CN103593131A - Touch track tracking method - Google Patents

Abstract

The invention discloses a touch track tracking method and relates to the technical field of the touch tracking technology. The touch track tracking method is used for touch screens and aims at improving writing effects and user experience of the touch screens. The touch track tracking method comprises the following steps of A, sequentially correlating touch points in first q frames which comprise a current frame, recording coordinates of the touch points in the first q frames and enabling q to be not more than 2; B, obtaining coordinates of touch points in a next frame; C, obtaining an optimal assembly between the touch points of the current frame and the touch points of the next frame according to information of the touch points of a plurality of continuous touch points; D, correlating the touch points of the current frame and the touch points of the next frame according to an assembling mode in the optimal assembly; E, outputting a correlated track of the current frame and the next frame and recording the coordinates of the touch points of the next frame; F, returning to the step B.

Description

A kind of touch track tracking

Technical field

The present invention relates to touch control technical field, relate in particular to a kind of touch track tracking.

Background technology

Along with the development of multimedia technology, touch control technology has become the hot spot technology in current man-machine interaction.The mode of the man-machine interaction of many products (as keyboard, the mouse etc.) control technology that is all touched gradually replaces.

In the various application of touch control technology, user wishes that computing machine can understand user's various touch operation conventionally, thereby understands user view and make rapidly corresponding response, and then provides convenient, intelligent service for user.User is a kind of conventional touch operation by touch objects such as finger, writing pencils touching detection surface sliding, in this case, machine judges the operation of user's pre-execution by analyzing the motion track of touch objects on touch-screen, can carry out correct tracking relationship to the movement locus of touch objects and can correctly respond user's operation to machine, so it is extremely important correctly to catch, trace into the track of touch objects.

For single-point touches, shield, when touch objects is moved on touch-screen, machine is by two frames (or former and later two scan periods before and after associated, or former and later two moment) touch point just can correctly obtain the movement locus of touch point, but the increase of counting along with touch, front and back two frames (or former and later two scan periods, or former and later two moment) touch point is all one incessantly, cannot be directly to front and back two frames (or former and later two scan periods, or former and later two moment) man-to-man association is carried out in touch point, therefore cannot obtain the correct track of touch objects.

In current multiple spot track following, a kind of common method of carrying out touch point tracking is front and back two interframe touch point minimum euclidean distance matching methods, for all touch points of k-1 frame, in all touch points of k frame, search for the nearest touch point of Euclidean distance and carry out association, as two touch points in identical strip path curve.This method is simple, real-time is very good, but this method only used before and after relation between the touch point of two frames, based on local optimum, as shown in Figure 1a, in figure, solid line is actual track, dotted line is the track of following the tracks of according to the method for prior art, when two touch objects 101, 102 when touch-surface 103 quick sliding, if followed the tracks of according to front and back two frame minimum Eustachian distance matching methods, touch objects 102 ' nearest in touch objects 101 and a rear frame in k-1 frame, touch objects 101 and touch objects 102 ' should be identified as to 2 points on a track, touch objects 102 and touch objects 101 ' are identified as to 2 points on another track, and in fact the track of two touch objects should be parallel (realization in Fig. 1 a), but be tracked as the track (dotted line in Fig. 1 a) of intersection, occurred that track crosstalks.Equally, when having two touch objects 101,102 in touch-surface 103 crisscross motion, there will be mistake as shown in Figure 1 b, be about to the original track (solid line in Fig. 1 b) intersecting and be tracked as parallel track (dotted line in Fig. 1 b), so traditional touch tracking Bu Shi global optimum, and easily occur the problem that track is crosstalked, writing effect and user's impression are all poor.

Summary of the invention

For the defect existing in prior art, technical matters to be solved by this invention is to provide a kind of touch track tracking that can improve writing effect and user's impression.

