Patent Publication Number: US-2007118820-A1

Title: Equipment control apparatus, remote controller, equipment, equipment control method, and equipment control program product

Description:
This nonprovisional application is based on Japanese Patent Application No. 2005-297876 filed with the Japan Patent Office on Oct. 12, 2005, the entire contents of which are hereby incorporated by reference.  
     FIELD OF THE INVENTION  
      The present invention relates to an equipment control apparatus, a remote controller, equipment, an equipment control method, and an equipment control program product, and particularly to an equipment control apparatus controlling every equipment in a non-contact manner by converting data, a remote controller, equipment, an equipment control method, and an equipment control program product.  
     DESCRIPTION OF THE BACKGROUND ART  
      Japanese Patent Laying-Open No. 06-153017 discloses a remote control apparatus including a monitor, an infrared camera detecting an image of a human body, and a CPU (Central Processing Unit) for controlling the display of the image of the human body detected by the infrared camera and superimposed control item areas for controlled equipment on a monitor screen, and when the image of the human body overlaps with the control item by a prescribed amount or more in the display screen, outputting a control instruction as to the overlapped control item to the controlled equipment.  FIG. 10  illustrates an exemplary image of the human body displayed on the monitor of the remote control apparatus according to Japanese Patent Laying-Open No. 06-153017.  FIG. 11  is a diagram illustrating a configuration of the remote control apparatus according to Japanese Patent Laying-Open No. 06-153017. When the remote control apparatus according to Japanese Patent Laying-Open No. 06-153017 is used, a user controls the controlled equipment by moving his/her own arms and legs while the user views the monitor on which his/her own body is displayed.  
      According to the invention disclosed in Japanese Patent Laying-Open No. 06-153017, as remote control is permitted while the human body is displayed on the monitor, a remote control device kept on hand is not necessary and the equipment can remotely be controlled from the same place. Examples of remotely controlled equipment include a television, an air conditioner, a personal computer, a video game machine, a portable phone, and the like.  
      Japanese Patent Laying-Open No. 2001-307107 discloses an image processing apparatus including a video camera which picks up an image of an object making gestures or hand gestures, a gesture recognition unit identifying the image picked up by the video camera, a region division unit dividing the image identified by the gesture recognition unit into prescribed regions, a motion detection unit detecting a direction of motion within the region obtained as a result of division by the region division unit, a gravity center calculation unit calculating the gravity center within the region based on a result of detection by the motion detection unit, a region evaluation unit calculating an evaluation value within the region and selecting a region having a smallest evaluation value based on the calculation result, a holding operation recognition state machine recognizing a holding operation by the object within the region selected by the region evaluation unit, and a gravity center trace recognition unit recognizing gesture of the object based on the trace of the gravity center within the region selected by the region evaluation unit.  
      According to the invention disclosed in Japanese Patent Laying-Open No. 2001-307107, as gestures or hand gestures can be recognized with high accuracy, interface between a person and a computer can be provided through gestures.  
      The invention disclosed in Japanese Patent Laying-Open No. 06-153017, however, suffers difficulty in achieving a smaller size of the remote control apparatus. As can clearly be seen from  FIG. 11 , the invention disclosed in Japanese Patent Laying-Open No. 06-153017 requires a monitor even for controlled equipment that originally does not require the monitor, such as an air conditioner. This is because the user has his/her own body displayed on the monitor. Presence of the monitor impedes reduction in size of the remote control apparatus, which makes it difficult to make smaller the remote control apparatus. In addition, according to the invention disclosed in Japanese Patent Laying-Open No. 06-153017, if the user makes a movement irrelevant to manipulation, malfunction is likely. If the whole body of the user is displayed on the monitor, tendency to malfunction is particularly noticeable.  
      The invention disclosed in Japanese Patent Laying-Open No. 2001-307107 also suffers a disadvantage that malfunction is likely, because the video camera is distant from the human body.  
     SUMMARY OF THE INVENTION  
      The present invention was made to solve the above-described problems. An object of the present invention is to provide an equipment control apparatus readily made smaller in size and less likely to malfunction, a remote controller, equipment, an equipment control method, and an equipment control program product.  
      In order to achieve the object above, according to one aspect of the present invention, an equipment control apparatus is an equipment control apparatus for controlling equipment. The equipment control apparatus includes an image pick-up unit picking up an image, a storage unit, a processor, and an output unit. The storage unit stores image data and a program. The image data represents the image picked up by the image pick-up unit. The processor, upon receiving an instruction from the program, counts the number of pixels representing a color of skin of a human body among pixels in a part of the image, to output the counted number as a specific number based on the image data, and generates at least one control signal for controlling the equipment if the number exceeds a specific number threshold value. The output unit outputs the control signal.  
      In addition, desirably, a plurality of areas of the image correspond to different control signals respectively, and the processor described above counts the number of pixels representing the color of skin in each of the areas, and selectively generates one of the control signals corresponding to the area where the counted number exceeds a corresponding specific number threshold value.  
