WO2017000507A1 - 视频信号的切换电路和切换方法 - Google Patents

视频信号的切换电路和切换方法 Download PDF

Info

Publication number
WO2017000507A1
WO2017000507A1 PCT/CN2015/097194 CN2015097194W WO2017000507A1 WO 2017000507 A1 WO2017000507 A1 WO 2017000507A1 CN 2015097194 W CN2015097194 W CN 2015097194W WO 2017000507 A1 WO2017000507 A1 WO 2017000507A1
Authority
WO
WIPO (PCT)
Prior art keywords
cable
voltage value
video signal
resistor
circuit
Prior art date
Application number
PCT/CN2015/097194
Other languages
English (en)
French (fr)
Inventor
尹鹏
章欢
梁秋芳
Original Assignee
杭州海康威视数字技术股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 杭州海康威视数字技术股份有限公司 filed Critical 杭州海康威视数字技术股份有限公司
Priority to US15/740,416 priority Critical patent/US10194113B2/en
Priority to EP15897032.7A priority patent/EP3316569B1/en
Publication of WO2017000507A1 publication Critical patent/WO2017000507A1/zh

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/41—Structure of client; Structure of client peripherals
    • H04N21/422—Input-only peripherals, i.e. input devices connected to specially adapted client devices, e.g. global positioning system [GPS]
    • H04N21/42204—User interfaces specially adapted for controlling a client device through a remote control device; Remote control devices therefor
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/60—Control of cameras or camera modules
    • H04N23/66—Remote control of cameras or camera parts, e.g. by remote control devices
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/41—Structure of client; Structure of client peripherals
    • H04N21/414—Specialised client platforms, e.g. receiver in car or embedded in a mobile appliance
    • H04N21/4147—PVR [Personal Video Recorder]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/436—Interfacing a local distribution network, e.g. communicating with another STB or one or more peripheral devices inside the home
    • H04N21/4363—Adapting the video stream to a specific local network, e.g. a Bluetooth® network
    • H04N21/43632—Adapting the video stream to a specific local network, e.g. a Bluetooth® network involving a wired protocol, e.g. IEEE 1394
    • H04N21/43635—HDMI
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N3/00—Scanning details of television systems; Combination thereof with generation of supply voltages
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/222—Studio circuitry; Studio devices; Studio equipment
    • H04N5/262—Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
    • H04N5/268—Signal distribution or switching
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/44—Receiver circuitry for the reception of television signals according to analogue transmission standards
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00—Television systems
    • H04N7/01—Conversion of standards, e.g. involving analogue television standards or digital television standards processed at pixel level

