TW201445359A - Handheld pointer device and tilt angle adjustment method thereof - Google Patents

Abstract

An exemplary embodiment of the present disclosure provides a pointer device and a tilt angle adjustment method thereof. The tilt angle adjustment method includes the following steps. Images corresponding to the position of a reference point are captured as the pointer device pointing toward the reference point to generate a plurality of frames. Whether the reference point has substantially moved is subsequently determined based on the plurality of frames. When determines that the reference point has not substantially moved, causes an accelerometer unit of the pointer device to detect accelerations thereof over various axes so as to update a first tilt angle being used currently to a second tilt angle, accordingly. The pointer device may thus accurately and efficiently calculate the position of the reference point with the appropriate tilt angle of the pointer device used.

Description

Hand-held pointing device and tilt angle correction method thereof

The present invention relates to a pointing device and a method of correcting the same, and more particularly to a hand-held pointing device and a tilt angle correcting method thereof.

The handheld pointing device calculates the pointing point coordinate of the handheld pointing device by analyzing the position of the reference point in the sensed image area, and transmits the pointing point coordinate to the game host to perform related game operations, which has been Widely used in a variety of interactive remote control games, such as light gun games, baseball games and tennis games.

It is known that the distance between the image sensor on the handheld pointing device and the display screen and the angle of rotation when the image is captured may affect the calculation of the pointing point coordinates. Therefore, if the hand-held pointing device is not equipped with a device for detecting the tilt angle, when the image sensor of the hand-held pointing device is tilted, the hand-held pointing device cannot accurately determine the hand-held pointing device and the reference point. Misjudgment occurs between relative movements.

At present, the industry mainly uses two or more reference points or simultaneously adds an accelerometer and a gyroscope on the hand-held pointing device as a basis for judging the tilt angle of the image sensor on the device to solve the misalignment caused by the tilt. The problem. However, the use of more than two reference points, in addition to increasing the complexity of the positional calculation of the handheld pointing device, the image sensor on the handheld pointing device must also have a viewing angle that can sense more than two reference point position ranges. The use of accelerometers and gyroscopes, in addition to increasing the manufacturing cost of handheld pointing devices, also increases the energy consumption of handheld pointing devices.

In view of this, the embodiment of the present invention provides a hand-held pointing device and a tilt angle correcting method thereof, which can improve the accuracy of the reference point calculation positioning by actively correcting the tilt angle of the hand-held pointing device.

Embodiments of the present invention provide a tilt angle correction method for a hand-held pointing device, the method comprising the following steps. First, when the handheld pointing device points to a reference point, an image corresponding to the position of the reference point is captured, and a plurality of image frames are sequentially generated. Secondly, it is determined according to the image frames whether the reference point moves greatly. If it is determined that the reference point does not move substantially, the acceleration unit of the handheld pointing device senses the plurality of acceleration values of the handheld pointing device in the plurality of axial directions to calculate and update the current use of the handheld pointing device according to the acceleration values. The first tilt angle is a second tilt angle.

The embodiment of the invention further provides a tilt angle correction method for the handheld pointing device, the method comprising the following steps. First, when the handheld pointing device points to a reference point, an image corresponding to the position of the reference point is captured, and a plurality of image frames are sequentially generated. Secondly, based on any three consecutive image frames in the image frames, an acceleration change value of the reference point at the imaging position of the continuous image frames is calculated. Next, it is judged whether or not the acceleration change value is equal to zero. Then, if the acceleration change value is equal to zero, the acceleration unit of the handheld pointing device senses a plurality of acceleration values of the handheld pointing device in multiple axes to calculate and update the current use of the handheld pointing device according to the acceleration values. An angle of inclination is a second angle of inclination.

Embodiments of the present invention provide a handheld pointing device that includes an image capturing unit, an acceleration unit, and a processing unit. The image capturing unit is configured to capture an image corresponding to a reference point position, and sequentially generate a plurality of image frames. The acceleration unit is configured to sense a plurality of acceleration values of the handheld pointing device in multiple axes and generate an acceleration vector. The processing unit is coupled to the image capturing unit and the acceleration unit. The processing unit determines whether the reference point moves substantially according to the image frames. When the processing unit determines that the reference point has not moved significantly, the processing unit reads the acceleration unit to sense the acceleration values generated by the handheld pointing device on the multi-axis, according to the accelerations. The value calculates and updates the first tilt angle currently used by the handheld pointing device as the second tilt angle.

Embodiments of the present invention provide a handheld pointing device that includes an image capturing unit, an acceleration unit, and a processing unit. The image capturing unit is configured to capture an image corresponding to a reference point position, and sequentially generate a plurality of image frames. The acceleration unit is configured to sense a plurality of acceleration values of the handheld pointing device in multiple axes and generate an acceleration vector. The processing unit is coupled to the image capturing unit and the acceleration unit. The processing unit calculates an acceleration change value of the reference point at the imaging position of the continuous image frames according to any three consecutive image frames in the image frames. When the processing unit determines that the acceleration change value is zero, the processing unit determines that the read acceleration unit senses the acceleration values generated by the handheld pointing device in multiple axes to calculate and update the current use of the handheld pointing device according to the acceleration values. The first tilt angle is the second tilt angle.

In summary, the embodiment of the present invention provides a hand-held pointing device and a tilt angle correcting method thereof. The hand-held pointing device and the tilt angle correcting method thereof can determine whether to correct the tilt of the hand-held pointing device by analyzing whether the reference point is displaced. angle. The hand-held pointing device can actively determine whether the reference point moves substantially in an instant by calculating and analyzing the speed change of the reference frame in the image frame, the acceleration change of the reference point, and the acceleration change of the hand-held pointing device. Therefore, the hand-held pointing device of the present invention can effectively and accurately calculate the position of the reference point without adding a gyroscope or using two reference points, thereby simplifying the hardware structure and computational complexity of the hand-held pointing device. Reduce the design and manufacturing cost of the handheld pointing device.

The detailed description of the present invention and the accompanying drawings are to be understood by the claims The scope is subject to any restrictions.

10‧‧‧Handheld pointing device

11‧‧‧Image capture unit

13‧‧‧Acceleration unit

15‧‧‧Processing unit

17‧‧‧Transmission unit

20‧‧‧Host

21‧‧‧ Reference point

30‧‧‧Image display device

31‧‧‧ cursor

61, 61', 61" ‧ ‧ reference point image

S301~S309‧‧‧Step procedure

S401~S407‧‧‧Step procedure

S501~S511‧‧‧Step procedure

S701~S707‧‧‧Step procedure

S801~S823‧‧‧Step process

S901~S911‧‧‧Step procedure

, , ‧‧‧Location vector of reference point image

(x1, y1), (x2, y2), (x3, y3) ‧ ‧ coordinates of the reference point image

F1, f2, f3‧‧‧ image frame

X, Y, Z‧‧‧ image frame acquisition time

FIG. 1 is a diagram of a handheld pointing device applied to an interaction system according to an embodiment of the present invention. Schematic diagram of the system.

2 is a functional block diagram of a handheld pointing device according to an embodiment of the invention.

FIG. 3 is a schematic flow chart of a method for correcting a tilt angle of a hand-held pointing device according to an embodiment of the invention.

4 is a schematic flow chart of a method for judging a reference point displacement of a hand-held pointing device according to an embodiment of the present invention.

FIG. 5 is a schematic flow chart of a method for judging a reference point displacement of a hand-held pointing device according to another embodiment of the present invention.

