CN201001169Y

CN201001169Y - Video collecting device for vehicle-mounted surrounding

Info

Publication number: CN201001169Y
Application number: CNU2007200338460U
Authority: CN
Inventors: 张为公; 秦文虎; 李旭; 于兵; 刘晔波
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2007-01-26
Filing date: 2007-01-26
Publication date: 2008-01-02
Anticipated expiration: 2017-01-26

Abstract

In order to solve the problems that the PCI interface is not firm, the development cycle is long, and the software and hardware cost are high in the prior art, the utility model provides a video gathering device applied to the on-board environment, which consists of a video signal mode/number switching circuit (1), a video format switching and PCI interface circuit (2), and a CPCI interface circuit (3), wherein a video signal is input into the video signal mode/number switching circuit (1), the video signal mode/number switching circuit (1) is connected with the video format switching and PCI interface circuit (2), the video format switching and PCI interface circuit (2), is connected with the CPCI interface circuit (3), and the CPCI interface circuit (3) is connected with a computer. The utility model reduces the cost, is convenient for software development, improves the electrical characteristic of the signal on the interface, and enhances the firmness of the interface.

Description

Be applied to the video acquisition device of vehicle environment

Technical field

The utility model relates to vehicle-mounted industrial computer, particularly is applied to the video acquisition device of vehicle environment.

Background technology

Video acquisition device is capture device again, can be with the video information digitlization and with digitized information storage or play back with it.The video data of the outputs such as vision signal that it can be exported analog video camera, video tape recorder, LD video disc player, television set or the blended data input of video/audio are handled, and convert the recognizable numerical data of computer to, be stored in the computer, but become the video data file of editing and processing.But now on the market this video acquisition device greatly part all be to adopt peripheral component interconnected bus interface (hereinafter to be referred as pci interface), be suitable for use in more stable, the ideal environment.More abominable at environment, especially aspect mobile unit, the video acquisition device of pci interface is often because the problem of pci interface itself causes the inefficacy or the physical damage of whole device, this mainly is insecure owing to pci interface, comes off easily under adverse circumstances, ruptures and cause.

The existing video acquisition device that can be used under the vehicle environment all is to adopt programming devices such as FPGA or CPLD to realize the work of pci interface and Video processing basically, the construction cycle of the exploitation of programming device pci interface is long, hardware and software cost is higher, is not suitable for the applied environment of low side.

Summary of the invention

The purpose of this utility model is to address the above problem, and a kind of video acquisition device that is applied to vehicle environment is provided, and it can reduce cost, and makes things convenient for software development, and improves the opering characteristic of electric apparatus of signal on interface, strengthens the fastness of interface.

The utility model adopts following technical scheme to solve technical problem:

A kind of video acquisition device that is applied to vehicle environment, by vision signal mould/number conversion circuit, video format conversion and peripheral component interconnected bus interface circuit (hereinafter to be referred as video format conversion and pci interface circuit) and compact periphery components interconnection interface circuit (hereinafter to be referred as the CPCI interface circuit) are formed, the vision signal input connects vision signal mould/number conversion circuit, the output of vision signal mould/number conversion circuit connects video format conversion and pci interface circuit, video format conversion and pci interface circuit connect the CPCI interface circuit, and CPCI interface circuit and computer join.

Compared with prior art, the utlity model has following advantage:

1, the collection vision signal that video acquisition device can be real-time, and can reappearing on PC is in dynamic and static environment, especially can both obtain good image effect in the vehicle environment.

2, adopt the CPCI interface to be connected, improved the electrical characteristic of video-unit signal and the reliability of whole device, make it under condition of severe, especially work that can be reliable and secure under vehicle-mounted condition with processor.

3, cost reduction, software development are conveniently.

Description of drawings

Fig. 1 is the schematic block circuit diagram of video acquisition device of the present utility model.

Fig. 2 is the signal connection layout of SAA7111A.

Fig. 3 is the signal connection layout of SAA7146A.

Fig. 4 is the signal connection layout of CPCI interface.

Embodiment

A kind of video acquisition device (with reference to Fig. 1) that is applied to vehicle environment, form by vision signal mould/number conversion circuit 1, video format conversion and pci interface circuit 2 and CPCI interface circuit 3, the vision signal input connects vision signal mould/number conversion circuit 1, vision signal mould/number conversion circuit 1 connects video format conversion and pci interface circuit 2, video format conversion and pci interface circuit 2 connect CPCI interface circuit 3, and CPCI interface circuit 3 joins with computer.

Above-mentioned vision signal mould/number conversion circuit 1 adopts the SAA7111A chip of Philips company, above-mentioned video format conversion and peripheral component interconnected bus interface circuit 2 adopt the SAA7146A chip of Philips company, 43 of SAA7111A, 42,39～No. 34 pin is connected respectively to 1～4 of SAA7146A, 7～No. 10 pin, the field sync signal VS of No. 30 pin of SAA7111A, the clock reference output signal CREF of the clock signal LLC of No. 20 pin and No. 22 pin is connected respectively to 11 of SAA7146A, 13, No. 14 pin, the capable synchronous reference signal HREF of No. 31 pin of SAA7111A is connected to No. 12 pin of SAA7146A, No. 62 pin of SAA7111A, I2C bus interface (the SCL of No. 63 pin, SDA) be connected respectively to the 136th of SAA7146A, No. 137 pin, and 136 of SAA7146A, No. 137 pin are respectively by pull-up resistor R10, R9 links to each other with power supply, and the PCI agreement end signal of SAA7146A directly is connected with above-mentioned compact periphery components interconnecting bus interface circuit 3 corresponding signals.

