CN101282463A - Monitoring system for capturing remote wireless image based on DCT field differential value transmission - Google Patents

Abstract

The invention is a remote wireless image monitoring system based on DCT domain differential transmission, including a spot image capturing module, a wireless data transmitting module, a data central server software and a remote monitoring terminal software. The spot monitoring terminal detects the image and triggers alarm and transmits the captured image only when the image changes; DCT domain differential image transmission mode is employed during transmitting process. The remote wireless image monitoring system based on DCT domain differential transmission of the invention has advantages that the solution greatly reduces flux of network transmission, thereby remarkably reduces charge of monitored data flux, meanwhile greatly reduces system consumption; modular design and universal industrial standard are employed, which provides a compact system with very low consumption, excellent expandability and strong practicability.

Description

Monitoring system for capturing remote wireless image based on the transmission of DCT territory difference

Technical field

The present invention relates to the monitoring technique field, particularly a kind of monitoring system for capturing remote wireless image based on the transmission of DCT territory difference.

Background technology

The production and the life of safety impel people to grow with each passing day to the demand of production equipment fail safe with to the serious hope that makes up intelligent family.The means of wireless data transmission and method are more and more now, but all can't overcome the lower defective of transmission rate, and transmission cost is higher.

In addition on the one hand, reality has proposed the requirement of energy-saving and emission-reduction to all trades and professions, and adopt the modular compact design, extensive welcome that monitoring product with low-power consumption will inevitably be subjected to society.

The shortcoming of traditional images supervisory control system is with not enough: wired analog video transmission means is adopted in traditional monitoring, to monitoring on-the-spot wiring more complicated, and equipment is expensive heavy, the maintenance cost height, install and lack flexibility, need to be equipped with lot of manpower and material resources simultaneously, cost is higher, efficient is lower.

And computer network, wireless communication technology and development of digital image in recent years also make me select a kind of wireless data transmission technology of with low cost, novel practical, and building a kind of efficient, real-time image collection supervisory control system becomes possibility.

For consideration to above-mentioned reason, a new generation supervisory control system arise at the historic moment, with brand-new Digital image technology treatment technology be applied to numerous people production and the life in be the emphasis of system design.In numerous production places, need emphasis to consider the extraction and analysis requirement of individual picture, and in order to control application cost, what the camera that the IMAQ supervisory control system provides adopted focus, and save The Cloud Terrace, so can only monitor fixing target in a fixed manner.In addition, the supervisory control system of a new generation has adopted very ripe network (the GRPS net of China Mobile or the CDMA net of CHINAUNICOM) of mobile communication carrier's technology and maximum at present the Internet to carry out image data transmission, guaranteed the reliability of system, also make monitoring range and transmission range that qualitative leap has been arranged, system can monitor the zone that any signal can cover, by Internet user's checking monitoring image whenever and wherever possible, so this system can be widely used in family's security protection, the intelligent residential district, traffic, bank, public security, electric power, various production monitorings, contamination monitoring, fields such as geological disaster hidden danger point monitoring, or some difficult wiring, wiring cost height and the place that need monitor.But this system provides a kind of supervisory control system solution of fast and flexible change monitoring scheme cost cheapness undoubtedly for the demand.

Some like products of Chu Xianing all possess above-mentioned functions basically in the market, but the system that exists usually is huge, complicated, data volume is big, power consumption is high, expensive problem.

Summary of the invention

Powerful by the purpose of this invention is to provide, practical, economical and small and exquisite supervisory control system realizes low data bulk, the requirement of low-power consumption.

The technical scheme that the present invention deals with problems is as follows.

Remote wireless image supervisory control system based on the transmission of DCT territory difference of the present invention comprises image scene acquisition module, wireless data transfer module, data center server software and remote monitoring terminal software.IMAQ compression module and wireless data transfer module are formed the on-site supervision end, finish the collection compression, encryption of image scene data etc.; Data center server and remote monitoring end are formed client, and data center server operation service end software is wherein finished management, the data of on-site supervision node, the functions such as forwarding of order; Remote client's monitoring client software of the corresponding exploitation of remote monitoring end PC operation is finished functions such as logon data central server, picture control, order transmission;

On-site supervision end detected image is and if only if image when changing, and the on-site supervision end just triggers reports to the police and the image that collects is transmitted; In transmission course, adopt DCT territory error image transmission means, its step is,

Steps A: give remote monitoring terminal software the image complete transmission that one width of cloth collects;

Step B: vicissitudinous part between a transmission and the last sub-picture;

Step C: obtain the difference between two width of cloth images;

Step D: will and only this difference be transmitted;

Step e: remote monitoring terminal software receives this difference and carries out image and recover;

Step F: behind the certain hour, be transferred to remote monitoring terminal software one secondary complete image more at interval;

Repeating step A is to step F.

