阅读说明：本技术 一种视频信号输出电路及摄像机 (A kind of video signal output circuit and video camera ) 是由 孔超 于 2018-05-25 设计创作，主要内容包括：本发明实施例提供了一种视频信号输出电路及摄像机,应用于视频监控技术领域,所述电路包括：连接了复位按键的视频信号处理主芯片、TVI转换器和BNC接口；复位按键用于在接收到用户的触发操作时,对视频信号处理主芯片的电平进行切换；视频信号处理主芯片用于当自身电平被切换的时长小于预设切换时长,对信号输出格式进行切换,并对MIPI协议的图像信号进行处理,得到并行的视频输出信号或CVBS视频信号；TVI转换器用于对接收的并行的视频输出信号进行转换,得到TVI视频信号；BNC接口用于接收TVI视频信号或CVBS视频信号。本发明通过复位按键控制视频信号输出的格式,使一个BNC接口支持两种视频信号的输出。(The embodiment of the invention provides a kind of video signal output circuit and video cameras, are applied to technical field of video monitoring, the circuit includes: the video frequency signal processing master chip, TVI converter and bnc interface for being connected to reset key；Reset key is used in the trigger action for receiving user, is switched over to the level of video frequency signal processing master chip；The duration that video frequency signal processing master chip is used to be switched when itself level is less than default switching duration, switches over, and handle the picture signal of MIPI agreement to signal output format, obtains parallel video output signals or CVBS vision signal；TVI converter obtains TVI vision signal for converting to received parallel video output signals；Bnc interface is for receiving TVI vision signal or CVBS vision signal.The present invention controls the format of vision signal output by reset key, and a bnc interface is made to support the output of two kinds of vision signals.)

1. a kind of video signal output circuit, which is characterized in that be applied to video camera, the video signal output circuit includes: It is connected to the video frequency signal processing master chip, video transmission interface TVI converter and snap-fit connector BNC of reset key Interface；

The reset key, in the trigger action for receiving user, to the level of the video frequency signal processing master chip It switches over；

The video frequency signal processing master chip, the duration for being switched when itself level is less than default switching duration, and is believing When number output format is TVI vision signal, the signal output format of the video frequency signal processing master chip is switched to compound view Frequency broadcast singal CVBS vision signal；Or, when the duration that itself level is switched is less than the default switching duration, and in signal When output format is CVBS vision signal, the signal output format of the video frequency signal processing master chip is switched to TVI video Signal；

The video frequency signal processing master chip is also used to when signal output format is TVI vision signal, to received mobile production The picture signal of industry processor interface MIPI agreement is handled, and is obtained parallel video output signals and is exported to the TVI turns Parallel operation；Or, handling the picture signal of received MIPI agreement, obtaining when signal output format is CVBS vision signal It exports to CVBS vision signal to the bnc interface；

The TVI converter, for the signal output format in the video frequency signal processing master chip be TVI vision signal when, The parallel video output signals for receiving video frequency signal processing master chip output, to the parallel video output signals into Row conversion, obtains TVI vision signal and exports to the bnc interface；

The bnc interface, for the signal output format in the video frequency signal processing master chip be TVI vision signal when, connect The TVI vision signal for receiving the TVI converter output is exported to outside；Or, in the signal of the video frequency signal processing master chip When output format is CVBS vision signal, the CVBS vision signal for receiving the video frequency signal processing master chip output is exported to outer Portion.

2. video signal output circuit according to claim 1, which is characterized in that the video signal output circuit also wraps It includes: selected on-off circuit；

The video frequency signal processing master chip is further used for after executing the switching of signal output format, switchs to the selection Circuit sends configuration switching signal；

The selected on-off circuit, for being switched to TVI video letter in signal output format according to the configuration switching signal Number when, the TVI vision signal for receiving TVI converter output is exported to the bnc interface；Or, in signal output format quilt When being switched to CVBS vision signal, the CVBS vision signal for receiving the video frequency signal processing master chip output is exported to described Bnc interface.

3. video signal output circuit according to claim 2, which is characterized in that the video signal output circuit also wraps It includes:

TVI video signal driver is set between the selected on-off circuit and the TVI converter, for described TVI converter output TVI vision signal carry out video filtering amplification, the TVI vision signal after obtaining filter and amplification export to Selected on-off circuit.

4. video signal output circuit according to claim 3, which is characterized in that the video signal output circuit also wraps It includes:

CVBS video filtering amplifier is set between the selected on-off circuit and the video frequency signal processing master chip, is used It is filtered amplification in the CVBS vision signal exported to the video frequency signal processing master chip, the CVBS after obtaining filter and amplification Vision signal is exported to the selected on-off circuit.

