TW201421298A - Method for correcting touch position - Google Patents

Abstract

A method for correcting a touch position, for using an electronic apparatus, is provided. The method includes: receiving a current touch event; obtaining a prediction information based on a correction information of a previous touch event which is received at a previous time point before the current touch event; obtaining a correction information of the current touch event based according to the prediction information and a measurement position of the current touch event; and updating a position of the current touch event in a display unit by using the correction information of the current touch event.

Description

Correct the method of touching the position

This case is about a touch technique, and in particular, a method for correcting the touch position.

In recent years, with the advancement of touch technology and the rapid development of various applications of electronic products, touch panels have become very popular. The touch panel allows the user to click directly on the screen and act according to the selected location. For example, the cursor moves as the user slides, drags, etc. on the touch panel. However, due to the measurement error of the system, the uneven speed of the human sliding, or the slight tremor of the hand, the problem of frame jitter is caused.

In order to solve the problem of picture jitter, it is generally corrected by a linear regression algorithm, interpolation or extrapolation. The linear regression algorithm needs to collect information about a large number of touch events, and the more the amount of related information, the smoother the corrected touch operation displayed on the screen. However, as the amount of data increases, the calculation time will also become longer and the reaction time will be slower. In addition, interpolation or extrapolation cannot perform optimization for slow sliding, so there is still image jitter during slow sliding. problem.

This case provides a way to correct the touch position, which can quickly correct the touch position to solve the picture jitter problem.

The method of correcting the touch position of the present case is for an electronic device. The method includes: receiving a current touch event; obtaining prediction information of the current touch event based on the correction information of the previous touch event received at a previous time point of the current touch event; and based on the predicted information and the current touch event The measurement position, the correction information of the current touch event is obtained; and the correction information of the current touch event is used to update the position of the current touch event in the display unit.

In an embodiment of the present invention, the correction information includes a correction position and a correction deviation, and the prediction information includes a predicted position and a predicted deviation. The step of obtaining the prediction information of the current touch event time point based on the correction information of the previous touch event received at the previous time point of the current touch event includes: the corrected position of the previous touch event, as The predicted position of the current touch event time point; and the corrected deviation of the previous touch event plus the value of the predicted deviation value as the predicted deviation of the current touch event.

In an embodiment of the present invention, the step of obtaining the correction information of the current touch event according to the predicted information and the measurement position of the current touch event comprises: calculating the current touch based on the predicted deviation and the measured deviation value of the current touch event The gain value of the event; based on the gain value and the predicted position of the current touch event, obtaining the corrected position of the current touch event; and obtaining the predicted deviation based on the gain value and the current touch event Corrected the deviation of the current touch event.

In an embodiment of the present invention, the gain value is obtained by dividing the predicted deviation of the current touch event by the predicted deviation of the current touch event plus the value after the measurement deviation value. The corrected position of the current touch event is obtained by subtracting the predicted position of the current touch event from the measured position of the current touch event and multiplying the value obtained by the gain value, plus the predicted position of the current touch event. The value obtained by subtracting the gain value is multiplied by the predicted deviation of the current touch event, thereby obtaining the corrected deviation of the current touch event.

In an embodiment of the present invention, after obtaining the correction information of the current touch event, the amount of displacement between the corrected position of the current touch event and the corrected position of the previous touch event may also be calculated. And, the measurement deviation value is adjusted according to the displacement amount. For example, when the displacement amount is greater than a threshold value, the predicted deviation value is increased; when the displacement amount is less than the threshold value, the measurement deviation value is decreased. Or, according to the preset range in which the displacement amount is located, the measurement deviation value is adjusted according to the adjustment value corresponding to the preset range. In addition, the predicted deviation value can be adjusted according to the displacement amount.

In an embodiment of the present invention, when the current touch event is the initially received touch event, the measured position of the current touch event is used as the predicted position of the current touch event.

In an embodiment of the present invention, after obtaining the correction information of the current touch event, the correction information of the current touch event is recorded to the storage unit, and the correction information of the previous touch event is deleted.

In order to make the above features and advantages of the present invention more comprehensible, the following embodiments are described in detail with reference to the accompanying drawings.