Definitions

  • the present invention relates to the field of video surveillance technologies, and in particular, to a switching circuit and a switching method for a video signal.
  • the first method of switching the DIP switch, the TVI and CVBS output switching mode of this solution is selected by the DIP switch.
  • the DIP switch is generally on the PCB board inside the camera.
  • the corresponding BNC line is first used.
  • the cable is connected to the DVR (Digital Video Recorder), then the machine casing is opened, and the dial switch is turned to the corresponding position to realize the switching.
  • the disadvantage of the scheme is that the operation of opening the casing is troublesome, and the dial switch has a larger volume. , occupying a large PCB space, there is a certain interference in the structure, which is not conducive to user operation.
  • 1 is a schematic diagram of a method for switching a video signal in the prior art. As shown in FIG. 1, a dial switch installed in a camera is required to manually switch gear positions. In FIG. 1, the first cable is transmitted.
  • the composite video signal CVBS cable, the second cable is the video transmission interface output signal TVI cable.
  • the second method of cable splicing switching, the TVI and CVBS output switching mode of the solution is to connect two control lines led by the machine, and one signal is output by default, and another signal is output when lapped.
  • the shortcomings of the solution are: the cable is pulled out and the bareness is likely to cause static electricity and the like, and the cable twisting may cause mechanical fatigue, and it is also susceptible to loose contact by external force, which affects the use of the machine.
  • 2 is a schematic diagram of another method for switching a video signal in the prior art. As shown in FIG. 2, two straps 1 and a strap 2 are pulled out on one side of the camera, and the straps are connected by selection. On the DVR, the TVI and CVBS signal lines are connected to the DVR to achieve signal switching.
  • the first cable is the cable for transmitting the composite video signal CVBS
  • the second cable is the cable for the video transmission interface output signal TVI.
  • the embodiment of the invention provides a switching circuit and a switching method for a video signal, so as to at least solve the technical problem that the adaptive switching of the video signal cannot be realized due to the need to manually switch the signal gear position in the prior art.
  • a switching circuit for a video signal including: an adjustment circuit, connected to a first cable, for adjusting the first cable to be in a pull-up state or in a released state, wherein The first cable is a cable for transmitting a composite video signal; the detecting circuit is connected to the first cable, and is configured to detect the first cable on the first cable in a state of the pull-up state a voltage value, or a second voltage value on the first cable in a case where the first cable is in the released state; a controller for determining the first voltage value from the detecting circuit or the a change in the second voltage value, wherein, in a case where it is determined that the second voltage value becomes large, the controller controls the second cable to transmit a video signal, or determines that the first voltage value becomes small Next, the controller controls the first cable to transmit a video signal, and the second cable is a cable that transmits a video transmission interface output signal.
  • the adjustment circuit includes: a first resistor, a first end of the first resistor is connected to a high level; a second resistor, a first end of the second resistor and an output end of the first input signal Connected to the second end of the second resistor, wherein the first input signal is a pin output signal of the controller; a triode, the triode a base is connected to the second end of the first resistor, a collector of the transistor is connected to a high level; a third resistor, a first end of the third resistor and an input end of the first cable Connected to, the second end of the third resistor is connected to the emitter of the transistor; the first capacitor, the first end of the first capacitor is connected to the second end of the first resistor, The second end of the first capacitor is connected to the ground.
  • the switching circuit further includes: a filter circuit, and the adjusting circuit and the detecting circuit are both connected to be used for controlling the second cable to transmit the video signal to the second voltage value A filtering process is performed, wherein the detecting circuit samples the filtered second voltage value.
  • the filter circuit includes: a fourth resistor, a first end of the fourth resistor is connected to an input end of the first cable; a second capacitor, a first end of the second capacitor is The second end of the fourth resistor is connected, and the second end of the second capacitor is connected to the ground.
  • the switching circuit further includes: an AD sampling port of the controller, wherein the AD sampling port is connected to the second end of the fourth resistor.
  • the switching circuit further includes: a serial port configuration circuit, which is connected to the controller through an asynchronous transceiver, wherein the controller controls the first cable to transmit the video signal through the serial port configuration circuit Or the second cable transmits the video signal.
  • the switching circuit further includes: a fifth resistor, the first end of the fifth resistor and the first The input ends of the cables are connected, and the second ends of the fifth resistors are connected to the ground terminals.
  • a method for switching a video signal including: adjusting a first cable in a pull-up state or in a released state, wherein the first cable is a cable for transmitting a composite video signal Detecting a first voltage value on the first cable in the case where the first cable is in the pulled-up state, or detecting a second voltage on the first cable in a case where the first cable is in the released state a voltage value; determining a change in the first voltage value or the second voltage value; transmitting a video signal through the first cable in a case where it is determined that the first voltage value is small; In the case where the second voltage value becomes large, the video signal is transmitted through the second cable, wherein the second cable is a cable that transmits a video transmission interface output signal.
  • the method further includes: filtering the second voltage value.
  • the method further includes: adjusting the first cable to be in the released state.
  • the first cable is in a pull-up state by controlling an output low level of the first input signal, wherein the first input signal is a pin output signal of the controller; by controlling the first input The output of the signal is high, causing the first cable to be in a released state.
  • the adjusting circuit is connected to the first cable for adjusting whether the first cable is in a pulled-up state or in a released state, wherein the first cable is a cable for transmitting a composite video signal;
  • the detecting circuit is The first cable is connected to detect a first voltage value on the first cable when the first cable is in the pulled-up state, or to detect a second voltage value on the first cable when the first cable is in the released state;
  • the controller And determining a change of the first voltage value or the second voltage value from the detecting circuit, wherein, when it is determined that the second voltage value becomes large, the controller controls the second cable to transmit the video signal, or determines the first In the case where a voltage value becomes small, the controller controls a manner in which the first cable transmits a video signal, and the second cable is a cable that transmits a signal output from the video transmission interface.
  • Adjusting the circuit to adjust the first cable to be in a pulled-up state or in a released state wherein the adjusting circuit is connected to the first cable, and in the case that the first cable is in the pulled-up state, detecting the first voltage on the first cable The value determines whether the first voltage value becomes smaller. If the first voltage value does not change, the second cable continues to control the transmission of the video signal, and the adjustment circuit adjusts the first cable to be in a released state. In the case where the first cable is in the released state, the second voltage value on the first cable is detected, and when it is detected that the second voltage value becomes large, the controller controls the second cable to transmit the video signal. At the same time, the adjusting circuit adjusts the first cable to be in a pull-up state.
  • the first cable is continuously controlled to transmit a video signal, wherein the detecting circuit is also connected to the first cable, so that it is not necessary to manually switch the gear position.
  • the purpose of the video signal switching is realized, thereby realizing the technical effect of adaptively switching the video signal, thereby solving the technical problem that the adaptive switching of the video signal cannot be realized due to the manual switching of the signal gear position in the prior art.
  • FIG. 1 is a schematic diagram of a method for switching a video signal according to the prior art
  • FIG. 2 is a schematic diagram of another method for switching a video signal according to the prior art
  • FIG. 3 is a schematic diagram of an optional switching circuit of a video signal according to an embodiment of the present invention.
  • FIG. 4 is a schematic diagram of another optional switching circuit of a video signal according to an embodiment of the present invention.
  • FIG. 5 is a schematic diagram of another optional switching circuit of a video signal according to an embodiment of the present invention.
  • FIG. 6 is a schematic diagram of another optional switching circuit of a video signal according to an embodiment of the present invention.
  • FIG. 7 is a schematic diagram of an equivalent circuit for controlling a first cable to transmit a video signal without a connection to a load, in accordance with an embodiment of the present invention