      Alternatively, desirably, the processor described above generates the control signal of a type corresponding to each of the areas of which specific number exceeds the specific number threshold value.  
      Alternatively, desirably, the processor described above counts the specific number for each of the plurality of areas obtained by dividing the image into two.  
      Alternatively, desirably, the processor described above counts the specific number for each of the plurality of areas adjacent to each other, obtained by dividing the image into four.  
      In addition, desirably, the storage unit described above stores the specific number in addition to the image data and the program. Moreover, desirably, the processor, upon receiving the instruction from the program, further determines whether excess number exceeds an excess number threshold value. The excess number indicates the number of times that the specific number exceeds the specific number threshold value. The excess number threshold value represents a threshold value for the excess number. Moreover, desirably, the processor generates the control signal if the excess number exceeds the excess number threshold value and if the specific number exceeds the specific number threshold value.  
      In addition, desirably, the storage unit described above stores the specific number in addition to the image data and the program. Moreover, desirably, the processor, upon receiving the instruction from the program, further determines whether excess number is equal to or smaller than an excess number threshold value. The excess number indicates the number of times that the specific number exceeds the specific number threshold value. The excess number threshold value represents a threshold value for the excess number. Moreover, desirably, the processor generates the control signal if the excess number is equal to or smaller than the excess number threshold value and if the specific number exceeds the specific number threshold value.  
      In addition, desirably, the storage unit described above stores the specific number in addition to the image data and the program. Moreover, desirably, the processor, upon receiving the instruction from the program, further determines whether excess number is within a range defined by two threshold values for the excess number. The excess number indicates the number of times that the specific number exceeds the specific number threshold value. Further, desirably, the processor generates the control signal if the excess number is within the range defined by the two threshold values and if the specific number exceeds the specific number threshold value.  
      In addition, desirably, the image pick-up unit described above includes an image pick-up unit implemented as a color camera.  
      In addition, desirably, the image pick-up unit described above includes an image pick-up unit using a lens different from a wide-angle lens.  
      In addition, desirably, the image pick-up unit described above includes an image pick-up unit picking up an infrared image.  
      In addition, desirably, the processor described above counts the specific number for a plurality of areas. Moreover, desirably, the storage unit stores, in addition to the image data and the program, the specific number for each of the plurality of areas. Moreover, if a largest specific number out of the specific numbers stored in the storage unit exceeds the specific number threshold value, the processor desirably generates the control signal of a type corresponding to the area having the largest specific number.  
      Alternatively, desirably, the processor described above counts the specific number for a plurality of areas. Moreover, desirably, the storage unit stores, in addition to the image data and the program, the specific number for each of the plurality of areas in association with a group of areas. Moreover, if at least one of largest specific numbers in each group of areas stored in the storage unit exceeds the specific number threshold value, the processor desirably generates the control signal of a type corresponding to the area of which largest specific number exceeds the specific number threshold value.  
      In addition, desirably, the image data stored in the storage unit described above includes image data of a plurality of images picked up by the image pick-up unit, different in a time point of image pick-up. Moreover, desirably, the processor, upon receiving the instruction from the program, further calculates a value representing difference in color of the pixels at corresponding positions in the plurality of images. Moreover, the processor desirably determines whether the value representing difference in color exceeds a threshold value for the value representing difference in color. Moreover, desirably, the storage unit stores, in addition to the image data and the program, a value corresponding to whether the value representing difference in color exceeds the threshold value for the value representing difference in color. Moreover, desirably, the specific number indicates the number of pixels corresponding to the value representing difference in color exceeding the threshold value for the value representing difference in color, and representing the color of skin of the human body among the pixels forming a most recent image among the plurality of images.  
      In addition, desirably, the image data stored in the storage unit described above includes image data of a plurality of images picked up by the image pick-up unit, different in a time point of image pick-up. Moreover, desirably, the processor, upon receiving the instruction from the program, further calculates a value representing difference in color of the pixels at corresponding positions in the plurality of images. Moreover, the processor desirably further determines whether the value representing difference in color is equal to or smaller than a threshold value for the value representing difference in color. Moreover, desirably, the storage unit stores, in addition to the image data and the program, a value corresponding to whether the value representing difference in color is equal to or smaller than the threshold value for the value representing difference in color. Moreover, desirably, the specific number indicates the number of pixels corresponding to the value representing difference in color equal to or smaller than the threshold value for the value representing difference in color, and representing the color of skin of the human body among the pixels forming a most recent image among the plurality of images.  
      In addition, desirably, the equipment control apparatus described above further includes a housing.  
      According to another aspect of the present invention, a remote controller is a remote controller for controlling equipment. The remote controller includes an image pick-up unit picking up an image, a storage unit, a processor, and a transmission device. The storage unit stores image data, a program and information for controlling the equipment. The image data represents an image picked up by the image pick-up unit. The processor executes the following processing, upon receiving an instruction from the program. The processing includes the processing for counting the specific number and the processing for generating a control signal. The processing for counting the specific number is the processing for counting the specific number for an area based on the image data. The area represents at least a part of the image. The specific number indicates the number of pixels representing a color of skin of a human body among pixels forming the image. The processing for generating a control signal is the processing for generating a control signal for controlling the equipment based on the information for controlling the equipment if the specific number exceeds a specific number threshold value. The specific number threshold value is a threshold value for the specific number. The transmission device transmits the control signal.  