Vision signal mould/number conversion circuit 1 mainly comprises filter circuit and A/D conversion chip.The A/D conversion chip is selected the SAA7111A of Philips company, SAA7111A is a kind of video input processor (VIP), field sync signal VREF in the SAA7111A chip, row synchronous reference signal HREF, parity field signal RESI, pixel clock signal LLC2 are directly drawn by pin, thereby saved the design of clock synchronization circuit in the past, its reliability also increases, the integrated reliability that makes of internal system PHASE-LOCKED LOOP PLL TECHNIQUE is greatly improved, and greatly reduces design complexities.The parameter that needs in the IMAQs such as its mode of operation, input port selection, color control to control all has its internal register decision.Ppu can be read and write control to all registers by the I2C bus.

Video format conversion and pci interface circuit 2 adopt the SAA7146A chip of Philips company.SAA7146A can support full bandwidth PCI master to read and lead and write, and major and minor pattern satisfies PCI local bus specification 2.1, and transfer of data can reach 132Mbyte/s.Because SAA7146A has and the video interface of SAA7111A compatibility and inter-process circuit efficiently, can not adopt memory, only need that decoder chip and interface chip are carried out seamless link simply and just can realize real time video signals and high speed acquisition and processing, simplify the design of system greatly, shortened the construction cycle.The I2C interface of SAA7146A can programme to SAA7111A and control easily.When writing driving, directly SAA7146A is operated just passable like this.And the cost of the chipset of SAA7111A and SAA7146A is lower, but can obtain good video effect.And realize Video processing with programming device, and if oneself develop pci interface, difficulty is big and the construction cycle is longer, if buy the pci interface program, expense is higher, and is inadvisable.So this programme has good cost performance.

CPCI interface circuit 3 (with reference to Fig. 4) is according to the regulation of CPCI specification protocol, and all holding wires of CPCI are connected with video format conversion and pci interface circuit 2.CPCI is more robust PCI version, and higher data transmission bauds is provided.

Specific implementation process is as follows: selected translative mode in SAA7111A, format transformation is selected Y for use: U: V=4: 2: 2 pattern, VPO8～the VPO15 of chip is as the transmission channel of data, consider that the video under the Windows environment shows, the form of transmission adopts the standard of CCIR656, promptly according to 4 bytes of sequence delivery of U-Y V-Y, SAA7111A and SAA7146A are carried out seamless link, VPO8～VPO15 of SAA7111A is directly connected to the D1A mouth of SAA7146A as data wire, the field sync signal VS that while is produced by SAA711A1, row synchronous reference signal HREF, clock signal LLC and clock reference output CREF, SAA7111A and SAA7146A can carry out seamless link, these signals can directly be received SAA7146A and get on, owing to adopted the output format of CCIR656, the CREF signal can directly connect the PXQ_A of SAA7146A, LLC receives LLC_A, VS receives VS_A, HREF is as the input of HS_A signal, the holding wire SDA (data wire) and the SCL (clock line) of the I2C bus of SAA7146A are directly connected on the bus signal line of SAA7111A simultaneously, the internal register of read-write SAA7111A must add in these two buses simultaneously and draw resistance.And the signal of the PCI of SAA7146A end directly directly connects with the signal of CPCI interface.

Claims

1, a kind of video acquisition device that is applied to vehicle environment is characterized in that,

By vision signal mould/number conversion circuit (1), video format conversion and peripheral component interconnected bus interface circuit (2) and compact periphery components interconnection interface circuit (3) are formed, the vision signal input connects vision signal mould/number conversion circuit (1), the output of vision signal mould/number conversion circuit (1) connects video format conversion and peripheral component interconnected bus interface circuit (2), video format conversion and peripheral component interconnected bus interface circuit (2) connect compact periphery components interconnecting bus interface circuit (3), and compact periphery components interconnecting bus interface circuit (3) joins with computer.

2, the video acquisition device that is applied to vehicle environment according to claim 1 is characterized in that,

Above-mentioned vision signal mould/number conversion circuit (1) adopts the SAA7111A chip of Philips company, above-mentioned video format conversion and peripheral component interconnected bus interface circuit (2) adopt the SAA7146A chip of Philips company, 43 of SAA7111A, 42,39～No. 34 pin is connected respectively to 1～4 of SAA7146A, 7～No. 10 pin, the field sync signal (VS) of No. 30 pin of SAA7111A, the clock signal (LLC) of No. 20 pin and the clock reference output signal (CREF) of No. 22 pin are connected respectively to 11 of SAA7146A, 13, No. 14 pin, the capable synchronous reference signal (HREF) of No. 31 pin of SAA7111A is connected to No. 12 pin of SAA7146A, No. 62 pin of SAA7111A, I2C bus interface (the SCL of No. 63 pin, SDA) be connected respectively to the 136th of SAA7146A, No. 137 pin, and 136 of SAA7146A, No. 137 pin are respectively by pull-up resistor (R10, R9) link to each other with power supply, the PCI agreement end signal of SAA7146A directly is connected with the corresponding signal of above-mentioned compact periphery components interconnecting bus interface circuit (3).