The step whether detected image changes is:

(1) with last width of cloth picture decoding to the DCT territory, obtain corresponding brightness and color DCT numeric field data;

(2) calculate all 8 * 8 luminance texture and color characteristics, preserve corresponding characteristic value;

(3) the back piece image is decoded to the DCT territory, obtains corresponding brightness and color DCT numeric field data, and calculate all 8 * 8 characteristic of correspondence values;

(4) luminance texture and the color feature value to all corresponding pieces of image of front and back two width of cloth compares, and the position and the quantity of record different masses;

(5) whether the position of the piece that changes of judging characteristic value concentrates on corresponding zone, determines whether the back piece image occurs changing.

The step of obtaining the difference between two width of cloth images is:

(1) calculates the variation difference that obtains the DCT territory;

(2) this difference is carried out corresponding quantization, coding, add necessary information and be packaged into image code stream;

(3) decoding end is carried out corresponding contrary the processing.

The invention has the beneficial effects as follows: the scheme that the present invention adopts can significantly reduce the flow of Network Transmission, thereby reduces the data traffic expense of monitoring significantly, also greatly reduces system power dissipation simultaneously; Adopt modularized design, adopt global industrywide standard, system's compact, power consumption are extremely low, and are with good expansibility, and be practical.

Description of drawings

Fig. 1 is a remote wireless image supervisory control system overall construction drawing.

Fig. 2 is a wireless monitoring terminal basic structure block diagram.

Fig. 3 is an Image Change Detection realization flow block diagram.

Fig. 4 extracts coding realization flow block diagram for image difference.

Embodiment

As shown in Figure 1, form by three parts based on the radio image collecting supervisory control system of DCT territory difference transmission: 1, image scene acquisition module; 2, wireless data transfer module; 3, data center server software and remote monitoring terminal software.Wherein IMAQ compression module and wireless data transfer module are formed the on-site supervision end, finish the collection compression, encryption of image scene data etc.The on-site supervision acquisition terminal can be by the ARM embedded microcontroller, popular now embedded real time system, and for example operating systems such as the μ C/OS-II of maturation and function admirable, built-in Linux constitute; Client is made up of data center server and remote monitoring end, and the service end software of the special exploitation of data center server operation is wherein finished management, the data of on-site supervision node, the functions such as forwarding of order; Remote client's monitoring client software of the corresponding exploitation of remote monitoring end PC operation, this software has succinct interface easy to operate, finishes functions such as logon data central server, picture control, order transmission.Adopt this pattern, major advantage is the data center server that only needs a fixed ip address, and the client all can realize functions such as monitoring in the place that any energy chain meets Internet.This radio image collecting supervisory control system is simple in structure, and extensibility is strong.

The IMAQ compression module: monitor terminal image capture module, its function are to catch instantaneous vision signal from common camera, are compressed into the jpeg format image through picture processing chip.This module is finished the extraction of DCT territory difference simultaneously, adopts flush bonding processor to finish this algorithm.It also is the core place of native system.The user can select multiple different compression ratio and image size as required.

Wireless data transfer module: monitoring acquisition terminal data transmission module, its function are that the good jpeg image of compression is sent to the network of operator by built-in GPRS wireless module, and this module package has the PPP dialing, supports ICP/IP protocol and domain name mapping.

Data center server software and remote monitoring terminal software: data center server software is to operate in one to have fixed ip address or adopt on the server of domain name mapping mode the management of realization forwarding of data, image scene acquisition node.Remote monitoring terminal soft mode piece, its function are by inserting the Internet, and the management of on-site supervision terminal node is finished at the logon data center, and can display image and monitor data management on monitor, the selectivity storage that comprises image with check etc.

Wireless remote IMAQ transfer system is made up of wireless acquisition terminal, data center and client's control end according to C/S model (client/service end pattern) design.During system works, earlier start IMAQ and compression process and initiate to transmit and is connected, determine the instant transmission of image compression data bag according to the command interaction of holding with data center with the data center in a distant place by wireless acquisition terminal; Data center's end then moves with server mode, work such as reception that the transmission connection of wait distant place wireless acquisition terminal and foundation need perform the image compression data bag and decoding processing, database preservation, and transfer data to client terminal from data center on request.Simultaneously, data center can receive the order that client is sent, again command transfer to wireless acquisition terminal.