      According to another aspect of the present invention, equipment includes an image pick-up unit picking up an image, a storage unit, a processor, and a device operating in response to a control signal. The storage unit stores image data and a program. The image data represents an image picked up by the image pick-up unit. The processor executes the following processing, upon receiving an instruction from the program. The processing includes the processing for counting the specific number and the processing for generating a control signal. The processing for counting the specific number is the processing for counting the specific number for an area based on the image data. The area represents at least a part of the image. The specific number indicates the number of pixels representing a color of skin of a human body among pixels forming the image. The processing for generating a control signal is the processing for generating a control signal if the specific number exceeds a specific number threshold value. The specific number threshold value represents a threshold value for the specific number.  
      According to another aspect of the present invention, an equipment control method is an equipment control method for controlling equipment. The equipment control method includes image pick-up step, the step of determining whether a color is the color of skin of a human body, the step of counting the specific number, and the step of outputting a control signal. The image pick-up step is the step of picking up an image. The step of determining whether a color is the color of skin of a human body is the step of determining whether a color of a pixel forming the image picked up in the image pick-up step is a color of skin of a human body. The step of counting the specific number is the step of counting the specific number for an area. The area represents at least a part of the image. The specific number indicates the number of pixels representing a color of skin of a human body among pixels forming the image. The step of outputting a control signal is the step of outputting a control signal for controlling the equipment if the specific number exceeds a specific number threshold value. The specific number threshold value represents a threshold value for the specific number.  
      According to another aspect of the present invention, an equipment control program product is an equipment control program product for controlling equipment. The equipment control program product causes a computer to execute the steps of controlling an image pick-up unit, determining whether a color is the color of skin of a human body, counting the specific number, and outputting a control signal. The step of controlling an image pick-up unit is the step of controlling an image pick-up unit so as to pick up an image. The step of determining whether a color is the color of skin of a human body is the step of determining whether a color of a pixel forming the image picked up in the controlling step is a color of skin of a human body. The step of counting the specific number is the step of counting the specific number for an area. The area represents at least a part of the image. The specific number indicates the number of pixels representing a color of skin of a human body among pixels forming the image. The step of outputting a control signal is the step of outputting a control signal for controlling the equipment if the specific number exceeds a specific number threshold value. The specific number threshold value represents a threshold value for the specific number.  
      The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a conceptual diagram illustrating a configuration of an equipment control apparatus and a method of using the same according to a first embodiment of the present invention.  
       FIG. 2  is a control block diagram of the equipment control apparatus according to the first embodiment of the present invention.  
       FIG. 3  is a flowchart illustrating a control procedure for control signal output processing according to the first embodiment of the present invention.  
       FIG. 4  illustrates arrangement of divisional areas according to the first embodiment of the present invention.  
       FIG. 5  illustrates appearance of a remote controller according to a variation of the first embodiment of the present invention.  
       FIG. 6  is a conceptual diagram illustrating a method of using the remote controller according to the variation of the first embodiment of the present invention.  
       FIG. 7  is a flowchart illustrating a control procedure for control signal output processing according to a second embodiment of the present invention.  
       FIG. 8  is a flowchart illustrating a control procedure for control signal output processing according to a third embodiment of the present invention.  
       FIG. 9  is a flowchart illustrating a control procedure for control signal output processing according to a fourth embodiment of the present invention.  
       FIG. 10  illustrates an exemplary image of a human body displayed on a monitor of a remote control apparatus according to a conventional example.  
       FIG. 11  illustrates a configuration of the remote control apparatus according to the conventional example. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
      An embodiment of the present invention will be described hereinafter with reference to the drawings. In the description, the same elements have the same reference characters allotted. Their label and function are also identical. Therefore, detailed description thereof will not be repeated.  
     First Embodiment  
      An equipment control apparatus according to a first embodiment of the present invention will be described hereinafter.  
       FIG. 1  is a conceptual diagram illustrating a configuration of the equipment control apparatus and a method of using the same according to the present embodiment.  
       FIG. 2  is a control block diagram of the equipment control apparatus according to the present embodiment. Referring to  FIGS. 1 and 2 , the equipment control apparatus includes a video camera  102  and a main apparatus  103 . Video camera  102  is an apparatus that picks up an image of a hand or the like of a user  101 . In the present embodiment, video camera  102  is implemented as a color camera equipped with a unit for image pick-up and employing a lens different from a wide-angle lens. Whether a lens may be mounted on video camera  102  or not is determined based on whether the entire image pick-up area is covered by a hand or the like when user  101  holds the hand or the like at a position several centimeters forward of the lens. In the present embodiment, a lens having an angle of view of 60° is used as the “lens different from a wide-angle lens.” Main apparatus  103  is an apparatus processing the image picked up by video camera  102 . A signal output after main apparatus  103  processes the image is output to a television receiver  104 . In the present embodiment, each of video camera  102  and main apparatus  103  is covered with a housing. These housings allow the equipment control apparatus according to the present embodiment to be embedded in a wall of a building. More specifically, these housings are housings having a heat insulating material along an inner side of a steel plate.  