6A-6C are schematic diagrams of image frames sensed when the handheld pointing device is moved according to an embodiment of the invention.

FIG. 7 is a schematic flow chart of a method for judging a reference point displacement of a hand-held pointing device according to another embodiment of the present invention.

FIG. 8 is a schematic flow chart of a method for correcting a tilt angle of a hand-held pointing device according to another embodiment of the present invention.

FIG. 9 is a schematic flow chart of a method for correcting a tilt angle of a hand-held pointing device according to still another embodiment of the present invention.

In the following, the invention will be described in detail by way of illustration of various exemplary embodiments of the invention. However, the inventive concept may be embodied in many different forms and should not be construed as being limited to the illustrative embodiments set forth herein. In addition, the same reference numerals may be used in the drawings to represent similar elements.

[Embodiment of Handheld Pointing Device]

The hand-held pointing device can be applied to a pointing point positioning of an image display device (not shown). Please refer to FIG. 1 . FIG. 1 is a schematic diagram of a handheld pointing device according to an embodiment of the present invention applied to an interactive system. The interactive system includes a handheld pointing device 10, a host 20, and an image display device 30. The host 20 is configured to read and execute a software program, such as a game software, and display the execution status of the software program. Like the display device 30, for the user to browse and control. The host 20 further provides a reference point 21 for the handheld pointing device 10 to capture an image as a basis for controlling the image display device 30 to display the cursor 31.

It should be noted that, in this embodiment, the host 20 can be, for example, a game console or a computer host. The image display device 30 can be, for example, but not limited to, a projection display device, a game console display screen, a television screen, and a computer display screen. The above game software can be stored in a CD, a flash drive or other equivalent memory device. The reference point 21 can be realized by a plurality of light-emitting diodes having a specific wavelength, such as an infrared light-emitting diode (IR LED), a laser diode or an ultraviolet light-emitting diode, arranged in reference points of various shapes. In addition, the light-emitting diodes may be electrically connected to the host 20 for obtaining power required for illumination, or may be supplied by an independent power source to supply power for illumination. In this embodiment, only one reference point is used, but the number of reference points 21 can be set by the general knowledge in the field of the invention, for example, one, two or plural. That is, FIG. 1 is only for explaining the operation of the handheld pointing device 10, and is not intended to limit the present invention.

Briefly, the hand-held pointing device 10 determines whether to update the tilt angle currently used by the hand-held pointing device 10, that is, the angle of rotation of the hand-held pointing device 10, by capturing the image of the reference point 21. The hand-held pointing device 10 accurately calculates the relative movement information between the hand-held pointing device 10 and the reference point 21 based on the positional information of the reference point 21 and the rotational angle currently used by the hand-held pointing device 10. The handheld pointing device 10 will calculate the relative movement information between the handheld pointing device 10 and the reference point 21 and transmit it to the host computer 20 via the wireless transmission mode to cooperate with the manipulation cursor 31 to perform the software program. Accordingly, the handheld pointing device 10 can selectively update or maintain the rotational angle of use of the handheld pointing device 10 to calculate the position of the reference point 21 to accurately calculate the relative movement information between the handheld pointing device 10 and the reference point 21. .

Furthermore, the hand-held pointing device 10 captures the image of the reference point 21 and sequentially generates a plurality of images with reference points 21 when pointing to the position of the reference point 21. Image frame. Then, the handheld pointing device 10 determines whether the reference point 21 is greatly moved at the imaging positions of the image frames according to the image frames to determine whether to update the tilt angle currently used by the handheld pointing device 10. In other words, the handheld pointing device 10 determines whether the handheld pointing device 10 is currently in a stationary or moving state according to whether the imaging position of the image frames is greatly moved according to the reference point 21, and determines whether to update the current pointing device 10 for current calculation. The angle of inclination.

The large movement in this embodiment refers to the movement change of the reference point 21 instantaneously (i.e., in a short time, such as several seconds, several milliseconds, or two or more adjacent image frames). That is, the amount of displacement (i.e., displacement change value), moving speed, or acceleration of the reference point 21 at the imaging position of the image frames. Specifically, when the displacement of the reference point 21 at the imaging position of the image frames is greater than a preset displacement threshold, the moving speed of the imaging position is greater than the preset speed change threshold and/or the acceleration of the imaging position is greater than the preset acceleration. At the threshold, it is determined that the reference point 21 is greatly moved at the imaging positions of the image frames without updating the tilt angle currently used by the hand-held pointing device 10.

Then, if it is determined that the reference point 21 does not move substantially at the imaging position of the image frames (that is, the displacement of the reference point 21 between the imaging positions of the image frames is less than a preset displacement threshold, an imaging position) The moving speed is less than the preset speed change threshold and/or the acceleration of the imaging position is less than the preset acceleration threshold, and the relative moving position between the handheld pointing device 10 and the reference point 21 is determined according to the image frames to match the host. The software program executed by 20 controls the operation of the cursor 31 in the video display device 30 correspondingly.

In one embodiment, the handheld pointing device 10 can use an inertial sensor to calculate the tilt angle of the handheld pointing device 10. However, when the user moves the hand-held pointing device 10, the user's application of the hand-held pointing device 10 affects the result of the inertial sensor determining the direction of gravity. Therefore, the tilt angle of the hand-held pointing device 10 must be accurately calculated and updated after the influence of the user's force is excluded.

And when the handheld pointing device 10 is not moved by the user (ie, the reference is detected) When point 21 does not move significantly, it can usually be considered as not being affected by external forces. Since the hand-held pointing device 10 senses the pointing position of the hand-held pointing device 10 by using an image sensor, when the hand-held pointing device 10 is largely moved (ie, the reference point 21 is detected to move largely), The image sensor also synchronously changes the imaging position of the reference point 21 in the image frame. Therefore, the handheld pointing device 10 can determine whether the handheld pointing device 10 is largely moved according to the imaging position of the reference point 21 in the image frame sensed by the image sensor.

In more detail, please refer to FIG. 2 and refer to FIG. 1 at the same time. FIG. 2 is a functional block diagram of a handheld pointing device according to an embodiment of the present invention. The handheld pointing device 10 includes an image capturing unit 11, an acceleration unit 13, a processing unit 15, and a transmission unit 17. The image capturing unit 11 , the acceleration unit 13 , and the transmission unit 17 are respectively coupled to the processing unit 15 .

The image capturing unit 11 is configured to capture an image corresponding to the position of the reference point 21, and sequentially generate a plurality of image frames. Specifically, the image capturing unit 11 can filter the light outside the specific light wave through a filter unit (not shown), so that the image capturing unit 11 senses only the light with a specific light wave emitted by the reference point 21. . The image capturing unit 11 senses the light generated by the reference point 21 according to a preset image capturing frequency (for example, 200 image frames per second), and sequentially generates a plurality of image frames having the reference point 21 image.

In this embodiment, the image capturing unit 11 may be a charge-coupled device (CCD) image sensor or a complementary metal oxide semiconductor (CMOS) image sensor. Implementations, those having ordinary knowledge in the technical field can be designed according to actual use, and the embodiment is not limited herein.

The acceleration unit 13 is configured to sense a plurality of acceleration values of the hand-held pointing device 10 in multiple axial directions (eg, X-axis, Y-axis, and Z-axis, etc.), and generate an acceleration vector. The acceleration unit 13 of the present embodiment may be, for example, a gravity sensor (G-sensor), an accelerometer (also called an accelerometer), and is Built into the handheld pointing device 10. The technical field of the present invention can be designed according to the actual use situation, and the embodiment is not limited thereto.

