CN112689102B - Differential video transmission device and method - Google Patents
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Abstract
The invention relates to the technical field of video transmission, and provides a differential video transmission device and a differential video transmission method, wherein a feature extraction module is arranged to directly acquire an abnormal detection signal by feature acquisition of a differential video signal input by an AHD input port, and the abnormal detection is carried out at the beginning of signal input, so that the generation of the abnormal signal (fault generation) can be quickly reacted and the fault is repaired; the path selection module is arranged to match with the double paths of the fault restoration loop (the operational amplifier module, the signal selection module and the decoding module) and the normal output loop (the decoding module), when the signal is abnormal, the path selection module is switched to the fault restoration loop, and the signal amplification function of the operational amplifier module is utilized to amplify the single-ended signal (the positive signal or the negative signal) to a preset amplitude value, so that the working requirement of the decoding module is met, the normal transmission of the differential video signal is maintained, and the reliability of the differential video signal output system is further improved.
Description
Technical Field
The present invention relates to the field of video transmission technologies, and in particular, to a differential video transmission device and method.
Background
The AHD (Anolog HighDefinition, namely analog high-resolution) technology can realize reliable transmission of ultra-long-distance (500 m) high-definition video signals on the existing analog transmission line; the method adopts advanced Y/C signal separation and analog filtering technology, can effectively reduce the color noise in a high-frequency area, and has better image reducibility. Compared with the traditional analog high-definition product, the quality of the monitoring image of the AHD is improved and leapfrog, and the highest definition can be equal to the full high-definition level of network high-definition 1080P.
The digital high definition needs serialization and deserialization chips, the price is high, and the requirement on impedance shielding of a transmission line is high. The simulation high-definition AHD has low cost (common coaxial line) because of transmission harness, the image quality reaches high-definition level, and the 360 panorama of the simulation high-definition AHD and the utilization rate of the vehicle-mounted camera are higher and higher at present in the time of reducing the cost of the whole automobile.
However, when the current AHD signal is differentially transmitted, once a certain signal line in the transmission line fails, the picture cannot be normally displayed, and the display can be redisplayed after the line repair is required.
Accordingly, there is a need for further improvements in the art.
Disclosure of Invention
The invention provides a differential video transmission device and a differential video transmission method, which solve the technical problems of poor fault tolerance and slow fault repair of the existing AHD video transmission line.
In order to solve the technical problems, the invention provides a differential video transmission device which comprises a control module, a characteristic extraction module, a path selection module, a signal selection module, a fault isolation module, an operational amplifier module and a decoding module, wherein the characteristic extraction module, the path selection module, the signal selection module and the fault isolation module are connected with the control module; the fault isolation module is respectively connected with the path selection module and the decoding module;
the characteristic extraction module is connected with the AHD input port and is used for carrying out characteristic extraction on the differential video signal to obtain an abnormal detection signal;
the control module is used for generating a corresponding gating signal according to the abnormality detection signal, controlling the signal gating of the path selection module and the signal selection module, generating an isolation signal and sending the isolation signal to the fault isolation module;
the fault isolation module is used for responding to the isolation signal to isolate a fault line;
the path selection module is connected with an AHD input port and is used for responding to the gating signal and controlling the differential video signal to be output to the operational amplifier module or the decoding module;
the operational amplifier module is used for amplifying the positive signal or the negative signal of the differential video signal according to a preset fault restoration strategy;
the signal selection module is used for responding to the gating signal, gating the output end of the operational amplifier module and outputting a corresponding single-ended signal to the decoding module;
the decoding module is used for receiving the differential video signal or the single-ended signal and decoding.
The basic scheme is provided with the feature extraction module, and the feature acquisition is directly carried out on the differential video signals input by the AHD input port to obtain an abnormal detection signal, so that the abnormal detection is carried out at the beginning of the signal input, and the generation of the abnormal signal (fault generation) can be rapidly reacted and the fault repair can be carried out; the path selection module is matched with the dual paths of the fault restoration loop (the operational amplifier module, the signal selection module and the decoding module) and the normal output loop (the decoding module), the path selection module can be switched to the fault restoration loop when the signal is abnormal, and the signal amplification function of the operational amplifier module is utilized to amplify the single-ended signal (the positive signal or the negative signal) to a preset amplitude value, so that the working requirement of the decoding module is met, the normal transmission of the video signal is realized, and the reliability of the differential video signal output system is further improved.