5. video signal output circuit according to claim 4, which is characterized in that the selected on-off circuit, comprising: one A control port, two input ports and an output port；

The control port is connected with the video frequency signal processing master chip, for receiving the video frequency signal processing master chip hair The configuration switching signal sent；

An input port in described two input ports is connected with the TVI video signal driver, for described When the signal output format of video frequency signal processing master chip is TVI vision signal, accept filter amplified TVI vision signal； Another input port is connected with the CVBS video filtering amplifier, for the signal in the video frequency signal processing master chip When output format is CVBS vision signal, accept filter amplified CVBS vision signal；

The output port is connected with the bnc interface, for being regarded the TVI after filter and amplification according to the configuration switching signal CVBS vision signal after frequency signal or filter and amplification is exported to the bnc interface.

6. video signal output circuit according to claim 4, which is characterized in that the TVI video signal driver Including two TVI video filtering amplifiers, and two TVI video filtering amplifier serial connections, a TVI video filtering are put Big device is connect with the TVI converter, another TVI video filtering amplifier is connect with the selected on-off circuit.

7. video signal output circuit according to claim 1, which is characterized in that the video frequency signal processing master chip by Digital Signal Processing dsp chip realize, the video frequency signal processing master chip include: main control module, video output VO module and CVBS module；

The main control module, for controlling the VO module to received MIPI when signal output format is TVI vision signal The picture signal of agreement is handled, and is obtained parallel video output signals and is exported to the TVI converter；Or, defeated in signal When format is CVBS vision signal out, controls the CVBS module and the picture signal of received MIPI agreement is handled, obtain It exports to CVBS vision signal to the bnc interface.

8. video signal output circuit according to claim 1, which is characterized in that the video frequency signal processing master chip is logical It crosses BT1120 agreement and the parallel video output signals is sent to the TVI converter.

9. video signal output circuit according to claim 1, which is characterized in that the video frequency signal processing master chip, It is also used to reset the video camera when the duration that itself level is switched is not less than the default switching duration.

10. a kind of video camera characterized by comprising imaging sensor and video according to any one of claims 1 to 9 letter Number output circuit；

Described image sensor obtains mobile industry processor interface MIPI agreement for handling the optical signal of acquisition Picture signal, and the picture signal of the MIPI agreement is exported to the video frequency signal processing of the video signal output circuit Master chip.

Technical field

The present invention relates to technical field of video monitoring, more particularly to a kind of video signal output circuit and video camera.

Background technique

In technical field of video monitoring, IPC (Internet Protocol Camera, web camera) equipment is a kind of By traditional cameras, generated a new generation's video camera, current IPC equipment support network output, CVBS in conjunction with network technology (Composite Video Broadcast Signal, Composite Video Baseband Signal) output or HD-TVI (High Definition Transport Video Interface, HD video coffret) it exports, HD-TVI is referred to as TVI.

Single video transmission technologies based on BNC (Bayonet Nut Connector, snap-fit connector) interface In, a bnc interface of IPC equipment can only export one of TVI vision signal or CVBS vision signal vision signal.

In fact, the vision signal output format of bnc interface has been configured in IPC equipment production process, Yong Hu It cannot be modified in use process, that is to say, that in use, the vision signal output format of bnc interface is cannot It is switched between two kinds of vision signals.Therefore, an existing bnc interface can only actually support TVI vision signal or The output of one of CVBS vision signal vision signal.In this way, if user uses the IPC of only one bnc interface Equipment then needs to set using the IPC of another different output formats when needing to obtain the vision signal of another format It is standby, higher cost.

As it can be seen that how to realize that a bnc interface supports two kinds of vision signals of TVI and CVBS in user's use process The problem of output is urgent need to resolve.