  • FIG. 8 is a schematic diagram of an equivalent circuit for controlling a first cable to transmit a video signal in a case where a switching circuit of a video signal is connected to a load according to an embodiment of the present invention
  • FIG. 9 is a schematic diagram of an equivalent circuit for controlling a second cable to transmit a video signal in a case where a switching circuit of a video signal is connected to a load according to an embodiment of the present invention
  • FIG. 10 is a schematic diagram of an equivalent circuit for transmitting a video signal of a second cable in a case where a switching circuit of a video signal is not connected to a load according to an embodiment of the present invention
  • FIG. 11 is a flow chart of an alternative method of switching video signals according to an embodiment of the present invention.
  • HD-TVI (Hight Definition-Transport Video Interface) is a high-definition video transmission specification based on coaxial cable. It refers to the output signal of high-definition video transmission interface.
  • CVBS Composite Video Broadcast Signal or Composite Video Blanking and Sync
  • a composite video signal that includes a luminance signal, a chrominance signal, and a synchronization signal (including a field sync, a line sync signal, and a line blanking signal).
  • the processing method is automatically adjusted according to the characteristics of the processed data to adapt it to external requirements.
  • BNC cable (Bayonet Nut Connector) coaxial cable with connector.
  • UART Universal Asynchronous Receiver/Transmitter is an asynchronous transceiver.
  • BT.1120 is a digital high definition video data format protocol, which represents digital data signals.
  • TX The TVI interface chip is indicated in the text.
  • Pull-up is to clamp the indeterminate signal through a resistor at a high level, and the resistor acts as a current limiter.
  • an embodiment of a switching circuit for a video signal is provided.
  • the switching circuit of the video signal includes: an adjustment circuit 10, a detection circuit 20, and a controller 30, wherein The circuit 10 is connected to the first cable for adjusting the first cable to be in a pulled-up state or in a released state, wherein the first cable is a cable for transmitting a composite video signal; the detecting circuit 20 is connected to the first cable for detecting a first voltage value on the first cable when the first cable is in the pulled-up state, or a second voltage value on the first cable in the case where the first cable is in the released state; the controller 30 is configured to determine from the detecting circuit 20 a change of the first voltage value or the second voltage value, wherein, in a case where it is determined that the second voltage value becomes large, the controller controls the second cable to transmit the video signal, or determines that the first voltage value becomes small Next, the controller controls the first cable to transmit the video signal, and the second cable is the cable that transmits
  • the switching circuit of the video signal provided by the embodiment of the present invention adjusts the first cable to be in a pull-up state or a release state by adjusting the circuit, wherein the adjustment circuit is connected to the first cable, and the first cable is in a pull-up state.
  • the first voltage value on the first cable is detected to determine whether the first voltage value is small. If the first voltage value is unchanged, the second cable is continuously controlled to transmit the video signal, and the adjusting circuit adjusts the first cable to be in a released state. .
  • the second voltage value on the first cable is detected, and when it is detected that the second voltage value becomes large, the controller controls the second cable to transmit the video signal.
  • the adjusting circuit adjusts the first cable to be in a pull-up state. If the second voltage value does not change, the first cable is continuously controlled to transmit a video signal, wherein the detecting circuit is also connected to the first cable, so that it is not necessary to manually switch the gear position.
  • the purpose of the video signal switching is realized, thereby realizing the technical effect of adaptively switching the video signal, thereby solving the technical problem that the adaptive switching of the video signal cannot be realized due to the manual switching of the signal gear position in the prior art.
  • FIG. 4 is a schematic diagram of another optional switching circuit for a video signal according to an embodiment of the present invention.
  • the camera establishes a connection with a DVR through a first cable and a second cable.
  • the first cable may be The cable for transmitting the composite video signal CVBS
  • the second cable may be the cable for the video transmission interface output signal TVI.
  • Control the connection state between the first cable and the DVR DVR.
  • the connection status changes, the voltage value on the first cable also changes.
  • the sampled voltage value is analyzed in the “controller” shown in Figure 4.
  • the first cable outputs the composite video signal CVBS or the second cable output video transmission interface output signal TVI according to the change of the voltage value.
  • the controller defaults the second cable to output the video transmission interface output signal TVI.
  • FIG. 5 is a schematic diagram of another optional switching circuit of a video signal according to an embodiment of the present invention.
  • the switching circuit of the video signal further includes: a filter circuit 40 and a serial port configuration circuit 50, as shown in FIG.
  • the switching circuit of the video signal further includes: a Universal Asynchronous Receiver/Transmitter (UART); an interface chip for outputting a video transmission interface output signal TVI; and a DDT (Digital Video Recorder)
  • the filter circuit 40 is connected to the adjustment circuit 10 and the detection circuit 20 for filtering the second voltage value in the case of controlling the first cable to transmit the video signal, wherein the detection circuit 20 The filtered second voltage value is sampled;
  • the serial port configuration circuit 50 is connected to the controller 30 through the asynchronous transceiver UART, wherein the controller 30 controls the first cable to transmit a video signal or control through the serial port configuration circuit 50.
  • Two cables transmit video signals.
  • the implementation of the switching circuit of the video signal mainly includes five modules of the adjustment circuit 10, the detection circuit 20, the controller 30, the filter circuit 40, and the serial port configuration circuit 50.
  • the first cable is controlled to be pulled up by the adjusting circuit 10, that is, pulled up to 3.3V. If it is detected that the first voltage value on the first cable does not change, it can be determined that the second cable continues with the hard disk recorder. The DVR remains connected, and the second cable continues to transmit the video signal. If the first voltage value on the first cable is detected to decrease, it can be determined that the first cable is connected to the DVR DVR in FIG. 5, which is equivalent to the first cable.
  • the controller 30 transmits and receives asynchronously
  • the transmitter UART configures the serial port configuration circuit 50 to directly transmit the composite video signal CVBS from the first cable, while adjusting the first cable in the released state by the adjustment circuit 10. Then, the change of the voltage value on the first cable is continuously detected, and the detected voltage value is the second voltage value. If it is detected that the second voltage value on the first cable does not change, the first cable can be determined. Continue to maintain the connection with the DVR DVR, the first cable continues to transmit the video signal, if it is detected that the second voltage value on the first cable rises, it can be determined that the first cable is disconnected from the DVR DVR in FIG.
  • the controller 30 configures the serial port configuration circuit 50 to output the digital data signal BT.1120 to the interface chip shown in FIG. 5 through the asynchronous transceiver transmitter UART, and the interface chip transmits the video by the second cable.
  • the transmission interface outputs a signal TVI, and the adjustment circuit is used to adjust the first cable to be in a pull-up state.
  • the BT.1120 is a digital high-definition video data format protocol, and the digital data signal is represented in the text.
  • the controller 30 controls the serial port configuration circuit 50 to directly transmit the composite video signal CVBS by the first cable
  • the controller 30 detects that the sampled voltage value fluctuates greatly, and in order to avoid interference, the filter is added.
  • the circuit 40 filters the composite video signal CVBS via the filter circuit 40 and sends it to the controller 30 for detection.
  • the conditioning circuit 10 causes the first cable to be in a pull up state or in a released state.
  • FIG. 6 is a schematic diagram of another optional switching circuit of a video signal according to an embodiment of the present invention.
  • the adjusting circuit 10 includes: a first resistor R1, a second resistor R2, a transistor Q1, and a third resistor.
  • the first end of the first resistor R1 is connected to the high level
  • the first end of the second resistor R2 is connected to the output end of the first input signal
  • the second end of the second resistor R2 The terminal is connected to the second end of the first resistor R1, wherein the first input signal is a pin output signal of the controller
  • the base of the transistor Q1 is connected to the second end of the first resistor R1, and the collector of the transistor Q1 is connected Connected to the high level
  • the first end of the third resistor R3 is connected to the input end of the first cable, the second end of the third resistor R3 is connected to the emitter of the transistor Q1
  • the first end of the first capacitor C1 Connected to the second end of the first resistor R1, the second end of the first capacitor C1 is connected to the ground.
  • the filter circuit 40 includes: a fourth resistor R4 and a second capacitor C2, wherein the first end of the fourth resistor R4 is connected to the input end of the first cable; the first end of the second capacitor C2 is The second end of the four resistor R4 is connected, and the second end of the second capacitor C2 is connected to the ground.