For solving the problems of the technologies described above, the technical solution used in the present invention is as follows:

A tracking, comprises the following steps:

A, by comprising present frame, in interior front q frame, carry out association in each touch point successively, and the coordinate of each touch point of q frame before record, wherein q >=2;

B, obtain the coordinate of each touch point of next frame;

C, according to the information of continuous multiple frames touch point, obtain the optimum combination between each touch point of present frame and each touch point of next frame;

D, according to the array mode in described optimum combination, each touch point of present frame is carried out associated with each touch point of next frame;

Track after E, output present frame and each touch point of next frame are associated, records the coordinate of each touch point of next frame;

F, return to step B.

Preferably, the method for obtaining the optimum combination between each touch point of present frame and each touch point of next frame described in is specially:

According to continuously selecting the optimum combination between each touch point of present frame and each touch point of next frame the direction continuity of a frame and speed continuity, likely combining between each touch point of present frame and each touch point of next frame in identical strip path curve, a >=3 wherein.

Preferably, note present frame is k frame, each execution of step E, the numerical value of k adds 1, for described each combination in likely combining, a touch point in k frame/the k+1 frame is at most only associated with a touch point in k+1 frame/the k frame, wherein k >=2.

Preferably, a=3.

Preferably, in step C, the vectorial S by touch point from k-1 frame to touch point in k frame _kwith the vectorial S of touch point from k frame to touch point in k+1 frame _k+1angle theta and direction weights omega ₁determine described direction continuity; And/or by touch point from k-1 frame the distance s to touch point in k frame _kwith the distance s of touch point from k frame to touch point in k+1 frame _k+1and speed weights omega ₂determine described speed continuity.

Preferably, the method for obtaining the optimum combination between each touch point of k frame and each touch point of k+1 frame in step C is specially:

B1, according to the described direction continuity of continuous 3 frames in identical strip path curve and described speed continuity, set up the coherent function in following path:

$f(p_i^{k-1},p_i^k,p_i^{k+1})={\mathrm{\ω}}_1(1-\cos \mathrm{\θ})+{\mathrm{\ω}}_2(1-2\frac{\sqrt{s_k{s}_{k+1}}}{s_k+s_{k+1}})={\mathrm{\ω}}_1(1-\frac{S_k\·S_{k+1}}{s_k{s}_{k+1}})+{\mathrm{\ω}}_2(1-2\frac{\sqrt{s_k{s}_{k+1}}}{s_k+s_{k+1}})$

Wherein, for i bar track, i=1,2 ..., n, n is the number of track in k frame, S _kfor the vector of touch point from k-1 frame to touch point in k frame, S _k+1for the vector of touch point from k frame to touch point in k+1 frame, θ is vectorial S _kwith vectorial S _k+1angle, ω ₁for direction weight, ω ₂for speed weight, and ω ₁+ ω ₂=1, s _kfor the distance of touch point from k-1 frame to touch point in k frame, s _k+1be in k frame touch point to the distance of touch point in k+1 frame;

B2, for described each combination in likely combining, calculate the coherent functional value in path of every track, and calculate each track the coherent functional value in path and;

B3, the described coherent functional value in path of choosing described each track in likely combining and minimum a kind of as the optimum combination between each touch point of k frame and each touch point of k+1 frame.

Preferably, the coherent functional value in described path and by average, mean square value or the root-mean-square value of the coherent functional value in path, replaced.

Preferably, ω ₁span be 0.2 to 0.7, ω ₂span be 0.3 to 0.7.

Preferably, after step e, also comprise the step that judges whether that new track adds, concrete grammar is:

For k frame touch point, judge and in k+1 frame, whether have the not associated touch point not being associated with touch point in k frame, if exist, judge this not associated touch point whether successively k+2 frame ..., associated in k+t frame, the starting point that if so, the not associated touch point in k+1 frame is new track, this corresponding track in not associated touch point is followed the tracks of, otherwise, abandon this not associated touch point, wherein 2≤t≤5.

