CN101237565A

CN101237565A - Built-in driveway deviation alarming system

Info

Publication number: CN101237565A
Application number: CNA2007101333219A
Authority: CN
Inventors: 张为公; 于兵; 李旭; 蔡英凤
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2007-09-28
Filing date: 2007-09-28
Publication date: 2008-08-06

Abstract

An embedded type driveway deviation alarm system is used to carry out realtime monitoring of automobile driving safety on an expressway, wherein the analog video signal of a tracked driveway is collected through a vehicle camera; the analog video signal is decoded to generate digital signal code stream and is sent to the video interface of a high-speed medium processor DSP after buffering; then, a video processing module carries out processing of digital video signal; finally, processed video signal is sent to a coding chip to be output. The alarm system is provided with an analog/digital conversion and decoding circuit module, a buffering circuit module, a medium processor DSP circuit module and a coding and digital/analog conversion circuit module, wherein analog-video signal generates digital parallel code stream signal through an analog/digital conversion and decoding circuit; the digital parallel code stream signal, which is processed by a buffering circuit, is then sent to a medium processor DSP to complete driveway characteristic value extraction and finally, is sent to a coding and digital/analog conversion circuit after adjustment to realize output display.

Description

Built-in driveway deviation alarming system

Technical field

The present invention relates to the monitoring of vehicle on highway safety traffic, the particularly a kind of Real time identification highway institute's track of advancing left and right markings of getting on the car that are used for, to determine automobile and track relativeness, whether run-off-road travels monitors in real time to automobile, avoids taking place because of deviation the built-in driveway deviation alarming system of traffic accident.

Background technology

The purpose that deviation is reported to the police is to keep driver's straight-line travelling, sends warning to avoid traffic accident when the drowsy run-off-road of driver.The deviation warning device can be reminded the driver when high vehicle speeds, automobile is departing from the track of cruising, allows the driver in time correct traffic route.This is behind safety belt, safe steam pocket, another the safety device of installing in automobile.

According to the data that French Valeo SA company provides, there was traffic accident to cause in 2002 owing to deviation or change lane above 410,000.According to another adding up in annual nearly 1,500,000 traffic accidents of the U.S. owing to unconscious deviation causes.At home, because the traffic accident that deviation or change lane cause is just more,, caused many an innocent persons' people to lose life because domestic too many traffic accident is because lorry, passenger vehicle driver's super fatigue driving causes.

Current, driveway deviation alarming system mainly contains following several implementation: Vision Builder for Automated Inspection, the system based on the magnetic pilot signal, laser system and ITS infrastructure system.Their main distinction is the difference of perceptive mode: Vision Builder for Automated Inspection adopts computer vision technique identification lane line, and then can determine the relative position of automobile and traveling lane; Belong to the category of ITS safety system based on the system of magnetic pilot signal, it utilizes the magnetic strength on the car to know that transducer obtains the positional information between track and vehicle by burying the magnetic signal emitter underground on surface, highway track; Laser system then detects lane position by laser aid emitted laser bundle, and the lateral attitude of vehicle is estimated; ITS infrastructure belongs to the hardware category of ITS traffic safety system, such as speed alarm signal board is set near bend.Compare with alternate manner, machine vision has many advantages such as detection range is wide, information capacity is big, with low cost, become the main flow of present research and development, typical case's representative is as the SafeTRAC of the AutoVue of Iteris company, AssitWare company, the LDW of Infiniti etc., and they all adopt the markings and the conduct in the current track of advancing of vision technique identification automobile to realize the basis that deviation is reported to the police.But consider that for commerce these companies are as the externally open key technology wherein of secret abroad, and the domestic basic research stage that this still is in exploration is not also developed similar products.Wherein the deviation warning device of main flow is to be integrated in the microsystem by the form of pci bus with plug-in card mostly, and data exchange by the interface of being with on pci bus or the card and transmit, thereby finishes the various processing of image.This mode weak point is that volume is bigger, uses not to be very flexible.And present driveway deviation alarming system is collection, encoding and decoding and the storage of finishing image mostly, can not effectively detect early warning.

