CN104284207A - Information transmission method based on video image - Google Patents

Abstract

The invention relates to an information transmission method based on a video image. The method comprises the steps that data information is encoded at a signal sending end; then a code stream obtained after encoding is modulated into the image, and video information is generated; the video information which is generated at the signal sending end is acquired by a camera arranged on equipment through a video transmission channel at a receiving end, then a received video is demodulated, and the code stream information in the image is acquired; at last, the demodulated code stream is decoded, and the transmitted data can be restored and obtained. Data transmission can be conducted only by the camera arranged on a mobile terminal, the high resolution ratio and high imaging quality are achieved, the cost is low, environmental disturbance is small, and therefore the problem that data can not be transmitted when a network and a wireless network are cut off, and a USB flash disk is not connected is solved. Accordingly, the information transmission method based on the video image can be widely applied to the data transmission field.

Description

A kind of information transferring method based on video image

Technical field

The present invention relates to a kind of information transferring method, particularly about a kind of information transferring method based on video image.

Background technology

Along with the development of the communication technology, with mobile phone, panel computer, notebook computer, MP3 player etc. for the mobile terminal of representative is widely applied.For the ease of the mutual transmission of information between mobile terminal, be developed multiple different data transfer mode.Message-switching technique between current mobile terminal mainly contains bluetooth, infrared, wifi etc., these technology are before carrying out information transmission, must through the link such as authenticating user identification, reception, and wifi cannot carry out the transmission of data under not having network or not having wireless state.

Existing transmission technology is as follows:

1) Ma Ming, Li Haibo. based on the generation of the Quick Response Code of Android and the design and implimentation .Computer Knowledge and Technology.Vol.8 of recognition system, this system of No.26.September 2012. to be resolved two-dimensional code data by Android phone and is encoded, and realizes the function that Quick Response Code generates and identifies.This system mainly comprises two parts: the generation system design of (1) two-dimensional bar code.The generation of Quick Response Code mainly utilizes corresponding encoded packets, and the character conversion that user inputs is become two-dimensional array, then according to the coding criterion of Quick Response Code, uses drawing function to draw Quick Response Code.(2) the recognition system design of two-dimensional bar code.First system gathers the image information of two-dimensional bar code by camera, then obtain the view data in camera by interface function technology.The major defect of this technology is: (1) often opens two dimensional image is all black and white image, and it represents the information of a bit with multiple pixel, therefore its information storage is very little, therefore needs very many images to carry out memory code stream information, has the lower rate of information throughput.(2) function not having information directly to transmit.

2) Zhao Lixin, Chen Hongzhou, Ge Yingjun. the method and apparatus of information code and obtaining information code is sent with audio signal.In the patent of publication number: 102522090A, propose a kind of method that audio signal sends message code.First information code and synchronous head are modulated in the audio signal of second band by the present invention; The audio signal of the second band of this modulation is directly transmitted, or transmits after the audio signal of the second band of this modulation is superposed with the audio signal of first band.At receiving terminal, the audio signal received is carried out demodulation, obtain transmitting data.

In sum, the shortcoming in the existing information technology solution taking audio frequency as carrier is mainly the interference that (1) is easily subject to ambient noise or other sound.(2) transmission rate is lower.

Summary of the invention

For the problems referred to above, the object of this invention is to provide the camera that a kind of need utilize mobile terminal device to carry, by image encoding and decoding technique, just can carry out the information transferring method based on video image of information transmission.

For achieving the above object, the present invention takes following technical scheme: a kind of information transferring method based on video image, it comprises the following steps: 1) as follows in the operation of Video coding end: 1. to be split by the code stream of data to be transmitted, and data to be transmitted packed; 2. by source encoder to packing data to be transmitted encode, generate encoded after code stream; 3. the code stream after coding is modulated in picture, produces encoded video streams; 4. by video player, the encoded video streams produced is play; 2) as follows in the operation of video decode end: 1. to adopt the video information that video receiver plays out with the speed of at least 3 times acquisition video player; 2. carry out demodulation for the video information received, obtain binary code stream information contained in video; 3. decoding is carried out to binary code stream information contained in video, the information of reduction data to be transmitted.