Preferably, after step e, also comprise the step that judges whether that track finishes, concrete grammar is:

For k frame touch point, judge and in k frame, whether have the touch point not being associated with touch point in k+1 frame, if, Continuous Tracking t frame, judges the later continuously number of the whether no more than k+1 frame of the number touch point of touch point in t frame of k+1 frame, if, in k frame, the not associated corresponding track in touch point finishes, otherwise, return to step B and proceed to follow the tracks of, wherein 2≤t≤5.

Preferably, q=2, adopts with the following method association is carried out in the touch point between the front cross frame of track:

Obtain in the first frame the coordinate of each touch point in each touch point and the second frame;

In each touch point of the second frame, in search and the first frame, the touch point of first touch point Euclidean distance minimum, carries out association by these two touch points;

In the not associated touch point of the second frame, in search and the first frame, the touch point of not associated touch point Euclidean distance minimum, carries out association by these two touch points;

Judge that whether the touch point in the first frame or the second frame is all associated, if so, next frame touch point is followed the tracks of, if not, return to previous step.

The touch track tracking that the embodiment of the present invention provides, according to the acquisition of information present frame between continuous multiple frames touch point and the optimum combination between next frame, especially pass through former frame, speed continuity between present frame and next frame and direction continuity are set up the coherent function in path of every track, in likely combining between two frames of front and back, the coherent function sum minimum of path selection is a kind of as optimum combination, this method is generally difficult for the characteristic of sudden change according to the movement velocity of touch objects and velocity variations, consider the kinetic characteristic of continuous several frames touch point, optimum combination before and after obtaining the in the situation that of can there is a plurality of touch point in every frame between two frame touch points, there is good robustness, can greatly improve the writing effect of touch-screen, improve user's impression.

Accompanying drawing explanation

Fig. 1 a and Fig. 1 b are respectively touch track in prior art and follow the tracks of the two kinds of wrong situations that occur;

Fig. 2 is the touch track trace flow figure of the first embodiment of the present invention;

Fig. 3 is the process flow diagram to front cross frame track following;

Fig. 4 is the associated situation schematic diagram of front cross frame touch point;

Fig. 5 is that the direction of continuous three frames on i bar track changes (with vector angle, representing) and rate variation (representing by variable in distance) schematic diagram;

Fig. 6 is that k frame and k+1 frame respectively have six kinds in the situation of three touch points likely to combine schematic diagram;

Fig. 7 is the process flow diagram of the optimum combination between each touch point of two frames before and after obtaining;

Fig. 8 a and Fig. 8 b are respectively the schematic diagram that whether has new trajectory generation in k+1 frame, and wherein, Fig. 8 a for producing the schematic diagram of new track in k+1 frame; Fig. 8 b for not producing the schematic diagram of new track in k+1 frame;

Fig. 9 a and Fig. 9 b are respectively the schematic diagram that whether has track to finish in k+1 frame; Wherein Fig. 9 a is the schematic diagram that has track to finish in k+1 frame; The schematic diagram of Fig. 9 b for not having track to finish in k+1 frame.

Embodiment

Below in conjunction with embodiment and accompanying drawing, technical scheme of the present invention is clearly and completely described.

The invention provides a kind of touch track tracking, be applicable to various touch-screens, as optical touch screen and infrared touch panel etc.In order to narrate conveniently, the present invention is described as two touch points and is associated being positioned at two touch points in identical strip path curve in two continuous frames, " being associated " of mentioning in the present invention or " carrying out association " refer to two touch points in two frames of front and back are identified as to two points in identical strip path curve, if a touch point of former frame is associated with a touch point of a rear frame, these two touch points belong to identical strip path curve so.

The first embodiment

As shown in Figure 2, the process flow diagram of the touch track tracking providing for present embodiment, said method comprising the steps of:

Step 1: the first frame and each touch point in the second frame are carried out associated, as shown in Figure 3, can adopt minimum Eustachian distance matching method to carry out association to front cross frame touch point, be specially:

11: obtain each touch point coordinate in the first frame and the second frame.