The processing unit 15 can determine whether the reference point 21 is greatly moved according to the image frames. When the processing unit 15 determines that the reference point 21 has not moved significantly, the reading acceleration unit 13 senses the acceleration values generated by the handheld pointing device 10 on multiple axes to calculate and update the handheld pointing device 10 according to the acceleration values. The first tilt angle currently used is the second tilt angle. The processing unit 15 uses the second tilt angle to calculate the imaging position of the reference point 21 in one of the image frames, that is, the motion vector of the reference point 21.

In an embodiment, the processing unit 15 can sense a plurality of acceleration values of the handheld pointing device 10 in the X axis, the Y axis, and the Z axis according to the acceleration unit 13 and calculate the angle between any two axes. The current tilt angle of the hand-held pointing device 10 is calculated. The processing unit 15 calculates the imaging position of the reference point 21 in one of the image frames according to the second tilt angle and the image frames.

When the processing unit 15 determines that the reference point 21 is displaced, the processing unit 15 may decide not to update the first tilt angle currently used by the hand-held pointing device 10 by determining that the acceleration unit 15 cannot accurately measure the hand-held pointing device 10. In other words, the processing unit 15 will continue to calculate the imaging position of the reference point 21 at one of the image frames using the first tilt angle. The processing unit 15 transmits the motion vector information of the reference point 21 to the host 20 by using the transmission unit 17 in a wireless transmission manner to cooperate with the software program of the host 20 to control the motion of the cursor 31 on the image display device 30.

The tilt angle of the hand-held pointing device 10, such as the first tilt angle and the second tilt angle, is further described below for the processing unit 15.

For example, the image frames corresponding to the position of the reference point 21 generated by the image capturing unit 11 may have a rectangular shape, and the long sides of the image frame are parallel to the X axis, and the short sides of the image frame are parallel to Y. Axial. When the processing unit 15 determines that the reference point 21 is not displaced, the processing unit 15 can drive the acceleration unit 13 to respectively sense the X-axis, the Y-axis, and the Z-axis of the handheld pointing device 10 in the three-dimensional space (3D) shown in FIG. Acceleration values Vx , Vy, and Vz . The acceleration unit 13 can generate an acceleration vector according to the sensing result To generate an acceleration sensing signal, wherein the acceleration sensing signal can represent a ratio of any two acceleration values, such as a ratio of the acceleration value Vx and the acceleration value Vy . The processing unit 15 calculates the current tilt angle of the hand-held pointing device 10 upon receiving the acceleration sensing signal.

In more detail, the processing unit 15 can calculate the acceleration vector of the hand-held pointing device 10 using the following formulas (1) to (3). An angle between each axial direction to obtain the current tilt angle of the hand-held pointing device 10,

Wherein, Vx represents the acceleration value sensed by the acceleration unit 13 in the X-axis; Vy represents the acceleration value sensed by the acceleration unit 13 in the Y-axis; | gxy | represents the gravity calculated from the acceleration value Vx and the acceleration value Vy Gravity acceleration value.

The processing unit 15 then corrects the image frame using the calculation results of equations (1) and (2) to calculate the imaging position of the reference point 21 in one of the image frames. The processing unit 15 can, for example, correct the image frame through the formula (4).

Where x represents the X-axis coordinate of the imaging point of the reference point 21 at one of the image frames; y represents the Y-axis coordinate of the reference point 21 at the imaging position of one of the image frames; x ' represents the corrected reference point 21 The X-axis coordinate of the imaging position of one of the image frames; y ' indicates the Y-axis coordinate of the corrected reference point 21 at the imaging position of one of the image frames. The processing unit 15 can in turn calculate the pointing coordinates or relative motion vector information of the handheld pointing device 10 relative to the reference point 21 or the image display device 30 based on x 'and y '.

Then, the processing unit 15 can calculate that the pointing coordinate or the relative motion vector information of the handheld pointing device 10 relative to the reference point 21 or the image display device 30 is transmitted to the host 20 by using the transmission unit 17 to control the cursor 31 on the image display device 30. Actions.

It should be noted that the acceleration unit 13 used in the hand-held pointing device 10 of the present invention may also be used only to sense acceleration values of two dimensions, for example, only for sensing. Acceleration values Vx and Vx . In other words, the acceleration sensing method of the hand-held pointing device 10 is only an embodiment, and the invention is not limited thereto.

In addition, in this embodiment, the processing unit 15 may be implemented by using a code controller such as a microcontroller or an embedded controller, but the embodiment is not limited. The transmission unit 17 may transmit the mobile vector information to the host 20 by using a Bluetooth transmission method, but the embodiment is not limited thereto.

It should be noted that the types, physical architectures, and/or implementations of the image capturing unit 11, the acceleration unit 13, the processing unit 15, and the transmission unit 17 are based on the type, physical architecture, and/or implementation of the handheld pointing device 10. The setting is not limited to the present invention.

This embodiment further provides a tilt angle correction method for the hand-held pointing device 10 to further illustrate the operation of the hand-held pointing device 10. Referring to FIG. 3 and FIG. 2 simultaneously, FIG. 3 is a schematic flow chart of a method for correcting the tilt angle of the handheld pointing device 10 according to an embodiment of the present invention.

First, in step S301, the image capturing unit 11 of the handheld pointing device 10 captures the corresponding image capturing frequency (for example, 200 image frames per second) when the handheld pointing device 10 points to the reference point 21 The image at the position of the reference point 21 is used to sequentially generate a plurality of image frames.

Next, in step S303, the processing unit 15 of the hand-held pointing device 10 determines whether the reference point 21 is greatly moved according to the image frames. For example, the processing unit 15 can determine whether the reference point 21 is substantially large by analyzing the movement change of the imaging position in the plurality of consecutive image frames (for example, the amount of movement of the reference point 21, the moving speed, and/or the acceleration, etc.) of the reference point 21. mobile.

If the processing unit 15 of the hand-held pointing device 10 determines that the reference point 21 has not moved significantly (i.e., the hand-held pointing device 10 is currently in a stationary state), step S305 is performed. On the other hand, if the processing unit 15 of the hand-held pointing device 10 determines that the reference point 21 has moved largely (that is, the hand-held pointing device 10 is currently in a moving state), step S309 is performed.

Next, in step S305, the processing unit 15 senses the plurality of accelerations of the hand-held pointing device 10 in a plurality of axial directions (for example, the X-axis, the Y-axis, and the Z-axis) by using the acceleration unit 13 of the hand-held pointing device 10. value. Then, in step S307, the processing unit 15 updates the first tilt angle currently used by the handheld pointing device 10 to the second tilt angle according to the acceleration values. The second tilt angle is calculated by the processing unit 15 using the above formulas (1) to (3) based on the acceleration values to calculate the current tilt angle of the hand-held pointing device 10.

In step S309, since the processing unit 15 determines that the reference point 21 is displaced, indicating that the hand-held pointing device 10 is currently in the moving state, the processing unit 15 does not update the first tilting angle of the hand-held pointing device 10. The processing unit 15 calculates the imaging position of the reference point 21 in one of the image frames by using the first tilt angle and the image frames.

Then, the processing unit 15 can transmit the position vector of the calculated reference point 21 to one of the image frames to the host 20 through the transmission unit 17, so as to correspondingly control the action of the upstream target 31 of the image display device 30.