From the general angle of communication system theory, overall system can be divided into several sections: the compression of on-the-spot original image collection, original image, the wireless channel of compressing image data transmit, the database of reception, deciphering, decoding and the reception view data of center compressing image data is preserved.Before two parts belong to wireless acquisition terminal, the software that hardware of using comprising acquisition controlling and support function realize, back two parts belong to center-side, comprise hardware and corresponding software.Wherein the radio image collecting terminal hardware comprises that software promptly refers to terminal control software and image Compression software by image collection chip processor, master controller and GPRS Modem module, and these all run on on-site wireless IMAQ end host.Data center one is connected into the main frame of Internet, has fixedly public network IP address, is responsible for receiving that decompress(ion) is transmitted, carried out to the images acquired packed data that sends from the radio image collecting terminal on request and database is preserved.The wireless channel of compressing image data transmits and then relies on the data service of GPRS mobile radio communication to realize.

Whole system transmits receiving system as a cover video image acquisition, comprises following autonomous system: wireless acquisition terminal system, data center server system and customer side control system.The wireless acquisition terminal system is responsible for gathering vedio data, compressed encoded video view data, difference extraction, view data is encrypted and data encrypted is sent to the remote data center; Data center's end system be responsible for to the compressed video image data that receives be decrypted, decoding, error image recovers and show, or finishes the storage forwarding capability according to long-range customer side software requirement.Image scene acquisition terminal system hardware part partly is made up of video image acquisition module, acquisition controlling, terminal handler part and GPRS Modem wireless transport module etc.

Image scene acquisition monitoring terminal comprises IMAQ part and GPRS network hop, and the IMAQ part is realized the digitlization conversion of analog image and realized the jpeg image compressed encoding by the special-purpose compression chip of video.The GPRS network hop is realized network transmission function by special-purpose GPRS module, and it and IMAQ interface partly are universal asynchronous serial interface (UART).Data center server partly comprises hardware and software, hardware is a PC with public network IP address, software is server program, by functions such as order transmission between data center server software realization GPRS network transport module and remote monitoring terminal and transfer of data.

Consider that radio image collecting supervisory control system transmission data are the view data after overcompression, so data volume is less, what the transmission of system diagram picture was adopted is the wider GPRS network of signal coverage rate, and what promptly use in wireless data transfer module is the GPRS module.And,, but do not influence the real-time of the image transmission that system acquisition arrives because its transmission rate is fast than GPRS for the CDMA net.According to user's needs, also can change the GPRS module into the CDMA module, to be suitable in cdma network, carrying out transfer of data.Such design also is the consideration for practicality, low cost and low-power consumption.

The dynamic detection algorithm is adopted in picture control, has only the image change system just can trigger to report to the police and the image that collects is transmitted.In transmission course, adopted the DCT territory error image transmission means of technological precedence again, the first image complete transmission that a width of cloth is collected is to after the user monitoring end, next be vicissitudinous part between transmission and last sub-picture, obtain the difference of two width of cloth images, system will only transmit the difference of this generation, recover and adopt correlation technique to carry out image at user's remote monitoring terminal, behind the certain hour, a secondary complete image is transmitted again in system at interval.The benefit of doing like this is the flow that can significantly reduce Network Transmission, thereby reduces the data traffic expense of monitoring significantly, also greatly reduces system power dissipation simultaneously, and present technique also is the main feature of system.

Total implementation framework structure as shown in Figure 2, system is that core constitutes with the ARM flush bonding processor mainly.Whole system mainly comprises flush bonding processor LPC2214, wireless GPRS communication terminal module SIM300C, serial ports expansion module, memory extensive module and the image capture module etc. of NXP company.LPC2214 communicates by UART1 and GPRS module, finishes the function of transfer of data; UART0 is used for controlling image capture module C328, finishes the control of image module and the collection of view data; Simultaneously by the serial ports of expansion finish with PC between communicate by letter, to realize the output of Debugging message; Whole system realizes the debug function of system by jtag interface.Because the LPC2214 internal memory has only 16KB, finish the storage of view data and transmit and realize simple view data processing, so need to extend out SRAM here, the memory I S61LV51216 of the 1MB of the production of employing ISSI company of system, bigger accumulator system is one and makes things convenient for the upgrading of system and finish complex calculations control and prepare.