100‧‧‧Electronic devices

110‧‧‧Processing unit

120‧‧‧Touch unit

130‧‧‧Display unit

140‧‧‧ storage unit

S205~S220‧‧‧Steps to correct the method of touching the position

S305~S310‧‧‧Other steps to correct the touch position

1 is a block diagram of an electronic device in accordance with an embodiment of the present invention.

2 is a flow chart of a method of correcting a touch position in accordance with an embodiment of the present invention.

3 is a flow chart of a variation of the method of correcting a touch position in accordance with an embodiment of the present invention.

4 is a schematic diagram of position displacement amounts before and after modification in accordance with an embodiment of the present invention.

1 is a block diagram of an electronic device in accordance with an embodiment of the present invention. Referring to FIG. 1 , the electronic device 100 includes a processing unit 110 , a touch unit 120 , a display unit 130 , and a storage unit 140 . The processing unit 110 is coupled to the touch unit 120, the display unit 130, and the storage unit 140. The electronic device 100 is, for example, a mobile phone, a smart phone, a tablet computer, a notebook computer, a desktop computer, a car computer, a navigation device, or the like.

Here, the processing unit 110 is, for example, a central processing unit (CPU). The touch unit 120 is, for example, a capacitive touch panel or a group touch panel. The display unit 130 is, for example, a liquid crystal display (LCD) or a plasma display panel (Plasma Display Panel, PDP). The storage unit 140 is, for example, a random access memory (RAM).

In this embodiment, the image processing operation is processed by the graphics processing unit. However, in other embodiments, the electronic device 100 may also be provided with a separate graphics card or graphics processing unit or processing unit 110 to specifically handle image processing operations. In addition, in other embodiments, the touch unit 120 can also be integrated with the display unit 130 to touch the display unit (such as a touch screen); the electronic device 100 can also be provided with a bridge control unit (such as a south bridge chip, a north bridge chip, etc.) The processing unit 110 is coupled to the touch unit 120, the display unit 130, the storage unit 140, and other peripheral devices through the bridge control unit.

The steps of the method for correcting the touch position are explained below with the electronic device 100 described above. 2 is a flow chart of a method of correcting a touch position in accordance with an embodiment of the present invention. Referring to FIG. 1 and FIG. 2 simultaneously, in step S205, the processing unit 110 receives the current touch event via the touch unit 120. For example, the user can perform a touch operation in the touch unit 120, and the touch unit 120 can capture the touch event corresponding to the touch operation at different time points, for example, and transmit the touch event to the processing unit 110.

Next, the processing unit 110 uses the correction information after the position correction of the previous touch event at the previous time point to predict the position of the current touch event received at the current time point. That is, as shown in step S210, the processing unit 110 obtains prediction information of the current touch event based on the correction information of the previous touch event received at the previous time point of the current touch event. That is to say, assuming that the current time point is t, the processing unit 110 calculates the time point t by using the correction information of the touch event (herein referred to as "previous touch event") of the previous time point t-1. Touch event This is the prediction information called "current touch event".

Then, the processing unit 110 further corrects the actual measurement position of the current touch event according to the predicted result. As shown in step S215, the processing unit 110 obtains the correction information of the current touch event according to the predicted information and the measurement position of the current touch event.

The Kalman filter is taken as an example below. Moreover, the correction information includes a correction position and a correction deviation, and the prediction information includes a predicted position and a predicted deviation. In step S210, the corrected position of the previous touch event (represented by x _{t -1| t -1 at the} bottom) is used as the predicted position of the current touch event (hereinafter represented by x _{t | t -1} ). Moreover, the correction deviation of the previous touch event (represented by p _{t -1| t -1 at the} bottom) plus the value of the predicted deviation value (represented by q underneath) is used as the predicted deviation of the current touch event (bottom p _{t | t -1} stands for). According to this, the following formula (1) and formula (2) can be obtained.

x _{t | t -1} = x _{t -1| t -1} (1)

p _{t | t -1} = p _{t -1| t -1} + q (2)

In step S215, the processing unit 110 calculates the gain value of the current touch event (represented by K _t under the basis) based on the predicted deviation of the current touch event and the measured deviation value (represented by r); and, based on the gain value The predicted position of the current touch event (represented by z _t below), the corrected position of the current touch event (represented by x _{t | t} ); in addition, based on the predicted deviation of the gain value from the current touch event, the current Corrected deviation of the touch event (represented by p _{t | t} ).