Summary of the invention

The object of the invention is to solve the problem that prior art exists, make full use of digital signal processor (DSP) characteristics such as operand is big, data transmission rate height that are content with very little in the image processing, a kind of built-in driveway deviation alarming system is provided, and can constantly upgrade to properties of product, the needs of aspects such as real time image collection, coding, decoding are satisfied in overlapping development.

The object of the invention is achieved through the following technical solutions:

A kind of built-in driveway deviation alarming system, it is characterized in that: the analog video signal of gathering tracked lane line by the vehicle-mounted pick-up head, after generating digital signal code stream buffering, decoding delivers to the video interface of high speed media processor DSP, and then by video processing module digital video signal is handled, at last the processed video signal is sent coding chip output.Being provided with mould/number transforms and decoding circuit module, buffer circuit module, Media Processor DSP circuit module, coding and D/A switch circuit module, analog video signal transforms through mould/number and decoding circuit generates the parallel signal bit stream of numeral, sending Media Processor DSP to carry out the track characteristic value after buffer circuit is handled must extract, after send coding and the output of D/A switch circuit to show after regulating.Mould/number transforms and the decoding circuit module adopts ADV7180; The buffer circuit module adopts the SN74CBT3245 chip; DSP adopts DM642 multimedia digital signal processor; Coding and D/A switch circuit module adopt ADV7170.

Compared with prior art, the present invention has following advantage:

1. this system can realize the almost repertoire of IMAQ and image processing on a slice Media Processor DM642, and it is the single-chip hardware platform of a multimedia embedded system that its abundant peripheral interface makes it be close to;

2. its complete programmability, can make the various multimedia signal dispose standards that it can compatible develop again, constitute general software platform, the system that makes upgrade in the future conveniently the change of hardware " need not just can increase systemic-function quickly and easily " by the update software code;

3. the collection vision signal that built-in driveway deviation alarming system can be real-time is in dynamic and static environment, especially can both obtain good image effect in the vehicle environment;

Description of drawings

Fig. 1 is the principle schematic of built-in driveway deviation alarming system;

Fig. 2 is a video decoding chip ADV7180 external circuit connection layout;

Fig. 3 is a video coding chip ADV7170 external circuit connection layout;

Fig. 4 is the outside connecting circuit figure of buffer chip SN74CBT3245;

Fig. 5 is Media Processor DM642 video input connecting circuit figure;

Fig. 6 is fpga chip XC2S3300E video output connecting circuit figure.

Embodiment

As Fig. 1, native system baseband signal flow process is as follows: be erected at the analog video signal image that camera CCD on the vehicle body takes tracked lane line, generate the parallel signal bit stream of numeral by Video Decoder 2 (ADV7180), because of the processing speed of peripheral circuit and DSP differs very big, so signal flow is wanted to cushion through SN74CBT3245 chip (Fig. 4) earlier, send Media Processor DM642 (its interface such as Fig. 5) then, digital signal enters the laggard runway characteristic value of DM642 and must extract, judge the relative position of vehicle body from lane line, information such as speed, after every two field picture processing, the characteristic value that extracts is delivered to video encoder 3 (ADV7170) after fpga chip XC2S3300E circuit (Fig. 6) is regulated, show through sending high definition TV after the format conversion.

As Fig. 2, video acquisition is used the video decoding chip ADV7180 of ADI company 40 pins, it is the Video Decoder of a multichannel input, supports various video signal format as Phase Alternation Line system, TSC-system, Sequential Color and Memory system etc.ADV7180 detects and finishes conversion automatically for the vision signal of input, and video decoding chip ADV7180 can provide the high-performance of catching various standard-definition signals.It adopts 40 little pin 6x6 LQFP or 5x5 LFCSP encapsulation, and integrated therein anti-sawtooth filter and ADLLT (Adaptive Digital Line length tracking, adaptive digital row length is followed the trail of).And support various video signal format as Phase Alternation Line system, TSC-system, Sequential Color and Memory system etc., can detect and finish conversion automatically for the vision signal of input, we select for use it as video coding chip based on above characteristic, can realize the seamless link with DSP.

