Abstract:
An image display apparatus has an image-processing unit, an image display unit, and a jump-instructing unit. The image-processing unit generates data representing images having frame numbers. The image display unit displays the images represented by the data. The jump-instructing unit generates an instruction to cause the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed by the image display unit. In response to the instruction, the image-processing unit generates data representing a multi-image consisting of images intervening between the image being displayed and the image whose serial number differs by the predetermined number. The image display unit first displays the multi-image and then the image whose serial number differs by the predetermined number.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from prior Japanese Patent Application No. 2003-065140, filed Mar. 11, 2003, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image display apparatus, a camera having an image display apparatus, a method of controlling an image display apparatus, and a recording medium storing a program for controlling an image display apparatus. More particularly, the invention relates to an image display apparatus that facilitates retrieval of image data, and to a digital camera that has such an image display apparatus. 
     2. Description of the Related Art 
     The recording medium incorporated in digital cameras can store data representing many images. The recording medium may be, for example, a 64-MB memory that can store data representing 100 or more images. The current trend is to incorporate into digital cameras a recording media of a greater storage capacity. The more image data items the medium stores, the more efficiently they must be retrieved from the medium to enable the user to see the images he or she wants. 
     Jpn. Pat. Appln. KOKAI Publication No. 11-146326 discloses a method of retrieving image data. In this method, the buttons provided on an image display unit may be pushed to change the speed at which the image display unit reproduces and displays images one after another. 
     Jpn. Pat. Appln. KOKAI Publication No. 10-243331 discloses an image display apparatus for use with digital cameras, which is designed to facilitate retrieval of image data items. This apparatus has an LCD that can display four images or nine images at a time. Namely, the LCD performs so-called multi-image displaying. Seeing these images displayed, the user may select at least one image displayed, thus retrieving the data items representing the image selected. 
     BRIEF SUMMARY OF THE INVENTION 
     An object of this invention is provide an image display apparatus that can enables the user to retrieve image data items from a recording medium with high efficiency, a camera having such an image display apparatus, a method of controlling such an image display apparatus, and a recording medium storing programs for controlling such an image display apparatus. 
     According to a first aspect of the invention, there is provided an image display apparatus. The apparatus comprises: an image-processing unit which generates data representing images to be displayed; an image display unit which displays images represented by the data generated by the image-processing unit; a display control unit which controls the image-processing unit and the image display unit; and a jump-instructing unit which instruct the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed by the image display unit. In response to an instruction from the jump-instructing unit, the display control unit causes the image-processing unit to generate data representing a multi-image consisting of images intervening between the image being displayed and the image whose serial number differs by the predetermined number. 
     According to a second aspect of the invention, there is provided an image display apparatus. This apparatus comprises: an image display unit which displays images; a display control unit which controls the image display unit; and a jump-instructing unit which instructs the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed by the image display unit. In response to an instruction from the jump-instructing unit, the display control unit causes the image display unit to display the intervening images sequentially, each for a different period, and then to display the image whose serial number differs by the predetermined number. 
     According to a third aspect of the invention, there is provided a method of controlling an image display apparatus, in which the image display unit of the apparatus displays images in the order of the serial numbers of the images, in response to an instruction. The method comprises the steps of: instructing the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed; generating data representing a multi-image consisting of images intervening between the image being displayed and the image whose serial number differs by the predetermined number; and displaying the intervening images and then to display the image whose serial number differs by the predetermined number. 
     According to a fourth aspect of this invention, there is provided a method of controlling an image display apparatus. In this method, the image display unit of the apparatus displays images in the order of the serial numbers of the images. This method comprises: the steps of: instructing the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed; and causing the image display unit to display images intervening between the image being displayed and the image whose serial number differs by the predetermined number, each for a different period, and then to display the image whose serial number differs by the predetermined number, when the image display unit is instructed, in the instructing step, to display the image whose serial number differs. 
     According to a fifth aspect of the invention, there is provided a recording medium storing an image display control program that is executed by a computer to cause an image display unit to display images in the order of the serial numbers of the images, in response to an instruction. The program describes the steps of: instructing the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed; generating data representing a multi-image consisting of images intervening between the image being displayed and the image whose serial number differs by the predetermined number, when the image display unit is instructed to display the image whose serial number differs; and causing the image display unit to display the intervening images represented by the data generated, and then to display the image whose serial number differs by the predetermined number. 