Native system has powerful monitoring capacity, reserve a plurality of GPIO mouths at the monitoring image acquisition terminal, can be configured to input or output detection, be used for external input device (as the external infrared sensor of some customer requirements etc.) or drive outside gate inhibition's action equipment of etc.ing, with establishment supervisory control system more senior, with better function.

The form of images acquired adopts jpeg format, and the image size is multistage adjustable, and the native system ultimate resolution is 640 * 480, and this is that practicality and image definition, Network Transmission real-time etc. are taken all factors into consideration compromise result.For the IMAQ mode, system provides adjustable interval of user monitoring terminal order collection, timing acquiring and time to gather, for monitoring scheme provides great flexibility.

What the monitoring access way of system mainly adopted is that user's PC inserts monitoring, considers that present domestic cellphone subscriber group is very big, and system supports mobile phone to receive SMS alarm, and is real-time.And receive information or PDA access etc. for the Email that adopts in the other products that occurs on the market, because real-time is strong inadequately, for the consideration of practicality, native system has saved the design of this part, for the user saves cost.In addition, at present widely used immediate communication tool, system proposes meter can insert warning with immediate communication tool, makes system have stronger flexibility.

At user monitoring terminal, system can be to the image of reporting to the police full screen display and trigger audible alarm automatically when many pictures are browsed, and the image that will change warning is in time stored.Simultaneity factor can provide different access rights for different users, guarantees the fail safe of system.

Image difference extracts transmission algorithm and realizes

(1), based on the jpeg image change-detection of compression domain

1, basic principle

Front and back two width of cloth jpeg images are decoded to the DCT territory, obtaining with 8 * 8 is Y, Cb and the pairing DCT coefficient matrix of each component of Cr of unit, these data are carried out corresponding luminance texture and color feature value calculating, and the characteristic value of two frame corresponding blocks before and after the contrast is to determine the variation of jpeg image.

2, arthmetic statement

Piece with 8 * 8 is an example, the value of establishing the pixel of texture or color component be f (i, j), i=0,1 ..., 7, j=0,1 ..., 7, its corresponding DCT coefficient be f (u, v), u=0,1 ..., 7, v=0,1 ..., 7.The dct transform of two dimension is as follows:

$F(u,v)=\frac{1}{4}C\left(u\right)C\left(v\right)\×\underset{i=0}{\overset{7}{\mathrm{\Σ}}}\underset{j=0}{\overset{7}{\mathrm{\Σ}}}f(i,j)\cos \frac{(2i+1)\mathrm{u\π}}{16}\cos \frac{(2j+1)\mathrm{v\π}}{16}---\left(1\right)$

Wherein,

DCT is inversely transformed into:

$F(i,j)=\frac{1}{4}C\left(u\right)C\left(v\right)\×\underset{i=0}{\overset{7}{\mathrm{\Σ}}}\underset{j=0}{\overset{7}{\mathrm{\Σ}}}f(u,v)\cos \frac{(2i+1)\mathrm{u\π}}{16}\cos \frac{(2j+1)\mathrm{v\π}}{16}---\left(2\right)$

In general, brightness or color component have following relation [1] in 8 * 8 the mean intensity and the value of its DC coefficient: (can through type (2) derive and obtain! )

$A=\frac{1}{8\×8}\underset{i=0}{\overset{7}{\mathrm{\Σ}}}\underset{j=0}{\overset{7}{\mathrm{\Σ}}}f(i,j)=\frac{1}{8}F\left(\mathrm{0,0}\right)---\left(3\right)$

According to the Pa Saiwaer theorem, dct transform only is the distribution that changes dimensional energy, and the total amount of energy does not change, so have:

$\underset{i=0}{\overset{7}{\mathrm{\Σ}}}\underset{j=0}{\overset{7}{\mathrm{\Σ}}}{\left[f(i,j)\right]}^2=\underset{u=0}{\overset{7}{\mathrm{\Σ}}}\underset{v=0}{\overset{7}{\mathrm{\Σ}}}{[F(u,v)}^2---\left(4\right)$

The luminance texture of image block or color characteristic are:

$\mathrm{Tc}=\frac{1}{8\×8}\underset{i=0}{\overset{7}{\mathrm{\Σ}}}\underset{j=0}{\overset{7}{\mathrm{\Σ}}}{\left[f(i,j)\right]}^2-{\left[\frac{1}{8\×8}\underset{i=0}{\overset{7}{\mathrm{\Σ}}}\underset{j=0}{\overset{7}{\mathrm{\Σ}}}f(i,j)\right]}^2$