The peripheral circuit connection description of chip is as follows: for guaranteeing the reliability of circuit, adopt two decoding chips, will send 0,1 port of high speed media processor DSP after vision signal mould/number conversion respectively.Because of circuit part identical, so one road signal is done connection description at this.23,29,30 of ADV7180 can connect multi-channel video signal, will connect 23 pins of ADV7180 from the camera signals of J18 terminal input among the design after above-mentioned filtering; The digital video signal P0-P7 correspondence of changing out the 18-11 pin that

17,16,10-5 meet 8 highway width switch chip SN74CBT3245, by corresponding AC8, AD8, AC7, AD7, AE7, AC6, AD6, AE6, AF6, the AF5 that meets DM642 of its 2-9 pin output; The 39 pin horizontal-drive signal HS of ADV7180 connect send U19-SN74CBT3245 behind the resistance in 33 Europe 13 pin buffering back from the output of 7 pin, 4 pin of the resistance RR34 that runs in are come out finally to send the AF4 pin of DM642 again by 3 pin; The VS/FIELD signal of ADV7180 connects 11 pin that connect U19 behind the resistance in 33 Europe, connects the AE5 pin that send DM642 behind the 33 Europe resistance by the output of 9 pin again; 38 pin of DM642/INTRQ signal connects the AF4 pin that 4 pin that 13 pin that connect U19 behind the 33 Europe resistance meet RR34 through the output of 7 pin again send DM642; The 11 pin LLC signals of ADV71 80 connect 11 pin that connect U19 behind the 33 Europe resistance; The 19 pin ELPF signals of DM642 connect 10nf electric capacity and simultaneously are connected 1.8v voltage again and after connecting 1.69 kilo-ohms of circuit with the 82nf capacitance series;

ADV7180DE

33,34 pin SCLK and SDA signal connect E4, the D3 pin of DM642; 32 pins of ADV7180 connect 3.3v voltage by 4 kilo-ohms resistance, use a single-point button control address (to press when button and to make 32 pin ground connection I at this moment simultaneously ²The C address is 42h, otherwise is 40h); The circuit that connects the crystal oscillator of 28.63636MHz and 1 megaohm resistance between 12,13 pins of ADV7180 and connect, 12,13 pin are used the capacity earth of a 47pf respectively simultaneously; The electric capacity of serial connection 0.1uf, the capacity earth of each personal 0.1uf simultaneously between 25,26 pins of ADV7180; 31 pin of ADV7180/RESET signal connects the reset signal P4 pin of DM642; 1,4 pins of ADV7180 connect 3.3v voltage, and 36,14 connect the 1.8v digital voltage, and 27 pin connect the 1.8v analog voltage signal, and 20 pin connect 1.8vPLL voltage, the equal ground connection of 40,3,15,35,28,21,24,22 pins.

As Fig. 3,7170 chips of ADI company are adopted in video output, and it supports to comprise Y, U, C; NTSCM; PALB/D/G/H/I is in interior various video form output, and the digital video signal that comes out from fpga chip XC2S3300E is transformed into analog signal through 7170, send TV to show by the output of J1 terminal again.The P0-P7 signal of the 38-42 of ADV7170,2-4 pin correspondence meets C8, D8, A9, B9, C9, D9, A10, the B10 of DM642; ADV7170DE27,26 pins meet 7,6 of J1; The SCLOCK of 23, the 24 pin correspondences of ADV7170, SDATA signal connect SCLK, SDA network after connecing 100 Europe resistance; 7170 10,19,21,29,43 pins connect simulation ground; 7170 44 pins connect the 27M crystal oscillator; 7170 1,11,20,28,30 pins connect 3.3v voltage.