In a further embodiment, the path selection module includes a first channel selection module and a second channel selection module; the first channel selection module and the second channel selection module are respectively connected with the positive electrode input end and the negative electrode input end of the AHD input port; the first channel selection module comprises a first output end and a second output end which are respectively connected with the operational amplifier module and the decoding module; the second channel selection module comprises a third output end and a fourth output end which are respectively connected with the operational amplifier module and the decoding module;
when the control module judges that the negative electrode signal is abnormal according to the abnormality detection signal, the signal output of the second channel selection module is closed, a first gating signal is generated, and the first channel selection module is controlled to gate a first output end;
when the control module judges that the positive signal is abnormal according to the abnormality detection signal, the signal output of the first channel selection module is closed, the first gating signal is generated, and the second channel selection module is controlled to gate a third output end;
when the control module judges that the differential video signal is normal according to the abnormality detection signal, the control module generates the first gating signal, controls the first channel selection module to gate the second output end and controls the second channel selection module to gate the fourth output end.
The scheme is that a first channel selection module and a second channel selection module which correspond to positive signal input and negative signal input respectively are arranged to establish a path selection module, the output of two paths of signals in a differential video signal is adjusted in a targeted mode, when one path of signals is abnormal (positive signal is abnormal or negative signal is abnormal), the signal output is closed, the other path of normal signals is output, and therefore when a certain branch line has faults, fault repair recovery signals are timely output.
In a further embodiment, the signal selection module comprises a first input terminal and a second input terminal independent of each other; when the positive electrode signal/the negative electrode signal is abnormal, the control module generates a second gating signal to control the signal selection module to gate the second input end/the first input end.
In a further embodiment, the operational amplifier module is provided with an in-phase amplifying circuit and an anti-phase amplifying circuit, and the in-phase amplifying circuit is connected with the first output end and the first input end; the inverting amplification circuit is connected with the third output end and the second input end;
the in-phase amplifying circuit is used for in-phase amplifying the positive electrode signal;
the inverting amplification circuit is used for inverting amplification of the negative electrode signal.
The scheme comprises an in-phase amplifying circuit and an inverting amplifying circuit operational amplifier module, can be compatible with positive signals and negative signals, and can amplify the positive signals/the negative signals in-phase or in-phase according to a preset amplitude value when a signal fault occurs, so that the positive signals meeting the decoding condition of the decoding module are obtained, and can be directly input into the decoding module for analysis.
In a further embodiment, the fault isolation module is a switch circuit, a control end of the switch circuit is connected with the control module, and a signal input end of the switch circuit is connected with the second output end and the fourth output end;
and when the control end receives the isolation signal, the signal input end and the grounding end are conducted, and the signal connection between the decoding module and the path selection module is disconnected.
The fault isolation module with the switching characteristic is designed, a signal input end is arranged on a connection point of the path selection module and the decoding module, and when a signal fault occurs, the signal input end and the grounding end are conducted in response to an isolated signal, so that the second output end of the first channel selection module and the fourth output end of the first channel selection module are grounded, signal interference of a fault line to the decoding module is isolated, and meanwhile reference ground is provided for single-ended signals output by the signal selection module.
The invention also provides a differential video transmission method, which adopts the differential video transmission device and comprises the following steps:
s1, acquiring a differential video signal and judging whether the differential video signal is abnormal or not;
and S2, when the differential video signal is abnormal, isolating a fault line, controlling a normal line to recover to output according to a preset fault repair strategy, and sending out prompt information of the abnormal differential video signal.
The basic scheme configures a corresponding fault repairing method for the fault repairing system, detects the state of the differential video signal in real time, isolates the fault line at the first time after detecting abnormal signal transmission, and controls the normal line to recover output according to the fault repairing strategy, so that the differential video signal can still be normally transmitted after the signal fault occurs, and the reliability of the differential video signal output system is further improved.
In a further embodiment, the step S1 includes:
s11, obtaining differential video signals in timing time and the number of theoretical synchronous signals;
s12, calculating the number of first synchronous signals of positive signals and the number of second synchronous signals of negative signals in the differential video signals in the timing time;
s13, respectively comparing the first synchronous signal quantity and the second synchronous signal quantity by taking the theoretical synchronous signal quantity as a standard, and if the comparison difference value is larger than a preset threshold value, representing signal abnormality.
According to the scheme, the theoretical synchronous signal quantity in the timing time is taken as a standard, the difference value calculation and the threshold value comparison are carried out by acquiring the first synchronous signal quantity and the second synchronous signal quantity which respectively correspond to the positive electrode signal and the negative electrode signal, and whether the line fault problem of signal abnormality exists can be clearly judged.
In a further embodiment, the step S2 includes:
s21a, when negative electrode signals in the differential video signals are abnormal, in-phase amplifying the input positive electrode signals to a preset amplitude value, and inputting the amplified single-ended signals to a first input end of a signal selection module;
s22a, disconnecting the output of the negative electrode signal and sending out prompt information of abnormality of the negative electrode signal.