In addition, after performing step S307 or step S309, the processing unit 15 re-executes step S301, capturing the position image corresponding to the reference point 21 and determining whether the reference point 21 is greatly moved to determine whether to update the first tilt of the handheld pointing device 10. angle degree.

As described above, the processing unit 15 can determine whether the reference point 21 is greatly moved according to the continuous movement change of the reference point 21 in the image frames. The following is a further description of a specific embodiment in which the processing unit 15 determines whether the reference point 21 is displaced.

In a specific embodiment, it is determined whether the reference point is displaced according to the speed change of the reference point 21. Referring to FIG. 4 and FIG. 2, FIG. 2 is a schematic flowchart of a method for judging displacement of a hand-held pointing device according to an embodiment of the present invention. The step shown in FIG. 4 may be performed in step S303 of FIG.

In step S401, the processing unit 15 calculates the speed change value of the reference point 21 according to the imaging positions of the first image frame f1 and the second image frame f2 in the image frames corresponding to the reference point 21 generated by the image capturing unit 11. . The first image frame f1 and the second image frame f2 are two consecutive image frames sequentially generated by the image capturing unit 11. That is, the capture time of the second image frame f2 is later than the capture time of the first image frame f1. The imaging position of the reference point 21 in the first image frame f1 is represented by the reference point image 61, and the imaging position of the reference point 21 in the second image frame f2 is represented by the reference point image 61'.

More specifically, the processing unit 15 can calculate the speed change value of the reference point 21 through the formula (5):

Where v represents the speed change value; An imaging position vector indicating the reference point 21 in the first image frame f1, and Is (x1, y1); An imaging position vector representing the reference point 21 in the second image frame f2, and (x2, y2); t _{f 1} represents the extraction time of the first image frame f1; t _{f 2} represents the extraction time of the second image frame f2. Specifically, as shown in FIG. 6A and FIG. 6B, the position of the reference point image 61 of the imaging position of the corresponding reference point 21 in the first image frame f1 (ie, ), or the position of the reference point image 61 ′ corresponding to the imaging position of the reference point 21 in the second image frame f 2 (ie, The processing unit 15 calculates based on the center of the sensing array in the image capturing unit 11 (i.e., the center point of the first image frame f1 and the second image frame f2).

Next, in step S403, the processing unit 15 determines whether the speed change value v is greater than a preset speed change threshold (for example, 1 pixel/unit time) based on the calculated speed change value v . The unit time may be an image capturing frequency according to the image capturing unit (for example, calculating a time interval of each two consecutive image frames according to an image capturing frequency) or a number of continuous image frames (for example, every two consecutive image frames) To define.

When the processing unit 15 determines that the speed change value v is smaller than the preset speed change threshold, step S405 is performed. On the other hand, when the processing unit 15 determines that the speed change value v is greater than the preset speed change threshold, step S407 is performed. The preset speed change threshold may be pre-designed in the processing unit 15 in a firmware manner according to actual application requirements.

In step S405, the processing unit 15 determines that the reference point 21 has not moved significantly in the first image frame f1 and the second image frame f2. In step S407, the processing unit 15 determines that the reference point 21 has moved substantially in the first image frame f1 and the second image frame f2, and the processing unit 15 does not update the first tilt angle currently used by the hand-held pointing device 10.

For example, when the speed change value v calculated by the processing unit 15 according to two consecutive image frames (ie, the first image frame f1 and the second image frame f2) is greater than one pixel, the processing unit 15 can determine the reference point 21 A large movement occurs in the first image frame f1 and the second image frame f2; when the speed change value v calculated by the processing unit 15 is less than 1 pixel, the processing unit 15 can determine the reference point 21 in the first image frame f1 and The second image frame f2 does not move significantly.

In another embodiment, it is determined whether the reference point is greatly moved according to the displacement change of the reference point 21. Please refer to FIG. 1, FIG. 2, FIG. 6A, and FIG. 6B. The processing unit 15 calculates a displacement change value of the reference point 32 at the imaging position of the first image frame f1 and the second image frame f2 according to the continuous first image frame f1 and the second image frame f2 in the image frames (ie, - ). Then, the processing unit 15 can determine whether the displacement change value is smaller than a preset displacement threshold (for example, 5 pixels/unit time) according to the calculated displacement change value.

If the processing unit 15 determines that the displacement change value is less than the displacement threshold (e.g., 5 pixels/unit time), the processing unit 15 can determine that the reference point 21 has not moved significantly. On the other hand, if the processing unit 15 determines that the displacement change value is greater than the displacement threshold, the processing unit 15 can determine that the reference point 21 has not moved significantly and does not update the first tilt angle currently used by the hand-held pointing device 10.

For example, when the processing unit 15 calculates a displacement threshold greater than 5 pixels according to two consecutive image frames (ie, the first image frame f1 and the second image frame f2), the processing unit 15 can determine the reference point 21 A large movement occurs in the first image frame f1 and the second image frame f2; when the displacement threshold calculated by the processing unit 15 is less than 5 pixels, the processing unit 15 can determine the reference point 21 in the first image frame f1 and the second The image frame f2 does not move significantly.

The preset speed change threshold may be pre-designed to the processing unit 15 in a firmware manner according to actual application requirements. The displacement threshold can be pre-designed to the processing unit 15 in a firmware manner according to actual application requirements.

In still another embodiment, it is determined whether the reference point is greatly moved according to the acceleration change of the reference point 21. Referring to FIG. 5 and FIG. 2, FIG. 2, FIG. 6A, FIG. 6B and FIG. 6C, FIG. 5 is a schematic flow chart of a method for judging displacement of a hand-held pointing device according to another embodiment of the present invention. The steps shown in FIG. 5 may be performed in step S303 of FIG. 3, and may also be performed at the handheld pointing device 10 and according to the reference position 21, the imaging position changes (ie, speed change values) of the image frames. It is judged whether or not the reference point 21 is largely moved.

In step S501, the processing unit 15 calculates the corresponding reference point 21 according to the first image frame f1, the second image frame f2, and the third image frame f3 in the image frames corresponding to the reference point 21 generated by the image capturing unit 11. The value of the acceleration change. The first image frame f1, the second image frame f2, and the third image frame f3 are three consecutive image frames sequentially generated by the image capturing unit 11. That is, the capture time of the second image frame f2 is later than the capture time of the first image frame f1, and the capture time of the third image frame f3 is later than the capture time of the second image frame f2.

The processing unit 15 can respectively calculate the reference point 21 between the first image frame f1 and the second image frame f2 and the second image frame f2 and the third image frame f3 through the formula (5) in steps S503 and S505, respectively. The speed change value between the movements. The imaging position of the reference point 21 in the first image frame f1 is represented by a reference point image 61. The imaging position of the reference point 21 in the second image frame f2 is represented by a reference point image 61'. The imaging position of the reference point 21 in the third image frame f3 is represented by a reference point image 61".