Described step 1) step 1. comprise the following steps: A, read the essential information of data to be transmitted, the size obtaining these data is s; B, calculate data to be transmitted and be modulated to when transmitting in the middle of picture, and set the amount of information that the most multipotency of every pictures stores wherein, W represents the width of storage information, and H represents the height of storage information; The size of the block of pixels for representative color is chosen in n × n representative; The gross information content will transmitted after C, calculation code: if coded message transfer rate is e, then the information size will transmitted after coding is B=s/e; Amount of information l contained by D, the total N of the picture of calculating needed for data to be transmitted and last picture: if B%A==0, then the number transmitting picture total is N=B/A, and the size of the storage information of last picture is l=B; Otherwise N=B/A+1, l=A-(N-1) * B; E, by data to be transmitted with every pictures size for A packs.

Described step 1) step 2. in packing data to be transmitted carry out LDPC message sink coding.

Described step 1) step 3. in, comprise the following steps: A, by the picture sum N and the amount of information l of last picture needed for data to be transmitted, open in synchronous picture stored in the N for transmitting; B, in synchronous picture, add training information; C, by coding generate code stream stored in synchronous picture; D, by the picture of coding with fixed rate stored in video, this fixed rate determines by data volume waiting for transmission with for the resolution of the picture that transmits data.

The present invention is owing to taking above technical scheme, it has the following advantages: 1, the invention provides a kind of new information transmission mode, by being that carrier transmits various different data with video, the camera that only mobile terminal need be utilized to carry just can carry out the transmission of data, there is very high resolution and image quality, and with low cost, environmental interference is little, with this solve suspension, disconnected wireless, do not connect the problem that USB flash disk just can not transmit data.Image used when 2, encoding in the present invention is colour picture, compares the bianry image that Quick Response Code is used, and information storage of the present invention is large, and can reduce transmission is the required total number of picture, effectively improves the efficiency of transmission of data.3, at signal receiving end, the present invention utilizes the size of each colouring information proportion in total colouring information to represent that this information is the probability of 1, this information is input to source coding, the decoding arbitration schemes of this soft input/soft output can improve the decoding performance of decoder, significantly can reduce the error rate of transfer of data.Therefore, the present invention can be widely used in field of data transmission.

Accompanying drawing explanation

Fig. 1 is schematic flow sheet of the present invention

Fig. 2 is Video coding theory diagram

Fig. 3 is encoded picture format pattern diagram

Fig. 4 is video pre-filtering flow chart

Fig. 5 is the spatial mappings schematic diagram at control point

Embodiment

Below in conjunction with drawings and Examples, the present invention is described in detail.

The principle of the invention is as follows: first encoded by data message at signal sending end; Then the code stream after coding is modulated in image, produces video information; By transmission of video passage, in the video information of the camera acquisition transmitting terminal generation that receiving terminal utilizes equipment to carry, then demodulation is carried out to the video received, obtain the code stream information in image; Finally decoding is carried out to the code stream of demodulation, just the reducible data obtaining transmitting.

As shown in Figure 1, a kind of information transferring method based on video image, it comprises the following steps:

1) as follows in the operation of Video coding end (information transmitting terminal):

As shown in Figure 2,1. split by the code stream of data to be transmitted, and data to be transmitted packed, it comprises the following steps:

A, read data to be transmitted type of coding, data are first-class well known to a person skilled in the art essential information, the size obtaining these data is s (bit);

B, calculate data to be transmitted and be modulated to when transmitting in the middle of picture, the amount of information that the most multipotency of every pictures stores wherein, the size of the block of pixels for representative color is chosen in n × n representative, and specify that the picture size of every pictures storage information is W × H (namely resolution is W × H), wherein W represents the width of storage information, and H represents the height of storage information;

Picture can adopt black and white image and gray level image two kinds, and black and white image utilizes the gray level image of two gray scales to carry out memory code stream information, and gray level image utilizes its different grey-scale to carry out memory code stream information.

In the present embodiment, employing black and white image is described: for a width picture, its resolution is W × H, utilizes small pixel block wherein to represent a kind of color, adopts different colours to represent bit information, namely the bit stream of transmission information is carried out by color, W=640, H=768, and adopt 16 pixels of 4 × 4 to represent a kind of color, represent bit information by red, green, blue, Bai Si kind color, often kind of color represents 2 bits.Wherein represent 11 by redness, green represents 10, and blueness represents 01, and white represents 00, therefore the amount of information that stores of the most multipotency of every pictures more color memory code stream information can certainly be adopted, to remember the information storage not increasing every pictures, improve the efficiency of transmission of information.