In another embodiment, the step S2 includes:
s21b, when positive signals in the differential video signals are abnormal, carrying out reverse amplification on the input negative signals to a preset amplitude value, and inputting the amplified single-ended signals to a second input end of a signal selection module;
s22b, disconnecting the output of the positive electrode signal and sending out prompt information of abnormality of the positive electrode signal.
In yet another embodiment, the step S2 includes:
s21c, when the positive electrode signal and the negative electrode signal are judged to be abnormal at the same time, disconnecting the output of the positive electrode signal and the negative electrode signal in the differential video signal;
s22c, sending out prompt information that the positive electrode signal and the negative electrode signal are abnormal at the same time.
According to the scheme, corresponding fault coping strategies are designed aiming at different differential video signal abnormal conditions, when only one path of signal is abnormal (positive signal or negative signal is abnormal), the negative signal/positive signal which is still normally output by the other path is subjected to reverse phase amplification/in-phase amplification until the rest single-ended signal can meet the preset amplitude of a decoding module, so that the video signal is stably output; when the positive electrode signal and the negative electrode signal are abnormal at the same time, the output of the positive electrode signal and the negative electrode signal in the differential video signal is directly disconnected, so that unnecessary resource waste and secondary circuit damage are reduced; the signal abnormality prompt is utilized to remind workers of repairing faults in time.
In a further embodiment, the invention further comprises the steps of:
and S3, when the difference video signal is not judged to be abnormal, controlling the difference video signal to be directly output to a decoding module for decoding.
Drawings
Fig. 1 is a system frame diagram of a differential video transmission device according to embodiment 1 of the present invention;
FIG. 2 is a hardware circuit diagram of FIG. 1 provided by embodiment 1 of the present invention;
fig. 3 is a flowchart of a differential video transmission method according to embodiment 2 of the present invention.
Detailed Description
The following examples are given for the purpose of illustration only and are not to be construed as limiting the invention, including the drawings for reference and description only, and are not to be construed as limiting the scope of the invention as many variations thereof are possible without departing from the spirit and scope of the invention.
Example 1
Reference numerals in the drawings of the specification in this embodiment include: a control module 1, a feature extraction module 2, a path selection module 3, a first channel selection module 31 and a second channel selection module 32; the system comprises a signal selection module 4, a fault isolation module 5, an operational amplifier module 6 and a decoding module 7.
In the embodiment, as shown in fig. 1 and 2, the differential video transmission device provided by the embodiment of the invention comprises a control module 1, a feature extraction module 2, a path selection module 3, a signal selection module 4 and a fault isolation module 5 which are connected with the control module 1, and an operational amplifier module 6 and a decoding module 7 which are respectively connected with the path selection module 3 and the signal selection module 4; the fault isolation module 5 is respectively connected with the path selection module 3 and the decoding module 7;
the feature extraction module 2 is connected with an AHD input port and is used for carrying out feature extraction on the differential video signal to obtain an abnormal detection signal.
In this embodiment, the AHD input ports include ahd+ (positive input) and AHD- (negative input).
The feature extraction module 2 may select a video synchronization signal extraction module to extract a synchronization signal, or may select a shaping filtering module to convert a differential video signal into a level signal, so as to obtain an anomaly detection signal. A group of video synchronous signal extraction modules or shaping and filtering modules are respectively arranged for each path of signal input. In this embodiment, it is preferable that two sets of video synchronization signal extraction modules U1, U2 constitute the feature extraction module 2.
The control module 1 is used for generating corresponding gating signals according to the abnormality detection signals, controlling signal gating of the path selection module 3 and the signal selection module 4, generating isolation signals and sending the isolation signals to the fault isolation module 5;
in this embodiment, the control module 1 is preferably an MCU.
The fault isolation module 5 is used for isolating a fault line in response to the isolation signal;
the path selection module 3 is connected with an AHD input port and is used for responding to the gating signal and controlling the differential video signal to be output to the operational amplifier module 6 or the decoding module 7;
the operational amplifier module 6 is used for amplifying the positive electrode signal or the negative electrode signal of the differential video signal according to a preset fault restoration strategy;
the signal selection module 4 is used for responding to the gating signal, gating the output end of the operational amplifier module 6, and outputting a corresponding single-ended signal to the decoding module 7;
the decoding module 7 is configured to receive a differential video signal or a single-ended signal and perform decoding.