$=\frac{1}{8\×8}\underset{u=0}{\overset{7}{\mathrm{\Σ}}}\underset{v=0}{\overset{7}{\mathrm{\Σ}}}{\left[F(u,v)\right]}^2-{\left[\frac{1}{8}F\left(\mathrm{0,0}\right)\right]}^2$

$=\frac{1}{8\×8}\underset{u=0}{\overset{7}{\mathrm{\Σ}}}\underset{v=0}{\overset{7}{\mathrm{\Σ}}}{\left[F(u,v)\right]}^2,u\≠0,v\≠0---\left(5\right)$

As shown in Figure 3, the step of algorithm realization is as follows:

(1) at first last width of cloth jpeg image is decoded to the DCT territory, obtains corresponding brightness and color DCT numeric field data (3 brightness of each 8 * 8 correspondence or color component block).

(2) utilize formula (5) to calculate all 8 * 8 luminance texture and color characteristics, preserve corresponding characteristic value.

(3) a back width of cloth jpeg image is decoded to the DCT territory, obtains corresponding brightness and color DCT numeric field data, and calculate all 8 * 8 characteristic of correspondence values.

(4) luminance texture and the color feature value to all corresponding pieces of image of front and back two width of cloth compares, and the position and the quantity of record different masses.

(5) whether the position of the piece that changes of judging characteristic value concentrates on corresponding zone, determines whether the back piece image occurs changing.

As shown in Figure 4, image change difference extraction step is as follows:

1, basic principle

According to the result of previous image change-detection, the piece that luminance texture and color characteristic are changed carries out DCT territory difference and extracts, and its difference is carried out corresponding quantization, entropy coding etc.

2, arthmetic statement

If F _p(u, v) and F _c(u, two width of cloth jpeg images are decoded to the coefficient value in DCT territory before and after v) being respectively.

Algorithm steps:

(1) utilize formula (6) to obtain the variation difference in DCT territory:

Δ(u，v)＝F _c(u，v)-F _p(u，v) (6)

(2) this difference is carried out corresponding quantization, coding, add necessary information and be packaged into the JPEG code stream.

(3) decoding end need be carried out corresponding contrary the processing.

Claims (3)

1. the remote wireless image supervisory control system based on the transmission of DCT territory difference comprises image scene acquisition module, wireless data transfer module, data center server software and remote monitoring terminal software,

IMAQ compression module and wireless data transfer module are formed the on-site supervision end, finish the collection compression, encryption of image scene data etc.;

Data center server and remote monitoring end are formed client, and data center server operation service end software is wherein finished management, the data of on-site supervision node, the functions such as forwarding of order; Remote client's monitoring client software of the corresponding exploitation of remote monitoring end PC operation is finished functions such as logon data central server, picture control, order transmission;

It is characterized in that,

On-site supervision end detected image is and if only if image when changing, and the on-site supervision end just triggers reports to the police and the image that collects is transmitted; In transmission course, adopt DCT territory error image transmission means, its step is,

Steps A: give remote monitoring terminal software the image complete transmission that one width of cloth collects;

Step B: vicissitudinous part between a transmission and the last sub-picture;

Step C: obtain the difference between two width of cloth images;

Step D: will and only this difference be transmitted;

Step e: remote monitoring terminal software receives this difference and carries out image and recover;

Step F: behind the certain hour, be transferred to remote monitoring terminal software one secondary complete image more at interval;

Repeating step A is to step F.

2. the remote wireless image supervisory control system based on the transmission of DCT territory difference as claimed in claim 1 is characterized by, and whether conversion step is described detected image:

(1) with last width of cloth picture decoding to the DCT territory, obtain corresponding brightness and color DCT numeric field data;

(2) calculate all 8 * 8 luminance texture and color characteristics, preserve corresponding characteristic value;

(3) the back piece image is decoded to the DCT territory, obtains corresponding brightness and color DCT numeric field data, and calculate all 8 * 8 characteristic of correspondence values;

(4) luminance texture and the color feature value to all corresponding pieces of image of front and back two width of cloth compares, and the position and the quantity of record different masses;

(5) whether the position of the piece that changes of judging characteristic value concentrates on corresponding zone, determines whether the back piece image occurs changing.

3. the remote wireless image supervisory control system based on the transmission of DCT territory difference as claimed in claim 1 or 2, the step of obtaining the difference between two width of cloth images is:

(1) calculates the variation difference that obtains the DCT territory;

(2) this difference is carried out corresponding quantization, coding, add necessary information and be packaged into image code stream;

(3) decoding end is carried out corresponding contrary the processing.

Images