The gross information content will transmitted after C, calculation code: if coded message transfer rate is e, then the information size will transmitted after coding is B=s/e (bit);

Amount of information l contained by D, the total N of the picture of calculating needed for data to be transmitted and last picture: if B%A==0 (remainder is 0), then the number transmitting picture total is N=B/A, and the size of the storage information of last picture is l=B; Otherwise N=B/A+1, l=A-(N-1) * B, and by needed for data to be transmitted picture sum N and last picture contained by amount of information l be sent to step 3.;

E, by data to be transmitted with every pictures size for A packs, namely corresponding all data flow correspondences of every pictures are packaged into each self-corresponding packet;

2. by source encoder to packing data to be transmitted carry out LDPC (Low Density Parity Check Code, low density parity check code) message sink coding, generate encoded after code stream, it comprises the following steps:

A, get k bit information code at every turn encode for the data to be transmitted after packing, because code rate is e, coding generation bit number n=k/e.In the present embodiment, k=960, code rate e=16/18, therefore n=k/e=1080.

B, be constructed as follows the check matrix of matrix as LDPC code of biconjugate corner structure:

$H=\left[p_1\right|p_2]=\left[\begin{array}{cccccccccc}{p}_{\mathrm{1,1}}& p_{\mathrm{1,2}}& ...& p_{1,k}& h\left(1\right)& 1& 0& ...& 0& 0\\ p_{\mathrm{1,2}}& p_{\mathrm{2,2}}& ...& p_{2,k}& h\left(2\right)& 1& 1& ...& 0& 0\\ p_{\mathrm{3,1}}& p_{\mathrm{3,2}}& ...& p_{3,k}& h\left(3\right)& 0& 1& ...& 0& 0\\ \·& \·& & \·& \·& \·& \·& & \·& \·\\ \·& \·& ...& \·& \·& \·& \·& ...& \·& \·\\ \·& \·& & \·& \·& \·& \·& & \·& \·\\ p_{n-k-\mathrm{1,1}}& p_{n-k-\mathrm{1,2}}& ...& p_{n-k-1,k}& h(n-k-1)& 0& 0& ...& 1& 1\\ p_{n-k,1}& p_{n-k,2}& ...& p_{n-k,k}& h(n-k)& 0& 0& ...& 0& 1\end{array}\right]---\left(1\right)$

Wherein, p ₁represent the matrix of (n-k) × k, p ₂represent the matrix of one (n-k) × (n-k), h (1)=h (n-k)=1, for 1 < i < n-k, in { h (i) }, have an element value to be 1.

C, establish u=(u ₁, u ₂..., u _k) be information group, v=(v ₁, v ₂..., v _n) be the code word obtained after LDPC coding,

According to vH ^t=0, then have

$\left\{\begin{array}{c}{\mathrm{\&Sigma;}}_{j=1}^k{p}_{1,j}{u}_j+v_{k+1}+v_{k+2}=0;\\ {\mathrm{\&Sigma;}}_{j=1}^k{p}_{i,j}+h\left(i\right)v_{k+1}+v_{k+i}+v_{k+i+1}=\mathrm{0,2}\&le;i\&le;n-k-1;\\ {\mathrm{\&Sigma;}}_{j=1}^k{p}_{n-k,j}{u}_j+v_{k+1}+v_n=0;\end{array}\right.---\left(2\right)$

Can obtain from formula (2)

$v_{k+1}=\underset{i=1}{\overset{n-k}{\mathrm{\&Sigma;}}}\underset{j=1}{\overset{k}{\mathrm{\&Sigma;}}}{p}_{i,j}{u}_j---\left(3\right)$

D, according to formula (2) and (3), forward-backward recutrnce computing is used to obtain successively:

concrete recursive operation process prescription is as follows:

I, forward recursive: for v _irecursive operation expression formula is:

II, backward recursive: for v _irecursive operation expression formula is:

E, by above several step by k bit information code, coding generate n code word, stored in coded data.Repeat steps A) ~ E), until the LDPC coding of all package information stream all completes.