In present embodiment, obtain touch point seat calibration method in each frame and can adopt any one method of the prior art, as for infrared touch panel, can be by the scan-data gathering be processed, obtain accurate touch point set (likely touch point set of institute), checkpoint set, removes terrible point according to the relation of the set of accurate touch point and checkpoint set, thereby obtains touch point coordinate, for optical touch screen, the mode that can process by image is obtained touch point coordinate.

12: in each touch point of the second frame, in search and the first frame, the touch point of first touch point Euclidean distance minimum, carries out association by two touch points of this Euclidean distance minimum, be about to this two touch point and link together as two points on article one track.

13: in the not associated touch point of the second frame, the touch point of not associated touch point Euclidean distance minimum in search and the first frame, association is carried out in two touch points of this Euclidean distance minimum, be about to these two touch points and link together as two points on second track.

14: judge that whether the touch point in the first frame or the second frame is all associated, if so, follow the tracks of next frame touch point, if not, return to step 13.

As shown in Figure 4, be the associated situation schematic diagram of front cross frame touch point, in the first frame and the second frame, respectively there are three touch points, according to the method described above, for first touch point A in the first frame ₁, in the second frame, search touch point A ₂with touch point A ₁euclidean distance nearest, by the touch point A in the first frame ₁with the touch point A in the second frame ₂associate, connect into a track; For second touch point B in the first frame ₁, in remaining two touch points of the second frame, search touch point B ₂with touch point B ₁euclidean distance nearest, by the touch point B in the first frame ₁with the touch point B in the second frame ₂associate, connect into a track; Because neutralizing in the second frame, the first frame respectively remains a touch point, therefore by the touch point C in the first frame ₁with the touch point C in the second frame ₂associated.

Because the frame number of the start-up portion of track is fewer, can not follow the tracks of in conjunction with the information of multiframe, therefore can adopt the tracking of the prior art it may occur to persons skilled in the art that to follow the tracks of start track.

Step 2: the coordinate that obtains each touch point of next frame.

In present embodiment, a frame that is associated, needs to be associated with each touch point in next frame with each touch point in former frame is called to present frame, a frame before present frame is former frame, a frame after present frame is a rear frame, and therefore, former frame, present frame and next frame are three frames continuous in carrying out touch recognition process, suppose that present frame is k frame, former frame is k-1 frame so, and next frame is k+1 frame, and k is more than or equal to 2.

Step 3: according to the optimum combination between acquisition of information present frame touch point, touch point and next frame touch point in continuous multiple frames, concrete grammar can be taked: according to continuously selecting the optimum combination between each touch point of present frame and each touch point of next frame the direction continuity of a frame and speed continuity, likely combining between each touch point of present frame and each touch point of next frame in identical strip path curve, a >=3 wherein, preferably, a=3, the a=3 of take in the present embodiment describes as example.

So-called direction continuity refers to the continuity of the direction of motion of different frame touch point in identical strip path curve, direction continuity is for characterizing the size that in identical strip path curve, different frame touch point direction of motion changes, preferably, direction continuity can be by touch point from k-1 frame the vectorial S to touch point in k frame _kwith the vectorial S of touch point from k frame to touch point in k+1 frame _k+1angle theta and direction weights omega ₁determine, as shown in Figure 5, for the continuous three frame touch point P on i bar track _i(k-1), P _iand P (k) _i(k+1), from P _i(k-1) to P _i(k) vector is S _k, from P _i(k) to P _i(k+1) vector is S _k+1, vectorial S _kwith S _k+1angle theta between vector represents the variation of touch point direction of motion.