Video coding chip ADV7170 is a kind of high-quality, monolithic, multi-format Video Decoder and figure digital quantizer, this multi-format decoder is supported the standard handovers of PAL, NTSC and SECAM, can be a kind of digitized ITU-R BT.656 form with above synthesized form and S-video formal transformation.ADV7170 also supports the vision signal of RGB/YPrPb combination is decoded as single YPrPb or RGB digital pixel output stream.ADV7401 also supports image digitazation; It can convert the digitlization of RGB figure signal to the SXGA ratio from VGA, and converts them to digital rgb or YPrPb digital pixel output stream.Because ADV7170 has the ability to handle CVBS and single-definition rgb signal simultaneously, means that it has the function of SCART and covering, can control these mixed signals by empty pin fast.

As Fig. 4, be the outside connecting circuit figure of buffer chip SN74CBT3245.The analog video signal image generates the parallel signal bit stream of numeral by Video Decoder 2 (ADV7180), because of the processing speed of peripheral circuit and DSP differs very big, so signal flow wants elder generation to cushion through the SN74CBT3245 chip, send Media Processor DM642 then.

As Fig. 5, DM642 is that TI company is specially at a multimedia digital signal processor of digital video and voice applications exploitation.It is based on the high performance VelociTI VL of second generation IW (Very Long In2structionWords) structure, and 32 of single instrction word lengths can 8 instructions of while parallel processing.Under main clock frequency 600 MHz, it can reach the peak value computational speed of 4 800M IPS, and having 64 32 general registers and 6 ALUs and 2 multipliers, its multiplication unit can be carried out 2 16 * 16 multiplication or 48 * 8 multiplication in each clock cycle.Powerful operation capacity makes DM642 can be used as the core processor that real-time video is handled fully like this.

As Fig. 6, native system employing fpga chip XC2S3300E realization Media Processor DM642 video channel is connected with the ADV7170 video encoder, finish the advanced video overlap-add procedure, existing in fact three kinds of operations: the one, the 8bit video data of exporting from the DM642 video channel is directly connected to the ADV7170 video encoder; The 2nd, the 16bit data conversion that DM642 is exported becomes the 8bit data to send ADV7170 video encoder; The 3rd, the stacked data that inputs to FPGA from DM642 is added that special view data exports the ADV7170 video encoder to.Fpga chip XC2S300E can send to realize Premium Features (as OSD) by FPGA, and this port directly is connected to the ADV7180 video encoder by video under the acquiescence mode.This encoder can carry out the coding of RGB, HD synthetic video and NTSC, PAL composite video, also can the S-Video that rely on the ADV7180 internal register to programme be encoded.The inside programming register of ADV7180 is configured by the I2C bus of DM642.

Claims

1, a kind of built-in driveway deviation alarming system, it is characterized in that: the analog video signal of gathering tracked lane line by the vehicle-mounted pick-up head, after generating digital signal code stream buffering, decoding delivers to the video interface of high speed media processor DSP, processor DSP carries out algorithm process to the input data, send FPGA via video output, realistic as required existing video superimpose is handled, and at last the processed video signal is sent coding chip output.

2, built-in driveway deviation alarming system according to claim 1, it is characterized in that: be provided with mould/number and transform and decoding circuit module, buffer circuit module, Media Processor DSP circuit module, coding and D/A switch circuit module, analog video signal transforms through mould/number and decoding circuit generates the parallel signal bit stream of numeral, sending Media Processor DSP to carry out the track characteristic value after buffer circuit is handled must extract, after send coding and the output of D/A switch circuit to show after regulating.

3, built-in driveway deviation alarming system according to claim 2 is characterized in that: mould/number transforms and the decoding circuit module adopts ADV7180; The buffer circuit module adopts the SN74CBT3245 chip; DSP adopts DM642 multimedia digital signal processor; Coding and D/A switch circuit module adopt ADV7170.