It should be noted that, the present invention, except LDPC message sink coding, can also adopt and anyly has the coded system of error correction and improve one's methods.

3. be modulated in picture by the code stream after coding, produce encoded video streams, it comprises the following steps:

A, by the picture sum N and the amount of information l of last picture needed for data to be transmitted, stored in synchronous picture, synchronous picture is the N pictures for transmitting;

In the present embodiment, get the information of 2 bits, if 4 × 4 16 pixel values are all set to redness by 11 at every turn; If 4 × 4 16 pixel values are all set to green by 10; If 4 × 4 16 pixel values are all set to blueness by 01; If 4 × 4 16 pixel values are all set to white by 00.

B, have misalignment in the transmission due to image, therefore the method for setting threshold is adopted: setting lower threshold and upper limit threshold, be less than lower threshold and be judged to 0, be greater than upper limit threshold and be judged to 1, training information (threshold value of setting) is added in synchronous picture, carrying out auxiliary video decoding end calculating bit is the probability of 1, improves the accuracy rate of signal receiving output information, thus improves the reliability of transfer of data;

In the present embodiment, 1 ~ 4 row in synchronous picture, is adopted to store the information of N and l.Ensuing 5 ~ 8 row of the present embodiment are all set to redness, and 9 ~ 12 row are all set to green, and 13 ~ 16 row are all set to blueness, as training information during decoding.Other place of synchronous picture is all set to white.

C, by coding generate code stream stored in synchronous picture;

As shown in Figure 3, for enabling to be relatively easy to during decoding obtain area-of-interest, add white frame in the surrounding of picture, the pixel value by t around picture (in the present invention, t value is 4) bit is all set to white.Above image information stores, add 4 row additional spaces again, store the number information of every pictures, as shown in Figure 3, wherein the size of encoded picture should be (W+t*2) × (H+t*2+4) to its general layout simultaneously.Successively by the coded information stream of source encoder gained stored in picture, information storage rule is with reference to steps A, to N, (what be stored into coded information stream at first is picture 1 to picture number information 1 simultaneously, arrive picture N by that analogy) add the position of the number information shown in Fig. 4 successively to, thus obtain the picture of encoding.

D, by the picture of coding with the speed of 10fps (Frames Per Second, transmission frame number per second) stored in video, this speed determines by data volume waiting for transmission with for the resolution of the picture that transmits data.

4. by video player, the encoded video streams produced is play video with the speed of 10fps.

2) as follows in the operation of video decode end (information receiving end):

1. camera is adopted to obtain the video information of the 10fps that video player plays out with the speed of 30fps.Video rate due to receiving terminal is three times that play end, and therefore, play a pictures of end, receiving terminal can obtain three.

2. as shown in Figure 4, carry out demodulation for the video information received, obtain binary code stream information contained in video, its step is as follows:

A, image denoising (Image semantic classification);

The coloured image of acquisition is directly converted to gray level image, carries out simple fixed threshold binaryzation, the pixel value of the gray scale picture obtained is greater than 180 all become 255, otherwise be 0.So far, the bianry image of Video coding end white frame clear-cut can just be obtained.

B, image Corner Detection;

I, bianry image contours extract: classical edge extracting method is Edge Detection Local Operator method, and the present invention utilizes the single order of grey scale change in each pixel neighborhoods or the Changing Pattern of the second order number of plies to carry out rim detection.Adopt Laplacian to carry out rim detection to bianry image in the present invention, obtain profile information preferably.Laplace filter is by the second-order differential of binary function, if binary function image is expressed as f (x, y), then its Laplace transform is defined as:

${\&dtri;}^{2}f=\frac{{\&PartialD;}^{2}f}{{\&PartialD;x}^2}+\frac{{\&PartialD;}^{2}f}{{\&PartialD;y}^2}---\left(6\right)$

For digital picture, its discrete form can be obtained.Laplce's discrete form is many, the present invention just wherein a kind of form be introduced, its expression formula is:

${\&dtri;}^{2}f=[f(x+1,y)+f(x-1,y)+f(x,y+1)+f(x,y-1)]-4f(x,y)---\left(7\right)$

Thus obtain the contour curve of area-of-interest.

II, image Corner Detection: four summits that only need obtain the white frame coded by coded image, the angle therefore by calculating angle point both sides contour curve discrete point just can obtain the angular coordinate of contour curve.

