The multi-mode camera image processing circuit
Technical field
The utility model discloses a kind of image processing circuit, particularly a kind of multi-mode camera image processing circuit.
Background technology
Along with improving constantly of people's living standard, people's security protection consciousness is also more and more stronger, and video camera is as the important devices of safety-security area, and is not strange in people's life.Along with the manufacturing technology of image sensing device is brought in constant renewal in development, CCD (being charge coupled device) is with its high sensitivity, the color reducibility of high-quality, superpower photosensitive effect, become traditional IMAQ core devices, and the COMS of rising in recent years (complementary mos device) becomes the transition substitute products of CCD gradually with its high pixel, low-power consumption, small size, easy of integration, low price or the like advantage always.The simultaneous camera image processing techniques is also more and more paid close attention to by people, though advance by leaps and bounds before the technical development now, but video camera still has weak point under some particular application, remain to be improved, such as these several respects such as color rendition authenticity, signal to noise ratio, night vision photography quality all be have to be hoisted.In the prior art, the principle that video camera can obtain image is, by a kind of optical lens the light of object reflection is accurately rendered on the target surface (photosurface) of imageing sensor in the video camera, on behalf of the light signal of object, imageing sensor will be converted to the signal of telecommunication by internal circuit again, through post processing electric circuit, show in the display terminal reduction at last.In the physics, defined only a kind of electromagnetic wave.The light that people's eyes can be seen is a kind of " visible light ", wave-length coverage approximately is that 400 nanometers are to 700 nanometers, and also depositing simultaneously the light of a kind of crying " infrared light " in the light wave, wave-length coverage approximately is that 700 nanometers are between 2500 nanometers, infrared light is the light source that a kind of naked eyes can't be seen, but video camera can be sensed visible light and infrared light simultaneously, the night vision camera machine technology has just appearred thus, daytime, video camera can come capturing video by visible light, and video camera just utilizes infrared light to come capturing video under night.
Traditional video camera only has the simple function of shooting on daytime or shooting at night, can not satisfy people's demand already, so double mode video camera just arises at the historic moment, at present, the implementation method of double mode video camera is varied, please be: CN201118758Y referring to notification number, the patent No. is: 200720100216 patent, it has installed infrared generator additional on video camera, send the sightless infrared ray of human eye at night by infrared generator, after guarded region carried out the light reinforcement, utilize video camera that guarded region is monitored again, still, it still exists the bright inadequately shortcoming of night monitoring image; Please be again: CN2472429Y referring to notification number, the patent No. is: 01235487 and notification number be: the CN201274542Y/ patent No. is: 200820137493 patent, in two patents all record be behind camera lens, to be provided with filter, utilize daytime filter with the infrared light filtering, directly infrared light is gathered the technology of shooting evening, though in theory, this technical scheme is feasible, but, in the limited space of video camera, add one or two filter, will certainly increase the volume of video camera self, and, also the structure of ambassador's video camera becomes complicated, in addition during the switching of filter by Mechanical Driven, its handoff procedure is difficult to guarantee, exists hidden danger of quality.Moreover, at present, no matter be the video camera of which kind of form, can realize daytime, double mode shooting at night at most, and such as: under the situations such as greasy weather, cloudy day, grey haze weather, or the shooting occasion etc. of utilizing high light to suppress to obtain car plate at night all seems powerless.Therefore, how with advanced image sensing technology, created better image effect, make the video camera product be applied to the field of more wide model, under environments for use such as monitoring, vehicle-mounted, medicine equipment, Industry Control, low-light shooting, all show superior performance, just become a new developing direction in monitoring camera field.
Summary of the invention
When taking night at the above-mentioned video camera of mentioning of the prior art, image is clear inadequately, bright, and the shortcoming that only has double mode work, the utility model provides a kind of new camera review treatment circuit, it utilizes imageing sensor can respond to visible light, can respond to ultrared principle again, different images effect under the different light intensity of DSP unit is adjusted program to be stored in respectively in the different memory cell, gather extraneous visible light by the visible light collecting unit, and make DSP connect different memory cell according to visible light intensity, promptly call different image effects and adjust program, the picture signal that imageing sensor collects is carried out different processing, make no matter still be night, perhaps other clouds and mists by day, all can obtain clear more bright image under the weather such as ash haze.
The technical scheme that its technical problem that solves the utility model adopts is: a kind of multi-mode camera image processing circuit, comprise the DSP unit, image sensor cell, CDS/AGC graphics processing unit and output unit, the image sensor cell acquired signal is after the sampling of CDS/AGC graphics processing unit is amplified, input to DSP, after the DSP processing, export by output unit, also include the visible light collecting unit in the circuit, control unit and store the memory cell that the different images effect is adjusted program more than two, the signal output part output visible light signal of visible light collecting unit is given control unit, the memory cell that control unit control is connected with DSP.