In a further embodiment, the path selection module 3 comprises a first channel selection module 31 and a second channel selection module 32; the first channel selection module 31 and the second channel selection module 32 are respectively connected with an anode input end AHD+ and a cathode input end AHD-of the AHD input port; the first channel selection module 31 comprises a first output end (OUT 1) and a second output end (OUT 2) which are respectively connected with the operational amplifier module 6 and the decoding module 7; the second channel selection module 32 comprises a third output end (OUT 1) and a fourth output end (OUT 2) which are respectively connected with the operational amplifier module 6 and the decoding module 7;
when the control module 1 judges that the negative electrode signal is abnormal according to the abnormality detection signal, the signal output of the second channel selection module 32 is closed, a first gating signal is generated, and the first channel selection module 31 is controlled to gate the first output end;
when the control module 1 judges that the positive signal is abnormal according to the abnormality detection signal, the signal output of the first channel selection module 31 is closed, a first gating signal is generated, and the second channel selection module 32 is controlled to gate the third output end;
when the control module 1 determines that the differential video signal is normal according to the anomaly detection signal, a first gating signal is generated, the first channel selection module 31 is controlled to gate the second output terminal, and the second channel selection module 32 is controlled to gate the fourth output terminal.
IN a further embodiment, the signal selection module 4 comprises a first input (IN 1 port IN fig. 2) and a second input (IN 2 port IN fig. 2) independent of each other; when the positive electrode signal/negative electrode signal is abnormal, the control module 1 generates a second gating signal, and the control signal selecting module 4 gates the second input terminal/first input terminal.
In this embodiment, the first channel selection module 31 and the second channel selection module 32 corresponding to the positive signal input and the negative signal input respectively are provided to establish the path selection module 3, so as to perform targeted adjustment on the output of two paths of signals in the differential video signal, and when one path of signals is abnormal (the positive signal is abnormal or the negative signal is abnormal), the signal output is closed, and the other path of normal signal is output, so that when a certain branch line has a fault, the fault repair recovery signal is timely output.
In a further embodiment, the operational amplifier module 6 is provided with an in-phase amplifying circuit and an anti-phase amplifying circuit, and the in-phase amplifying circuit is connected with the first output end and the first input end; the inverting amplifying circuit is connected with the third output end and the second input end;
the in-phase amplifying circuit is used for in-phase amplifying the positive electrode signal;
the inverting amplification circuit is used for inverting amplification of the negative electrode signal.
The operational amplifier module 6 comprising the in-phase amplifying circuit and the anti-phase amplifying circuit is arranged, so that the positive electrode signal and the negative electrode signal can be compatible, and when a signal fault occurs, the positive electrode signal/the negative electrode signal is subjected to in-phase amplifying/anti-phase amplifying to obtain the positive electrode signal meeting the decoding condition of the decoding module 7, and the positive electrode signal can be directly input into the decoding module 7 for analysis.
In this embodiment, the amplification factor of the operational amplifier module 6 is determined according to the ratio of the signal amplitude required for normal decoding by the decoding module 7 to the single-ended signal (positive signal or negative signal in the differential video signal) at that time. The amplification factor is preferably 2 in this embodiment so that the single-ended signal can reach the amplitude of a conventional differential video signal.
In a further embodiment, the fault isolation module 5 is a switching circuit, the control end of which is connected to the control module 1, and the signal input end is connected to the second output end and the fourth output end.
The fault isolation module 5 includes a switching tube Q1, a switching tube Q2, and resistors R1 to R4, and in this embodiment, the switching tube Q1 is preferably an N-channel MOS tube, and the switching tube Q2 is preferably an NPN transistor.
The drain electrode D of the switch tube Q1 is used as a signal input end to be connected between the fourth output end and the decoding module 7, and is also connected between the second output end and the decoding module 7 through a resistor R5, the source electrode S is grounded, the grid electrode G is connected with a power supply (12V is selected in the embodiment) through a resistor R1, and one end of the resistor R2 is connected with the grid electrode G, and the other end is connected with the source electrode S;
the collector of the switch tube Q2 is connected with the grid G of the switch tube Q1, the emitter is grounded, the base is connected to the control module 1 through the resistor R3 as the control end, one end of the resistor R2 is connected with the base, and the other end is connected with the emitter.
When the control end receives a high level, the switching tube Q2 is turned on, and the switching tube Q1 is turned off; when the control end receives low level, the switch tube Q2 is closed, and the switch tube Q1 is conducted.
When the control end receives the isolation signal, the signal input end and the grounding end are conducted, and the signal connection between the decoding module 7 and the path selection module 3 is disconnected.
The fault isolation module 5 with the switching characteristic is designed in this embodiment, the signal input end is arranged at the connection point between the path selection module 3 and the decoding module 7, when a signal fault occurs, the signal input end and the grounding end are conducted in response to the isolated signal, so that the second output end of the first channel selection module 31 and the fourth output end of the first channel selection module 31 are grounded, the signal interference of the fault line to the decoding module 7 is isolated, and meanwhile, the reference ground is provided for the single-ended signal output by the signal selection module 4.