  • the switching circuit further includes: an AD sampling port of the controller 30, the AD sampling port is connected to the second end of the fourth resistor R4; the first end of the fifth resistor R5 is connected to the input end of the first cable, and the fifth resistor R5 The second end is connected to the ground.
  • the "CVBS” signal shown in FIG. 6 is the signal output by the serial port configuration circuit 50, "CVBS_OUT” is the first cable interface output signal, “CVBS_DET” is the AD sampling port of the controller 30, and the IO1 signal is the first.
  • the input signal that is, the pin output signal of the controller 30.
  • the transistor Q1 in the control adjusting circuit 10 When the controller 30 controls the IO1 pin output signal to be low level, the transistor Q1 in the control adjusting circuit 10 is turned on, and when the controller 30 controls the IO1 pin output signal to be at a high level, the control adjusting circuit is controlled. The transistor Q1 in 10 is cut off.
  • the composite video signal CVBS is output on the first cable, since the composite video signal CVBS includes a signal of a high frequency component, the composite circuit is configured by the filter circuit 40 composed of the fourth resistor R4 and the second capacitor C2 shown in FIG.
  • the signal CVBS performs filtering processing to eliminate interference caused by the high frequency signal in the subsequent video switching process.
  • the composite video signal CVBS processed by the filter circuit 40 is sampled by the AD sampling port of the controller 30, and the sampled data is transmitted to the controller 30 for further determination.
  • the resistance of the first resistor R1 can be selected as 100K ⁇
  • the resistance of the second resistor R2 can be selected as 1K ⁇
  • the resistance of the fourth resistor R4 can be selected as 22K ⁇
  • the value of the first capacitor C1 can be selected as 10nF.
  • the value of the second capacitor can be chosen to be 1 uF.
  • FIG. 7 is a schematic diagram of an equivalent circuit for controlling a first cable to transmit a video signal without a connection to a load, in accordance with an embodiment of the present invention.
  • the controller 30 controls the first input signal IO1 to output a low level, so that the first cable is in a pull-up state, and the transistor Q1 is turned on.
  • the transistor Q1, the third resistor R3 and the fifth resistor R5 form a voltage dividing circuit, 3.3V. After Q1, the voltage drops to about 3.0V.
  • the voltage of the AD sampling port CVBS_DET of the controller 30 drops to about 1.6V.
  • the first cable is not connected to the DVR DVR, so the controller 30 outputs the video transmission interface output signal TVI through the control serial port configuration circuit 50, and there is no output of the composite video signal CVBS on the first cable, so the filter circuit 40 does not start.
  • FIG. 8 is a schematic diagram of an equivalent circuit for controlling a first cable to transmit a video signal in a case where a switching circuit of a video signal is connected to a load according to an embodiment of the present invention.
  • the controller 30 controls the first input signal IO1 pin to output a low level, so that the transistor Q1 is turned on.
  • the transistor Q1 and the third resistor R3, and the fifth resistor R5 form a voltage dividing circuit, when the first cable is connected to the hard disk recorder.
  • DVR that is, when the first cable interface output signal CVBS_OUT is connected to the load Rx, the resistance value of the load RX can be selected as 75 ⁇ .
  • the circuit is simplified as shown in FIG. 8.
  • the voltage value of the AD sampling port CVBS_DET of the controller 30 drops to about 1.0 V, that is, the first voltage value drops to about 1.0 V. Therefore, when the first voltage value is reduced from 1.6V to about 1.0V, the controller 30 determines that the first cable interface output signal CVBS_OUT is connected to the load, and the control serial port configuration circuit 50 outputs the composite video signal CVBS, and the controller 30 controls the first input.
  • the signal IO1 pin outputs a high level, and the transistor Q1 is in an off state.
  • FIG. 9 is a schematic diagram of an equivalent circuit for controlling a second cable to transmit a video signal in a case where a switching circuit of a video signal is connected to a load according to an embodiment of the present invention.
  • the controller 30 controls the serial port configuration circuit 50 to output a composite video signal, that is, the signal input at the "CVBS" end in FIG. 9 is simplified.
  • the fifth resistor R5 and the load Rx are connected in parallel to obtain a parallel equivalent resistance R, wherein the resistance of the parallel equivalent resistor R is 39 ⁇ , and the fourth resistor R4 and the second capacitor C2 constitutes a filter circuit 40.
  • the voltage of the AD sampling port CVBS_DET of the controller 30 after being filtered by the filter circuit 40 is a DC level, wherein the filter circuit 40 is a low-pass filter.
  • FIG. 10 is a schematic diagram of an equivalent circuit for transmitting a video signal of a second cable in a case where a switching circuit of a video signal is not connected to a load according to an embodiment of the present invention.
  • the circuit is simplified as shown in FIG. 10, and the signal value of the AD sampling port CVBS_DET of the controller 30 is increased from the original 0.615V to 0.68V to the original Doubled from 1.23V to 1.36V, that is, the second voltage value is increased from the original 0.615V to 0.68V to twice the original 1.23V to 1.36V.
  • the controller 30 determines that the second cable outputs the video transmission interface output signal TVI, the controller 30 outputs the TVI signal through the serial port configuration circuit 50, and the controller 30 controls the first input signal IO1 pin to output a low level, and the control transistor Q1 is at On state.
  • the embodiment of the invention further provides a method for switching a video signal, which can be used in the switching circuit of the video signal in the embodiment of the invention. It should be noted that although the switching method of the embodiment of the present invention shows a logical sequence in the flowchart, in some cases, the steps shown or described may be performed in an order different from that herein.
  • FIG. 11 is a flowchart of a method for switching an optional video signal according to an embodiment of the present invention. As shown in FIG. 11, the method includes the following steps S1102 to S1110:
  • Step S1102 adjusting the first cable to be in a pull-up state, wherein the first cable is a cable for transmitting a composite video signal.
  • Step S1104 detecting a first voltage value on the first cable when the first cable is in the pulled-up state, or detecting a second voltage value on the first cable when the first cable is in the released state.
  • Step S1106 determining a change in the first voltage value or the second voltage value.
  • step S1108 when it is determined that the first voltage value is small, the video signal is transmitted through the first cable.
  • Step S1110 in the case that it is determined that the second voltage value becomes large, the video signal is transmitted through the second cable, wherein the second cable is a cable that transmits a signal output signal of the video transmission interface, specifically, when it is determined that the voltage value becomes large In the case where the first cable is not connected to the load, the video signal is transmitted through the second cable.
  • the second cable is a cable that transmits a signal output signal of the video transmission interface, specifically, when it is determined that the voltage value becomes large
  • the video signal is transmitted through the second cable.
  • the switching method of the video signal adjusts the first cable to be in a pull-up state or a release state by adjusting the circuit, wherein the adjustment circuit is connected to the first cable, and the first cable is in a pull-up state.
  • the first voltage value on the first cable is detected to determine whether the first voltage value is small. If the first voltage value is unchanged, the second cable is continuously controlled to transmit the video signal, and the adjusting circuit adjusts the first cable to be in a released state. .
  • the controller controls the second cable to transmit the video signal.
  • the first cable is in a pull-up state. If the second voltage value is unchanged, the first cable is continuously controlled to transmit a video signal, wherein the detection circuit is also connected to the first cable, so that the manual switching of the gear position is not required to realize the video signal switching.
  • the purpose of the invention is to achieve the technical effect of adaptively switching the video signal, thereby solving the technical problem that the adaptive switching of the video signal cannot be realized due to the need to manually switch the signal gear position in the prior art.
  • the first cable is controlled to transmit the composite video signal CVBS, and since the signal of the first cable is a high frequency signal, when the composite video signal CVBS is output The detected sampling voltage value fluctuates greatly.
  • a filtering circuit is added to filter the second voltage value, and the composite video signal CVBS is filtered and then detected.
  • the first cable is in a pull-up state by controlling the first input signal to output a low level; the first cable is in a released state by controlling the first input signal to output a high level, wherein the first input signal is a controller Pin output signal.
  • the disclosed technical contents may be implemented in other manners.
  • the device embodiments described above are only schematic.
  • the division of the unit may be a logical function division.
  • there may be another division manner for example, multiple units or components may be combined or may be Integrate into another system, or some features can be ignored or not executed.
  • the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, unit or module, and may be electrical or otherwise.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Human Computer Interaction (AREA)
  • Two-Way Televisions, Distribution Of Moving Picture Or The Like (AREA)
  • Dc Digital Transmission (AREA)