      Main apparatus  103  includes a CPU  110 , a memory  112 , an image processing unit  114 , a terminal  116 , and a reader  118 . CPU  110  is a device performing various operations based on a signal processed by image processing unit  114 . CPU  110  thus serves as a device attaining various functions. CPU  110  also serves as a device generating a control signal. CPU  110  includes a buffer storing image data of the image picked up by video camera  102 , a counter counting the number, and a timer measuring elapsed time. Memory  112  is a device storing information. In the present embodiment, memory  112  includes a plurality of areas. Each of the plurality of areas in memory  112  stores different information. Image processing unit  114  is a device processing the image picked up by video camera  102 . As a result of processing by image processing unit  114 , a signal output from video camera  102  is converted to a signal that CPU  110  can make use of Terminal  116  is a terminal outputting the control signal generated by CPU  110 . Reader  118  reads a program for implementing the equipment control apparatus according to the present embodiment from a recording medium. In the present embodiment, the recording medium from which reader  118  reads the program is implemented by a CD-ROM (Compact Disk Read Only Memory)  130 .  
      The equipment control apparatus according to the present embodiment is implemented by computer hardware including the apparatus for image pick-up and software executed by CPU  110 . The “computer hardware including the apparatus for image pick-up” includes computer hardware on which video camera  102  is mounted, in addition to computer hardware to which video camera  102  is connected. Examples of the computer hardware to which video camera  102  is connected include a PDA (Personal Digital Assistant) on which a camera is mounted, and the like. In general, such software is distributed with being stored in a recording medium such as CD-ROM  130 , read from the recording medium by reader  118  or the like, and once stored in memory  112 . In addition, the software is executed by CPU  110  described above. The computer hardware itself described above is common. Therefore, the most essential part of the present invention resides in the software recorded in a recording medium such as CD-ROM  130 . Here, as an operation of the computer itself is well known, detailed description thereof will not be repeated.  
      Referring to  FIG. 3 , the program executed in the equipment control apparatus according to the present embodiment carries out the following control for output of a control signal.  
      In step  300  (hereinafter, step is abbreviated as S), video camera  102  picks up an image. Video camera  102  outputs image data of the picked up image as a signal. Image processing unit  114  reads the image data of the image picked up by video camera  102 . The read image data is image data of one screen. Image processing unit  114  converts the read signal to a signal that CPU  110  can make use of.  
      In S 302 , CPU  110  determines whether each pixel is a pixel of flesh-color or not. Here, “each pixel” refers to a pixel forming the image picked up by video camera  102 . The “pixel of flesh-color” refers to a pixel having a color of skin of the human body. Whether the color of the pixel is the color of skin of the human body is determined based on whether a value representing the color of the pixel is within a range determined in advance by a manufacturer or a user of the equipment control apparatus of the present embodiment. In the present embodiment, the range is defined by an empirical value determined in accordance with an illumination condition, an ethnic group to which the user belongs, or the like. If data of the color of each pixel is the data that can be obtained based on YCrCb representation system, CPU  110  can determine, in a stable manner, whether or not data of the color of each pixel represents the color of the skin, regardless of luminance. When whether or not each pixel is the pixel of flesh-color is determined, CPU  110  causes memory  112  to store a value. The area of memory  112  storing the value is the area for storing the pixel of flesh-color. The value stored in memory  112  is a value corresponding to whether the pixel is the pixel of flesh-color or not. In the present embodiment, it is assumed that the value “1” is stored in memory  112  for the pixel of flesh-color and “0” is stored for the pixel otherwise.  
      In S 304 , CPU  110  refers to the value stored in memory  112  in S 302 . When the value is referred to, CPU  110  counts the specific number. Here, the “specific number” refers to the number of pixels that are pixels of flesh-color. In the present embodiment, CPU  110  counts the specific number for each divisional area. As the specific number is counted for each divisional area, CPU  110  counts the specific number for an area representing at least a part of the image. When the specific number is counted, memory  112  stores the specific number in association with the divisional area. The area of memory  112  storing the specific number is the area for storing the specific number.  
      The divisional area will be described with reference to  FIG. 4 .  FIG. 4  illustrates arrangement of the divisional areas according to the present embodiment. In the present embodiment, the divisional areas include a first divisional area  201 , a second divisional area  202 , a third divisional area  203 , and a fourth divisional area  204 . As can clearly be seen from  FIG. 4 , in the present embodiment, each of first to fourth divisional areas  201  to  204  represents a part of the image. In addition, first to fourth divisional areas  201  to  204  according to the present embodiment are a plurality of areas adjacent to each other, obtained by dividing the image into four. CPU  110  thus counts the specific number for each of the plurality of areas adjacent to each other, obtained by dividing the image into four.  