C, image rectification;

Information transmission scheme based on video is the scheme obtaining information in another mobile phone with cell-phone camera, in the video capture stage, inevitably has the problem of image inclination.The present invention mainly utilizes control point converter technique to carry out image rectification, the spatial mappings figure (as shown in Figure 5) of control point conversion: quadrangle summit maps directly on corresponding volume rectangle summit, and the point inputting quadrangle inside is then mapped on the point of corresponding rectangle inside.

I, bilinear space conversion expression formula is:

$\left\{\begin{array}{c}u=\mathrm{Ax}+\mathrm{By}+\mathrm{Cxy}+D\\ v=\mathrm{Ex}+\mathrm{Fy}+\mathrm{Gxy}+H\end{array}\right.---\left(8\right)$

To given input picture and output image, the transform defined can be write as matrix form:

Therefore the point of given 4 points and corresponding transformation space thereof, just can obtain 8 linear equations, as long as all any three points are not wherein point-blank, just can solve 8 transformation parameters.Thus obtain the relation of input picture and output image.

In above-described embodiment, utilize control point converter technique to carry out image rectification, the image rectification method under perspective transform method and non-calibration point can also be adopted.

II, by gray-level interpolation, correcting image is made to keep continuity and connectedness.For bianry image, the method for bilinear interpolation is used to obtain correcting image.

The computing of bilinear interpolation can be expressed as:

$\begin{array}{c}g(u,v)=[f(x+1,y)-f(x,y)]x+[f(x,y+1)-f(x,y)]y+\\ [f(x+1,y+1)+f(x,y)-f(x,y+1)-f(x+1,y)]\mathrm{xy}+f(x,y)\end{array}---\left(10\right)$

More namely gray value wants right space change point adjacent four pixel values to decide.

After image after III, acquisition correct, image size is adjusted to the size of coded image.

The code stream information of D, acquisition area-of-interest;

Judge photo current whether as synchronous picture (synchronous picture is the code stream information of area-of-interest), if 1 ~ 4 row has information in photo current, 5 ~ 8 row are red entirely, 9 ~ 12 row are green entirely, 13 ~ 16 row are blue entirely, other place of picture is all white, then photo current is synchronous picture; Otherwise continue to read in next pictures, repeat step D, until find synchronous picture.

E, the information obtained in synchronous picture: by calculating the ratio of each color component, obtain the probabilistic information that each bit is 1, using the input code flow information that this probabilistic information is decoded as LDPC, improved the performance of decoding like this by input Soft Inform ation, improve the reliability of transfer of data further.

First information N and the l of 1 ~ 4 row in picture is obtained.Due to picture to be taken by mobile phone camera after color have distortion, calculate the color component ratio of the training information in synchronous picture, as the reference of decoded portion below, concrete scheme is: count respectively red obtain after video channel three color component value sumRr, sumRg, sumRb, three color component value sumBr of three green color component value sumGr, sumGg, sumGb and blueness, sumBg, sumBb.

Corresponding with coding side, during coding the present embodiment with redly representing 11, greenly represent 10, indigo plant represents 01, represents 00 in vain, therefore can be red and green during first bit 1, can be red and blue when second bit is 1, and calculating first bit in redness is respectively the probability of 1 second bit is the probability of 1 in green, first bit is the probability of 1 $p_{g1}=\frac{\mathrm{sumGr}+\mathrm{sumGg}}{\mathrm{sumGr}+\mathrm{sumGg}+\mathrm{sumGb}},$ Second bit is the probability of 1 $p_{g2}=\frac{\mathrm{sumGr}+\mathrm{sumGb}}{\mathrm{sumGr}+\mathrm{sumGg}+\mathrm{sumGb}};$ In green, first bit is the probability of 1 second bit is the probability of 1 $p_{b2}=\frac{\mathrm{sumBr}+\mathrm{sumBb}}{\mathrm{sumBr}+\mathrm{sumBg}+\mathrm{sumBb}}.$

F, obtain synchronous pictorial information after, read video picture below, until obtain the picture that three are numbered 1, due in shooting process, it is stand-by that each numbering all takes 3 pictures, thus to find three be numbered 1 picture.Because first and the 3rd pictures can because the impact of image conversion have ghost image, in the middle of therefore selecting, the second pictures is as decoding picture.