For example, the processing unit 15 can calculate the first velocity change value of the reference point 21 between the first image frame f1 and the second image frame f2 and the reference point 21 in the second by using the formula (6) and the formula (7). a second speed change value between the image frame f2 and the third image frame f3. The first speed change value is calculated as follows: Where v ₁ represents a first speed change value; Representing the imaging position of the reference point 21 in the first image frame f1, and Is (x1, y1); Representing the imaging position of the reference point 21 in the second image frame f2, and (x2, y2); t _{f 1} represents the extraction time of the first image frame; t _{f 2} represents the extraction time of the second image frame f2. The formula for calculating the second speed change value is as follows: Where v ₂ represents a second speed change value; Representing the imaging position of the reference point 21 in the second image frame f2; Indicates the imaging position of the reference point 21 in the third image frame f3; t _{f 2} represents the extraction time of the second image frame f2; t _{f 3} represents the extraction time of the third image frame f3. As described above, the position of the reference point image 61 of the imaging position of the corresponding reference point 21 in the first image frame f1 (ie, ), corresponding to the position of the reference point image 61 ′ of the imaging position of the reference point 21 in the second image frame f 2 (ie, And the position of the reference point image 61" corresponding to the imaging position of the reference point 21 in the third image frame f3 (ie, The processing unit 15 calculates the center of the sensing array in the image capturing unit 11 (i.e., the center point "X" of the first image frame f1, the second image frame f2, and the third image frame f3).

Then, in step S505, the processing unit 15 calculates the reference point 21 in the first image frame f1, the second image frame f2, and the third image frame f3 according to the first speed change value v ₁ and the second speed change value v ₂ , respectively. The acceleration change value of the imaging position image (ie, the reference point image 61, 61', 61"). Specifically, the processing unit 15 can calculate the difference between the first speed change value v ₁ and the second speed change value v ₂ . Value, the acceleration change value of the reference point 21 is obtained.

Then, in step S507, the processing unit 15 determines whether the acceleration change value is greater than a preset acceleration threshold (for example, 0g) based on the acceleration change value. When the processing unit 15 determines that the acceleration change value is less than the preset acceleration threshold (for example, 0g), step S509 is performed. On the other hand, when the processing unit 15 determines that the acceleration change value v is greater than the preset acceleration threshold (for example, 0 g), step S511 is performed. The preset acceleration threshold value may be pre-stored in the processing unit 15 according to an actual firmware design.

In step S509, the processing unit 15 determines that the reference point 21 has not moved significantly in the first image frame f1, the second image frame f2, and the third image frame f3. In step S511, when the processing unit 15 determines that the reference point 21 has moved substantially in the first image frame f1, the second image frame f2, and the third image frame f3, the processing unit 15 does not update the current use of the handheld pointing device 10. The first angle of inclination.

In another embodiment, it is determined whether the reference point is greatly moved according to the acceleration change of the hand-held pointing device 10. Please refer to FIG. 7 and FIG. 2 simultaneously. FIG. 7 is a schematic flow chart of a method for judging displacement of a hand-held pointing device according to another embodiment of the present invention. The step shown in FIG. 7 may be performed in step S303 of FIG. 3, and may further determine whether the reference point 21 is determined by the hand-held pointing device 10 according to the position change (ie, the speed change and the acceleration change) of the calculated reference point 21. Execute after a large move.

In step S701, the processing unit 15 of the handheld pointing device 10 senses that the handheld pointing device 10 is currently using the acceleration unit 13 of the handheld pointing device 10. The axial acceleration value to generate an acceleration vector.

Next, in step S703, the processing unit 15 of the handheld pointing device 10 determines whether the magnitude of the acceleration vector is equal to the gravity acceleration value of the handheld pointing device 10 according to the magnitude of the acceleration vector, that is, whether the handheld pointing device 10 is at rest. status. For example, processing unit 15 may calculate the magnitude of the acceleration vector by calculating the square root of the product of the acceleration vectors. When the processing unit 15 determines that the magnitude of the acceleration vector of the hand-held pointing device 10 is equal to the gravitational acceleration value of the hand-held pointing device 10, such as a gravity unit (g), step S707 is performed. On the contrary, when the processing unit 15 determines that the magnitude of the acceleration vector of the hand-held pointing device 10 is not equal to the gravity acceleration value of the hand-held pointing device 10, step S705 is performed.

In step S705, since the acceleration of the hand-held pointing device 10 is not equal to the gravity acceleration value of the hand-held pointing device 10, indicating that the hand-held pointing device 10 is in the moving state, the processing unit 15 can determine that the reference point 21 moves substantially without updating the handheld. The first angle of inclination of the pointing device 10 is currently used. In step S707, since the acceleration of the hand-held pointing device 10 is equal to the gravity acceleration value of the hand-held pointing device 10, indicating that the hand-held pointing device 10 is in a stationary state, the processing unit 15 can determine that the reference point 21 has not moved significantly.

It is worth mentioning that, in practice, the program corresponding to the tilt correction method of FIG. 3 and the reference point displacement judging method described in FIG. 4, FIG. 5 and FIG. 7 may be designed by using a microcontroller or an embedded controller. The code is used by the processing unit 15 to perform the tilt correction method of FIG. 3 and the reference point displacement determination method described in FIGS. 4, 5, and 7, but the embodiment is not limited.

In addition, FIG. 3 is only used to describe a tilt correction method of the handheld pointing device 10, and FIG. 3 is not intended to limit the present invention. Similarly, FIG. 4, FIG. 5, and FIG. 7 are only used to describe the specific manner in which the hand-held pointing device 10 determines whether the reference point is displaced or not, and is not intended to limit the present invention. As shown in FIG. 6A to FIG. 6C, in the present embodiment, the reference point images 61, 61', 61" indicating the imaging positions of the reference point 21 in the first image frame f1, the second image frame f2, and the third image frame f3 are Presented as dots, but In practice, it can also be represented by a shape such as an asterisk, a cross or a triangle according to the actual shape of the reference point 21. In other words, FIG. 6A to FIG. 6C are only used to describe the calculation method of the speed change and the acceleration change of the reference point 21 in conjunction with FIG. 4 and FIG. 5, and are not intended to limit the present invention.

[Another embodiment of the inclination correction method]

From the above-described embodiments, the present invention can further provide a tilt correction method which can be applied to a hand-held pointing device suitable for use in the interactive system of the above embodiment. The tilt correction method may determine whether to update the rotation angle currently used by the handheld pointing device according to the speed change of the reference point, the acceleration change of the reference point, and the acceleration change of the hand-held pointing device.

Referring to FIG. 8 and FIG. 2 simultaneously, FIG. 8 is a schematic flow chart of a method for correcting a tilt angle of a hand-held pointing device according to another embodiment of the present invention. The tilt angle correction method performed by the handheld pointing device of FIG. 8 can be implemented in a firmware programming manner and executed by the processing unit 15 of the handheld pointing device 10. The processing unit 15 can be disposed on the handheld pointing device, for example, a processing chip such as a microcontroller or an embedded controller, but the embodiment is not limited.

First, in step S801, the image capturing unit 11 of the handheld pointing device 10 is based on a preset image capturing frequency (for example, 2000 image frames per second) when the handheld pointing device 10 is pointed to the reference point 21 position. An image corresponding to the position of the reference point 21 is captured, and a plurality of image frames are sequentially generated.

In step S803, the processing unit 15 of the handheld pointing device 10 calculates the first velocity change value of the reference point 21 by using the above formula (6) according to the first image frame and the second image frame in the image frames.

In step S805, the processing unit 15 determines whether the first speed change value is greater than a preset speed change threshold (for example, 1 pixel/unit time) based on the calculated first speed change value. If the processing unit 15 determines that the first speed change value is greater than the preset speed change threshold, step S821 is performed. On the other hand, if the processing unit 15 determines that the first speed change value is smaller than the preset speed change threshold, step S807 is performed.