     According to a sixth aspect of the invention, there is provided a recording medium storing an image display control program that is executed by a computer to cause an image display unit to display images in the order of the serial numbers of the images, in response to an instruction. This program describes the steps of: instructing the image display unit to display an image whose serial number differs, by a predetermined number, from that of the image being displayed; and causing the image display unit to display images intervening between the image being displayed and the image whose serial number differs by the predetermined number, each for a different period, and then to display the image whose serial number differs by the predetermined number, when the image display unit is instructed to display the image whose serial number differs. 
     Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is a block diagram showing the configuration of a digital camera according to a first embodiment of this invention; 
         FIG. 2  is a perspective view of the camera according to the first embodiment, as viewed from the back; 
         FIG. 3  is a flowchart explaining how the digital camera according to the first embodiment is operated to display images; 
         FIGS. 4A to 4C  are diagrams explaining how a multi-image jump transfer is performed on the display screen in the first embodiment; 
         FIG. 5  is a flowchart explaining how the multi-image jump transfer is carried out in the first embodiment; 
         FIGS. 6A to 6D  are diagrams illustrating how multi-image jump transfer is achieved on the display screen in a second embodiment of this invention; 
         FIG. 7  is a flowchart explaining how the multi-image jump transfer is carried out in the second embodiment; 
         FIG. 8A to 8D  are diagrams illustrating how a multi-image jump transfer is achieved on the display screen in a third embodiment of the present invention; 
         FIG. 9  is a flowchart explaining how the multi-image jump transfer is performed in the third embodiment; 
         FIGS. 10A to 10E  are diagrams displaying how a multi-image jump transfer is performed on the display screen in a fourth embodiment of the present invention; 
         FIG. 11  is a flowchart explaining how the multi-image jump transfer is carried out in the fourth embodiment; 
         FIGS. 12A to 12E  are diagrams showing how a multi-image jump transfer is performed on the display screen in a fifth embodiment of the invention; 
         FIG. 13  is a flowchart illustrating how the multi-image jump transfer is carried out in the fifth embodiment; 
         FIGS. 14A to 14C  are diagrams showing the information displayed on a display screen in the sixth embodiment and explaining how a continuous reproduced-image jump transfer is performed; 
         FIG. 15  is a flowchart explaining how the continuous reproduced-image jump transfer is carried out in the sixth embodiment; 
         FIGS. 16A to 16C  are diagrams displaying how a continuous reproduced-image jump transfer is performed on the display screen in a seventh embodiment of this invention; 
         FIGS. 17A to 17C  are diagrams showing how a continuous reproduced-image jump transfer is performed on the display screen in an eighth embodiment of the present invention; 
         FIG. 18  is a flowchart explaining how the continuous reproduced-image jump transfer is carried out in the eighth embodiment; 
         FIGS. 19A to 19C  are diagrams showing how a continuous reproduced-image jump transfer is performed on the display screen in a ninth embodiment of the invention; 
         FIG. 20  is a flowchart explaining how the continuous reproduced-image jump transfer is carried out in the ninth embodiment; 
         FIGS. 21A to 21C  are diagrams showing how a continuous reproduced-image jump transfer is performed on the display screen in a tenth embodiment of the present invention; 
         FIG. 22  is a flowchart explaining how the continuous image-jump transfer is carried out in the tenth embodiment. 
     
    
    
     The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the invention, and together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the invention. 
     DETAILED DESCRIPTION OF THE INVENTION 
     Embodiments of the present invention will be described, with reference to the accompanying drawings. 
     First Embodiment 
       FIG. 1  is a block diagram showing the configuration of a digital camera according to the first embodiment of this invention. 
     As  FIG. 1  shows, the camera has a photographing unit  10 , an imaging unit  16 , a bus  20 , a CPU  22 , an operation unit  24 , a DRAM  26 , an image-processing unit  28 , a memory card  32 , an image display unit  34 , and a ROM  36 . 