The embodiment of the invention is provided with the feature extraction module 2, and the differential video signal input by the AHD input port is directly subjected to feature acquisition to obtain an abnormal detection signal, and the abnormal detection is carried out at the beginning of signal input, so that the generation of the abnormal signal (fault generation) can be quickly reacted and the fault repair can be carried out; the path selection module 3 is arranged to match with the double paths of the fault restoration loop (the operational amplifier module 6+the signal selection module 4+the decoding module 7) and the normal output loop (the decoding module 7), when the signals are abnormal, the path selection module is switched to the fault restoration loop, and the signal amplification function of the operational amplifier module 6 is utilized to amplify the single-ended signal (the positive signal or the negative signal) to a preset amplitude value, so that the working requirement of the decoding module 7 is met, the normal transmission of video signals is maintained, and the reliability of the differential video signal transmission system is further improved.
Example 2
The invention also provides a differential video transmission method, which adopts the differential video transmission device provided by the embodiment 1, referring to fig. 3, and comprises the steps of S1-S3:
s1, acquiring a differential video signal and judging whether the differential video signal is abnormal or not, wherein the method comprises the following steps of S11 to S13:
s11, obtaining a differential video signal in a timing time t and the number M0 of theoretical synchronizing signals;
s12, calculating the first synchronous signal quantity M1 of positive signals and the second synchronous signal quantity M2 of negative signals in the differential video signals within the timing time t;
s13, respectively comparing the first synchronization signal number M1 and the second synchronization signal number M2 by taking the theoretical synchronization signal number M0 as a standard, and if the comparison difference value is larger than a preset threshold value M, representing signal abnormality, wherein the specific table 1 is as follows:
| sequence number | M1 | M2 | Functional status |
| 1 | M0-m<M1 | M0-m<M2 | AHD+ normal, AHD-normal |
| 2 | M0-m<M1 | M0-m>M2 | AHD+ is normal and AHD-is abnormal |
| 3 | M0-m>M1 | M0-m<M2 | AHD+ abnormality, AHD-normal |
| 4 | M0-m>M1 | M0-m>M2 | AHD+ abnormality, AHD-abnormality |
TABLE 1
The theoretical synchronization signal number M0 is the product of the timing time t and the frequency of the differential video signal.
In this embodiment, the theoretical synchronization signal number M0 in the timing time t is taken as a standard, and the difference value calculation and the threshold value comparison are performed by acquiring the first synchronization signal number M1 and the second synchronization signal number M2 corresponding to the positive electrode signal and the negative electrode signal respectively, so that whether the line fault problem of signal abnormality exists can be clearly determined.
S2, when the difference video signal is abnormal, isolating a fault line, controlling a normal line to restore output according to a preset fault restoration strategy, and sending out prompt information of the difference video signal abnormality. The method specifically comprises the following steps:
in one embodiment, step S2 includes steps S21a to S22a:
s21a, when negative electrode signals in the differential video signals are abnormal, in-phase amplifying the input positive electrode signals to a preset amplitude value, and inputting the amplified single-ended signals to a first input end of a signal selection module 4;
s22a, disconnecting the output of the negative electrode signal and sending out prompt information of abnormality of the negative electrode signal.
In another embodiment, step S2 includes steps S21b to S22b:
s21b, when positive electrode signals in the differential video signals are abnormal, carrying out reverse phase amplification on the input negative electrode signals to a preset amplitude value, and inputting the amplified single-ended signals to a second input end of the signal selection module 4;
s22b, disconnecting the output of the positive electrode signal and sending out prompt information of abnormality of the positive electrode signal.
In yet another embodiment, step S2 includes steps S21c to S22c:
s21c, when the positive electrode signal and the negative electrode signal are judged to be abnormal at the same time, the output of the positive electrode signal and the negative electrode signal in the differential video signal is disconnected;
s22c, sending out prompt information that the positive electrode signal and the negative electrode signal are abnormal at the same time.
In the embodiment, corresponding fault coping strategies are designed aiming at different abnormal conditions of differential video signals, when only one path of signal is abnormal (positive signal or negative signal is abnormal), the negative signal/positive signal which is still normally output by the other path is amplified in opposite phase or in same phase until the rest single-ended signal can meet the preset amplitude of the decoding module 7, so that the video signal is stably output; when the positive electrode signal and the negative electrode signal are abnormal at the same time, the output of the positive electrode signal and the negative electrode signal in the differential video signal is directly disconnected, so that unnecessary resource waste and secondary circuit damage are reduced; the signal abnormality prompt is utilized to remind workers of repairing faults in time.
And S3, when the difference video signal is not judged to be abnormal, the difference video signal is controlled to be directly output to the decoding module 7 for decoding.
The embodiment of the invention configures a corresponding fault repairing method for the fault repairing system, detects the state of the differential video signal in real time, isolates the fault line at the first time after detecting abnormal signal transmission, and controls the normal line to recover output according to the fault repairing strategy, so that the differential video signal can still be normally transmitted after the signal fault occurs, and the reliability of the differential video signal output system is further improved.