Abstract

一种视频信号的切换电路和切换方法。其中，该切换电路包括：调节电路，与第一电缆相连接，用于调节第一电缆处于上拉状态或处于释放状态；检测电路，与第一电缆相连接，用于检测第一电缆处于上拉状态情况下第一电缆上的第一电压值，或检测第一电缆处于释放状态情况下第一电缆上的第二电压值；控制器，用于判断来自检测电路的第一电压值或第二电压值的变化，其中，在判断出第二电压值变大的情况下，控制器控制第二电缆传输视频信号，或在判断出第一电压值变小的情况下，控制器控制第一电缆传输视频信号。由此解决了由于现有技术中需要手动切换信号档位造成的不能实现自适应的切换视频信号的技术问题。

Description

视频信号的切换电路和切换方法 技术领域
本发明涉及视频监控技术领域，具体而言，涉及一种视频信号的切换电路和切换方法。
背景技术
现有技术中传输接口输出信号TVI(Transport Video Interface)和复合视频信号CVBS(Composite Video Broadcast Signal或Composite Video Blanking and Sync)切换的方式主要有两种，一种是摄像机内部的拨码开关切换方式，另外一种是摄像机出线的线缆搭接方式。
第一种拨码开关切换的方法，此方案的TVI和CVBS输出切换方式是通过拨码开关选择，拨码开关一般在摄像机内部的PCB板上，当需要切换输出的时候先把相应的BNC线缆连接到硬盘录像机DVR(Digital Video Recorder)上，然后打开机器壳，把拨码开关拨到相应位置，实现切换，方案的缺点是：打开机器壳操作比较麻烦，而且拨码开关的体积较大，占用较大的PCB空间，在结构上存在一定的干涉，不利于用户操作。图1是现有技术中的一种视频信号的切换方法的示意图，如图1所示，需要安装在摄像机中的拨码开关来手动实现档位的切换，图1中，第一电缆是传输复合视频信号CVBS的电缆，第二电缆是视频传输接口输出信号TVI的电缆。
第二种线缆搭接切换的方法，此方案的TVI和CVBS输出切换方式是通过搭接机器引出的两根控制线，默认输出一种信号，搭接时输出另一种信号。方案的缺点是：线缆引出且裸露容易带来静电等问题，而且线缆扭动会有机械疲损，也容易受外力作用接触松动，影响机器使用。图2是现有技术中的另一种视频信号的切换方法的示意图，如图2所示，在摄像机一侧引出了两根搭接线1和搭接线2，通过选择将搭接线连接在DVR上，再将TVI和CVBS信号线搭接在DVR上实现信号的切换，图2中，第一电缆是传输复合视频信号CVBS的电缆，第二电缆是视频传输接口输出信号TVI的电缆。
针对上述的问题，目前尚未提出有效的解决方案。
发明内容
本发明实施例提供了一种视频信号的切换电路和切换方法，以至少解决由于现有技术中需要手动切换信号档位造成的不能实现自适应的切换视频信号的技术问题。
根据本发明实施例的一个方面，提供了一种视频信号的切换电路，包括：调节电路，与第一电缆相连接，用于调节所述第一电缆处于上拉状态或处于释放状态，其中，所述第一电缆为传输复合视频信号的电缆；检测电路，与所述第一电缆相连接，用于检测所述第一电缆处于所述上拉状态情况下所述第一电缆上的第一电压值，或检测所述第一电缆处于所述释放状态情况下所述第一电缆上的第二电压值；控制器，用于判断来自所述检测电路的所述第一电压值或所述第二电压值的变化，其中，在判断出所述第二电压值变大的情况下，所述控制器控制第二电缆传输视频信号，或在判断出所述第一电压值变小的情况下，所述控制器控制第一电缆传输视频信号，所述第二电缆为传输视频传输接口输出信号的电缆。
进一步地，所述调节电路包括：第一电阻，所述第一电阻的第一端与高电平相连接；第二电阻，所述第二电阻的第一端与第一输入信号的输出端相连接，所述第二电阻的第二端与所述第一电阻的第二端相连接，其中，所述第一输入信号为所述控制器的管脚输出信号；三极管，所述三极管的基极与所述第一电阻的第二端相连接，所述三极管的集电极与高电平相连接；第三电阻，所述第三电阻的第一端与所述第一电缆的输入端相连接，所述第三电阻的第二端与所述三极管的发射极相连接；第一电容，所述第一电容的第一端与所述第一电阻的第二端相连接，所述第一电容的第二端与接地端相连接。
进一步地，所述切换电路还包括：滤波电路，与所述调节电路和所述检测电路均相连接，用于在控制第一电缆传输所述视频信号的情况下，对所述第二电压值进行滤波处理，其中，所述检测电路对经过滤波后的所述第二电压值进行采样。
进一步地，所述滤波电路包括：第四电阻，所述第四电阻的第一端与所述第一电缆的输入端相连接；第二电容，所述第二电容的第一端与所述第四电阻的第二端相连接，所述第二电容的第二端与接地端相连接。
进一步地，所述切换电路还包括：所述控制器的AD采样端口，所述AD采样端口与所述第四电阻的第二端相连接。
进一步地，所述切换电路还包括：串口配置电路，通过异步收发传输器与所述控制器相连接，其中，所述控制器通过所述串口配置电路控制所述第一电缆传输所述视频信号或所述第二电缆传输所述视频信号。
进一步地，所述切换电路还包括：第五电阻，所述第五电阻的第一端与所述第一 电缆的输入端相连接，所述第五电阻的第二端与接地端相连接。
根据本发明实施例的另一方面，还提供了一种视频信号的切换方法，包括：调节第一电缆处于上拉状态或处于释放状态，其中，所述第一电缆为传输复合视频信号的电缆；检测所述第一电缆处于所述上拉状态情况下所述第一电缆上的第一电压值，或检测所述第一电缆处于所述释放状态情况下所述第一电缆上的第二电压值；判断所述第一电压值或所述第二电压值的变化；在判断出所述第一电压值变小的情况下，通过所述第一电缆传输视频信号；在判断出所述第二电压值变大的情况下，通过第二电缆传输视频信号，其中，所述第二电缆为传输视频传输接口输出信号的电缆。
进一步地，在判断出所述第一电压值变小的情况下，通过所述第一电缆传输所述视频信号之后，所述方法还包括：对所述第二电压值进行滤波。
进一步地，在判断出所述第一电压值变小的情况下，通过所述第一电缆传输所述视频信号之后，所述方法还包括：调节所述第一电缆处于所述释放状态。
进一步地，通过控制第一输入信号的输出低电平，使所述第一电缆处于上拉状态，其中，所述第一输入信号为控制器的管脚输出信号；通过控制所述第一输入信号的输出高电平，使所述第一电缆处于释放状态。
在本发明实施例中，采用调节电路，与第一电缆相连接，用于调节第一电缆处于上拉状态或处于释放状态，其中，第一电缆为传输复合视频信号的电缆；检测电路，与第一电缆相连接，用于检测第一电缆处于上拉状态情况下第一电缆上的第一电压值，或检测第一电缆处于释放状态情况下第一电缆上的第二电压值；控制器，用于判断来自检测电路的第一电压值或第二电压值的变化，其中，在判断出第二电压值变大的情况下，控制器控制第二电缆传输视频信号，或在判断出第一电压值变小的情况下，控制器控制第一电缆传输视频信号的方式，所述第二电缆为传输视频传输接口输出信号的电缆。通过调节电路来调节第一电缆处于上拉状态或处于释放状态，其中，调节电路与第一电缆相连接，在第一电缆处于上拉状态的情况下，检测到第一电缆上的第一电压值判断第一电压值是否变小，如果第一电压值不变，继续控制第二电缆传输视频信号，同时调节电路调节第一电缆处于释放状态。在第一电缆处于释放状态的情况下，检测到第一电缆上的第二电压值，当检测到第二电压值变大的情况下，控制器控制第二电缆传输视频信号。同时调节电路调节第一电缆处于上拉状态，如果第二电压值不变，继续控制第一电缆传输视频信号，其中，检测电路也与第一电缆相连接，达到了不需要手动切换档位来实现视频信号切换的目的，从而实现了自适应切换视频信号的技术效果，进而解决了由于现有技术中需要手动切换信号档位造成的不能实现自适应的切换视频信号的技术问题。
附图说明
此处所说明的附图用来提供对本发明的进一步理解，构成本申请的一部分，本发明的示意性实施例及其说明用于解释本发明，并不构成对本发明的不当限定。在附图中：
图1是根据现有技术中的一种视频信号的切换方法的示意图；
图2是根据现有技术中的另一种视频信号的切换方法的示意图；
图3是根据本发明实施例的一种可选的视频信号的切换电路的示意图；
图4是根据本发明实施例的另一种可选的视频信号的切换电路的示意图；
图5是根据本发明实施例的另一种可选的视频信号的切换电路的示意图；