      In S 306 , CPU  110  selects an area having the largest specific number from among the divisional areas, based on the specific number stored in memory  112 .  
      In S 308 , CPU  110  determines whether the specific number of the area selected by the CPU itself exceeds a predetermined threshold value. If it is determined that the specific number exceeds the predetermined threshold value (YES in S 308 ), the process proceeds to S 310 . Otherwise (NO in S 308 ), the process proceeds to S 300 . In S 310 , terminal  116  outputs a control signal of a type corresponding to the divisional area selected in S 306 . CPU  110  generates the control signal based on prescribed information for controlling the equipment. The “prescribed information for controlling the equipment” has been stored in memory  112 .  
      An operation of the equipment control apparatus based on the configuration and the flowchart as above will now be described.  
      User  101  puts out his/her hand toward video camera  102 . Video camera  102  picks up the image of the hand of user  101 . Video camera  102  outputs the picked-up image to image processing unit  114 . Image processing unit  114  reads the image data of the image picked up by video camera  102  (S 300 ). When the image data is read, CPU  110  determines whether each pixel is the pixel of flesh-color or not. When determination as to whether or not the pixel is the pixel of flesh-color is made, CPU  110  causes memory  112  to store the value in accordance with whether the pixel is the pixel of flesh-color (S 302 ).  
      When the value is stored, CPU  110  counts the specific number for each divisional area (S 304 ). In  FIG. 4 , the hand of user  101  overlaps most with fourth divisional area  204 . The hand of user  101  slightly overlaps also with first to third divisional areas  201  to  203 .  
      When the specific number is counted, CPU  110  selects the divisional area having the largest specific number (S 306 ). As is clear from the description above and  FIG. 4 , fourth divisional area  204  has the largest specific number. CPU  110  selects fourth divisional area  204  as the area having the largest specific number.  
      When the area is selected, CPU  110  determines whether the specific number of fourth divisional area  204  exceeds a predetermined threshold value TH (S 308 ). Here, if it is assumed that the specific number of fourth divisional area  204  exceeds threshold value TH (YES in S 308 ), terminal  116  outputs the control signal of a type corresponding to fourth divisional area  204  (S 310 ). In the present embodiment, it is assumed that the control signal corresponding to fourth divisional area  204  is the signal for turning up the volume of television receiver  104 . The volume of television receiver  104  is thus turned up.  
      As described above, the equipment control apparatus according to the present embodiment outputs the control signal as a result of the user&#39;s movement of holding his/her hand over the video camera. When a quarter of the image pick-up region of the video camera is covered, the video camera outputs the control signal corresponding to the covered region. Accordingly, the equipment control apparatus according to the present embodiment does not respond unless the user puts out his/her hand or the like immediately in front of the video camera. Malfunction does not occur unless the hand or the like is put out immediately in front of the video camera. Malfunction does not occur simply by slightly covering the video camera. The equipment control apparatus according to the present embodiment can output the control signal without checking whether the hand covers the divisional area on a monitor or the like. This is because the equipment control apparatus according to the present embodiment does not respond or malfunction unless the hand or the like is put out immediately in front of the video camera and the image pick-up area is sufficiently covered. The reason why the equipment control apparatus does not respond or malfunction is that the image pick-up areas are implemented by the plurality of areas adjacent to each other, obtained by dividing the image. Consequently, as the monitor is not necessary, the equipment control apparatus readily made smaller in size and less likely to malfunction can be provided.  
      In addition, the equipment control apparatus according to the present embodiment can accurately determine whether the color of the pixel is the color of skin of a human, by using the color camera.  
      In addition, the video camera of the equipment control apparatus according to the present embodiment employs the lens different from the wide-angle lens. As the lens different from the wide-angle lens is employed, the user can readily cover an arbitrary area of the image by holding his/her hand or the like in front of the lens. As an arbitrary area of the image is readily covered, occurrence of malfunction can be suppressed. Malfunction can thus be less likely than in an example where the wide-angle lens is used. When the wide-angle lens is used, it is difficult to cover an arbitrary area of the image even if the hand or the like is held in front of the lens.  