G, from image, read the RGB component information of each pixel, known to form during coding, during coding, represent 2 bits by 4 × 4 16 pixels, redly represent 11, greenly represent 10, indigo plant represents 01, represents 00 in vain.Therefore, by adding up the color component of 16 pixels of 4 × 4, the total amount sumR of RGB information in pixel, the value of sumG, sumB is obtained respectively.First by judging the value of sumR, sumG, sumB, if three ratios be worth are all about 1, judge that these 16 pixels are as white, therefore two bits be 1 probability be all almost 0, by 00 stored in decoded file.Otherwise calculate value, then calculate the principal component in RGB three kinds of components respectively, if principal component be redness, namely the value of sumR is maximum, and value is more much larger than sumG, sumB, then the value calculated, then through type (11) and (12) calculate two bits is respectively the probability of 1:

$\left\{\begin{array}{c}{p}_1=\frac{{\hat{p}}_1}{p_{r1}},0<\frac{{\hat{p}}_1}{p_{r1}}<1\\ p_1=1,\frac{{\hat{p}}_1}{p_{r1}}\&GreaterEqual;1\end{array}\right.---\left(11\right)$

$\left\{\begin{array}{c}{p}_2=\frac{{\hat{p}}_2}{p_{r2}},0<\frac{{\hat{p}}_2}{p_{r2}}<1\\ p_2=1,\frac{{\hat{p}}_2}{p_{r2}}\&GreaterEqual;1\end{array}\right.---\left(12\right)$

If principal component is green, then through type (13) and (14) calculate two bits is respectively the probability of 1:

$\left\{\begin{array}{c}{p}_1=\frac{{\hat{p}}_1}{p_{g1}},0<\frac{{\hat{p}}_1}{p_{g1}}<1\\ p_1=1,\frac{{\hat{p}}_1}{p_{g1}}\&GreaterEqual;1\end{array}\right.---\left(13\right)$

$\left\{\begin{array}{c}{p}_2=\frac{{\hat{p}}_2}{p_{g2}},0<\frac{{\hat{p}}_2}{p_{g2}}<1\\ p_2=1,\frac{{\hat{p}}_2}{p_{g2}}\&GreaterEqual;1\end{array}\right.---\left(14\right)$

If principal component is blue, then through type (15) and (16) calculate two bits is respectively the probability of 1:

$\left\{\begin{array}{c}{p}_1=\frac{{\hat{p}}_1}{p_{b1}},0<\frac{{\hat{p}}_1}{p_{b1}}<1\\ p_1=1,\frac{{\hat{p}}_1}{p_{b1}}\&GreaterEqual;1\end{array}\right.---\left(15\right)$

$\left\{\begin{array}{c}{p}_2=\frac{{\hat{p}}_2}{p_{b2}},0<\frac{{\hat{p}}_2}{p_{b2}}<1\\ p_2=1,\frac{{\hat{p}}_2}{p_{b2}}\&GreaterEqual;1\end{array}\right.---\left(16\right)$

By the probability calculated stored in decoded file.Return step F), obtain the picture being numbered 2 to N successively, obtain the information in picture.By the decoded file Soft Inform ation obtained, be input to source decoder.

3. carry out decoding to binary code stream information contained in video, the information of reduction data to be transmitted, its step is as follows:

A, BP decoding algorithm is the decoding algorithm based on symbol Maximize criterion foundation one by one.

From step 2) 2. in the code stream that obtains, get n number at every turn and carry out decoding y=(y ₁, y ₂..., y _n).

B, first calculate the posterior probability that each bit is 1.The reliability based on log-likelihood ratio is adopted to measure in the present invention, that is:

$L\left(v_j\right|y)=\log \left(\frac{\mathrm{Pr}(v_j=0|y)}{\mathrm{Pr}(v_j=1|y)}\right)---\left(17\right)$

Obtain the LLR ratio that each bit is 1.

C, meet h to all _iji and j of=1, makes L _{j → i}=L _j.