     The photographing unit  10  has a photographing lens  12  and an imaging element  14 . Light beam from an object (not shown) passes through the photographing lens  12  and reaches the imaging element  14 . The imaging element  14  converts the light into an electric signal. The electric signal is supplied to the imaging unit  16 . The imaging unit  16  converts the signal to digital image data. 
     The bus  20  connects the imaging unit  16  to the CPU  22 , DRAM  26 , image-processing unit  28 , memory card  32  and image display unit  34 . 
     The CPU  22  controls some of the other components of the digital camera. The CPU  22  reads various control programs from the ROM  36  and executes them. Thus, the ROM  36  can function as an image-displaying control unit  22   a  and the like. The CPU  22  has a timer (not shown) and the like. The image-displaying control unit  22   a  executes the image-displaying control program, i.e., one of the control programs, so that various operations may be carried out as will be explained with reference to flowcharts. The CPU  22  is connected to the operation unit  24 . The operation unit  24  has switches (not shown) associated with selection buttons and OK button (later described), in addition to the power switch, the release switch and the zoom switch. 
     The DRAM  26  is a memory for temporarily storing image data to be processed and image data being processed. The image-processing unit  28  is an image-processing means for performing various processes on the image data to be stored in the memory card  32  or the image data read from the memory card  32 . 
     The memory card  32  is a recording medium for storing image data. It can be removed from the housing of the digital camera. 
     The image display unit  34  is, for example, an LCD panel. It can display the images represented by the data processed by the image-processing unit  28 . 
       FIG. 2  is a perspective view of the digital camera, as viewed from the back. 
     As  FIG. 2  shows, the digital camera has a housing  40  and a photographing lens  42 . The lens  42  is mounted on the front of the housing  40 . A release button  44 , a zoom button  46  and a display window  48  are provided on the upper surface of the housing  40 . When the user depresses the zoom button  46 , the camera performs zooming-up or zooming-down in accordance with the position that the zoom switch assumes. The display window  48  can display various items of data, including frame number or scenes to be photographed. 
     A finder window  50 , a selection pad  52 , a display (LCD) panel  54 , and a plurality of buttons  56  are provided on the back of the housing  40 . The selection pad  52  has four buttons  52   a  to  52   d.    
     The selection pad  52  is used to move a pointer cursor on the display window  48  or the LCD panel  54 . The buttons  52   a ,  52   b ,  52   c  and  52   d  are pushed, the pointer is moved upwards, to the left, to the right and downwards, respectively. Hence, they shall be referred to as “pointer-up button,” “pointer-left button,” “pointer-right button” and “pointer-down button,” respectively. The pointer-down button  52   d  works not only as pointer-down button, but also as jump key, stop key and display-continuation key. 
     The LCD panel  54  is the image display unit  34  shown in  FIG. 1 . It displays any images photographed. The buttons  56  are pushed to set the camera in various operating modes, including the photographing mode and the image-reproducing mode. 
     One of the buttons  56  is an OK button  56   a . When depressed, the OK button  56   a  set the camera in the mode that the user has just selected by pushing the OK button  56   a . When another button  56  is pushed, multi-image jump transfer is selected. When still another button  56  is pushed, continuous reproduced-image jump transfer is selected. When the remaining button  56  is pushed, the frame number of a desired image (or the number of a desired image) is designated. 
     It will be described how the digital camera described above operates to reproduce image data and display the image represented by the image data reproduced. How the camera operates to photograph an object and to perform any other function will not be described. 
     How the digital camera operates to display an image will be described, with reference to the flowchart of  FIG. 3 . 
     Assume that a data item may be read from the memory card  32  and input to the image-processing unit  28 . The unit  28  processes the data item, which is supplied to the image display unit  34  (i.e., LCD panel  54 ). The image display unit  34  displays the image represented by the data item in Step S 1 . In this condition, the image displayed on the LCD panel  54  can be switched to another, in accordance with which button of the selection pad  52  has been depressed. 
     In Step S 2 , it is determined whether the pointer-left button  52   b  has been depressed. If YES, the operation goes to Step S 3 . In Step S 3 , the LCD panel  54  displays the image of the immediately preceding frame. 