So-called speed continuity refers to the continuity of the movement rate of touch point in identical strip path curve, speed continuity is for characterizing the size that in identical strip path curve, different frame touch point movement rate changes, preferably, the distance s to touch point in k frame by touch point from k-1 frame _kwith the distance s of touch point from k frame to touch point in k+1 frame _k+1and speed weights omega ₂determine, the frame per second of obtaining touch point due to general touch-screen is identical, every two frames between interlude identical, therefore the distance between available two frame touch points represents the movement velocity of touch point, in Fig. 5, touch point P on i bar track _iand P (k-1) _i(k) distance between is s _k, touch point P _iand P (k) _i(k+1) distance between is s _k+1.

Supposing has m touch point in k frame, in k+1 frame, have n touch point, in the situation that there is no track cross, a touch point in k frame/the k+1 frame is at most only associated with a touch point in k+1 frame/the k frame, if m≤n is total between each touch point in this two frame

plant combination, if m > is n, total between each touch point in this two frame

kind of combination, as shown in Figure 6, is that k frame and k+1 frame respectively have likely combined situation of institute in the situation of three touch points, and three touch points in k frame are respectively A _k, B _k, C _k, three touch points of k+1 frame are respectively A _k+1, B _k+1, C _k+1between three touch points in k frame and three touch points in k+1 frame, six kinds of (a), (b), (c), (d), (e), (f) shown in total figure may combine so, track following is selected a kind of optimum combination exactly from these six kinds may be combined, and association is carried out in a touch point in two frames of the front and back under optimum combination.

Due in most cases, to the touch operation of touch-screen, be all that user completes, exercise habit and limit of sports record due to user, in touch operation process, the variation of movement velocity and direction of motion is all continuous, therefore can not undergo mutation, can the direction continuity of touch objects and speed continuity likely combining between each touch point of k frame and each touch point of k+1 frame, obtain optimum combination the touch point in k frame is carried out associated with the touch point in k+1 frame one by one by considering.

Touch-surface for touch-screen exists in the situation of many tracks, in touch point in historical frames in correct track (each frame before present frame) and present frame, direction, the speed of corresponding touch point should be mated most, be that direction and velocity variations should meet rule (having minimum rate of change), for i bar track, can set up following departure function:

$d_i^k=f(p_i^{k-1},p_i^k,p_i^{k+1})$

The coherent function in path that can set up track based on above departure function, the value of the coherent function in path under may combining by more every kind is obtained optimum combination.

As shown in Figure 7, the concrete method of obtaining optimum combination is:

301: according to the direction continuity of continuous 3 frames in identical strip path curve and speed continuity, set up the coherent function in following path:

$f(p_i^{k-1},p_i^k,p_i^{k+1})={\mathrm{\ω}}_1(1-\cos \mathrm{\θ})+{\mathrm{\ω}}_2(1-2\frac{\sqrt{s_k{s}_{k+1}}}{s_k+s_{k+1}})={\mathrm{\ω}}_1(1-\frac{S_k\·S_{k+1}}{s_k{s}_{k+1}})+{\mathrm{\ω}}_2(1-2\frac{\sqrt{s_k{s}_{k+1}}}{s_k+s_{k+1}})$

Wherein, for i bar track, i=1,2 ..., n, n is the number of track in k frame, S _kfor the vector of touch point from k-1 frame to touch point in k frame, S _k+1for the vector of touch point from k frame to touch point in k+1 frame, θ is vectorial S _kwith vectorial S _k+1angle, ω ₁for direction weight, ω ₂for speed weight, and ω ₁+ ω ₂=1, s _kfor the distance of touch point from k-1 frame to touch point in k frame, s _k+1be in k frame touch point to the distance of touch point in k+1 frame.

Preferably, ω ₁=0.2 ~ 0.7, ω ₂=0.3 ~ 0.8, due to generally, the direction of touch objects changes specific rate and changes more flexibly, can make direction continuity occupy less weight, and speed continuity is occupied larger weight.

