system according to claim 2, wherein, The code string is distributed across multiple lines in the image data of one frame.

4. The image transmission system according to claim 1, wherein, The second communication line enables bidirectional communication.

5. The image transmission system according to claim 1, wherein, During the reverse channel communication, data is sent from the decoder to the encoder via the second communication line.

6. The image transmission system according to any one of claims 1 to 5, wherein, The second communication line is a communication line used for internal integrated circuit communication.

7. The image transmission system according to any one of claims 1 to 5, wherein, The second transmitting unit transmits the command signal during the blanking period.

8. An image transmission system for transmitting image data from an encoder to a decoder via a first communication line, wherein the image transmission system includes a control unit. The control unit is connected to the decoder, and when it receives a specific signal detection notification, it sends a communication establishment request to the decoder. The encoder has: The first transmitting unit transmits a specific signal for establishing communication to the decoder via the first communication line during the blanking period of the image data; and The decision unit, upon receiving a command signal indicating communication establishment from the decoder via the second communication line after sending the specific signal, determines the establishment of reverse channel communication. The decoder has: The determination unit determines whether the signal received from the encoder during the blanking period is the specific signal; The notification unit, when the received signal is the specific signal, supplies the specific signal detection notification to the control unit; and The second transmitting unit, based on the communication establishment request, transmits the command signal to the encoder via the second communication line. The encoder and the decoder perform the reverse channel communication via the second communication line after determining that the reverse channel communication has been established.

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