Summary of the invention

The embodiment of the present invention is designed to provide a kind of video signal output circuit and video camera, to realize a BNC Interface supports the output of two kinds of vision signals.Specific technical solution is as follows:

The embodiment of the invention provides a kind of video signal output circuits, are applied to video camera, the vision signal output Circuit includes: the video frequency signal processing master chip, TVI converter and bnc interface for being connected to reset key；

The reset key, in the trigger action for receiving user, to the video frequency signal processing master chip Level switches over；

The video frequency signal processing master chip, the duration for being switched when itself level are less than default switching duration, and When signal output format is TVI vision signal, the signal output format of the video frequency signal processing master chip is switched to multiple Close video broadcast signal CVBS vision signal；Or, the duration being switched when itself level is less than the default switching duration, and When signal output format is CVBS vision signal, the signal output format of the video frequency signal processing master chip is switched to TVI Vision signal；

The video frequency signal processing master chip is also used to when signal output format is TVI vision signal, to received shifting The picture signal of dynamic Industry Processor Interface MIPI agreement is handled, and is obtained parallel video output signals and is exported to described TVI converter；Or, when signal output format is CVBS vision signal, at the picture signal of received MIPI agreement Reason, obtains CVBS vision signal and exports to the bnc interface；

The TVI converter is TVI vision signal for the signal output format in the video frequency signal processing master chip When, the parallel video output signals of the video frequency signal processing master chip output are received, letter is exported to the parallel video It number is converted, obtains TVI vision signal and export to the bnc interface；

The bnc interface is TVI vision signal for the signal output format in the video frequency signal processing master chip When, the TVI vision signal for receiving the TVI converter output is exported to outside；Or, in the video frequency signal processing master chip When signal output format is CVBS vision signal, the CVBS vision signal output of the video frequency signal processing master chip output is received To outside.

Optionally, the video signal output circuit further include: selected on-off circuit；

The video frequency signal processing master chip is further used for after executing the switching of signal output format, to the selection Switching circuit sends configuration switching signal；

The selected on-off circuit, for being switched to TVI view in signal output format according to the configuration switching signal When frequency signal, the TVI vision signal for receiving the TVI converter output is exported to the bnc interface；Or, exporting lattice in signal When formula is switched to CVBS vision signal, the CVBS vision signal for receiving the video frequency signal processing master chip output is exported to institute State bnc interface.

Optionally, the video signal output circuit further include:

TVI video signal driver is set between the selected on-off circuit and the TVI converter, for pair The TVI vision signal of the TVI converter output carries out video filtering amplification, and the TVI vision signal after obtaining filter and amplification is defeated Out to selected on-off circuit.

Optionally, the video signal output circuit further include:

CVBS video filtering amplifier, be set to the selected on-off circuit and the video frequency signal processing master chip it Between, the CVBS vision signal for exporting to the video frequency signal processing master chip is filtered amplification, after obtaining filter and amplification CVBS vision signal export to the selected on-off circuit.

Optionally, the selected on-off circuit a, comprising: control port, two input ports and an output port；

The control port is connected with the video frequency signal processing master chip, for receiving the video frequency signal processing main core The configuration switching signal that piece is sent；

An input port in described two input ports is connected with the TVI video signal driver, is used for When the signal output format of the video frequency signal processing master chip is TVI vision signal, accept filter amplified TVI video letter Number；Another input port is connected with the CVBS video filtering amplifier, in the video frequency signal processing master chip When signal output format is CVBS vision signal, accept filter amplified CVBS vision signal；

The output port is connected with the bnc interface, for will be after filter and amplification according to the configuration switching signal CVBS vision signal after TVI vision signal or filter and amplification is exported to the bnc interface.

Optionally, the TVI video signal driver includes two TVI video filtering amplifiers, and two TVI views The serial connection of frequency filter amplifier, a TVI video filtering amplifier are connect with the TVI converter, the filter of another TVI video Twt amplifier is connect with the selected on-off circuit.

Optionally, the video frequency signal processing master chip is realized by Digital Signal Processing dsp chip, at the vision signal Reason master chip includes: main control module, video output VO module and CVBS module；

The main control module, for controlling the VO module to received when signal output format is TVI vision signal The picture signal of MIPI agreement is handled, and is obtained parallel video output signals and is exported to the TVI converter；Or, believing When number output format is CVBS vision signal, control the CVBS module to the picture signal of received MIPI agreement at Reason, obtains CVBS vision signal and exports to the bnc interface.

Optionally, the video frequency signal processing master chip is sent out the parallel video output signals by BT1120 agreement It send to the TVI converter.

Optionally, the video frequency signal processing master chip, the duration for being also used to be switched when itself level are not less than described When default switching duration, the video camera is resetted.

The embodiment of the invention provides a kind of video cameras, comprising: imaging sensor and video described in any of the above embodiments letter Number output circuit；

Described image sensor obtains the picture signal of MIPI agreement, and will for handling the optical signal of acquisition The picture signal of the MIPI agreement is exported to the video frequency signal processing master chip of the video signal output circuit.

