Patent Publication Number: US-2004048663-A1

Title: Photographic pointer positioning device

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] The present invention relates to a pointer positioning device adapted to control the positioning of a pointer on a display screen and, more particularly, to a photographic pointer positioning device that controls the positioning of a pointer on a display screen by means of photography. Instead of the functioning of a conventional light-gun of using bullet drop point signal or synchronous signal to obtain the coordinate value, the invention uses a video camera to photograph the display area of the display screen so as to obtain the actual coordinate values of the aiming point of the video camera at the display screen through the processing of an image processing circuit and the computing of a computing unit. The photographic pointer positioning device can be used in any of a variety of display screens to play a shooting game.  
       [0003] 2. Description of the Related Art  
       [0004] For the advantages of fine picture quality of low manufacturing cost, picture tubes have been intensively used in TV and computer monitors since 1897. However, facing the challenge of a variety of TFT (thin-film transistor) LCDs, PDPs (plasma display panels), FPD (flat-panel displays), the leading role of picture tube displays becomes unstable. After 1990, TFT LCDs and PDPs have become more and more popularly accepted in the market. In addition to picture tube displays, there are known about ten kinds of display related techniques under developing. It is expected that TFT LCDs will take over the leading role of picture tube displays in the market in the near future. Nowadays, big size TFT LCDs have been intensively used in desktop computers instead of CDTs.  
       [0005] Further, since the commercialization of PDPs in 1985, big size products have been continuously disclosed. During “The 1998 Nagano Olympic Winter Game”, Japanese manufactures announced various newly developed PDPs.  
       [0006] Following PDPs, various projection systems are developed. For example, Barker Belgium disclosed a LCD projection system—“Reality 9200” that is capable of processing 200 million pixels per second to provide high resolution picture under bright illumination. Japan JVC also developed “Direct Drive Light Amplifier; D-DLA” by means of the application of LCD projection technology. “Direct Drive Light Amplifier; D-DLA” shows HDTV picture standards, or a high-resolution level next to S-XGA computer. US Texas Instrument disclosed a projection technology called DMD that provides clear and bright picture quality. These creations are still not satisfactory in function for the disadvantages of short service life of projection lights (about 250-500 hours) and high noise level of cooling fans. Further, there are well developed 3D projection systems using laser or hologram technology.  
       [0007] As indicated above, the development of display technology is fast. Similar to the development of TFT LCDs and PDPs, FEDs (Field emission displays) have been developed after CRT and CDT displays. Competition in the flat-panel display market is severe. Neither type of flat-panel displays shows a significant victory in the market.  
       [0008] In current shooting games, a light-gun may be used instead of a joystick to aim at the objective on the display screen, increasing the reality of the simulation of the game. In order to fit the design of game programs to be executed in the main unit of a game machine, second generation light-guns are developed within a short time after creation of first generation light-guns. A first generation light-gun lets the game program compute the coordinate values. A second generation light-gun computes the coordinate values of the aiming point at the display screen, and then feeds the coordinate values back to the main unit of the game machine. FIG. 1 illustrates a wired first generation light-gun  70  used with a game machine main unit  80 . As illustrated, the signal cable of the light-gun  70  is directly connected to the connector of the game machine main unit  80 . When the player aimed the light-gun  70  at the display screen  10  and fired a bullet drop point signal, the photo receiver  30  of the light-gun  70  receives a bullet drop point signal produced from the striking of CRT electrons against the aiming point of the light-gun  70  at the display screen  10  and then sends the signal back to the game machine main unit  80 , thereby causing the game program running in the game machine main unit  80  to compute the coordinates of the aiming point of the light-gun  70  at the display screen  10  subject to the bullet drop point signal received from the photo-receiver  30  and the video signal  60  of the game machine main unit  80  for further game program processing.  
       [0009] According to conventional first generation light-guns and second generation light-guns, the bullet drop point signal processing or X, Y coordinate values computing of bullet drop point is executed subject to the bullet drop point signal or synchronous signal provided by the display screen. Further, conventional first generation light-guns and second generation light-guns cannot be used with a TFT LCD, PDP, projection system display screen, or any display means that cannot produce a bullet drop point signal or synchronous signal. Therefore, light-guns can only be used with a CDT or CRT display.  
       SUMMARY OF THE INVENTION  
       [0010] The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a photographic pointer positioning control device, which is suitable for use with any of a variety of display screens to control the positioning of the pointer. It is another object of the present invention to provide a photographic pointer positioning control device, which can be used in a computer system instead of a mouse, tablet, or light-gun. To achieve these and other objects of the present invention, the photographic pointer positioning control device comprises a video camera adapted to photograph the display area of the display screen, an image processing circuit adapted to process the video signal obtained from the video camera through an image out-line and verification processing process, and a computing unit adapted to compute the processed data into coordinate values corresponding to the aiming point of the video camera at the display screen, and a communication interface adapted to transmit the coordinate values to the game machine main unit for further processing. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0011]FIG. 1 is a system block diagram showing the use of a wired light gun in a firing game according to the prior art.  