      Note that, as a variation, the equipment control apparatus according to the present embodiment may be implemented as equipment. Examples of such equipment include a remote controller, a television receiver, a computer, a car navigation system, a pinball-type game machine, a portable phone, or a fan.  FIG. 5  illustrates appearance of the equipment control apparatus implemented as a remote controller  120 . Recently, a camera has been incorporated in a portable phone, and a camera unit has been reduced in size. The equipment control apparatus according to the present embodiment can be implemented sufficiently as a small apparatus such as a remote controller. The devices other than terminal  116  shown in  FIG. 2  are included in remote controller  120 . Remote controller  120  includes a transmission device  122  instead of terminal  116 . Transmission device  122  is a device transmitting a control signal of a type corresponding to an area, using infrared ray or through a wire or the like, if the specific number exceeds a first threshold value. When remote controller  120  is manipulated in  FIG. 5 , user  101  holds his/her hand in front of video camera  102  provided on a surface of remote controller  120  and moves the hand.  FIG. 6  illustrates a method of using remote controller  120 . A person, for example, an elderly person who has difficulty in pressing a small button, can transmit the control signal solely by moving his/her hand around remote controller  120 . Here, transmission device  122  may be a device connected to terminal  116 . If transmission device  122  is connected to terminal  116 , transmission device  122  is implemented as a device that operates in response to a control signal output from terminal  116 .  
      In addition, as a variation, the divisional area for which the specific number is counted in S 304  or the like may be an area different from those shown in  FIG. 4 . For example, first divisional area  201  and second divisional area  202  may serve as one area. In this case, third divisional area  203  and fourth divisional area  204  may serve as one area. Instead of first divisional area  201  and second divisional area  202  forming one area, first divisional area  201  and third divisional area  203  may serve as one area. In this case, second divisional area  202  and fourth divisional area  204  may serve as one area. The divisional areas are thus implemented as a plurality of areas adjacent to each other, obtained by dividing the image into two. If the divisional areas are implemented as such, CPU  110  counts the specific number for each of the plurality of areas adjacent to each other, obtained by dividing the image into two. The image pick-up area covered by user  101  in order to output the control signal is thus greater than in the case of division of the image into four. As the image pick-up area is greater, malfunction is less likely and manipulation is facilitated. Consequently, as compared with the case in which the control signal is output by covering the area obtained by dividing the image into four, malfunction is less likely and manipulation can be facilitated.  
      In addition, as a variation, the divisional area for which the specific number is counted in S 304  or the like may be an area obtained by diagonally dividing the image. In the case that the divisional area is implemented as such as well, CPU  110  counts the specific number for each of the plurality of areas adjacent to each other, obtained by dividing the image into two. Alternatively, the image may be divided into any number of areas other than two or four, which means that the divisional areas may be a plurality of areas adjacent to each other, obtained by dividing the image into several areas. If 9 or more areas are obtained by dividing the image, however, it is less effective than in the case where two to four areas are obtained, because manipulation becomes difficult. Alternatively, instead of the divisional areas, the entire image may serve as one area. Alternatively, a part of the image may serve as an area for which the specific number is counted.  
      In addition, as a variation, video camera  102  may be implemented by a camera capable of picking up an infrared image. If a camera capable of picking up an infrared image is used, CPU  110  no longer needs to determine whether or not the color of the pixel is the flesh-color. This is because the camera capable of picking up an infrared image responds solely to the infrared ray emitted from a human body or other animals and because CPU  110  can use the signal output from that camera as it is to determine whether the hand or the like of user  101  covers a certain area. The equipment control apparatus according to the present embodiment may be implemented by a camera picking up an image of a human body by using static electricity, ultrasound or electromagnetic wave emitted from the human body, instead of video camera  102 . A monochrome camera may be used only when difference in luminance between the hand or the like and the surroundings thereof can be detected.  
      In addition, as a variation, the recording medium from which reader  118  reads the program is not limited to the CD-ROM. Examples of the recording medium other than the CD-ROM include an FD (Flexible Disk), a flash memory, and a hard disk.  
      In addition, as a variation, the equipment control apparatus according to the present embodiment may be embedded in a wall of a building.  
     Second Embodiment  
      An equipment control apparatus according to a second embodiment of the present invention will be described hereinafter.  
      The equipment control apparatus according to the present embodiment is the same as that in the first embodiment, and the function thereof is also the same. Therefore, detailed description thereof will not be repeated.  
      Referring to  FIG. 7 , the program executed in the equipment control apparatus carries out the following control for output of a control signal. It is noted that the processing in the flowchart in  FIG. 7  that has been shown in  FIG. 3  described previously is given the same step number, and the processing is also the same. Therefore, detailed description thereof will not be repeated.  
      In S 320 , CPU  110  sets the value of the counter to “0”.  
      In S 322 , CPU  110  determines whether the specific number of the area having the largest specific number exceeds a predetermined threshold value. If it is determined that the predetermined threshold value is exceeded (YES in S 322 ), the process proceeds to S 324 . Otherwise (NO in S 322 ), the process proceeds to S 300 . In S 324 , CPU  110  increments the value of the counter by “1”.  
      In S 326 , CPU  110  determines whether the value of the counter exceeds a prescribed threshold value. If it is determined that the value of the counter exceeds the prescribed threshold value (YES in S 326 ), the process proceeds to S 310 . Otherwise (NO in S 326 ), the process proceeds to S 300 .  
      An operation of the equipment control apparatus based on the configuration and the flowchart as above will now be described.  