Referring to fig. 2 and 3, in this embodiment, the fault repairing system works as follows:
the feature extraction module 2 is provided with two video synchronization signal extraction modules U1 and U2, which are respectively connected to the ahd+, AHD-, collect positive signals and negative signals (i.e. abnormal detection signals) and upload the positive signals and the negative signals to the MCU (respectively upload the positive signals and the negative signals to the counting ports mcu_tz1 and mcu_tz2 of the MCU), and count the number M1 of the first synchronization signals and the number M2 of the second synchronization signals by using the external counting function of the MCU.
At this time, the abnormality judgment is entered, the theoretical synchronization signal number M0 is compared with the first synchronization signal number M1 and the second synchronization signal number M2, and whether the abnormality occurs or not is confirmed according to the magnitude relation between the comparison difference and the preset threshold M (see table 1 for details).
(1) When both AHD+ and AHD-are in normal state (i.e. the differential video signal is normal)
The MCU enables the first channel selection module 31 and the second channel selection module 32, so that the first channel selection module 31 and the second channel selection module 32 enter a working state.
Then, the MCU outputs a first gating signal according to the normal judgment of the differential video signal, and controls the first channel selection module 31 and the second channel selection module 32 to gate to OUT2 (namely a second output end and a fourth output end) so that the positive electrode signal and the negative electrode signal of the differential video signal are directly connected to the VINP end and the VINN end of the decoding module 7 for decoding; and outputs a high level to the control end MCU_CRT of the fault isolation module 5 to control the switching tube Q1 to be in a closed state.
(2) When AHD+ is in normal state and AHD-is in abnormal state (i.e. positive signal is normal and negative signal is abnormal)
The MCU enables the first channel selection module 31 and outputs a first gating signal to control the first channel selection module 31 to gate to OUT1 (namely a first output end), and outputs a positive electrode signal to an in-phase amplifying circuit of the operational amplifier module 6; turning off the enabling of the second channel selection module 32, i.e. turning off the signal output of the second channel selection module 32; and sends out the abnormal prompt message of the negative electrode signal.
The in-phase amplifying circuit amplifies the positive electrode signal to a forward single-ended signal with a preset amplitude in an in-phase mode according to a preset fault restoration strategy, and outputs the positive electrode signal to the signal selecting module 4.
The signal selection module 4 at this time receives the forward single-ended signal from the IN1 port and outputs the signal to the decoding module 7U4 for decoding, because the signal selection module receives the second strobe signal (which is the strobe first input terminal at this time) sent by the MCU.
Meanwhile, the MCU outputs a high level to the control end mcu_crt of the fault isolation module 5, controls the switching tube Q2 to be in a closed state, connects the second output end and the fourth output end to the ground, and provides a reference ground to the single-ended signal.
(3) When the AHD+ is in an abnormal state and the AHD-is in a normal state (i.e. the positive signal is abnormal and the negative signal is normal)
The MCU enables the second channel selection module 32 and outputs a first gating signal to control the second channel selection module 32U7 to gate to OUT1 (namely a third output end), and outputs a negative electrode signal to an inverting amplifier circuit of the operational amplifier module 6; turning off the enabling of the first channel selection module 31, i.e. turning off the signal output of the first channel selection module 31; and sends out the abnormal prompt information of the positive electrode signal.
The inverting amplification circuit performs inverting amplification on the negative electrode signal to a forward single-ended signal with a preset amplitude according to a preset fault restoration strategy, and outputs the positive single-ended signal to the signal selection module 4.
The signal selecting module 4 at this time receives the forward single-ended signal received by the IN2 port and outputs the forward single-ended signal to the decoding module 7 for decoding, because the second gating signal (the gating second input terminal at this time) sent by the MCU is received.
Meanwhile, the MCU outputs a high level to the control end mcu_crt of the fault isolation module 5, controls the switching tube Q2 to be in a closed state, connects the second output end and the fourth output end to the ground, and provides a reference ground to the single-ended signal.
(4) When both AHD+ and AHD-are in abnormal state (i.e. both positive signal and negative signal are abnormal)
The MCU closes the enabling of the first channel selection module 31 and the second channel selection module 32, and sends out prompt information that the positive electrode signal and the negative electrode signal are abnormal at the same time.
The above examples are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above examples, and any other changes, modifications, substitutions, combinations, and simplifications that do not depart from the spirit and principle of the present invention should be made in the equivalent manner, and the embodiments are included in the protection scope of the present invention.