     [0012]FIG. 2 is a block diagram of a photographic pointer positioning control device according to the first embodiment of the present invention.  
     [0013]FIG. 2A is a circuit diagram of the photographic pointer positioning control device according to the first embodiment of the present invention.  
     [0014]FIG. 3 is a flow chart explaining the operation steps of the first embodiment of the present invention.  
     [0015]FIG. 4 is a block diagram of a photographic pointer positioning control device according to the second present invention.  
     [0016]FIG. 5 is a flow chart explaining the operation steps of the second embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
     [0017] Referring to FIGS. 2 and 2A, a photographic pointer positioning control device  200  according to the first present invention has a communication interface  220  for connection to a game machine main unit  20 , which has a display screen  10  connected thereto. The photographic pointer positioning control device  200  comprises a control unit  210 , a video camera  230 , and a set of buttons  240 .  
     [0018] The control unit  210  comprises a control circuit  211 , a computing unit  212 , and an image processing circuit  213 . The control circuit  211  is electrically connected to the buttons  240 . The user can operate the buttons  240  to control the operation of the control circuit  211 . The video camera  230 , the computing unit  212 , and the image processing circuit  213  are respectively electrically connected to the control circuit  211 . The control circuit  211  controls the video camera  230  to photograph the whole display area of the display screen  10 , and to transmit photographed video signal to the control circuit  211 . Upon receipt of photographed video signal from the video camera  230 , the control circuit  211  sends the signal to the image processing circuit  213  for image out-line and verification processing. The processed data thus obtained is then sent back to the control circuit  211  by the image processing circuit  213 , so that the control circuit  211  inputs the processed video signal into the computing unit  212 , enabling the computing unit  212  to compute the actual values of the coordinates of the aiming point of the video camera  230  at the display screen  10 . The computing unit  212  outputs the computed coordinate values to the control circuit  211 , enabling the computed coordinate values to be transmitted to the game machine main unit  20  by the control circuit  211  through the communication interface  220 , so that the game machine main unit  20  can run the related program subject to the received coordinate values.  
     [0019] However, the control circuit  211 , computing unit  212  and image processing circuit  213  of the control unit  210  of the aforesaid photographic pointer positioning control device  200  are integrated in a single chip JCH0810X. The video camera  230  is a CMOS sensor. The communication interface  220  corresponds to CONI PSCON. The buttons  240  correspond to switches SW 1 ˜SW 7 .  
     [0020] Further, the control circuit  211  and computing unit  212  of the aforesaid control unit  210  can be integrated in a single chip and connected to the image processing circuit  213 .  
     [0021] Referring to FIG. 3 and FIGS. 2 and 2A again, when the user using the game machine main unit  20 , the photographic pointer positioning control device  200  and the display screen  10  to run a game program, the control circuit  211  proceeds subject to the following coordinate value computing and verification procedure, which include the steps of:  
     [0022] 100  Start;  
     [0023] 110  Control the video camera  230  to photograph the whole display area of the display screen  10 , and then drive the video camera  230  to transmit photographed video signal to the control circuit  211 ;  
     [0024] 120  Transmit the video signal received from the video camera  230  to the image processing circuit  213  for image out-line and verification processing, and then drive the image processing circuit  213  to transmit processed signal to the control circuit  211 ;  
     [0025] 130  Identify data obtained from the image processing circuit  213  with the pixels of the video camera  230  so as to obtain the coordinate values of the four corners of the display area of the display screen  10  in the photographed image;  
     [0026] 140  Send the coordinate values of the four corners of the display area of the display screen  10  in the photographed image and the coordinate values of the center point of the video camera  230  to the computing unit  212 , and then drive the computing unit  212  to put these coordinate values into a distance formula, so as to obtain the side lengths of the sides of the display area of the display screen  10  in the image;  
     [0027] 150  Drive the computing unit  212  to compute the ratio between the computed side lengths and the actual side lengths of the display screen  10 , and then multiply the side lengths of the display area of the display screen  10  in the image by the ratio so as to obtain the values of the side lengths at the display screen  10 , and then drive the computing unit  212  to send the actual side lengths data to the control circuit  211 ;  
     [0028] 160  Use the actual side lengths thus obtained from the computing unit  212  to write an affected quadratic simultaneous equation with two unknown, and then send the related data to the computing unit  212 , for enabling the computing unit  212  to find the solution of the affected quadratic simultaneous equation with two unknown by means of the data obtained and to feed the X, Y values thus obtained to the control circuit  211 ;  
     [0029] 170  Receive the X, Y values from the computing unit  212 , and judge the X, Y values to be the coordinate values of the aiming point of the video camera  230 , and then send the data through the communication interface  220  to the game machine main unit  20 , for enabling the game machine main unit  20  to run the program subject to the coordinate values of the aiming point of the video camera  230 ;  
     [0030] 180  End.  