D, check-node upgrade

To each check-node, calculate it according to formula (18) and export external information,

$L_{i\&RightArrow;j}=2{\tanh }^{-1}\left(\underset{j^{\&prime;}\&Element;N\left(i\right)\backslash j}{\&prod;}\tanh \left(\frac{1}{2}{L}_{j^{\&prime;}\&RightArrow;i}\right)\right)---\left(18\right)$

E, variable node upgrade

To each variable node, calculate it according to formula (19) and export external information

$L_{j\&RightArrow;i}=L_j+\underset{i^{\&prime;}M\left(j\right)\backslash i}{\mathrm{\&Sigma;}}{L}_{i^{\&prime;}\&RightArrow;j}---\left(19\right)$

F, decoding judgement

Calculate the total message of variable node: each variable node is calculated

$L_j^{\mathrm{Total}}=L_j+\underset{i^{\&prime;}\&Element;M\left(j\right)}{\mathrm{\&Sigma;}}{L}_{i^{\&prime;}\&RightArrow;j}---\left(20\right)$

Hard decision:

${\hat{v}}_j=\left\{\begin{array}{c}1,L_j^{\mathrm{Total}}<0\\ 0,L_j^{\mathrm{Total}}\&GreaterEqual;0\end{array}\right.---\left(21\right)$

If G obtains meet or reach maximum iteration time, then stop decoding; Otherwise, return step D) and continue iteration.

H, by will input n Soft Inform ation, decoding generation k variable node information, by decode results stored in output file.Repeat steps A) ~ H), until all information decodings complete, restoring data, so far complete with video is that carrier is to transmit various different data, the camera that only equipment need be utilized to carry just can carry out the transmission of data, solve suspension, disconnected wireless, do not connect the problem that USB flash disk just can not transmit data.

The various embodiments described above are only for illustration of the present invention; wherein the structure of each parts, connected mode and manufacture craft etc. all can change to some extent; every equivalents of carrying out on the basis of technical solution of the present invention and improvement, all should not get rid of outside protection scope of the present invention.

Claims (5)

1., based on an information transferring method for video image, it comprises the following steps:

1) as follows in the operation of Video coding end:

1. the code stream of data to be transmitted is split, and data to be transmitted is packed;

2. by source encoder to packing data to be transmitted encode, generate encoded after code stream;

3. the code stream after coding is modulated in picture, produces encoded video streams;

4. by video player, the encoded video streams produced is play;

2) as follows in the operation of video decode end:

1. the video information that video receiver plays out with the speed of at least 3 times acquisition video player is adopted;

2. carry out demodulation for the video information received, obtain binary code stream information contained in video;

3. decoding is carried out to binary code stream information contained in video, the information of reduction data to be transmitted.

2. a kind of information transferring method based on video image as claimed in claim 1, is characterized in that: described step 1) step 1. comprise the following steps:

The essential information of A, reading data to be transmitted, the size obtaining these data is s;

B, calculate data to be transmitted and be modulated to when transmitting in the middle of picture, and set the amount of information that the most multipotency of every pictures stores wherein, W represents the width of storage information, and H represents the height of storage information; The size of the block of pixels for representative color is chosen in n × n representative;

The gross information content will transmitted after C, calculation code: if coded message transfer rate is e, then the information size will transmitted after coding is B=s/e;

Amount of information l contained by D, the total N of the picture of calculating needed for data to be transmitted and last picture: if B%A==0, then the number transmitting picture total is N=B/A, and the size of the storage information of last picture is l=B; Otherwise N=B/A+1, l=A-(N-1) * B;

E, by data to be transmitted with every pictures size for A packs.

3. a kind of information transferring method based on video image as claimed in claim 1, is characterized in that: described step 1) step 2. in LDPC message sink coding is carried out to the data to be transmitted of packing.

4. a kind of information transferring method based on video image as claimed in claim 2, is characterized in that: described step 1) step 2. in LDPC message sink coding is carried out to the data to be transmitted of packing.

5. a kind of information transferring method based on video image as described in claim 2 or 4, is characterized in that: described step 1) step 3. in, comprise the following steps:

A, by the picture sum N and the amount of information l of last picture needed for data to be transmitted, open in synchronous picture stored in the N for transmitting;

B, in synchronous picture, add training information;

C, by coding generate code stream stored in synchronous picture;

D, by the picture of coding with fixed rate stored in video, this fixed rate determines by data volume waiting for transmission with for the resolution of the picture that transmits data.