Claims (11)
1. A differential video transmission device, characterized by: the system comprises a control module, a characteristic extraction module, a path selection module, a signal selection module, a fault isolation module, an operational amplifier module and a decoding module, wherein the characteristic extraction module, the path selection module, the signal selection module and the fault isolation module are connected with the control module; the fault isolation module is respectively connected with the path selection module and the decoding module;
the characteristic extraction module is connected with the AHD input port and is used for carrying out characteristic extraction on the differential video signal to obtain an abnormal detection signal;
the control module is used for generating a corresponding gating signal according to the abnormality detection signal, controlling the signal gating of the path selection module and the signal selection module, generating an isolation signal and sending the isolation signal to the fault isolation module;
the fault isolation module is used for responding to the isolation signal to isolate a fault line;
the path selection module is connected with an AHD input port and is used for responding to the gating signal and controlling the differential video signal to be output to the operational amplifier module or the decoding module;
the operational amplifier module is used for amplifying the positive signal or the negative signal of the differential video signal according to a preset fault restoration strategy; specifically, when the negative electrode signal in the differential video signal is abnormal, the input positive electrode signal is amplified in phase to a preset amplitude value; when the positive signal in the differential video signal is judged to be abnormal, carrying out reverse amplification on the input negative signal to a preset amplitude value;
the signal selection module is used for responding to the gating signal, gating the output end of the operational amplifier module and outputting a corresponding single-ended signal to the decoding module;
the decoding module is used for receiving the differential video signal or the single-ended signal and decoding.
2. A differential video transmission apparatus as defined in claim 1, wherein: the path selection module comprises a first channel selection module and a second channel selection module; the first channel selection module and the second channel selection module are respectively connected with the positive electrode input end and the negative electrode input end of the AHD input port; the first channel selection module comprises a first output end and a second output end which are respectively connected with the operational amplifier module and the decoding module; the second channel selection module comprises a third output end and a fourth output end which are respectively connected with the operational amplifier module and the decoding module;
when the control module judges that the negative electrode signal is abnormal according to the abnormality detection signal, the signal output of the second channel selection module is closed, a first gating signal is generated, and the first channel selection module is controlled to gate a first output end;
when the control module judges that the positive signal is abnormal according to the abnormality detection signal, the signal output of the first channel selection module is closed, the first gating signal is generated, and the second channel selection module is controlled to gate a third output end;
when the control module judges that the differential video signal is normal according to the abnormality detection signal, the control module generates the first gating signal, controls the first channel selection module to gate the second output end and controls the second channel selection module to gate the fourth output end.
3. A differential video transmission apparatus as defined in claim 2, wherein: the signal selection module comprises a first input end and a second input end which are mutually independent; when the positive electrode signal/the negative electrode signal is abnormal, the control module generates a second gating signal to control the signal selection module to gate the second input end/the first input end.
4. A differential video transmission apparatus as claimed in claim 3, wherein: the operational amplifier module is provided with an in-phase amplifying circuit and an anti-phase amplifying circuit, and the in-phase amplifying circuit is connected with the first output end and the first input end; the inverting amplification circuit is connected with the third output end and the second input end;
the in-phase amplifying circuit is used for in-phase amplifying the positive electrode signal;
the inverting amplification circuit is used for inverting amplification of the negative electrode signal.
5. A differential video transmission apparatus as defined in claim 2, wherein: the fault isolation module is a switch circuit, a control end of the fault isolation module is connected with the control module, and a signal input end of the fault isolation module is connected with the second output end and the fourth output end;
and when the control end receives the isolation signal, the signal input end and the grounding end are conducted, and the signal connection between the decoding module and the path selection module is disconnected.
6. A differential video transmission method employing a differential video transmission apparatus as claimed in any one of claims 1 to 5, comprising the steps of:
s1, acquiring a differential video signal and judging whether the differential video signal is abnormal or not;
and S2, when the differential video signal is abnormal, isolating a fault line, controlling a normal line to recover to output according to a preset fault repair strategy, and sending out prompt information of the abnormal differential video signal.
7. The method of differential video transmission according to claim 6, wherein the step S1 comprises:
s11, obtaining differential video signals in timing time and the number of theoretical synchronous signals;
s12, calculating the number of first synchronous signals of positive signals and the number of second synchronous signals of negative signals in the differential video signals in the timing time;
s13, respectively comparing the first synchronous signal quantity and the second synchronous signal quantity by taking the theoretical synchronous signal quantity as a standard, and if the comparison difference value is larger than a preset threshold value, representing signal abnormality.
8. The method of differential video transmission according to claim 6, wherein said step S2 comprises:
s21a, when negative electrode signals in the differential video signals are abnormal, in-phase amplifying the input positive electrode signals to a preset amplitude value, and inputting the amplified single-ended signals to a first input end of a signal selection module;
s22a, disconnecting the output of the negative electrode signal and sending out prompt information of abnormality of the negative electrode signal.