     [0031]FIG. 4 shows a photographic pointer positioning control device  400  according to the second embodiment of the present invention. This second embodiment is similar to the aforesaid first embodiment with the exception of the processing of the video signal from the video camera. According to the first embodiment of the present invention as shown in FIG. 2, the coordinate values of the actual display area of the display screen  10  and the coordinate values of the aiming point of the video camera  230  are directly computed in the photographic pointer positioning control device  200  and then sent to the game machine main unit  20 . According to the second embodiment of the present invention, video signal is directly sent to the game machine main unit  450  before processing, and the game machine main unit  450  processes the video signal to obtain the coordinate values of the actual display area of the display screen  10  and the coordinate values of the aiming point of the video camera  230 .  
     [0032] Referring to FIG. 4 again, the photographic pointer positioning control device  400  comprises a communication interface  420  connected to the game machine main unit  450 , a control circuit  410 , a video camera  430 , and a set of buttons  440 . The control circuit  410  is respectively electrically connected to the video camera  430  and the buttons  440 . The user can operate the buttons  440  to control the operation of the control circuit  410 .  
     [0033] Referring to FIG. 5 and FIG. 4 again, when the user using the game machine main unit  450 , the photographic pointer positioning control device  400  and the display screen  10  to run a game program, the control circuit  410  proceeds subject to the following coordinate value computing and verification procedure, which include the steps of:  
     [0034] 300  Start;  
     [0035] 310  The control circuit  410  controls the video camera  430  to photograph the whole display area of the display screen  10  and then to transfer photographed video signal to the control circuit  410 ;  
     [0036] 320  The control circuit  410  transfers the received video signal to the game machine main unit  450  through the communication interface  420 ;  
     [0037] 330  The game machine main unit  450  processes the video signal received from the control circuit  410  through an image out-line and verification processing procedure;  
     [0038] 340  The game machine main unit  450  identifies the processed data with the pixels of the video camera  430  so as to obtain the coordinate values of the four corners of the display area of the display screen  10  in the photographed image;  
     [0039] 350  The game machine main unit  450  puts the coordinate values of the four corners of the display area of the display screen  10  in the photographed image and the coordinate values of the center point of the video camera  430  into a distance formula, so as to obtain the side lengths of the sides of the display area of the display screen  10  in the photographed image;  
     [0040] 360  The game machine main unit  450  computes the ratio between the computed side lengths and the actual side lengths of the display screen  10 , and then multiplies the side lengths of the display area of the display screen  10  in the photographed image by the ratio so as to obtain the values of the actual side lengths at the display screen  10 ;  
     [0041] 370  The game machine main unit  450  uses the actual side lengths thus obtained to write an affected quadratic simultaneous equation with two unknown, and then finds the solution of the affected quadratic simultaneous equation with two unknown by means of the data obtained, and the solution thus obtained is the X, Y values of the aiming point of the photographic pointer positioning control device  400 ;  
     [0042] 380  Output the coordinate values of the aiming point of the video camera  430  to the display screen  10 , and run the game program;  
     [0043] 390  End.  
     [0044] Referring to FIGS. 2 and 4 again, the photographic pointer positioning control device can also be used in a computer system, big scale game machine, video game machine, or computer terminal system. When used in a computer system, the photographic pointer positioning control device replace the function of a mouse, tablet, or light-gun.  
     [0045] The communication interface  220  or  420  of the photographic pointer positioning control device  200  or  400  can be a USB (universal serial bus) interface, 1394 interface, PS2 interface, or any of a variety of suitable connection interfaces connectable to the game machine main unit  20  or  450  through a signal line for enabling the control circuit  211  or  410  to transmit signal through a wired communication method.  
     [0046] According to the present invention, the communication interface  220  or  420  is a wireless transmitting receiving interface having radio transmitter receiver circuit means. The game machine main unit  20  or  450  has a corresponding radio transmitter receiver circuit means for signal transmission with the control circuit  211  or  410  wirelessly.  
     [0047] A prototype of photographic pointer positioning control device has been constructed with the features of the annexed drawings of FIGS.  2 ˜ 5 . The photographic pointer positioning control device functions smoothly to provide all of the features discussed earlier.  
     [0048] Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. Accordingly, the invention is not to be limited except as by the appended claims.