Video signal output circuit and video camera provided in an embodiment of the present invention, comprising: be connected to the video of reset key Signal processing main chip, TVI converter and bnc interface；Reset key, in the trigger action for receiving user, to view The level of audio signalprocessing master chip switches over；Video frequency signal processing master chip, the duration for being switched when itself level Less than default switching duration, signal output format is switched over；Video frequency signal processing master chip is also used to export lattice in signal When formula is TVI vision signal or CVBS vision signal, the picture signal of received MIPI agreement is handled, is obtained parallel Video output signals or CVBS vision signal；TVI converter is parallel for exporting to received video frequency signal processing master chip Video output signals converted, obtain TVI vision signal；Bnc interface is used to receive the TVI video of TVI converter output Signal is exported to outside；Or it receives the CVBS vision signal that video frequency signal processing master chip exports and exports to outside.The present invention is real Example is applied by the multiplexing to reset key, i.e., the triggering duration of reset key is determined and executes signal output format according to user Switching resets video camera, realizes and switches bnc interface output vision signal by video frequency signal processing master chip Format, so that the output of two kinds of vision signals can be supported by realizing a bnc interface.Certainly, implement any production of the invention Product or method do not necessarily require achieving all the advantages described above at the same time.

Detailed description of the invention

In order to more clearly explain the embodiment of the invention or the technical proposal in the existing technology, to embodiment or will show below There is attached drawing needed in technical description to be briefly described, it should be apparent that, the accompanying drawings in the following description is only this Some embodiments of invention for those of ordinary skill in the art without creative efforts, can be with It obtains other drawings based on these drawings.

Fig. 1 is a kind of structure chart of the video signal output circuit of the embodiment of the present invention；

Fig. 2 is the process that video frequency signal processing master chip carries out the switching of vision signal output format in the embodiment of the present invention Figure；

Fig. 3 is another structure chart of the video signal output circuit of the embodiment of the present invention；

Fig. 4 is another structure chart of the video signal output circuit of the embodiment of the present invention；

Fig. 5 is the two stage filter amplification treatment circuit structure chart of the embodiment of the present invention；

Fig. 6 is the circuit structure diagram of CVBS video filtering amplifier in the embodiment of the present invention；

Fig. 7 is the selected on-off circuit structure chart of the embodiment of the present invention；

Fig. 8 is the pin connection schematic diagram of TP2801 chip；

Fig. 9 is the structure chart of the video camera of the embodiment of the present invention.

Specific embodiment

Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete Site preparation description, it is clear that described embodiments are only a part of the embodiments of the present invention, instead of all the embodiments.It is based on Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other Embodiment shall fall within the protection scope of the present invention.

In order to solve in the prior art, user use video camera during, a bnc interface cannot support TVI and The problem of CVBS two kinds of vision signals output, the embodiment of the invention provides a kind of video signal output circuit and video camera, with Realize that a bnc interface supports the output of two kinds of vision signals.

Video signal output circuit is provided for the embodiments of the invention first below to describe in detail.

Referring to Fig. 1, Fig. 1 is a kind of structure chart of the video signal output circuit of the embodiment of the present invention, is applied to video camera, Video camera includes: IPC equipment and analog video camera, and video signal output circuit includes: video frequency signal processing master chip 100, answers Position key 200, TVI converter 300 and bnc interface 400；Wherein, video frequency signal processing master chip 100 and 200 phase of reset key Even, TVI converter 300 is connected with bnc interface 400, and TVI converter 300 is connected with bnc interface 400.

Reset key 200, in the trigger action for receiving user, to the electricity of video frequency signal processing master chip 100 It is flat to switch over；

Video frequency signal processing master chip 100, the duration for being switched when itself level, which is less than, presets switching duration, and When signal output format is TVI vision signal, the signal output format of video frequency signal processing master chip 100 is switched to CVBS view Frequency signal；Or, being CVBS video letter when the duration that itself level is switched is less than default switching duration, and in signal output format Number when, the signal output format of video frequency signal processing master chip 100 is switched to TVI vision signal；

Video frequency signal processing master chip 100 is also used to when signal output format is TVI vision signal, to received The picture signal of MIPI (Mobile Industry Processor Interface, mobile industry processor interface) agreement into Row processing, obtains parallel video output signals and exports to TVI converter 300；Or, being CVBS video letter in signal output format Number when, the picture signal of received MIPI agreement is handled, CVBS vision signal is obtained and exports to bnc interface 400；

TVI converter 300 is TVI vision signal for the signal output format in video frequency signal processing master chip 100 When, the parallel video output signals of video frequency signal processing master chip output are received, parallel video output signals are turned It changes, obtains TVI vision signal and export to bnc interface 400；

Bnc interface 400, for the signal output format in video frequency signal processing master chip 100 be TVI vision signal when, The TVI vision signal that TVI converter 300 exports is received to export to outside；Or, in the signal of video frequency signal processing master chip 100 When output format is CVBS vision signal, receives the CVBS vision signal that video frequency signal processing master chip 100 exports and export to outer Portion.