302: for each combination in likely combining, calculate the coherent functional value in path of every track, and calculate each track the coherent functional value in path and, for each combination, calculate each paths under every kind of combination deviation and:

the total number in the path that wherein N is current tracking.

303: in likely combining, choose described each track the coherent functional value in path and minimum a kind of as the optimum combination between each touch point of k frame and each touch point of k+1 frame, to the coherent functional value in the path of obtaining (deviation in path and) according to order sequence from small to large, select a minimum combination as the optimum combination between each touch point in two frames of front and back.

Step 4: association is carried out in the touch point between present frame (k frame) and next frame (k+1 frame) according to the array mode of the optimum combination of obtaining in step 3.

Step 5: output present frame (k frame) carries out the track after associated with each touch point of next frame (k+1 frame), also the corresponding touch point that before and after being about to, two frames are associated couples together and forms track output, record the coordinate of each touch point of next frame (k+1 frame), also can continuous associated multiframe export again the track being associated, the track of the two frame touch points that output is not associated immediately yet, first buffer memory is carried out in the two frame touch points that are associated, output trajectory again after associated multiframe.

Step 6: judge whether that new track adds, concrete determination methods is:

For k frame touch point, judge and in k+1 frame, whether have the not associated touch point not being associated with touch point in k frame, if exist, judge that whether this not associated touch point is successively at k+2 frame, associated in k+3 frame, judge successively that whether this not associated touch point is associated in k+2 frame, whether associated in k+3 frame with the touch point that in k+1 frame, this not associated touch point is associated in k+2 frame, if, the starting point that the not associated touch point in k+1 frame is new track, step 1 is returned to in this not associated touch point follows the tracks of, otherwise, this not associated touch point will be abandoned, enter step 7.As shown in Figure 8 a, in k+1 frame, have one not by the touch point D of former frame association _k+1, Continuous Tracking three frames, touch point D in k+1 frame _k+1by a touch point D in k+2 frame _k+2association, touch point D _k+2by a touch point D in k+3 frame _k+3association, therefore, can be by touch point D _k+1starting point for new track.And in Fig. 8 b, in k+1 frame, have one not by the touch point D of former frame association _k+1, but in two follow-up frames or multiframe, do not exist with k+1 frame in touch point D _k+1the touch point being associated, therefore, by touch point D _k+1as noise spot, abandon., all there is same touch objects in the method that judges whether to occur new track of this Continuous Tracking three frames, just think new track continuously in three frames, can prevent the noise spot occurring in a certain frame to be also identified as new track, can effectively remove noise.Certainly, also can judge whether to occur new track, the natural number that wherein t is greater than 1, preferably 2≤t≤5 by Continuous Tracking t frame.

Step 7: judged whether that track finishes, concrete determination methods is as follows:

For k frame touch point, judge and in k frame, whether have the touch point not being associated with touch point in k+1 frame, if, judge the later continuously number of the whether no more than k+1 frame of the number touch point of touch point in t frame of k+1 frame, if so, the not associated corresponding track in touch point finishes in k frame, otherwise, make the numerical value of k add 1, go to step 2, wherein 2≤t≤5.As shown in Fig. 9 a, in k frame, there are 3 touch points, k+1 frame has 2 touch points, touch point C in k frame _kfirst not associated with the touch point in k+1 frame, and in two follow-up frames, all only identify two touch points, same do not have and the C that is associated _ktouch point, therefore, judgement touch point C _kit is the end point of the 3rd track.And in Fig. 9 b, in k frame, there are 3 touch points, in k+1 frame, there are 2 touch points, in follow-up k+2 and k+3 frame, be all 3 touch points, only in k+1 frame, lacked individual touch point, this situation may be due to wrong in touch recognition process, true touch point to be removed as ghost point, or due to the uneven little broken string forming of exerting oneself in setting-out process, do not represent the end of track, therefore, in track tracing process, should continue to follow the tracks of this track, and should not be processed into track, not finish.This Continuous Tracking three frames or multiframe judge the method whether track finishes, and continuous three frames or multiframe are disconnected and be just identified as track and finish, and can prevent there is too much broken string in track following process, affect writing effect.