Specifically, the current touch event anticipations p _{t | t -1,} divided by the current touch event anticipations p _{t | t -1} plus the measured value after the offset value r, namely p _{t | t - 1} /( p _{t | t -1} +r), whereby the gain value K _{t is obtained} . The value obtained by multiplying the predicted position x _{t | t -1 of the} current touch event by the gain value K _t is added to the measurement position z _{t of the} current touch event, plus the predicted position of the current touch event x _{t | t -1 to} obtain the corrected position x _{t | t of the} current touch event. The value after subtracting the gain value K _t is multiplied by the predicted deviation p _{t | t -1 of the} current touch event, thereby obtaining the corrected deviation p _{t | t of the} current touch event. That is, (1- K _t ) represents the weight of the prediction bias p _{t | t -1} of the current touch event. According to this, the following formula (3) to formula (5) can be obtained.

K _t = p _{t | t -1} ( p _{t | t -1} + r ) ^-1 (3)

x _{t | t} = x _{t | t -1} + K _t ( z _t - x _{t | t -1} ) (4)

p _{t | t} =(1- K _t ) p _{t | t -1} (5)

The above equations (1) and (2) are used to predict the position. In the formula (1), when the current touch event is the initial touch event, that is, in the case of no previous touch event, the current touch event is taken as the current touch. The predicted location of the event. The above equation (3) to equation (5) are used to correct the position. Each calculation is updated with the updated gain value K _t to obtain the best correction result. And the correction deviation p _{t | t of the} best correction result is supplied to the next recursive operation.

The gain value K _t is used to measure the reliability of the predicted position x _{t | t -1} of the current touch event and the measurement position z _t of the current touch event. The larger the gain value K _t , represents the measurement position z _t The higher the reliability, the smaller the gain value K _t , and the higher the reliability of the predicted position x _{t | t -1} representing the current touch event. Accordingly, the gain value K _{t is} used to adjust the correction range of the current touch event.

If the touch operation is maintained at the constant speed operation, the gain value K _t will approach a value. Since the deviation between the predicted position and the measured position does not change, the gain value K _t approaches a value until it finally converges to a value and does not change.

After the correction information of the current touch event is obtained, in step S220, the position of the current touch event in the display unit 130 is updated with the correction information of the current touch event. That is, after calculating the correction information of the current touch event, the processing unit 110 transmits the correction information (eg, the corrected position) to the graphics processing driver or the graphics processor for drawing, and then presented in the display unit 130.

In addition, FIG. 3 is a flowchart of a modification of the method of correcting the touch position according to an embodiment of the present invention. In FIG. 3, the same steps as those of FIG. 2 are denoted by the same reference numerals, and the related description is omitted here.

After obtaining the correction information of the current touch event, in addition to transmitting the correction information of the current touch event to the graphics processing driver or the graphics processor for drawing, the processing unit 110 may further perform the processing as shown in step S305. The amount of displacement between the corrected position of the current touch event and the corrected position of the previous touch event is calculated. Next, in step S310, the measured deviation value is adjusted in accordance with the displacement amount described above. After that, the original measurement deviation value is overwritten with the adjusted measurement deviation value, and is used by the touch event at the next time point.

Specifically, when the fast-slip operation is performed, the reliability of the measurement position of the current touch event is high, and the measurement deviation value can be reduced at this time. That is to say, the larger the displacement amount, the faster the moving speed, indicating that the predicted position is less accurate, so the weight of the measurement position is higher (ie, the gain value K _t is larger). Accordingly, the measurement deviation value is reduced to improve the problem that the picture cannot keep up.

In addition, when the slow-slip operation is performed, the reliability of the predicted position of the current touch event is high, and the measurement deviation value can be increased at this time. That is to say, the smaller the displacement amount, the slower the moving speed, indicating that the predicted position is more accurate, so the weight of the predicted position is higher (ie, the smaller the gain value K _t ). Accordingly, the measurement deviation value is increased to improve the problem of picture shake.