图6是根据本发明实施例的另一种可选的视频信号的切换电路的示意图；
图7是根据本发明实施例的视频信号的切换电路在未连接至负载的情况下控制第一电缆传输视频信号的等效电路的示意图；
图8是根据本发明实施例的视频信号的切换电路在连接至负载的情况下控制第一电缆传输视频信号的等效电路的示意图；
图9是根据本发明实施例的视频信号的切换电路在连接至负载的情况下控制第二电缆传输视频信号的等效电路的示意图；
图10是根据本发明实施例的视频信号的切换电路在未连接至负载的情况下第二电缆传输视频信号的等效电路的示意图；以及
图11是根据本发明实施例的一种可选的视频信号的切换方法的流程图。
具体实施方式
为了使本技术领域的人员更好地理解本发明方案，下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清楚、完整地描述，显然，所描述的实施例仅仅是本发明一部分的实施例，而不是全部的实施例。基于本发明中的实施例，本领域普通技术人员在没有做出创造性劳动前提下所获得的所有其他实施例，都应当属于本发明保护的范围。
需要说明的是，本发明的说明书和权利要求书及上述附图中的术语“第一”、“第二”等是用于区别类似的对象，而不必用于描述特定的顺序或先后次序。应该理解这样使用的数据在适当情况下可以互换，以便这里描述的本发明的实施例能够以除了在这里 图示或描述的那些以外的顺序实施。此外，术语“包括”和“具有”以及他们的任何变形，意图在于覆盖不排他的包含，例如，包含了一系列步骤或单元的过程、方法、系统、产品或设备不必限于清楚地列出的那些步骤或单元，而是可包括没有清楚地列出的或对于这些过程、方法、产品或设备固有的其它步骤或单元。
首先，对本实施例涉及的技术术语作如下解释：
HD-TVI:(Hight Definition-Transport Video Interface)是一种基于同轴电缆的高清视频传输规范，文中指高清视频传输接口输出信号。
CVBS:(Composite Video Broadcast Signal或Composite Video Blanking and Sync)即复合视频信号，包含了亮度信号、色度信号与同步信号(包括场同步、行同步信号及行场消隐信号)。
自适应：指处理和分析的过程中，根据处理数据的特征自动调整处理方法，使其与外部需求相适应。
BNC线缆：(Bayonet Nut Connector)带有连接器的同轴电缆。
UART：即通用异步收发传输器(Universal Asynchronous Receiver/Transmitter)，是一种异步收发传输器。
BT.1120：是一种数字高清视频数据格式协议，在文中表示数字数据信号。
TX：在文中表示TVI接口芯片。
上拉：上拉就是将不确定的信号通过一个电阻钳位在高电平，电阻同时起限流作用。
根据本发明实施例，提供了一种视频信号的切换电路的实施例。
图3是根据本发明实施例的一种可选的视频信号的切换电路的示意图，如图3所示，视频信号的切换电路包括：调节电路10、检测电路20和控制器30，其中，调节电路10与第一电缆相连接，用于调节第一电缆处于上拉状态或处于释放状态，其中，第一电缆为传输复合视频信号的电缆；检测电路20与第一电缆相连接，用于检测第一电缆处于上拉状态情况下第一电缆上的第一电压值，或检测第一电缆处于释放状态情况下第一电缆上的第二电压值；控制器30，用于判断来自检测电路20的第一电压值或第二电压值的变化，其中，在判断出第二电压值变大的情况下，控制器控制第二电缆传输视频信号，或在判断出第一电压值变小的情况下，控制器控制第一电缆传输视频信号，第二电缆为传输视频传输接口输出信号的电缆。
本发明实施例所提供的视频信号的切换电路，通过调节电路来调节第一电缆处于上拉状态或处于释放状态，其中，调节电路与第一电缆相连接，在第一电缆处于上拉状态的情况下，检测到第一电缆上的第一电压值判断第一电压值是否变小，如果第一电压值不变，继续控制第二电缆传输视频信号，同时调节电路调节第一电缆处于释放状态。在第一电缆处于释放状态的情况下，检测到第一电缆上的第二电压值，当检测到第二电压值变大的情况下，控制器控制第二电缆传输视频信号。同时调节电路调节第一电缆处于上拉状态，如果第二电压值不变，继续控制第一电缆传输视频信号，其中，检测电路也与第一电缆相连接，达到了不需要手动切换档位来实现视频信号切换的目的，从而实现了自适应切换视频信号的技术效果，进而解决了由于现有技术中需要手动切换信号档位造成的不能实现自适应的切换视频信号的技术问题。
图4是根据本发明实施例的另一种可选的视频信号的切换电路的示意图，如图4所示，摄像机通过第一电缆和第二电缆与硬盘录像机DVR建立连接，第一电缆可以是传输复合视频信号CVBS的电缆，第二电缆可以是视频传输接口输出信号TVI的电缆。控制第一电缆与硬盘录像机DVR的连接状态，当连接状态发生变化，第一电缆上的电压值也会发生改变，在图4中所示的“控制器”中对采样得到的电压值进行分析，根据电压值的变化情况控制第一电缆输出复合视频信号CVBS或控制第二电缆输出视频传输接口输出信号TVI。其中，在第一电缆未连接至硬盘录像机DVR的情况下，控制器默认第二电缆输出视频传输接口输出信号TVI。
图5是根据本发明实施例的另一种可选的视频信号的切换电路的示意图，如图5所示，视频信号的切换电路还包括：滤波电路40和串口配置电路50，如图5所示，除了上述装置以外，视频信号的切换电路的还包括：异步收发传输器(Universal Asynchronous Receiver/Transmitter，简称UART)；接口芯片，用于输出视频传输接口输出信号TVI；硬盘录像机(Digital Video Recorder，简称DVR)，其中，滤波电路40与调节电路10和检测电路20均相连接，用于在控制第一电缆传输视频信号的情况下，对第二电压值进行滤波处理，其中，检测电路20对经过滤波后的第二电压值进行采样；串口配置电路50，通过异步收发传输器UART与控制器30相连接，其中，控制器30通过串口配置电路50控制第一电缆传输视频信号或控制第二电缆传输视频信号。
具体地，视频信号的切换电路的实现主要包括调节电路10、检测电路20、控制器30、滤波电路40和串口配置电路50这五个模块。首先通过调节电路10控制第一电缆处于上拉状态，即，上拉到3.3V，如果检测出第一电缆上的第一电压值没有发生变化，此时可以判断出第二电缆继续与硬盘录像机DVR保持连接，第二电缆继续传输视频信号，如果检测出第一电缆上的第一电压值下降，此时可以判断出第一电缆与图5中的硬盘录像机DVR连接，相当于第一电缆已连接至负载，控制器30通过配异步收发 传输器UART配置串口配置电路50直接由第一电缆传输复合视频信号CVBS，同时利用调节电路10调节第一电缆处于释放状态。然后继续检测第一电缆上电压值的变化情况，此时检测出的电压值为第二电压值，如果检测出第一电缆上的第二电压值没有发生变化，此时可以判断出第一电缆继续与硬盘录像机DVR保持连接，第一电缆继续传输视频信号，如果检测出第一电缆上的第二电压值上升，此时可以判断出第一电缆与图5中的硬盘录像机DVR断开连接，此时第一电缆未连接至负载，控制器30通过配异步收发传输器UART配置串口配置电路50输出数字数据信号BT.1120给如图5所示的接口芯片，接口芯片由第二电缆传输视频传输接口输出信号TVI，同时利用调节电路调节第一电缆处于上拉状态，其中，BT.1120是一种数字高清视频数据格式协议，在文中表示数字数据信号。
当控制器30控制串口配置电路50直接由第一电缆传输复合视频信号CVBS，由于第一电缆上的信号是高频信号，控制器30检测采样电压值波动较大，为了避免干扰，所以加入滤波电路40，把复合视频信号CVBS经滤波电路40滤波之后再送到控制器30中进行检测。调节电路10使第一电缆处于上拉状态或处于释放状态。
图6是根据本发明实施例的另一种可选的视频信号的切换电路的示意图，如图6所示，调节电路10包括：第一电阻R1、第二电阻R2、三极管Q1、第三电阻R3和第一电容C1，其中，第一电阻R1的第一端与高电平相连接；第二电阻R2的第一端与第一输入信号的输出端相连接，第二电阻R2的第二端与第一电阻R1的第二端相连接，其中，第一输入信号为控制器的管脚输出信号；三极管Q1的基极与第一电阻R1的第二端相连接，三极管Q1的集电极与高电平相连接；第三电阻R3的第一端与第一电缆的输入端相连接，第三电阻R3的第二端与三极管Q1的发射极相连接；第一电容C1的第一端与第一电阻R1的第二端相连接，第一电容C1的第二端与接地端相连接。