The technical scheme that its technical problem that solves the utility model adopts further comprises:
Described visible light collecting unit adopts photo resistance.
Described control unit adopts MCU or electronic control switch.
Described memory cell adopts EEPROM.
The beneficial effects of the utility model are: double mode camera review treatment technology of the present utility model, exactly in order to improve video camera by day under the bright light environments and the picture quality that evening, dark surrounds was obtained down, particularly in protection and monitor field, adopted the video camera of double mode image processing techniques, no matter by day or all can obtain clear more bright image under night.Adopted video camera of the present utility model to compare with traditional video camera, on image device definition, color, signal to noise ratio, night vision effect, all had significantly and promoted, the product power consumption is little, stable performance, particularly on the night vision effect, water proof type night vision camera machine of the present utility model changes dark red outer machine relatively with the coloured silk that uses on the market, under the equal illumination environment, the image quality of our company's product all is better than only having used several times of infrared machine of the black function of color commentaries on classics, and the product imaging of our company is brighter more clear.Adopt multi-mode camera image processing techniques of the present utility model to make the application of video camera more extensive, not only can obtain good image by day, in night, also can guarantee the preferable image effect, in charge station, utilize night high light to suppress to obtain in the shooting occasion of sharp image of car plate, more be to use handyly, multimodal image processing techniques is brought into play especially incisively and vividly.
Below in conjunction with the drawings and specific embodiments the utility model is described further.
Description of drawings
Fig. 1 is the utility model embodiment one circuit block diagram.
Fig. 2 is the utility model embodiment two circuit block diagrams.
Fig. 3 is the utility model circuit theory diagrams.
Embodiment
Present embodiment is the utility model preferred implementation, and other all its principles are identical with present embodiment or approximate with basic structure, all within the utility model protection range.
Embodiment one, please referring to accompanying drawing 1, circuit mainly comprises a DSP unit in the present embodiment, an image sensor cell, a CDS/AGC graphics processing unit and a video output unit, DSP (being digital signal processor) chip has powerful software function and superior hardware performance, used the treatment circuit of DSP, not only simplified the hardware complexity of product greatly, by the programming of software flexibly, can also realize a lot of product characteristics functions, so, after DSP occurs, nearly all video processing circuits has all adopted the Digital Signal Processing mode, that adopt in the present embodiment is the professional DSP that is specifically designed to the shooting treatment circuit, utilizes DSP to carry out Video processing.Image sensor cell adopts CCD (being charge coupled device) or COMS (complementary mos device), converts picture signal to the signal of telecommunication by image sensor cell.Because the output waveform of each pixel of ccd sensor is picture signal in portion of time only, in all the other times reset level and interference, in order to take out picture signal and to eliminate and disturb, adopt sample-and-hold circuit, after each picture element signal is sampled, by an electric capacity signal is kept getting off, up to the next picture element signal of sampling, in the present embodiment, to the maintenance of taking a sample of the output waveform of ccd sensor, adopt the CDS unit, be correlating double sampling circuit (Correlated Double Sampling), need carry out the signal processing and amplifying through the picture signal of taking a sample after keeping in the CDS unit, be AGC, in the present embodiment, waveform sampling maintenance and signal processing and amplifying are lumped together, it is the CDS/AGC graphics processing unit, picture signal input DSP through after the processing of CDS/AGC graphics processing unit has DSP that the level of imageing sensor is provided, vertical driving signal, the electronic shutter control impuls, read reset pulse, also have the sampling of CDS circuit part to keep pulse, the clamped pulse of optical black level, the control signal of agc circuit part, in the present embodiment, DSP also realizes A/D conversion input function and D/A conversion output function.After picture signal is handled in DSP, export by video output unit.
Also comprise a MCU in the present embodiment, in the present embodiment, MCU can adopt 51 series monolithics, or other single-chip microcomputers, be connected with a visible light collecting unit on the data terminal of MCU, in the present embodiment, the visible light collecting unit adopts photo resistance, the visible light collecting unit outputs signal to MCU, and MCU can judge extraneous light intensity by the photo resistance resistance, is identified as cloudy day, daytime or night etc. by light intensity.Because the read-only storage that DSP inside does not carry so the software that writes is deposited in earlier in the external memory storage, is called in formula work again after each DSP power-on-reset.In the present embodiment, be connected with plural memory cell on the program input of DSP, in the present embodiment, memory cell adopts EEPROM, makes things convenient for program read-write and modification, when specifically implementing, also can adopt other to have the memory of memory function.Each memory cell is connected with the program input of DSP by MUX respectively, and MCU is connected with the MUX Enable Pin, the memory cell that control is connected with DSP.Perhaps, each memory cell directly is connected with the program input of DSP by MCU respectively.