Present embodiment provides a kind of touch track tracking based on the function that links up according to the path of direction continuity and the foundation of speed continuity, direction variation and velocity variations due to continuous 3 frames in the front and back that consider, the in the situation that of can there is a plurality of touch point in every frame, obtain optimum tracking combination, there is good robustness, can greatly improve the writing effect of touch-screen, improve user's impression.

The second embodiment

Present embodiment provides another kind of touch track tracking, be with the touch track tracking difference in the first embodiment: except the front cross frame of track, whole track following process is not to adopt a kind of method to follow the tracks of, concrete, front q (q >=2) frame can adopt the capable track following of minimum Eustachian distance matching method described in step 1, the center section of track adopts step 2 to the method described in step 5 to carry out track following, and last M (M >=1) frame adopts the method for the Euclidean distance minimum described in step 1 to carry out track following again; Or front N (N >=3) frame of track can adopt the minimum Eustachian distance matching method described in step 1 to carry out track following, and each later frame all adopts step 2 to the method described in step 7 to carry out track following.That is to say, can be only the one to multiple frame in the centre of track be adopted to the method for the coherent function in path of setting up according to direction continuity and speed continuity described in the first embodiment, follow the tracks of, and each frame to two ends adopts the trace tracking method of prior art to follow the tracks of.

Obviously, those skilled in the art can carry out various changes and modification and not depart from the spirit and scope of the present invention the present invention, situation about being associated with a plurality of touch points in k+1 frame/the k frame as comprised touch point in k frame/the k+1 frame in the array mode likely combining; Also can choose the optimum combination between each touch point of k frame and each touch point of k+1 frame according to the size of average, mean square value or the root-mean-square value of the coherent functional value in path, in likely combining a kind of combination of average, mean square value or the root-mean-square value minimum of the coherent functional value of path selection as optimum combination, if within these modifications of the present invention and modification belong to the scope of the claims in the present invention and equivalent technology thereof, the present invention is also intended to comprise these changes and modification.

Claims (11)

1. a touch track tracking, is characterized in that, comprises the following steps:

A, by comprising present frame, in interior front q frame, carry out association in each touch point successively, and the coordinate of each touch point of q frame before record, wherein q >=2;

B, obtain the coordinate of each touch point of next frame;

C, according to the information of continuous multiple frames touch point, obtain the optimum combination between each touch point of present frame and each touch point of next frame;

D, according to the array mode in described optimum combination, each touch point of present frame is carried out associated with each touch point of next frame;

Track after E, output present frame and each touch point of next frame are associated, records the coordinate of each touch point of next frame;

F, return to step B.

2. touch track tracking according to claim 1, is characterized in that, described in obtain the optimum combination between each touch point of present frame and each touch point of next frame method be specially:

According to continuously selecting the optimum combination between each touch point of present frame and each touch point of next frame the direction continuity of a frame and speed continuity, likely combining between each touch point of present frame and each touch point of next frame in identical strip path curve, a >=3 wherein.

3. touch track tracking according to claim 2, it is characterized in that, note present frame is k frame, each execution of step E, the numerical value of k adds 1, for described each combination in likely combining, a touch point in k frame/the k+1 frame is at most only associated with a touch point in k+1 frame/the k frame, wherein k >=2.

4. touch track tracking according to claim 3, is characterized in that a=3.

5. touch track tracking according to claim 4, is characterized in that, in step C, and the vectorial S by touch point from k-1 frame to touch point in k frame _kwith the vectorial S of touch point from k frame to touch point in k+1 frame _k+1angle theta and direction weights omega ₁determine described direction continuity; And/or by touch point from k-1 frame the distance s to touch point in k frame _kwith the distance s of touch point from k frame to touch point in k+1 frame _k+1and speed weights omega ₂determine described speed continuity.