如图6所示，滤波电路40包括：第四电阻R4和第二电容C2，其中，第四电阻R4第一端与第一电缆的输入端相连接；第二电容C2的第一端与第四电阻R4的第二端相连接，第二电容C2的第二端与接地端相连接。
切换电路还包括：控制器30的AD采样端口，AD采样端口与第四电阻R4的第二端相连接；第五电阻R5的第一端与第一电缆的输入端相连接，第五电阻R5的第二端与接地端相连接。
具体地，图6中所示的“CVBS”信号为串口配置电路50输出的信号，“CVBS_OUT”为第一电缆接口输出信号，“CVBS_DET”为控制器30的AD采样端口，IO1信号为第一输入信号，即控制器30的管脚输出信号。
当控制器30控制IO1管脚输出信号为低电平的情况下，控制调节电路10中的三极管Q1导通，当控制器30控制IO1管脚输出信号为高电平的情况下，控制调节电路10中的三极管Q1截止。当第一电缆上有复合视频信号CVBS输出时，由于复合视频信号CVBS包含高频成分的信号，所以利用图6中所示的第四电阻R4和第二电容C2构成的滤波电路40对复合视频信号CVBS进行滤波处理，排除高频信号对后续视频切换过程中带来的干扰。利用控制器30的AD采样端口将经过滤波电路40处理之后的复合视频信号CVBS进行采样，将采样数据传送至控制器30进行下一步判断。图6中第一电阻R1的阻值可以选取为100KΩ，第二电阻R2的阻值可以选取为1KΩ，第四电阻R4的阻值可以选取为22KΩ，第一电容C1的值可以选取为10nF，第二电容的值可以选取为1uF。
图7是根据本发明实施例的视频信号的切换电路在未连接至负载的情况下控制第一电缆传输视频信号的等效电路的示意图。当第一电缆还未接至硬盘录像机DVR，即未连接至负载的情况下，第一电缆上无复合视频信号CVBS输出。控制器30控制第一输入信号IO1输出低电平，使第一电缆处于上拉状态，使三极管Q1导通，此时三极管Q1、第三电阻R3和第五电阻R5构成分压电路，3.3V经过Q1后电压下降到约为3.0V，经过R3和R5分压，控制器30的AD采样端口CVBS_DET电压降至约为1.6V。此时第一电缆还未连接至硬盘录像机DVR，所以控制器30通过控制串口配置电路50输出视频传输接口输出信号TVI，第一电缆上没有复合视频信号CVBS的输出，所以滤波电路40不启动。
图8是根据本发明实施例的视频信号的切换电路在连接至负载的情况下控制第一电缆传输视频信号的等效电路的示意图。控制器30控制第一输入信号IO1引脚输出低电平，使三极管Q1导通，此时三极管Q1和第三电阻R3，第五电阻R5电阻形成分压电路，当第一电缆连接至硬盘录像机DVR，即当第一电缆接口输出信号CVBS_OUT接上负载Rx时，其中，负载RX的电阻值可以选取为75Ω。此时电路简化为如图8所示，此时控制器30的AD采样端口CVBS_DET电压值降至约为1.0V，即第一电压值降至约为1.0V。因此当第一电压值由1.6V降至约为1.0V，控制器30判断第一电缆接口输出信号CVBS_OUT接上负载，控制串口配置电路50输出复合视频信号CVBS，同时控制器30控制第一输入信号IO1引脚输出高电平，三极管Q1处于截止状态。
图9是根据本发明实施例的视频信号的切换电路在连接至负载的情况下控制第二电缆传输视频信号的等效电路的示意图。如图9所示，当第一电缆接口输出信号CVBS_OUT接上负载Rx，控制器30控制串口配置电路50输出复合视频信号，即图9中的“CVBS”端有信号输入，此时电路简化如图9所示，第五电阻R5和负载Rx并联得到并联等效电阻R，其中并联等效电阻R的阻值为39Ω，第四电阻R4和第二电容 C2构成滤波电路40，经过滤波电路40滤波之后的控制器30的AD采样端口CVBS_DET电压值为直流电平，其中，滤波电路40为低通滤波器。
图10是根据本发明实施例的视频信号的切换电路在未连接至负载的情况下第二电缆传输视频信号的等效电路的示意图。当第一电缆接口输出信号CVBS_OUT与负载Rx断开时，此时电路简化为如图10所示，控制器30的AD采样端口CVBS_DET信号电压值由原来的0.615V～0.68V增大至原来的两倍1.23V～1.36V，即第二电压值由原来的0.615V～0.68V增大至原来的两倍1.23V～1.36V。此时控制器30判断第二电缆输出视频传输接口输出信号TVI，控制器30通过串口配置电路50输出TVI信号，同时控制器30控制第一输入信号IO1引脚输出低电平，控制三极管Q1处于导通状态。
本发明实施例还提供了一种视频信号的切换方法，该方法可以用于本发明实施例的视频信号的切换电路。需要说明的是，本发明实施例的切换方法虽然在流程图中示出了逻辑顺序，但是在某些情况下，可以以不同于此处的顺序执行所示出或描述的步骤。
图11是根据本发明实施例的一种可选的视频信号的切换方法的流程图，如11图所示，该方法包括如下步骤S1102至步骤S1110：
步骤S1102，调节第一电缆处于上拉状态，其中，第一电缆为传输复合视频信号的电缆。
步骤S1104，检测第一电缆处于上拉状态情况下第一电缆上的第一电压值，或检测第一电缆处于释放状态情况下第一电缆上的第二电压值。
步骤S1106，判断第一电压值或所述第二电压值的变化。
步骤S1108，在判断出第一电压值变小的情况下，通过第一电缆传输视频信号。
步骤S1110，在判断出第二电压值变大的情况下，通过第二电缆传输视频信号，其中，第二电缆为传输视频传输接口输出信号的电缆，具体地，当判断出电压值变大的情况下，说明第一电缆未连接至负载，所以通过第二电缆传输视频信号。
本发明实施例所提供的视频信号的切换方法，通过调节电路来调节第一电缆处于上拉状态或处于释放状态，其中，调节电路与第一电缆相连接，在第一电缆处于上拉状态的情况下，检测到第一电缆上的第一电压值判断第一电压值是否变小，如果第一电压值不变，继续控制第二电缆传输视频信号，同时调节电路调节第一电缆处于释放状态。在第一电缆处于释放状态的情况下，检测到第一电缆上的第二电压值，当检测到第二电压值变大的情况下，控制器控制第二电缆传输视频信号。同时调节电路调节 第一电缆处于上拉状态，如果第二电压值不变，继续控制第一电缆传输视频信号，其中，检测电路也与第一电缆相连接，达到了不需要手动切换档位来实现视频信号切换的目的，从而实现了自适应切换视频信号的技术效果，进而解决了由于现有技术中需要手动切换信号档位造成的不能实现自适应的切换视频信号的技术问题。
进一步地，当判断出第一电缆上的第一电压值变小的情况下，控制第一电缆传输复合视频信号CVBS，由于第一电缆的信号是高频信号，当有复合视频信号CVBS输出时，检测到的采样电压值波动较大，为了避免干扰，所以加入滤波电路，对第二电压值进行滤波，把复合视频信号CVBS经滤波之后再进行检测。
进一步地，在通过第一电缆传输复合视频信号CVBS之后，需要通过控制第一输入信号的输出调节第一电缆处于释放状态。主要通过控制第一输入信号输出低电平，使第一电缆处于上拉状态；通过控制第一输入信号输出高电平，使第一电缆处于释放状态，其中，第一输入信号为控制器的管脚输出信号。
上述本发明实施例序号仅仅为了描述，不代表实施例的优劣。
在本发明的上述实施例中，对各个实施例的描述都各有侧重，某个实施例中没有详述的部分，可以参见其他实施例的相关描述。
在本申请所提供的几个实施例中，应该理解到，所揭露的技术内容，可通过其它的方式实现。其中，以上所描述的装置实施例仅仅是示意性的，例如所述单元的划分，可以为一种逻辑功能划分，实际实现时可以有另外的划分方式，例如多个单元或组件可以结合或者可以集成到另一个系统，或一些特征可以忽略，或不执行。另一点，所显示或讨论的相互之间的耦合或直接耦合或通信连接可以是通过一些接口，单元或模块的间接耦合或通信连接，可以是电性或其它的形式。
以上所述仅是本发明的优选实施方式，应当指出，对于本技术领域的普通技术人员来说，在不脱离本发明原理的前提下，还可以做出若干改进和润饰，这些改进和润饰也应视为本发明的保护范围。