      CPU  110  sets the value of the counter to “0” (S 320 ). When the value of the counter is set to “0”, after the processing in S 300  to S 306 , CPU  110  determines whether the specific number of the area having the largest specific number exceeds the predetermined threshold value (S 322 ). Here, if it is assumed that the predetermined threshold value is exceeded (YES in S 322 ), CPU  110  increments the value of the counter by “0” (S 324 ). When the value of the counter is incremented by “1”, CPU  110  counts the excess number which indicates the number of times that the specific number exceeds the first threshold value. When the value of the counter is incremented, CPU  110  determines whether the value of the counter, that is, the excess number, exceeds the predetermined threshold value (S 326 ). If it is assumed that the value of the counter initially does not exceed the threshold value (NO in S 326 ), the processing in S 300  to S 326  is repeated. Thereafter, if the value of the counter exceeds the threshold value (YES in S 326 ), terminal  116  outputs the control signal of a type corresponding to the divisional area (S 310 ). Terminal  116  thus outputs the control signal of a type corresponding to the divisional area if the excess number is equal to or greater than the threshold value and if the specific number exceeds the threshold value.  
      As described above, the equipment control apparatus according to the present embodiment outputs the control signal if the user keeps holding his/her hand for a certain predetermined period or longer, not if the user momentarily holds his/her hand. Reliability of the equipment control apparatus is thus improved. Consequently, the equipment control apparatus readily made smaller in size, less likely to malfunction, and attaining high reliability can be provided.  
      Note that, as a variation, CPU  110  may determine in S 326  whether the excess number is equal to or smaller than the predetermined threshold value. Here, terminal  116  may output the control signal of a type corresponding to the divisional area if the excess number is equal to or smaller than the threshold value and if the specific number exceeds the threshold value. Thus, if user  101  places his/her hand for too long a time period, the equipment control apparatus does not respond. Reliability of the equipment control apparatus is improved. Consequently, the equipment control apparatus readily made smaller in size, less likely to malfunction, and attaining high reliability can be provided.  
      In addition, as a variation, CPU  110  may determine in S 326  whether the excess number is within a range from a certain threshold value to another threshold value. Here, terminal  116  may output the control signal of a type corresponding to the divisional area if the excess number is within that range and if the specific number exceeds the threshold value. Thus, unless a time period during which user  101  places his/her hand is within a certain range, for example, a range from 5 to 8 seconds, the equipment control apparatus does not respond. Reliability of the equipment control apparatus is improved. As to reliability in various applications, reliability in terms of security, for example, in a case of a key of a safe or an immobilizer of a vehicle, is particularly improved. Consequently, the equipment control apparatus readily made smaller in size, less likely to malfunction, and attaining high reliability in terms of security can be provided.  
     Third Embodiment  
      An equipment control apparatus according to a third embodiment of the present invention will be described hereinafter.  
      The hardware configuration of the equipment control apparatus according to the present embodiment is the same as that in the first embodiment described previously, and the function thereof is also the same. Therefore, detailed description thereof will not be repeated.  
      Referring to  FIG. 8 , the program executed in the equipment control apparatus carries out the following control for output of a control signal. It is noted that the processing in the flowchart in  FIG. 8  that has been shown in  FIG. 3  described previously is given the same step number, and the processing is also the same. Therefore, detailed description thereof will not be repeated.  
      In S 330 , CPU  110  causes memory  112  to store image data read from video camera  102 , in a certain area thereof. By storing the image data, memory  112  stores a plurality of images. The plurality of images that are stored are images picked up by video camera  102 , different in a time point of image pick-up.  
      In S 332 , CPU  110  finds a difference between image data stored in memory  112  in the past and image data stored in S 330 . Here, to “find a difference” refers to calculation of a difference between values representing the color of each pixel correspondingly arranged, among the pixels forming the image. CPU  110  thus calculates the value representing the difference in color, of the pixels at corresponding positions in a plurality of images. When the difference is found, CPU  110  determines whether a differential value which is a value representing the difference in color exceeds a certain threshold value. When determination as to whether or not the threshold value is exceeded is made, CPU  110  causes memory  112  to store the value corresponding to whether the differential value exceeds the threshold value. That value is stored in association with the pixel forming the most recent image, among the images stored in memory  112 . In the present embodiment, “1” is associated with the pixel of which differential value exceeds the threshold value, and “0” is associated with the pixel of which differential value does not exceed the threshold value.  
      In S 334 , CPU  110  determines whether the color of the pixel associated with “1” in S 332  is the color of skin of the human body. As described above, the pixel associated with “1” in S 332  is the pixel of which differential value exceeds the threshold value. The pixel associated with “1” in S 332  is also the pixel forming the most recent image among the images stored in memory  112 . When determination as to whether the color of the pixel represents the color of skin of the human body is made, memory  112  stores a value separately from the value stored in S 332 . Among the values to be stored, the value “1” is associated with the pixel of the flesh-color.  
      An operation of the equipment control apparatus based on the configuration and the flowchart as above will now be described.  