In the video signal output circuit of the embodiment of the present invention, reset key 200, in the triggering behaviour for receiving user When making, the level of video frequency signal processing master chip 100 is switched over；Video frequency signal processing master chip 100 is used for when itself electricity The flat duration being switched is less than default switching duration, switches over to signal output format；Video frequency signal processing master chip 100 is also For when signal output format is TVI vision signal or CVBS vision signal, to the picture signal of received MIPI agreement into Row processing, obtains parallel video output signals or CVBS vision signal；TVI converter 300 is used for received vision signal The parallel video output signals that processing main chip 100 exports are converted, and TVI vision signal is obtained；Bnc interface 400 is used for The TVI vision signal that TVI converter 300 exports is received to export to outside；Or receive what video frequency signal processing master chip 100 exported CVBS vision signal is exported to outside.The embodiment of the present invention presses reset according to user by the multiplexing to reset key 200 The different trigger actions of key 200 determine and execute the switching of signal output format or reset to video camera, realize and believed by video Number processing main chip 100 switches the format that bnc interface 400 exports vision signal, to realize that a bnc interface 400 can Support the output of two kinds of vision signals.

Video frequency signal processing master chip 100 in embodiment illustrated in fig. 1, can according to user to reset key 200 not Same trigger action determines that executing signal exports lattice when the duration that reset key 200 is triggered by user is less than default switching duration Formula switching；When the duration that reset key 200 is triggered by user is not less than default switching duration, video camera is resetted.Its In, reset key 200 is the reserved Initialize installation reset key of video camera, for initializing to video camera.

Specifically, referring to fig. 2, Fig. 2 is that video frequency signal processing master chip carries out vision signal output in the embodiment of the present invention The flow chart of format switching, includes the following steps:

S201, video camera starting.

S202 reads reset key.

Specifically, video camera is after start-up, reset key is read, video camera is initialized.

S203, judges whether reset key is triggered.

In this step, if user carries out trigger action to reset key, S204 is executed.

S204 starts timing.

By being to be determined to execute the switching of signal output format according to triggering duration of the user to reset key in this present embodiment Or video camera is resetted, specifically, being carried out when reset key is triggered to the level of video frequency signal processing master chip Switching, for example, the level of video frequency signal processing master chip is changed into low level by high level, when user no longer triggers reset key When, the level of video frequency signal processing master chip is changed into high level by low level again.Therefore, reset key is touched in user When hair operation, timing can be carried out according to the level, to obtain the duration that reset key is triggered.Work as vision signal When the duration that the level of processing main chip is switched is less than default switching duration, signal output format is switched over, video is worked as When the duration that the level of signal processing main chip is switched is not less than default switching duration, video camera is resetted.

S205 judges whether to be greater than default triggering duration.

In the embodiment of the present invention, maloperation in order to avoid user to video camera, for example, user accidentally touches reset Key, after starting timing, it is first determined whether be greater than default triggering duration (default triggering duration is usually shorter, for example, A length of 1s when default triggering), if not, showing that user may be maloperation, S202 is re-executed, i.e. reading reset key.Such as Fruit is greater than default triggering duration, executes S206.

S206 judges whether to be less than default switching duration.

Specifically, default switching duration is to execute the maximum time of signal output format switching, which is greater than default touching Duration is sent out, for example, can be 5s.If beyond the default switching duration, show user to the trigger action of reset key when Long overlength resets video camera, re-executes S201 later then executing S209.Otherwise, S207 is executed.

S207 executes the switching of signal output format.

S208 terminates.

For above-mentioned process, for example, video camera default output TVI vision signal, video camera initializes after powering on, depending on Audio signalprocessing master chip 100 handles the picture signal of received MIPI agreement, obtains parallel video output signals Output is to TVI converter 300, output TVI view after TVI converter 300 converts received parallel video output signals Frequency signal.If user trigger reset key 200 when a length of 3s (for example, a length of 1s when default triggering, presets a length of when switching 4s), then the switching of signal output format is executed, CVBS vision signal is exported；If user trigger reset key 200 when it is a length of 5s, video camera will reset, and video camera reinitializes.