Claims (11)

  1. 一种视频信号的切换电路，包括：
    调节电路，与第一电缆相连接，用于调节所述第一电缆处于上拉状态或处于释放状态，其中，所述第一电缆为传输复合视频信号的电缆；
    检测电路，与所述第一电缆相连接，用于检测所述第一电缆处于所述上拉状态情况下所述第一电缆上的第一电压值，或检测所述第一电缆处于所述释放状态情况下所述第一电缆上的第二电压值；以及
    控制器，用于判断来自所述检测电路的所述第一电压值或所述第二电压值的变化，其中，在判断出所述第二电压值变大的情况下，所述控制器控制第二电缆传输视频信号，或在判断出所述第一电压值变小的情况下，所述控制器控制第一电缆传输视频信号，所述第二电缆为传输视频传输接口输出信号的电缆。
  2. 根据权利要求1所述的切换电路，其中，所述调节电路包括：
    第一电阻，所述第一电阻的第一端与高电平相连接；
    第二电阻，所述第二电阻的第一端与第一输入信号的输出端相连接，所述第二电阻的第二端与所述第一电阻的第二端相连接，其中，所述第一输入信号为所述控制器的管脚输出信号；
    三极管，所述三极管的基极与所述第一电阻的第二端相连接，所述三极管的集电极与高电平相连接；
    第三电阻，所述第三电阻的第一端与所述第一电缆的输入端相连接，所述第三电阻的第二端与所述三极管的发射极相连接；以及
    第一电容，所述第一电容的第一端与所述第一电阻的第二端相连接，所述第一电容的第二端与接地端相连接。
  3. 根据权利要求1所述的切换电路，其中，所述切换电路还包括：
    滤波电路，与所述调节电路和所述检测电路均相连接，用于在控制第一电缆传输所述视频信号的情况下，对所述第二电压值进行滤波处理，其中，所述检测电路对经过滤波后的所述第二电压值进行采样。
  4. 根据权利要求3所述的切换电路，其中，所述滤波电路包括：
    第四电阻，所述第四电阻的第一端与所述第一电缆的输入端相连接；以及
    第二电容，所述第二电容的第一端与所述第四电阻的第二端相连接，所述第二电容的第二端与接地端相连接。
  5. 根据权利要求4所述的切换电路，其中，所述切换电路还包括：所述控制器的AD采样端口，所述AD采样端口与所述第四电阻的第二端相连接。
  6. 根据权利要求1所述的切换电路，其中，所述切换电路还包括：
    串口配置电路，通过异步收发传输器与所述控制器相连接，其中，所述控制器通过所述串口配置电路控制所述第一电缆传输所述视频信号或所述第二电缆传输所述视频信号。
  7. 根据权利要求1所述的切换电路，其中，所述切换电路还包括：
    第五电阻，所述第五电阻的第一端与所述第一电缆的输入端相连接，所述第五电阻的第二端与接地端相连接。
  8. 一种视频信号的切换方法，包括：
    调节第一电缆处于上拉状态或处于释放状态，其中，所述第一电缆为传输复合视频信号的电缆；
    检测所述第一电缆处于所述上拉状态情况下所述第一电缆上的第一电压值，或检测所述第一电缆处于所述释放状态情况下所述第一电缆上的第二电压值；
    判断所述第一电压值或所述第二电压值的变化；
    在判断出所述第一电压值变小的情况下，通过所述第一电缆传输视频信号；以及
    在判断出所述第二电压值变大的情况下，通过第二电缆传输视频信号，其中，所述第二电缆为传输视频传输接口输出信号的电缆。
  9. 根据权利要求8所述的方法，其中，在判断出所述第一电压值变小的情况下，通过所述第一电缆传输所述视频信号之后，所述方法还包括：
    对所述第二电压值进行滤波。
  10. 根据权利要求8或9所述的方法，其中，在判断出所述第一电压值变小的情况下，通过所述第一电缆传输所述视频信号之后，所述方法还包括：
    调节所述第一电缆处于所述释放状态。
  11. 根据权利要求10所述的方法，其中：
    通过控制第一输入信号的输出低电平，使所述第一电缆处于上拉状态，其中，所述第一输入信号为控制器的管脚输出信号；以及
    通过控制所述第一输入信号的输出高电平，使所述第一电缆处于释放状态。
PCT/CN2015/097194 2015-06-29 2015-12-11 视频信号的切换电路和切换方法 WO2017000507A1 (zh)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US15/740,416 US10194113B2 (en) 2015-06-29 2015-12-11 Switching circuit and switching method for video signal
EP15897032.7A EP3316569B1 (en) 2015-06-29 2015-12-11 Switching circuit and switching method for video signal

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201510378151.5A CN106331531B (zh) 2015-06-29 2015-06-29 视频信号的切换电路和切换方法
CN201510378151.5 2015-06-29

Publications (1)

Publication Number Publication Date
WO2017000507A1 true WO2017000507A1 (zh) 2017-01-05

Family

ID=57607620

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2015/097194 WO2017000507A1 (zh) 2015-06-29 2015-12-11 视频信号的切换电路和切换方法

Country Status (4)

Country Link
US (1) US10194113B2 (zh)
EP (1) EP3316569B1 (zh)
CN (1) CN106331531B (zh)
WO (1) WO2017000507A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11553125B2 (en) 2018-09-13 2023-01-10 Sony Corporation Camera system and cables

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110536047B (zh) * 2018-05-25 2020-11-13 杭州海康威视数字技术股份有限公司 一种视频信号输出电路及摄像机

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101277403A (zh) * 2008-03-31 2008-10-01 深圳创维数字技术股份有限公司 一种数字电视接收机视频信号切换电路及方法
US20110157372A1 (en) * 2009-12-31 2011-06-30 Sunplus Technology Co., Ltd. Multimedia apparatus having function of detecting video signal connection
CN104679464A (zh) * 2013-11-30 2015-06-03 鸿富锦精密工业(武汉)有限公司 显示器信号切换系统和方法

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4199771B2 (ja) * 2003-05-28 2008-12-17 パナソニック株式会社 デジタルインターフェイス受信装置
JP4358854B2 (ja) * 2004-02-05 2009-11-04 パナソニック株式会社 テレビジョン受像機および電子デバイス装置
JP5515919B2 (ja) * 2010-02-12 2014-06-11 ソニー株式会社 電子機器および接続外部機器のデジタルインタフェース判別方法
CN102387331A (zh) * 2010-08-31 2012-03-21 宏碁股份有限公司 播放装置及方法
CN102318340B (zh) * 2011-06-17 2013-06-26 华为终端有限公司 一种确定需要输出的视频信号类型的方法及装置

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101277403A (zh) * 2008-03-31 2008-10-01 深圳创维数字技术股份有限公司 一种数字电视接收机视频信号切换电路及方法
US20110157372A1 (en) * 2009-12-31 2011-06-30 Sunplus Technology Co., Ltd. Multimedia apparatus having function of detecting video signal connection
CN104679464A (zh) * 2013-11-30 2015-06-03 鸿富锦精密工业(武汉)有限公司 显示器信号切换系统和方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3316569A4 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11553125B2 (en) 2018-09-13 2023-01-10 Sony Corporation Camera system and cables

Also Published As

Publication number Publication date
EP3316569A4 (en) 2019-01-16
US10194113B2 (en) 2019-01-29
EP3316569A1 (en) 2018-05-02
CN106331531A (zh) 2017-01-11
CN106331531B (zh) 2019-04-09
EP3316569B1 (en) 2020-01-15
US20180191985A1 (en) 2018-07-05

Similar Documents

Publication Publication Date Title
US20090153263A1 (en) Modulized wave filter
WO2016127537A1 (zh) 一种后端、前端的处理电路、及同轴供电电路
GB2454286A (en) Video transmitter and receiver systems with synchronised insertion and processing of control signals
KR101620102B1 (ko) 비디오 오버 이더넷
WO2017000507A1 (zh) 视频信号的切换电路和切换方法
CN106231230B (zh) 一种dp信号远距离传输装置
CN101175194B (zh) 自动校准复合视频信号电缆传输设备
JP3160156B2 (ja) 電灯線通信用ケーブル接続器
US20170104604A1 (en) Reverse power supply method, device and storage medium
WO2009035892A1 (en) Hdmi-quality content transmission along a single medium
US9432622B1 (en) High-speed video interfaces, video endpoints, and related methods
US9912708B2 (en) Systems and methods for duplex communication
CN110209371B (zh) 一种音频兼容电路及视音频设备
CN208424526U (zh) 一种整形电路及视频数据采集设备
EP2660990B1 (en) Asymmetric full duplex communication with high tolerance for coax characteristic impedance
US8482666B1 (en) Monitor device adapter
CN109962722B (zh) 一种发送装置及信号传输方法
JP4876754B2 (ja) ドアホン親機
CN111082830B (zh) 一种数字音频接口的数据环回检测电路和数字音频设备
US9231659B2 (en) Power line communication device with noise detecting and filtering functions
US8817006B2 (en) Adapter
CN210156694U (zh) 一种hdmi信号的传输线、接收头和传输系统
US20160337585A1 (en) Video signal extender
CN203219454U (zh) 一种通讯系统
JP4876753B2 (ja) ドアホン親機

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15897032

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2015897032

Country of ref document: EP