It is worth mentioning that the unit time may be based on the image capturing frequency of the image capturing unit (for example, calculating the time interval of each two consecutive image frames according to the image capturing frequency) or the number of consecutive image frames (for example, the time interval of the image capturing unit according to the image capturing frequency). For example, every two consecutive image frames) are defined.

In step S807, the processing unit 15 calculates the second speed change value of the reference point 21 by using the foregoing formula (7) according to the second image frame and the third image frame in the image frames.

In step S809, the processing unit 15 calculates the acceleration change value of the reference point 21 using the first speed change value and the second speed change value. That is, the processing unit 15 acquires the acceleration change of the reference point 21 during the extraction time of the first image frame to the third image frame by calculating the difference between the first speed change value and the second speed change value.

Next, in step S811, the processing unit 15 determines whether the acceleration change value is greater than a preset acceleration threshold (for example, 0g). If the processing unit 15 determines that the acceleration change value is greater than the preset acceleration threshold (for example, 0 g), step S821 is performed. On the other hand, if the processing unit 15 determines that the acceleration change value is less than the preset acceleration threshold, step S813 is performed.

In step S813, the processing unit 15 of the hand-held pointing device 10 senses the current acceleration value of the hand-held pointing device 10 in multiple axes by using the acceleration unit 13 of the hand-held pointing device 10 to generate an acceleration vector. In step S815, the processing unit 15 determines whether the magnitude of the acceleration vector of the handheld pointing device 10 is equal to the gravity acceleration value of the handheld pointing device 10, such as a gravity unit (g), to determine whether the handheld pointing device 10 is at a standstill. . In detail, the processing unit 15 can calculate the magnitude of the acceleration vector by calculating the square root of the product of the acceleration vector.

When the processing unit 15 determines that the magnitude of the acceleration vector of the hand-held pointing device 10 is equal to the gravity acceleration value of the hand-held pointing device 10, step S817 is performed. On the other hand, when the processing unit 15 determines that the magnitude of the acceleration vector of the hand-held pointing device 10 is not equal to the gravity acceleration value of the hand-held pointing device 10, step S821 is performed.

In step S817, the processing unit 15 determines that the reference point 21 has not moved significantly, that is, that the hand-held pointing device 10 is currently in a stationary state. Processing unit 15 then In step S819, the first tilt angle currently used by the hand-held pointing device 10 is calculated and updated to the second tilt angle using the equations (1) to (3) according to the acceleration vector sensed by the acceleration unit 13. The processing unit 15 calculates the pointing coordinate or relative motion vector information of the handheld pointing device 10 relative to the reference point 21 or the image display device 30 by using the second tilt angle and one of the image frames.

In step S821, the processing unit 15 determines that the reference point 21 is largely moved, that is, the hand-held pointing device 10 is currently in a moving state. In step S823, the processing unit 15 does not update the first tilt angle currently used by the hand-held pointing device 10 because it has been determined that the reference point 21 has moved substantially. The processing unit 15 calculates the pointing coordinates or relative motion vector information of the handheld pointing device 10 relative to the reference point 21 or the image display device 30 by using the first tilt angle and one of the image frames.

The processing unit 15 can then control the transmission unit 17 to calculate the pointing coordinates or relative motion vector information of the handheld pointing device 10 relative to the reference point 21 or the image display device 30, and wirelessly transmit the information to the host 20 to cooperate with the software program executed by the host 20. Accordingly, the operation of the upstream target 31 of the image display device 30 is controlled accordingly.

After performing step S819 or step S823, the processing unit 15 re-executes step S801, captures the position image corresponding to the reference point 21, and determines whether the reference point 21 is displaced to determine whether to update the first tilt angle of the handheld pointing device 10.

In addition, FIG. 8 is only used to describe a tilt correction method of the handheld pointing device 10, and thus FIG. 8 is not intended to limit the present invention. Those with ordinary knowledge in the technical field can also choose the way to judge whether the reference point moves greatly according to the actual operation requirements. In other words, in practice, steps S803 to S805 (ie, the speed change of the reference point 21), steps S807 to S811 (ie, the acceleration change of the reference point 21), and S813 to S815 (ie, the acceleration change of the hand-held pointing device 10) may be based on Actual operational requirements, choose whether to execute or skip.

Those skilled in the art can also determine whether the reference point 21 is greatly moved by calculating the displacement change of the reference point 21 before calculating the speed change of the reference point 21. In detail, before performing step S803, the processing unit 15 may The displacement change value of the reference point 21 at the imaging position of the first image frame and the second image frame is calculated according to the first image frame and the second image frame. Then, the processing unit 15 determines whether the displacement change value is smaller than a preset displacement threshold (for example, 5 pixels/unit time) based on the calculated displacement change value to determine whether the reference point 21 is largely moved.

In addition, the preset speed change threshold, the preset acceleration threshold, and the displacement threshold may be set according to the application of the actual handheld pointing device 10, which is not limited in this embodiment.

[Another embodiment of the inclination correction method]

From the above-described embodiments, the present invention can further provide a tilt correction method which can be applied to a hand-held pointing device suitable for use in the interactive system of the above embodiment. The tilt correction method can determine whether to update the rotation angle currently used by the handheld pointing device according to the acceleration change of the reference point.

Referring to FIG. 9 and FIG. 1 and FIG. 6A to FIG. 6C, FIG. 9 is a schematic flow chart of a method for correcting a tilt angle of a hand-held pointing device according to another embodiment of the present invention. The tilt angle correction method performed by the hand-held pointing device of FIG. 9 can be implemented in a firmware programming manner and executed by the processing unit 15 in the hand-held pointing device. The processing unit 15 can be disposed on the handheld pointing device, for example, a processing chip such as a microcontroller or an embedded controller, but the embodiment is not limited.

In step S901, the image capturing unit 11 of the handheld pointing device 10 captures the image corresponding to the position of the reference point 21 according to the preset image capturing frequency when the handheld pointing device 10 points to the position of the reference point 21, and The sequence produces multiple image frames.

Then, in step S903, the processing unit 15 of the handheld pointing device 10 calculates the acceleration change value of the imaging position of the reference point 21 in the consecutive image frames according to any three consecutive image frames in the image frames. The capture time of the third image frame f3 in any three consecutive image frames is later than the capture time of the second image frame f2, and the capture time of the second image frame f2 is later than that of the first image frame f1. Take time.

Specifically, the processing unit 15 can use the foregoing imaging positions of the first image frame f1 and the second image frame f2 in the three consecutive image frames according to the reference point 21, that is, the position vectors of the reference point images 61, 61 ′, Equation (6) calculates the first speed change value of the reference point 21. Then, according to the imaging position of the second image frame f2 and the third image frame f3 in the three consecutive image frames according to the reference point 21, that is, the position vector of the reference point images 61', 61", the foregoing formula is used ( 7) Calculating a second speed change value of the reference point 21. The processing unit 15 may then calculate the acceleration change value of the reference point 21 using the first speed change value and the second speed change value.

In step S905, the processing unit 15 determines that the reference point 21 is in three consecutive directions according to the acceleration change values of the imaging positions (ie, the reference point images 61, 61', and 61" in the three consecutive image frames of the reference point 21. Whether the acceleration change value of the imaging position (that is, the reference point images 61, 61' and 61") in the image frame is equal to zero (ie, 0 g). If the processing unit 15 determines that the acceleration change value of the imaging position of the reference point 21 in the three consecutive image frames (ie, the reference point images 61, 61', and 61") is equal to zero, step S907 is performed. Otherwise, if the processing unit 15 When it is judged that the acceleration change value of the imaging position of the reference point 21 in the three consecutive image frames (that is, the reference point images 61, 61' and 61") is not equal to zero, step S911 is performed.