By vision signal output format switching flow shown in Fig. 2, video frequency signal processing master chip is realized according to multiple The key duration that is triggered in position determines to distinguish and executes the switching of signal output format or reset to video camera.In this way, resetting Key has the function of except resetting video camera that the vision signal that video camera can also be made to export switches to different formats.

Referring to Fig. 3, Fig. 3 is another structure chart of the video signal output circuit of the embodiment of the present invention, and the present embodiment exists On the basis of embodiment illustrated in fig. 1, between bnc interface 400 and TVI converter 300 and video frequency signal processing master chip 100, increase Add and is provided with selected on-off circuit 500.

Video frequency signal processing master chip 100 in the present embodiment is further used for after executing the switching of signal output format, Configuration switching signal is sent to selected on-off circuit 500.

The selected on-off circuit 500, for being switched to TVI video in signal output format according to configuration switching signal When signal, receives the TVI vision signal that TVI converter 300 exports and export to bnc interface 400；Or, in signal output format quilt When being switched to CVBS vision signal, receives the CVBS vision signal that video frequency signal processing master chip 100 exports and export to bnc interface 400。

In the embodiment of the present invention, if TVI vision signal and video frequency signal processing master chip that TVI converter 300 exports The CVBS vision signal and bnc interface 400 of 100 outputs are directly connected to, and form two cablings, cabling bifurcated will cause MEI The problems such as (Electromagnetic Interference, electromagnetic interference) and impedance mismatch, therefore, implementation shown in Fig. 1 Selected on-off circuit 500 is increased on the basis of example, can only retain a cabling and be connected to bnc interface 400, be can be avoided The problems such as PCB (Printed Circuit Board, printed wiring board) cabling bifurcated, effectively inhibition MEI and impedance mismatch, To realize the lossless output of vision signal.

Referring to fig. 4, Fig. 4 is another structure chart of the video signal output circuit of the embodiment of the present invention, as shown in figure 4, On the basis of the present embodiment embodiment shown in Fig. 3, TVI is provided between selected on-off circuit 500 and TVI converter 300 Video signal driver 600 is provided with CVBS between selected on-off circuit 500 and video frequency signal processing master chip 100 and regards Frequency filter amplifier 700.Wherein,

TVI video signal driver 600, the TVI vision signal for exporting to TVI converter 300 carry out video filter Wave amplification, the TVI vision signal after obtaining filter and amplification are exported to selected on-off circuit 500.

As shown in figure 4, TVI video signal driver 600 may include two TVI video filtering amplifiers, i.e. TVI view Frequency filter amplifier 601 and TVI video filtering amplifier 602, and two TVI video filtering amplifier serial connections, TVI view Frequency filter amplifier 602 is connect with TVI converter 300, and is placed close to TVI converter 300, TVI video filtering amplifier 601 connect with selected on-off circuit 500, and place close to selected on-off circuit 500, certainly, TVI video filtering amplifier Other electronic devices, such as resistance can also be connected between 601 and TVI video filtering amplifier 602.On the one hand, turn close to TVI The High-frequency Interference and low frequency pulsating signal that the TVI video filtering amplifier 602 of parallel operation 300 can inhibit TP2801 chip to export, And be conducive to the signal removing of second level filter amplifier and filtering out for interference wave by amplified signal；On the other hand, Close to selected on-off circuit 500 TVI video filtering amplifier 601 can effectively inhibit in the pcb board in video camera it is too long walk The crosstalk and coupled noise that line introduces.In this way, after two stage filter enhanced processing, can with the vision signal of outputting high quality, It is asked to effectively avoid signal from filtering the bad caused image ripple of unclean or amplification effect, snowflake and color distortion etc. Topic.It is the two stage filter amplification treatment circuit structure chart of the embodiment of the present invention referring to Fig. 5, Fig. 5.As can be seen that from TP2801 core The TVI vision signal of piece output exports TVI_OUT video letter after first order filter and amplification and second level filter and amplification respectively Number, which exports to selected on-off circuit 500.

CVBS video filtering amplifier 700, CVBS vision signal for being exported to video frequency signal processing master chip 100 into Row filter and amplification, the CVBS vision signal after obtaining filter and amplification are exported to selected on-off circuit 500.