      Memory  112  stores the image data picked up by video camera  102  (S 330 ). When the image data is stored, CPU  110  finds the difference. When the difference is found, the value is stored in memory  112  based on whether the differential value exceeds the threshold value (S 332 ). When the value is stored, CPU  110  causes memory  112  to store the value such that “1” is associated with the pixel of flesh-color, among the pixels for which “1” has been stored (S 334 ).  
      As described above, the equipment control apparatus according to the present embodiment causes output of the control signal, as a result of such a movement as waving a hand in a certain divisional area instead of covering the same with hand. The control signal is thus output if a certain movement is detected. Consequently, the equipment control apparatus readily made smaller in size, less likely to malfunction, and capable of detecting a movement can be provided.  
      Note that, as a variation, CPU  110  may determine in S 332  whether the differential value is equal to or smaller than a certain threshold value. Here, when determination as to whether the differential value is equal to or smaller than the threshold value is made, CPU  110  causes memory  112  to store the value corresponding to whether the differential value is equal to or smaller than the threshold value. The value is stored in association with the pixel forming the most recent image among the images stored in memory  112 . In this case as well, “1” is associated with the pixel of which differential value exceeds the threshold value, and “0” is associated with the pixel of which differential value does not exceed the threshold value. Thus, CPU  10  determines in S 334  whether the color of the pixel of which differential value is equal to or smaller than the threshold value represents the color of skin of the human body. When determination as to whether the color of the pixel of which differential value is equal to or smaller than the threshold value is the color of skin of the human body is made, the control signal is output if the hand stays in a certain divisional area, not if the hand is placed in that area merely for a short period of time.  
     Fourth Embodiment  
      An equipment control apparatus according to a fourth embodiment of the present invention will be described hereinafter.  
      The hardware configuration of the equipment control apparatus according to the present embodiment is the same as that in the first embodiment described previously, and the function thereof is also the same. Therefore, detailed description thereof will not be repeated.  
      Referring to  FIG. 9 , the program executed in the equipment control apparatus carries out the following control for output of a control signal.  
      It is noted that the processing in the flowchart in  FIG. 9  that has been shown in  FIG. 3  described previously is given the same step number, and the processing is also the same. Therefore, detailed description thereof will not be repeated.  
      In S 340 , CPU  110  selects the area having the largest specific number among the divisional areas, for each of two “groups of areas.” 
      In S 342 , CPU  110  determines whether the specific number of the area having the largest specific number is equal to or smaller than a predetermined threshold value in both of the two “groups of the areas.” CPU  10  thus determines whether the specific number of the area having the largest specific number exceeds the threshold value for each group of the areas. If it is determined that the specific number is equal to or smaller than the predetermined threshold value (YES in S 342 ), the process proceeds to S 300 . Otherwise (NO in S 342 ), the process proceeds to S 344 .  
      In S 344 , terminal  116  outputs the control signal corresponding to the area of which specific number exceeds the threshold value in the two “groups of areas” if the specific number of the area having the largest specific number exceeds the predetermined threshold value. It is CPU  110  that generates the control signal to be output. Terminal  116  thus outputs the control signal of a type corresponding to each area of which specific number exceeds the threshold value.  
      An operation of the equipment control apparatus based on the configuration and the flowchart as above will now be described.  
      When the specific number is counted, CPU  110  selects the area having the largest specific number among the divisional areas, for each of the two “groups of areas.” In the present embodiment, it is assumed that first divisional area  201  and third divisional area  203  form one group, and second divisional area  202  and fourth divisional area  204  form one group. CPU  110  thus selects third divisional area  203 , in the group consisting of first divisional area  201  and third divisional area  203 . CPU  10  selects fourth divisional area  204 , in the group consisting of second divisional area  202  and fourth divisional area  204  (S 340 ). When the area is selected, CPU  110  determines whether the specific number of the area having the largest specific number is equal to or smaller than a predetermined threshold value TH in both of the two “groups of areas” (S 342 ). Here, if it is assumed that the specific number of each of first divisional area  201  and fourth divisional area  204  exceeds predetermined threshold value TH (NO in S 342 ), terminal  116  outputs the control signals corresponding to first divisional area  201  and fourth divisional area  204  respectively (S 344 ).  
      As described above, the equipment control apparatus according to the present embodiment determines whether the user&#39;s hand or the like covers the area for each group of the areas, and outputs the control signal in accordance with the covered area if the user&#39;s hand or the like covers the area. A plurality of pieces of equipment can thus simultaneously operate. Consequently, the equipment control apparatus readily made smaller in size, less likely to malfunction, and capable of simultaneously performing a plurality of operations can be provided.  
      Note that, as a variation, in S 344 , terminal  116  may output the control signal corresponding to any area of which specific number exceeds the threshold value, in the two “groups of areas.” Terminal  116  thus outputs the control signal of a type corresponding to any area of which specific number exceeds the first threshold value.  
      Although the present invention has been described and illustrated in detail, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, the spirit and scope of the present invention being limited only by the terms of the appended claims.