In step S907, when the processing unit 15 determines that the reference point 21 has not moved significantly, and the processing unit 15 senses the acceleration value of the hand-held pointing device 10 in the multi-axis by the acceleration unit 13 of the handheld pointing device 10 to generate Acceleration vector. Next, in step S909, the processing unit 15 may calculate and update the first tilt angle currently used by the hand-held pointing device 10 as the second tilt angle using the aforementioned formulas (1) to (3). The processing unit 15 calculates the pointing coordinates or relative motion vector information of the handheld pointing device 10 with respect to the reference point 21 or the image display device 30 by using the second tilt angle and one of the three consecutive image frames.

In step S911, the processing unit 15 determines that the reference point 21 has moved largely, and does not update the first tilt angle currently used by the hand-held pointing device 10. The processing unit 15 calculates the hand-held finger by using the first tilt angle and one of the image frames Pointing coordinates or relative motion vector information to device 10 relative to reference point 21 or image display device 30.

The processing unit 15 can then control the transmission unit 17 to wirelessly transmit the pointing coordinates or relative motion vector information of the calculated reference point 21 hand-held pointing device 10 to the host 20 to cooperate with the software program executed by the host 20, and accordingly control the image display. The operation of the upstream tag 31 of the device 30.

After performing step S909 or step S911, the processing unit 15 re-executes step S901, extracts the position image corresponding to the reference point 21, and determines whether the reference point 21 is displaced to determine whether to update the first tilt angle of the handheld pointing device 10.

In addition, FIG. 9 is only used to describe a tilt correction method of the handheld pointing device 10, and FIG. 9 is not intended to limit the present invention. Those having ordinary knowledge in the technical field can also increase the step of using the movement change of the reference point 21 (ie, the displacement change and the speed change) according to the actual operational requirements as the basis for determining whether the reference point 21 is displaced.

[Possible effects of the examples]

In summary, the embodiment of the present invention provides a handheld pointing device and a tilt angle correcting method thereof. The handheld pointing device and the tilt angle correcting method thereof can calculate the position of the reference point at a time by using a reference point and an accelerometer. The above changes, and actively determine whether to use the acceleration information generated by the accelerometer on the handheld pointing device to correct the tilt angle of the handheld pointing device. The invention can utilize the firmware design method to make the handheld pointing device determine whether the reference point moves greatly by calculating and analyzing the speed change of the reference point, the acceleration change of the reference point, and the acceleration change of the hand-held pointing device. Decide whether to correct the tilt angle of the handheld pointing device.

Accordingly, the hand-held pointing device of the present invention can effectively and accurately calculate the position of the reference point without adding a gyroscope or using two reference points, simplifying the hardware structure of the hand-held pointing device, and reducing the hand-held The design and manufacturing cost of the pointing device.

The above description is only an embodiment of the present invention, and is not intended to limit the invention. Benefit range.

S301~S309‧‧‧Step procedure

Claims (28)