For example, a threshold value can be set as a basis for judging the fast-slip operation and the slow-slip operation. Therefore, when the displacement amount is greater than a threshold value, the predicted deviation value is increased. When the displacement amount is less than the above threshold value, the measurement deviation value is adjusted to be small. However, the above is only a simple implementation manner. In practice, the resolution of the display unit 130 and the influence of other peripheral devices are also taken into consideration, and thus a plurality of sets of preset ranges are set, thereby serving as a basis for judging the sliding speed. Accordingly, according to the preset range in which the displacement amount is located, the measurement deviation value is adjusted according to the adjustment value corresponding to the preset range.

For example, if the resolution of the display unit 110 is 1920×1200, three sets of preset ranges, namely “1~16”, “16~32” and “32 or more”, are set in advance in the electronic device 100. The corresponding adjustment values are 0.1, 0.5, and 1. Assuming that the displacement amount is 10, that is, in the preset range "1~16", the measurement deviation value is adjusted to 0.1. Or, if the displacement amount is 35, the measurement deviation value is adjusted to 1. In addition, it is also possible to determine which value of the measurement deviation value is to be adjusted to 0 to 0.1, 0.1 to 0.5, and 0.5 to 1 according to a function.

In addition, the processing unit 110 can also adjust the predicted deviation value according to the displacement amount. Alternatively, the predicted deviation value and the measured deviation value are appropriately adjusted depending on the displacement amount. That is, whether the measurement deviation value or the prediction deviation value is adjusted, the gain value K _{t is} changed accordingly, thereby affecting the result of the current touch event correction. Therefore, depending on the situation, it is decided to adjust only the predicted deviation value or the measurement deviation value, or to adjust the prediction deviation value and the measurement deviation value at the same time.

4 is a schematic diagram of position displacement amounts before and after modification in accordance with an embodiment of the present invention. Please refer to FIG. 4 and the following Table 1A and Table 1B. In the present embodiment, the description will be made only with the displacement amount of the X coordinate. The bottom table 1A and the table 1B are for convenience of explanation, and only the 17 time points in FIG. 4 are listed.

With respect to the pre-corrected displacement amount at time point A (85 msec), time point B (102 msec), and time point C (136 msec) of Fig. 4, the displacement amount at time point A is 22.68, but to time point B. Dropped to 10.57, the displacement at time C increases to 24.54. That is to say, the displacement amount from the time point A to the time point B is drastically decreased, and in the case where the displacement amount from the time point B to the time point C is sharply increased, the screen movement is slowed down (time point A to time point B). It also becomes fast immediately (time point B to C), thus causing a phenomenon of frame jitter on the screen.

After the correction, the displacement amount at each time point from time point A to time point C is relatively close, that is, the maximum displacement amount difference between time point A and time point C is changed from 13.97 (24.54-10.57). 5.42 (17.90-12.48). The closer the amount of displacement is, the smoother the picture will move, thus improving the picture jitter.

In addition, with respect to the pre-correction displacement amount at the time point D (170 msec), the time point E (204 msec), and the time point F (221 msec) of FIG. 4, the displacement amount at the time point D is 12.81, to the time. The displacement of point E becomes 26.71, and the time point F drops to 13.21. The displacement from time point D to time point E increases sharply, and the displacement from time point E to time point F suddenly decreases sharply, causing the screen to move faster (time point D to time point E) to become slow again (time) Point E to time point F), thus causing a phenomenon in which the picture is shaken.

After the correction, the displacement of each time point from time point D to time point F will be relatively close, and the maximum displacement difference between time point D and time point F will change from 13.9 (26.71-12.81) to 5.38 ( 19.62-14.24), thus improving the picture jitter.

In addition, after obtaining the correction information of the current touch event, the processing unit 110 deletes the correction information of the current touch event to the storage unit 140, and deletes the correction information of the previous touch event recorded by the storage unit 140. Only the predicted deviation value q, the measured deviation value r, and the gain value K _{t of the} current time point _t , the corrected position x _{t | t,} and the corrected deviation p _{t | t} may be stored in the storage unit 140.