9. The method of differential video transmission according to claim 6, wherein said step S2 comprises:
s21b, when positive signals in the differential video signals are abnormal, carrying out reverse amplification on the input negative signals to a preset amplitude value, and inputting the amplified single-ended signals to a second input end of a signal selection module;
s22b, disconnecting the output of the positive electrode signal and sending out prompt information of abnormality of the positive electrode signal.
10. The method of differential video transmission according to claim 6, wherein said step S2 comprises:
s21c, when the positive electrode signal and the negative electrode signal are judged to be abnormal at the same time, disconnecting the output of the positive electrode signal and the negative electrode signal in the differential video signal;
s22c, sending out prompt information that the positive electrode signal and the negative electrode signal are abnormal at the same time.
11. The differential video transmission method as claimed in claim 6, further comprising the steps of:
and S3, when the difference video signal is not judged to be abnormal, controlling the difference video signal to be directly output to a decoding module for decoding.
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001016143A (en) * | 1999-06-28 | 2001-01-19 | Japan Aviation Electronics Industry Ltd | Differential signal communication abnormality monitoring circuit |
| CN200959622Y (en) * | 2006-07-31 | 2007-10-10 | 华为技术有限公司 | Difference signal transmission line detecting system |
| EP1892960A2 (en) * | 2006-08-25 | 2008-02-27 | Samsung Electronics Co., Ltd. | Repeater Apparatus Linking Video Acquirement Apparatus and Video Recording Apparatus using Unshielded Twisted Pair Cable |
| CN101630496A (en) * | 2009-03-13 | 2010-01-20 | 深圳市优特普科技有限公司 | Twisted-pair visual frequency or audio frequency signal transmission system with automatic regulation |
| JP2012222416A (en) * | 2011-04-05 | 2012-11-12 | Nec Corp | Differential signal failure detection device and differential signal failure detection method |
| JP2014154936A (en) * | 2013-02-05 | 2014-08-25 | Ricoh Co Ltd | Differential signal receiver, image forming apparatus including differential signal receiver, and differential signal receiving method |
| JP2018031675A (en) * | 2016-08-24 | 2018-03-01 | 旭化成エレクトロニクス株式会社 | Current interface circuit |
| CN110341754A (en) * | 2019-07-29 | 2019-10-18 | 郑州铁路职业技术学院 | A kind of point machine indication rod fault monitoring system |
| CN110930914A (en) * | 2019-12-17 | 2020-03-27 | 京东方科技集团股份有限公司 | Signal detection circuit, signal detection method and display device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102008022497A1 (en) * | 2007-05-15 | 2008-11-20 | Denso Corp., Kariya-shi | Load control device and associated method for processing a diagnostic signal |
| EP2728899A4 (en) * | 2011-10-20 | 2014-09-03 | Huawei Device Co Ltd | Multi-purpose connector for multiplexing headset interface into high definition video and audio interface and handheld electronic device |
| US11169218B2 (en) * | 2018-12-21 | 2021-11-09 | Analog Devices, Inc. | Current monitor with fault detection |
-
2020
- 2020-12-28 CN CN202011578883.6A patent/CN112689102B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001016143A (en) * | 1999-06-28 | 2001-01-19 | Japan Aviation Electronics Industry Ltd | Differential signal communication abnormality monitoring circuit |
| CN200959622Y (en) * | 2006-07-31 | 2007-10-10 | 华为技术有限公司 | Difference signal transmission line detecting system |
| EP1892960A2 (en) * | 2006-08-25 | 2008-02-27 | Samsung Electronics Co., Ltd. | Repeater Apparatus Linking Video Acquirement Apparatus and Video Recording Apparatus using Unshielded Twisted Pair Cable |
| CN101630496A (en) * | 2009-03-13 | 2010-01-20 | 深圳市优特普科技有限公司 | Twisted-pair visual frequency or audio frequency signal transmission system with automatic regulation |
| JP2012222416A (en) * | 2011-04-05 | 2012-11-12 | Nec Corp | Differential signal failure detection device and differential signal failure detection method |
| JP2014154936A (en) * | 2013-02-05 | 2014-08-25 | Ricoh Co Ltd | Differential signal receiver, image forming apparatus including differential signal receiver, and differential signal receiving method |
| JP2018031675A (en) * | 2016-08-24 | 2018-03-01 | 旭化成エレクトロニクス株式会社 | Current interface circuit |
| CN110341754A (en) * | 2019-07-29 | 2019-10-18 | 郑州铁路职业技术学院 | A kind of point machine indication rod fault monitoring system |
| CN110930914A (en) * | 2019-12-17 | 2020-03-27 | 京东方科技集团股份有限公司 | Signal detection circuit, signal detection method and display device |
Non-Patent Citations (1)
| Title |
|---|
| 一种新型运放相位反转保护电路;汪西虎;吴龙胜;刘佑宝;;半导体学报(09);全文 * |
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