A method for correcting a tilt angle of a hand-held pointing device, comprising: capturing an image corresponding to a position of a reference point when the handheld pointing device is pointed to a reference point, and sequentially generating a plurality of image frames; The image frame determines whether the reference point moves substantially; and if it is determined that the reference point does not move substantially, an acceleration unit of the handheld pointing device senses a plurality of acceleration values of the handheld pointing device in multiple axial directions to Calculating and updating a first tilt angle currently used by the handheld pointing device according to the acceleration values is a second tilt angle. The tilt angle correction method of claim 1, further comprising: if the reference point is determined to move substantially, the first tilt angle of the handheld pointing device is not updated, and the first tilt angle is used to calculate the The reference point is at the position of one of the image frames. The tilt angle correction method according to claim 1, wherein determining whether the reference point is greatly moved is determining whether the imaging position of the reference point in the image frames is greatly moved. The tilt angle correction method of claim 1, wherein the step of determining whether the reference point is greatly moved comprises: capturing a first image frame and a second image in the image frames according to the method a frame, calculating a displacement change value of the reference point at an imaging position of the first image frame and the second image frame; determining whether the displacement change value is less than a displacement threshold; and if the displacement change value is less than the displacement threshold , it is determined that the reference point does not move significantly. The tilt angle correction method of claim 1, wherein the step of determining whether the reference point is greatly moved comprises: capturing a first image frame and a second image frame in the image frames according to the method Calculating an imaging position of the reference point in the first image frame and the second image frame Setting a speed change value; determining whether the speed change value is greater than a preset speed change threshold; and if the speed change value is less than the preset speed change threshold, determining that the reference point does not move significantly. The tilt angle correction method according to claim 5, wherein the speed change value is calculated as follows: Where v represents the speed change value; Representing the reference point of the imaging position of the second image frame; Indicates the imaging position of the reference image in the first image frame; t _{f 2} represents the capturing time of the second image frame; t _{f 1} represents the capturing time of the first image frame. The tilt angle correction method of claim 1, wherein the step of determining whether the reference point is greatly moved comprises: selecting a first image frame and a second image in the captured image frames. a frame, calculating a first speed change value of the reference point at an imaging position of the first image frame and the second image frame; and selecting the second image frame and the third image frame in the image frames according to the captured image frame Calculating a second speed change value of the reference point at the imaging position of the second image frame and the third image frame; acquiring the difference according to the difference between the first speed change value and the second speed change value An acceleration change value of the reference point; determining whether the acceleration change value is greater than a preset acceleration threshold; and if the acceleration change value is less than the preset acceleration threshold, determining that the reference point does not move significantly. The tilt angle correction method according to claim 7, wherein the first speed change value is calculated as follows: Where v ₁ represents the first speed change value; Representing the reference point of the imaging position of the second image frame; Indicates an imaging position of the reference image in the first image frame; t _{f 2} represents a capture time of the second image frame; t _{f 1} represents a capture time of the first image frame; wherein the second speed change value Calculated as follows: Where v ₂ represents the second speed change value; Representing the reference point of the imaging position of the third image frame; Indicates the imaging position of the reference image in the second image frame; t _{f 3} represents the capturing time of the third image frame; t _{f 2} represents the capturing time of the second image frame. The tilt angle correction method according to claim 7, wherein the step of determining whether the reference point is greatly moved comprises: using the acceleration unit to sense the acceleration of the handheld pointing device currently in multiple axes a value to generate an acceleration vector; determining whether the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device; and determining the reference if the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device The point did not move significantly. The tilt angle correction method according to claim 1, wherein the step of determining whether the reference point is greatly moved comprises: using the acceleration unit to sense the acceleration of the handheld pointing device currently in multiple axes a value to generate an acceleration vector; determining whether the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device; and if the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device, determining that the reference point is not Moved a lot. A method for correcting a tilt angle of a handheld pointing device includes: capturing an image corresponding to a position of a reference point when the handheld pointing device is pointed to a reference point, and sequentially generating a plurality of image frames; according to the image frames Any three consecutive image frames, calculating an acceleration change value of the reference point at the imaging position of the continuous image frames; determining whether the acceleration change value is equal to zero; and if the acceleration change value is equal to zero, using the handheld pointing device An acceleration unit senses a plurality of acceleration values of the handheld pointing device in a plurality of axes to calculate and update a first tilt angle currently used by the handheld pointing device to be a second tilt angle according to the acceleration values. The tilt angle correction method of claim 11, wherein after determining that the acceleration change value is equal to zero, the method further comprises: using the acceleration unit to sense the acceleration values of the handheld pointing device currently in multiple axes Generating an acceleration vector; determining whether the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device; if the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device, calculating and updating the handheld according to the acceleration values The first tilt angle currently used by the pointing device is the second tilt angle. The tilt angle correction method of claim 11, wherein the step of calculating the acceleration change value of the reference point comprises: capturing a first image frame and a second one of the three consecutive image frames according to the method An image frame, calculating a first velocity change value of the reference point at an imaging position of the continuous image frames; calculating the reference according to the second image frame and a third image frame in any three consecutive image frames a second velocity change value at an imaging position of the continuous image frames; and a difference between the first velocity change value and the second velocity change value Taking the acceleration change value of the reference point at the imaging position of the continuous image frames. The tilt angle correction method according to claim 12, wherein the first speed change value is calculated as follows: Where v ₁ represents the first speed change value; Representing the reference point of the imaging position of the second image frame; Indicates an imaging position of the reference image in the first image frame; t _{f 2} represents a capture time of the second image frame; t _{f 1} represents a capture time of the first image frame; wherein the second speed change value Calculated as follows: Where v ₂ represents the second speed change value; Representing the reference point of the imaging position of the third image frame; Indicates the imaging position of the reference image in the second image frame; t _{f 3} represents the capturing time of the third image frame; t _{f 2} represents the capturing time of the second image frame. A handheld pointing device includes: an image capturing unit for capturing an image corresponding to a reference point position, and sequentially generating a plurality of image frames; and an acceleration unit for sensing the handheld pointing device a plurality of acceleration values in the axial direction, and generating an acceleration vector; and a processing unit coupled to the image capturing unit and the acceleration unit, the processing unit determining, according to the image frames, whether the reference point moves substantially; When the processing unit determines that the reference point does not move substantially, the reading the acceleration unit senses the acceleration values generated by the handheld pointing device on multiple axes, and calculates and updates the handheld pointing device according to the acceleration values. A first tilt angle used is a second tilt angle. The hand-held pointing device of claim 15, wherein the processing unit does not update the hand-held finger when the processing unit determines that the reference point moves substantially To the first tilt angle currently used by the device, and using the first tilt angle to calculate an imaging position of the reference point to one of the image frames. The hand-held pointing device of claim 15, wherein the processing unit calculates the reference point in the first image frame according to a first image frame and a second image frame captured in the image frames. And a displacement change value of the imaging position of the second image frame to determine whether the reference point is greatly moved at an imaging position of the first image frame and the second image frame according to the displacement change value. The hand-held pointing device of claim 15, wherein the processing unit calculates the reference point in the first image frame according to a first image frame and a second image frame captured in the image frames. And a speed change value of the imaging position of the second image frame, to determine whether the reference point is greatly moved at an imaging position of the first image frame and the second image frame according to the speed change value. The hand-held pointing device of claim 18, wherein the processing unit calculates the speed change value by using the following formula: Where v represents the speed change value; Representing the reference point of the imaging position of the second image frame; Indicates the imaging position of the reference image in the first image frame; t _{f 2} represents the capturing time of the second image frame; t _{f 1} represents the capturing time of the first image frame. The hand-held pointing device of claim 15, wherein the processing unit calculates a first image frame and a second image frame in the image frames to generate a corresponding reference point in the first image frame. And a first speed change value of the imaging position of the second image frame, the processing unit calculates the second image frame and the third image frame in the image frames, and generates a corresponding reference point at the first a second speed change value of the image frame and the image forming position of the second image frame; wherein the processing unit calculates the first speed change value and the second speed change value And a difference value of the acceleration of the reference image at the imaging position of the first image frame and the second image frame to determine whether the imaging position of the reference point is greatly moved according to the acceleration change value. The hand-held pointing device of claim 20, wherein the processing unit calculates the first speed change value by using the following formula, Where v ₁ represents the first speed change value; Representing the reference point of the imaging position of the second image frame; Representing the imaging position of the reference image in the first image frame; t _{f 2} indicating the capturing time of the second image frame; t _{f 1} indicating the capturing time of the first image frame; wherein the processing unit uses the following formula Calculating the second speed change value, Where v ₂ represents the second speed change value; Representing the reference point of the imaging position of the third image frame; Indicates the imaging position of the reference image in the second image frame; t _{f 3} represents the capturing time of the third image frame; t _{f 2} represents the capturing time of the second image frame. The hand-held pointing device of claim 15, wherein the acceleration unit is an accelerometer or a gravity sensor. A handheld pointing device includes: an image capturing unit for capturing an image corresponding to a reference point position, and sequentially generating a plurality of image frames; and an acceleration unit for sensing the handheld pointing device a plurality of acceleration values in the axial direction and generating an acceleration vector; and a processing unit coupled to the image capturing unit and the acceleration unit, wherein the processing unit calculates the image according to any three consecutive image frames in the image frames An acceleration change value of the reference point at the imaging position of the continuous image frames; When the processing unit determines that the acceleration change value is zero, the reading the acceleration unit senses the acceleration values generated by the handheld pointing device in multiple axes to calculate and update the handheld pointing according to the acceleration values. A first tilt angle currently used by the device is a second tilt angle. The hand-held pointing device of claim 23, wherein when the processing unit determines that the acceleration change value is zero, the processing unit determines whether the magnitude of the acceleration vector is equal to a gravity acceleration value of the handheld pointing device, And when the magnitude of the acceleration vector is equal to the gravity acceleration value of the handheld pointing device, the first tilt angle currently used by the handheld pointing device is calculated and updated according to the acceleration values as the second tilt angle. The hand-held pointing device of claim 23, wherein the processing unit calculates a first image frame and a second image frame of any three consecutive image frames captured to generate a corresponding reference point. And processing, by the processing unit, the second image frame and the third image frame in the image frames captured by the first image frame and the image frame of the second image frame, Generating a second speed change value corresponding to the imaging position of the second image frame and the third image frame; wherein the processing unit calculates a difference between the first speed change value and the second speed change value And obtaining the acceleration change value of the reference point at the imaging position of the first image frame and the third image frame. The hand-held pointing device of claim 25, wherein the processing unit calculates the first speed change value by using the following formula, Where v ₁ represents the first speed change value; Representing the reference point of the imaging position of the second image frame; Representing the imaging position of the reference image in the first image frame; t _{f 2} indicating the capturing time of the second image frame; t _{f 1} indicating the capturing time of the first image frame; wherein the processing unit uses the following formula Calculating the second speed change value, Where v ₂ represents the second speed change value; Representing the reference point of the imaging position of the third image frame; Indicates the imaging position of the reference image in the second image frame; t _{f 3} represents the capturing time of the third image frame; t _{f 2} represents the capturing time of the second image frame. The hand-held pointing device of claim 23, wherein the acceleration unit is an accelerometer or a gravity sensor. The hand-held pointing device of claim 23, wherein the processing unit determines that the acceleration change value of the reference point in the imaging position of the continuous image frames exceeds a predetermined acceleration threshold when the processing unit determines The first tilt angle currently used by the handheld pointing device is not updated, and the position of the reference point to one of the image frames is calculated using the first tilt angle.