Specifically, since the picture quality that the highest frequency of CVBS vision signal is lower and shows is relatively low, the present invention The CVBS vision signal that embodiment can export video frequency signal processing master chip 100 by CVBS video filtering amplifier 700 It is filtered amplification.It is the circuit structure diagram of CVBS video filtering amplifier in the embodiment of the present invention referring to Fig. 6, Fig. 6.As it can be seen that After CVBS_OUT vision signal is inputted the CVBS video filtering amplifier 700, vision signal after obtaining filter and amplification, i.e., CVBS_OUT_BNC vision signal can be inputted bnc interface by selected on-off circuit 500 by CVBS_OUT_BNC vision signal 400.In this way, the CVBS vision signal interference noise of output is effectively inhibited and filtered out, and improve useful signal Quality.

As shown in figure 4, the selected on-off circuit 500 in the present embodiment, comprising: a control port, two input ports With an output port；Control port is connected with video frequency signal processing master chip 100, for receiving video frequency signal processing master chip The 100 configuration switching signals sent；An input port and 600 phase of TVI video signal driver in two input ports Even, for the signal output format in video frequency signal processing master chip 100 be TVI vision signal when, accept filter amplified TVI vision signal；Another input port is connected with CVBS video filtering amplifier 700, in video frequency signal processing main core When the signal output format of piece 100 is CVBS vision signal, accept filter amplified CVBS vision signal；Output port with Bnc interface 400 be connected, for according to configuration switching signal by after filter and amplification TVI vision signal or filter and amplification after CVBS vision signal is exported to bnc interface 400.

It is the selected on-off circuit structure chart of the embodiment of the present invention referring to Fig. 7, Fig. 7, U31 selects end to use 10K resistance (RD22) it is grounded, guarantees default conditions, the capacitor by adding 10uF guarantees level in selected on-off circuit 500 for decoupling Stability.In addition, video frequency signal processing master chip 100 execute signal output format switching after, to selected on-off circuit 500 Configuration switching signal is sent, for example, Model_signal level is drawn high.Selected on-off circuit 500 defaults Model_signal Level is low level, exports TVI vision signal, and the output of CVBS vision signal is switched to when Model_signal level is high.

In the video signal output circuit of the embodiment of the present invention, video frequency signal processing master chip 100 is used to export in signal When format is TVI vision signal or CVBS vision signal, the picture signal of received MIPI agreement is handled, is obtained parallel Video output signals or CVBS vision signal；And according to user to the different trigger actions of reset key 200, determination executes letter The switching of number output format resets video camera；TVI converter 300 is for defeated to received video frequency signal processing master chip Parallel video output signals out are converted, and TVI vision signal is obtained；Positioned at two TVI video filterings of different location Amplifier is respectively used to be filtered TVI vision signal amplification, and CVBS video filtering amplifier is used for CVBS vision signal It is filtered amplification；The TVI vision signal that bnc interface is used to receive the output of TVI converter is exported to outside；Or receive video letter The CVBS vision signal of number processing main chip output is exported to outside.The embodiment of the present invention is by the multiplexing to reset key, i.e., According to user to the triggering duration of reset key, determines and execute the switching of signal output format or video camera is resetted, realize Switch the format that bnc interface 400 exports vision signal by video frequency signal processing master chip 100, to realize that a BNC connects Mouth can support the output of two kinds of vision signals.It can be mentioned by TVI video filtering amplifier and CVBS video filtering amplifier The quality of height output vision signal can only retain a cabling by selection switch 500 and be connected to bnc interface 400, to keep away Exempt from the problems such as PCB trace bifurcated causes MEI and impedance mismatch, realizes the lossless output of vision signal.

Video frequency signal processing master chip 100 in Fig. 4 embodiment can be DSP (Digital Signal Processing, Digital Signal Processing) chip, as shown in figure 4, video frequency signal processing master chip 100, may include: master control mould Block 101, video output VO module 102 and CVBS module 103；Main control module 101, for being TVI video in signal output format When signal, control VO module 102 handles the picture signal of received MIPI agreement, obtains parallel video output signals It exports to TVI converter 300；Or, controlling CVBS module 103 to received when signal output format is CVBS vision signal The picture signal of MIPI agreement is handled, and is obtained CVBS vision signal and is filtered by CVBS video filtering amplifier 700 After amplification, by the selection of selected on-off circuit 500 output to bnc interface 400.

Video frequency signal processing master chip 100 generally includes multiple pins, and the meaning of each pin is as shown in Table 1.

Table one

Video frequency signal processing master chip 100 can directly export CVBS vision signal, and cannot directly export TVI video letter Number.But video frequency signal processing master chip 100 obtains simultaneously after being handled the picture signal of received MIPI agreement Parallel video output signals are exported to TVI converter 300, are obtained by TVI converter 300 by capable video output signals TVI vision signal.