     If NO in Step S 2 , that is, if the pointer-left button  52   b  has not been depressed, the operation goes to Step S 4 . In Step S 4 , it is determined whether the pointer-right button  52   c  has been depressed. If YES in Step S 4 , the operation goes to Step S 5 . In Step S 5 , the LCD panel  54  displays the image of the immediately succeeding frame. 
     If NO in Step S 4 , or if the pointer-right button  52   c  has not been depressed, the operation goes to Step S 6 . In Step S 6 , it is determined whether the pointer-down button  52   d  has been depressed. If YES in Step S 6 , the camera is set into jump transfer mode. Thus, the LCD panel  54  displays an image several frames ahead, skipping the images of the intervening frames. 
     Then, the operation goes to Step S 7 . In Step S 7 , it is determined whether the image of any intervening frame, which is not displayed, is a multi-image that consists of a plurality of frames that are to be displayed on the LCD display  54  at the same time. If YES in Step S 7 , the operation goes to Step S 8 , in which a multi-image jump transfer is carried out. If NO in Step S 8 , the operation goes to Step S 9 , in which a continuous reproduced-image jump transfer is performed. 
     How the multi-image jump transfer mentioned above is performed will be explained, with reference to  FIGS. 4A to 4C  that show the information displayed by the LCD display  54  and  FIG. 5  that is a flowchart. 
     Assume that the LCD panel  54  displays the image of the first frame as is illustrated in  FIG. 4A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. 
     It should be noted that the numbers shown in  FIG. 4A to 4C  are the serial numbers assigned to frames of images. 
     First, in Step S 11 , the image-processing unit  28  reads image data from the memory card  23  and processes the data, generating data representing a multi-image. The multi-image consists of nine frames, i.e., frames  2  to  10  intervening between the frame  1  that is being displayed and the frame  11  which should be displayed next. To generate the multi-image data, the image-processing unit  28  performs a known method, which will not be described herein. 
     In Step S 12 , the multi-image data is supplied to the LCD panel  54 . The LCD panel displays the 9-frame multi-image represented by the multi-image data as shown in  FIG. 4B . The LCD panel  54  keeps displaying the multi-image until the time preset in the timer (not shown) provided in the CPU  22  elapses. The preset time is, for example, one second. In Step S 13 , it is determined whether the present time has elapsed. If NO in Step S 13 , the operation returns to Step S 12 . If YES in Step S 13 , the operation goes to Step S 14 . 
     In Step S 14 , the LCD panel  54  displays the frame  11  upon lapse of the preset time, as is illustrated in  FIG. 4C . 
     The LCD panel  54  displays a multi-image consisting of several frames. The user can perceive, at a glance, many frames represented by the data stored in the memory cared  23 . Namely, the user retrieves any desired frame from many, quickly and reliably. This would be impossible if the frames are sequentially displayed, each for a very short time, as by a display of the slide-showing type. 
     Second Embodiment 
     The second embodiment of the invention will be described, with reference to  FIGS. 6A to 6C  that show the information displayed on a display screen and  FIG. 7  that is a flowchart. 
     The camera according to this embodiment is identical to the camera according to the first embodiment, except the manner of performing the multi-image jump transfer. Hence, the components identical to those of the first embodiment will not be described but will be referred to, by using the same numerals. 
     During the multi-image jump transfer, the LCD panel  54  displays two or more multi-images one after another, not displaying only one multi-image as in the first embodiment. 
     Assume that the LCD panel  54  displays the image of the first frame as shown in  FIG. 6A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. In Step S 21 , the image-processing unit  28  reads image data from the memory card  32  and processes the data, generating data representing a multi-image. The multi-image consists of first nine of the frames intervening the first frame  1  and the last frame  20 . That is, the multi-image consists of the frames  2  to  10 . To generate the multi-image data, the image-processing unit  28  performs a known method, which will not be described herein. 