6. touch track tracking according to claim 5, is characterized in that, the method for obtaining the optimum combination between each touch point of k frame and each touch point of k+1 frame in step C is specially:

B1, according to the described direction continuity of continuous 3 frames in identical strip path curve and described speed continuity, set up the coherent function in following path:

$f(p_i^{k-1},p_i^k,p_i^{k+1})={\mathrm{\ω}}_1(1-\cos \mathrm{\θ})+{\mathrm{\ω}}_2(1-2\frac{\sqrt{s_k{s}_{k+1}}}{s_k+s_{k+1}})={\mathrm{\ω}}_1(1-\frac{S_k\·S_{k+1}}{s_k{s}_{k+1}})+{\mathrm{\ω}}_2(1-2\frac{\sqrt{s_k{s}_{k+1}}}{s_k+s_{k+1}})$

Wherein, for i bar track, i=1,2 ..., n, n is the number of track in k frame, S _kfor the vector of touch point from k-1 frame to touch point in k frame, S _k+1for the vector of touch point from k frame to touch point in k+1 frame, θ is vectorial S _kwith vectorial S _k+1angle, ω ₁for direction weight, ω ₂for speed weight, and ω ₁+ ω ₂=1, s _kfor the distance of touch point from k-1 frame to touch point in k frame, s _k+1be in k frame touch point to the distance of touch point in k+1 frame;

B2, for described each combination in likely combining, calculate the coherent functional value in path of every track, and calculate each track the coherent functional value in path and;

B3, the described coherent functional value in path of choosing described each track in likely combining and minimum a kind of as the optimum combination between each touch point of k frame and each touch point of k+1 frame.

7. touch track tracking according to claim 6, is characterized in that, the coherent functional value in described path and by average, mean square value or the root-mean-square value of the coherent functional value in path, replaced.

8. touch track tracking according to claim 6, is characterized in that ω ₁span be 0.2 to 0.7, ω ₂span be 0.3 to 0.8.

9. according to the touch track tracking described in any one in claim 3 to 8, it is characterized in that, after step e, also comprise the step that judges whether that new track adds, concrete grammar is:

For k frame touch point, judge and in k+1 frame, whether have the not associated touch point not being associated with touch point in k frame, if exist, judge this not associated touch point whether successively k+2 frame ..., associated in k+t frame, the starting point that if so, the not associated touch point in k+1 frame is new track, this corresponding track in not associated touch point is followed the tracks of, otherwise, abandon this not associated touch point, wherein 2≤t≤5.

10. according to the touch track tracking described in any one in claim 3 to 8, it is characterized in that, after step e, also comprise the step that judges whether that track finishes, concrete grammar is:

For k frame touch point, judge and in k frame, whether have the touch point not being associated with touch point in k+1 frame, if, Continuous Tracking t frame, judges the later continuously number of the whether no more than k+1 frame of the number touch point of touch point in t frame of k+1 frame, if, in k frame, the not associated corresponding track in touch point finishes, otherwise, return to step B and proceed to follow the tracks of, wherein 2≤t≤5.

11. according to the touch track tracking described in any one in claim 1 to 8, it is characterized in that q=2 adopts with the following method association is carried out in the touch point between the front cross frame of track:

Obtain in the first frame the coordinate of each touch point in each touch point and the second frame;

In each touch point of the second frame, in search and the first frame, the touch point of first touch point Euclidean distance minimum, carries out association by these two touch points;

In the not associated touch point of the second frame, in search and the first frame, the touch point of not associated touch point Euclidean distance minimum, carries out association by these two touch points;

Judge that whether the touch point in the first frame or the second frame is all associated, if so, next frame touch point is followed the tracks of, if not, return to previous step.

Images