TVI converter 300 in Fig. 4 embodiment is a kind of signal of the serial TVI data of parallel BT1120 protocol data turn Parallel video output signals can be sent to by converter, therefore, video frequency signal processing master chip 100 by BT1120 agreement TVI converter.TVI converter 300 can be TP2801 chip, between TP2801 chip and video frequency signal processing master chip in addition to Outside the communication for carrying out vision signal by BT1120 agreement, IIC (Inter-Integrated Circuit, collection can also be passed through At circuit bus) transmission other information, coaxial cable is transferred to eventually by video output.In addition to this, TP2801 chip The relevant information that can also receive coaxial view control by coaxial cable, is then transferred to vision signal for information is controlled by IIC Processing main chip side.It is the pin connection schematic diagram of TP2801 chip referring to Fig. 8, Fig. 8, each pin is electrical in TP2801 chip Connection can be found in table two.

Table two

It can be seen that pin 11-14,17-20,24-31 are for receiving parallel video output signals (the i.e. parallel port BT1120 Video data), after handling the parallel port BT1120 video data, TVI vision signal is exported by pin 8.In addition, Reseting pin (pin 2) the default level of TP2801 chip is high level, and signal passes through level-one RC (Resistance- Capacitance, resistance-capacitance) filter circuit, 10 ohm of resistance value selection, capacitance selection 100nF avoids electromagnetic interference from believing Number cause reset signal unstable, and then influences vision signal and export quality.Since TP2801 chip belongs to the prior art, herein No longer describe in detail to other pins.

The embodiment of the invention also provides a kind of video cameras, are the knot of the video camera of the embodiment of the present invention referring to Fig. 9, Fig. 9 Composition, comprising: imaging sensor 901 and video signal output circuit 902；Imaging sensor 901, the MIPI association for that will acquire The picture signal of view is exported to the video frequency signal processing master chip of video signal output circuit 902；Video signal output circuit 902 It can be the video signal output circuit in Fig. 1 embodiment, Fig. 3 embodiment or Fig. 4 embodiment.

Wherein, imaging sensor 901 is used to handle the optical signal of acquisition, obtains the picture signal of MIPI agreement, And the picture signal of MIPI agreement is exported to the video frequency signal processing master chip of video signal output circuit 902, vision signal Processing main chip is used to believe the image of MIPI agreement when signal output format is TVI vision signal or CVBS vision signal It number is handled, obtains parallel video output signals or CVBS vision signal；And when according to user to the triggering of reset key It is long, it determines and executes the switching of signal output format or video camera is resetted；TVI converter is used for received vision signal The parallel video output signals of reason master chip output are converted, and TVI vision signal is obtained；Bnc interface turns for receiving TVI The TVI vision signal of parallel operation output is exported to outside；Or the CVBS vision signal of reception video frequency signal processing master chip output is defeated Out to external.

The video signal output circuit of video camera is by the multiplexing to reset key in the embodiment of the present invention, i.e., according to user To the triggering duration of reset key, determines and execute the switching of signal output format or video camera is resetted, realization passes through video Signal processing main chip come switch bnc interface output vision signal format, thus realize a bnc interface can support two kinds The output of vision signal.In this way, can also export two kinds of video letters of TVI and CVBS even if only one bnc interface of video camera Number, when users use, two kinds of vision signals of TVI and CVBS can be switched by the triggering to reset key.Certainly, video camera When exporting vision signal, one of two kinds of vision signals of TVI and CVBS can only be exported.

It should be noted that, in this document, relational terms such as first and second and the like are used merely to a reality Body or operation are distinguished with another entity or operation, are deposited without necessarily requiring or implying between these entities or operation In any actual relationship or order or sequence.Moreover, the terms "include", "comprise" or its any other variant are intended to Non-exclusive inclusion, so that the process, method, article or equipment including a series of elements is not only wanted including those Element, but also including other elements that are not explicitly listed, or further include for this process, method, article or equipment Intrinsic element.In the absence of more restrictions, the element limited by sentence "including a ...", it is not excluded that There is also other identical elements in process, method, article or equipment including the element.

Each embodiment in this specification is all made of relevant mode and describes, same and similar portion between each embodiment Dividing may refer to each other, and each embodiment focuses on the differences from other embodiments.Especially for video camera For embodiment, since it is substantially similar to video signal output circuit embodiment, so being described relatively simple, related place Illustrate referring to the part of embodiment of the method.

The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the scope of the present invention.It is all Any modification, equivalent replacement, improvement and so within the spirit and principles in the present invention, are all contained in protection scope of the present invention It is interior.