     In Step S 22 , the LCD panel  54  displays the first multi-image, or frames  2  to  10 , as shown in  FIG. 6B . In Step S 23 , it is determined whether the pointer-down button  52   d  has been depressed. If YES in Step S 23 , the LCD panel  54  stops displaying the first multi-image, and the operation jumps to Step S 27 . If NO in Step S 23 , the operation goes to Step S 24 . In Step S 24 , it is determined whether the time, e.g., one second, preset in the timer incorporated in the CPU  22  has elapsed. If NO in Step S 24 , the operation returns to Step S 22 . Hence, the LCD panel  54  keeps displaying the first multi-image until the reset time, for example 1 second, elapses. 
     If YES in Step S 24 , the operation goes to Step S 25 . In Step S 25 , it is determined whether there is any other multi-image. If YES in Step S 25 , the operation goes to Step S 26 . In Step S 26 , the number of images, n, is increased to n+1. Then, the operation returns to Step S 21 . In Step S 21 , the data representing the second multi-image, which consists of the frames  11  to  19 , is generated. In Step S 22 , the LCD panel  54  displays the second multi-image, i.e., frames  11  to  19 , as is illustrated in  FIG. 6C . Then, Steps S 21  to S 26  are repeated. 
     If NO in Step S 25 , the operation goes to Step S 27 . In Step S 27 , the LCD panel  54  displays, as shown in  FIG. 6D , the frame  20  to which image transfer jumps. 
     The second embodiment can display a plurality of multi-images, one after another. The user can therefore recognize the intervening frames, too, no matter how many. 
     Third Embodiment 
     The third embodiment of the invention will be described, with reference to  FIGS. 8A to 8D  that show the information displayed on a display screen and  FIG. 9  that is a flowchart. 
     The camera according to the third embodiment performs a multi-image jump transfer, too, but in a different way. More specifically, the LCD panel  54  continuously displays one multi-image, not multi-images one after another as in the second embodiment. 
     Assume that the LCD panel  54  displays the image of the first frame as shown in  FIG. 8A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. In Step S 31 , the image-processing unit  28  reads image data from the memory card  32  and processes the data, generating data representing a multi-image. The multi-image consists of the frames  2  to  10 , which are the first nine of 18 frames intervening between the frame  1  and the frame  20 . To generate this multi-image data, the unit  28  performs a known method, which will not be described herein. The image-processing unit  28  does not generate data representing a multi-image consisting of the frames  11  to  19 , i.e. other frames intervening between the frame  1  and the frame  20 . 
     In Step S 32 , the LCD panel  54  displays the multi-image, or the frames  2  to  10  as shown in  FIG. 8B . In Step S 33 , it is determined whether the OK button  56   a  has been depressed. If NO in Step S 33 , the operation goes to Step S 34 . In Step S 34 , it is determined whether the time, e.g., one second, preset in the timer incorporated in the CPU  22  has elapsed. If NO in Step S 34 , the operation returns to Step S 32 . If YES in Step S 34 , the operation goes to Step S 35 . 
     In Step S 35 , it is determined whether there is any other multi-image should be displayed. If YES, the operation goes to Step S 36 . In Step S 36 , the number of images, n, is increased to n+1. Then, the operation returns to Step S 31 . Steps S 31  to S 35  are then repeated. 
     If NO in Step S 35 , the operation goes to Step S 37 . In Step S 37 , the LCD panel  54  displays the frame  20  (not shown) to which the image transfer jumps. 
     The second embodiment can display a plurality of multi-images, one after another. The user can therefore recognize the intervening frames, too, no matter how many. 
     If YES in Step S 33 , or if the OK button  56   a  has been depressed, the operation goes to Step S 38 . In Step S 38 , the multi-image jump transfer is stopped. As a result, the LCD panel  54  keeps displaying the multi-image (i.e., frames  2  to  10 ), which was being displayed when the OK button  56   a  was depressed. Since the multi-image jump transfer is no longer performed, the LCD panel  54  displays neither a multi-image ( FIG. 8C ) nor the frame  20  (not shown) that should be displayed next. 
     Once the multi-image jump transfer is stopped, the multi-image (i.e., frames  2  to  10 ) displayed on the LCD panel  54  has a rectangular frame that encircles the frame that the user has selected. The frame may encircle, for example, the center frame  6  as is illustrated in  FIG. 8D . 
     Alternatively, the LCD panel  54  may display only one frame selected, when the multi-image jump transfer is stopped in Step S 38 . 