Although the above embodiment uses the X coordinate as an example, the calculation of the Y coordinate can also be the same as the flow of the above embodiment, and the X coordinate and the Y coordinate can also be calculated at the same time. There is no limit here.

In summary, this case only uses the previous touch event received at the previous time point to correct the current touch event received at the current time point, and uses the displacement calculation to improve the reaction time of the nonlinear motion, which can be used at the operation speed. Improve the problem of picture jitter with fast and saving storage space.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present case. Any person having ordinary knowledge in the technical field can protect the case without making any changes or refinements without departing from the spirit and scope of the present case. The scope is subject to the definition of the scope of the patent application.

S205~S220‧‧‧Steps to correct the method of touching the position

Claims (12)

A method for correcting a touch position for an electronic device, the method comprising: receiving a current touch event; and based on a correction information of a previous touch event received at a previous time point of the current touch event, Obtaining a prediction information of the current touch event; obtaining the correction information of the current touch event according to the predicted information and a measurement position of the current touch event; and updating the correction information of the current touch event The current touch event is in a position in a display unit. The method of claim 1, wherein the correction information includes a corrected position and a corrected deviation, the predicted information including a predicted position and a predicted deviation, wherein the predicted time is based on a previous time of the current touch event The step of obtaining the predicted information of the current touch event by the received correction information of the previous touch event includes: using the corrected position of the previous touch event as the prediction of the current touch event a position; and the corrected deviation of the previous touch event plus a value of the predicted deviation value as the predicted deviation of the current touch event. The method of claim 2, wherein the step of obtaining the correction information of the current touch event according to the predicted information and the measurement position of the current touch event comprises: the current touch event based on the current touch event Predicting the deviation and a measured deviation value, calculating the a gain value of the current touch event; obtaining the corrected position of the current touch event based on the gain value and the predicted position of the current touch event; and the predicted deviation from the current touch event based on the gain value , obtaining the correction deviation of the current touch event. The method of claim 3, wherein the calculating the gain value of the current touch event comprises: dividing the predicted deviation of the current touch event by the predicted deviation of the current touch event plus The value after the deviation value is measured, thereby obtaining the gain value. The method of claim 3, wherein the obtaining the corrected position of the current touch event comprises: subtracting the predicted position of the current touch event from the measured position of the current touch event, and then multiplying the predicted position of the current touch event The value obtained by the gain value is added to the predicted position of the current touch event to obtain the corrected position of the current touch event. The method of claim 3, wherein the step of obtaining the correction deviation of the current touch event comprises: multiplying the value obtained by subtracting the gain value by 1 from the predicted deviation of the current touch event, This obtains the correction deviation of the current touch event. The method of claim 3, wherein after the step of obtaining the correction information of the current touch event according to the predicted information and the measurement position of the current touch event, the method further comprises: calculating the current touch The corrected position of the touch event and the repair of the previous touch event The amount of displacement between the positive positions; and adjusting the measured deviation value according to the amount of displacement. The method of claim 7, wherein the step of adjusting the measured deviation value according to the displacement amount comprises: when the displacement amount is greater than a threshold value, increasing the predicted deviation value; and when the displacement amount When the threshold value is less than this threshold value, the measurement deviation value is reduced. The method of claim 7, wherein the step of adjusting the measured deviation value according to the displacement amount comprises: according to a preset range in which the displacement amount is located, according to the adjustment value corresponding to the preset range Adjust the measurement deviation value. The method of claim 3, wherein after the step of obtaining the correction information of the current touch event according to the predicted information and the measurement position of the current touch event, the method further comprises: calculating the current touch a displacement amount between the corrected position of the collision event and the corrected position of the previous touch event; and adjusting the predicted deviation value according to the displacement amount. The method of claim 2, wherein when the current touch event is an initially received touch event, the measured position of the current touch event is the predicted position of the current touch event. The method of claim 1, wherein after the step of obtaining the correction information of the current touch event, the method further comprises: recording the correction information of the current touch event to a storage unit; and deleting the front This correction information for the second touch event.