Embodiment two, and please referring to accompanying drawing 2, identical among other parts of circuit and the embodiment one in the present embodiment, difference is.Comprise an electronic control switch in the present embodiment, the visible light collecting unit outputs signal to electronic control switch, and electronic control switch is connected with the MUX Enable Pin, the memory cell that control is connected with DSP.Perhaps, adopt MUX directly as electronic control switch, the visible light collecting unit directly is connected with the MUX Enable Pin, the memory cell that control is connected with DSP.
Followingly provide a kind of specific implementation circuit that the utility model is described further, please referring to accompanying drawing 3, in the present embodiment, the employing model is that the special-purpose extensive signal processor U6 of the CCD colour TV camera of CXD3142R is a dsp chip, adopting signal in the present embodiment is the ccd image sensor U5 induction video image of ICX405AK (or model is ICX633AK), dsp chip U6 output vertical driving signal is given CCD vertical driver U10, in the present embodiment, it is the CCD vertical driver of AA87222 that CCD vertical driver U10 adopts model, CCD vertical driver U10 input signal is given ccd image sensor U5, ccd image sensor U5 output image signal is given CCD video preamplifier U9, after amplifying, CCD video preamplifier U9 is transferred to dsp chip U6, in the present embodiment, it is the CCD video preamplifier of CXA3796 that CCD video preamplifier U9 adopts model.Dsp chip U6 outputting video signal is given low-power consumption video amplifier U3, and in the present embodiment, it is the low-power consumption video amplifier of SCA2575 (or IA171) that low-power consumption video amplifier U3 adopts model, does video output by low-power consumption video amplifier U3.Adopt the serial ports direct linkage type EEPROM of BR9020F4k model as memory cell in the present embodiment, be that example describes with two in the present embodiment, be respectively storage chip U4 and storage chip U7, in the present embodiment, store image effect adjustment on daytime program among the storage chip U4, store image effect adjustment at night program among the storage chip U7, the input/output terminal of storage chip U4 and storage chip U7 is connected with MUX U2 respectively, in the present embodiment, it is the MUX of CD4053 that MUX U2 adopts model, MUX U2 is connected with the program input of dsp chip U6, MUX U2 Enable Pin is connected with the low level drive circuit with the high level drive circuit respectively, the high level drive circuit is contact H-5V in the accompanying drawing 3, the low level drive circuit is contact H-L, the conversion of high-low level realizes control by external photo resistance, in the present embodiment, photo resistance directly can be connected between H-5V contact and the ground, contact H-L is connected in 9 of MUX U2,10, on 11 pins, as the switching signal of MUX U2.
The foregoing description adopts voltage detector U8 directly to control the control program of calling in dsp chip U6 as electronic control switch, and the foregoing description is applicable in the double mode video camera and uses.During concrete enforcement, MCU of input discerns after can converting the tissue of photo resistance to digital signal by analog to digital converter, concrete resistance by MCU identification, it is divided into a plurality of ranks, and export control signal respectively and control corresponding storage chip and call in control program and give dsp chip U6, thereby realize multi-mode camera.
The utility model in use, storage image effect on daytime is adjusted program in storage chip U4, at the day mode that daytime, image effect was adjusted, the main parameter of adjusting has: the electronic shutter automatic range is adjusted into, and between 1/50th seconds to 100,000/second, adjusts black position standard to 0.05 and lies prostrate between 0.1 volt, adjustment AGC is 6DB, the brightness of image is adjusted between 0.8 volt to 0.9 volt, closes colored inhibit feature, and it is normal to regulating automatically between 9600K that the white balance aspect is adjusted into 3600K; Storage image effect at night is adjusted program in storage chip U7, the pattern at night that the night vision image effect is adjusted, the main parameter of adjusting has: the electronic shutter automatic range is adjusted between 1/50th seconds to 50,000/second, black position standard is adjusted between 0.15 volt to 0.25 volt, the carrier chrominance signal Close All, the colour subcarrier Close All, AGC is adjusted into 22DB, brightness is adjusted between 0.85 volt to 1 volt, and the white balance aspect is adjusted between the 3200K-9600K and regulates normally automatically.Perhaps also be provided with other storage chips, be implemented in charge station, utilize night the high light inhibition to obtain the functions such as shooting of the sharp image of car plate, realize the multi-mode shooting.When photo resistance identification is judged as daytime, voltage detector U8 exports control signal, control MUX U2 is connected storage chip U4 with the program input of dsp chip U6, the image effect that dsp chip U6 calls in the storage chip U4 is adjusted program, video image to ccd image sensor U5 induction carries out corresponding parameter adjustment, and input; When photo resistance identification is judged as night, voltage detector U8 exports control signal, control MUX U2 is connected storage chip U7 with the program input of dsp chip U6, the image effect that dsp chip U6 calls in the storage chip U7 is adjusted program, video image to ccd image sensor U5 induction carries out corresponding parameter adjustment, and input, thereby realize double mode control.During concrete enforcement, also the photo resistance resistance can be divided into several grades, control corresponding storage chip by MCU respectively and call in program, realize multi-mode control.