     Thus, the third embodiment can stop the multi-image jump transfer when the user pushes the OK button  56   a  upon finding a desired frame in the multi-image displayed on the LCD panel  54 . 
     Fourth Embodiment 
     The fourth embodiment of the invention will be described, with reference to  FIGS. 10A to 10E  that show the information displayed on a display screen and  FIG. 11  that is a flowchart. 
     The camera according to this embodiment performs a multi-image jump transfer, too, but in a different way. To be more specific, the LCD panel  54  continuously displays multi-images, each consisting of a different number of frames, not consisting of nine frames as in the first to third embodiments. 
     Assume that the LCD panel  54  displays the image of the first frame, i.e., frame  1 , as shown in  FIG. 10A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. In Step S 41 , the image-processing unit  28  generates data representing a first multi-image that should be displayed next to the frame  1 . The first multi-image consists of four frames (or, m×m frames). To generate the first multi-image data, the unit  28  performs a known method, which will not be described herein. 
     In Step S 42 , the LCD panel  54  displays the multi-image, or the frames  2 ,  3 ,  5  and  6 , as shown in  FIG. 10B . In Step S 43 , it is determined whether the time, e.g., one second, preset in the timer (not shown) incorporated in the CPU  22  has elapsed. If NO in Step S 43 , the operation returns to Step S 42 . If YES in Step S 43 , the operation goes to Step S 44 . 
     In Step S 44 , the image-processing unit  28  generates data representing the second multi-image that consists of 3×3 (m+1×m+1, m=2) frames. Namely, the second multi-image consists of nine frames. It is larger and more extending horizontally and vertically by one frame, than the first multi-image that is being displayed. 
     In Step S 45 , the LCD panel  54  displays the second multi-image consisting of the frames  2  to  10  as is illustrated in  FIG. 10C . In Step S 46 , it is determined whether the time, e.g., one second, preset in the timer has elapsed. If NO in Step S 46 , the operation returns to Step S 45 . If YES in Step S 46 , the operation goes to Step S 47 . 
     In Step S 47 , it is determined whether another multi-image exists, which consists of as many frames as the second multi-image. If YES in Step S 47 , the operation goes to Step S 48 . In Step S 48 , the number of images, n, is increased to n+1. Then, the operation returns to Step S 44 . Steps S 44  to S 47  are then repeated. 
     If NO in Step S 47 , or if another multi-image does not exists, which consists of as many frames as the second multi-image, the operation goes to Step S 49 . In Step S 49 , the image-processing unit  28  generates data representing a third multi-image that consists of 2×2 (m×m, m=2) frames. Namely, the third multi-image consists of four frames. It is smaller and less extending horizontally and vertically by one frame, than the second multi-image that is being displayed. 
     In Step S 50 , the LCD panel  54  displays the four-frame multi-image as depicted in  FIG. 10D . The LCD panel  54  keeps displaying this multi-image until the time, e.g., one second, preset in the timer elapses. 
     In Step S 51 , it is determined whether the time, e.g., one second, preset in the timer has elapsed or not. If YES in Step S 51 , the operation goes to Step S 52 . In Step S 52 , the LCD panel  54  displays, as shown in  FIG. 10E , the frame  11  to which the image transfer jumps. 
     In the fourth embodiment, the LCD panel  54  sequentially displays a 1-frame image, a 4-frame image, a 9-frame image, a 4-fame image and a 1-frame image, in the order they are mentioned. In other words, the first and last image the LCD panel  54  displays are 1-frame images, and the intervening images the LCD panel  54  differs in the number of constituent frames. The image displayed can be switched more quickly from a 1-frame image to a 4-frame image, than to a 9-frame image. 
     In the fourth embodiment, the number of frames the LCD  54  displays at a time is changed. The size of any frame displayed changes in inverse proportion to the number of frames simultaneously displayed. This makes it easier for the user to recognize the frames than the case where each frame is displayed in the same size, no matter whether it is displayed alone or together with any other frames. 
     In the fourth embodiment, the multi-images consist of four frames or nine frames each. Nonetheless, they may consist of any other number of frames. 
     The multi-image shown in  FIG. 10B  consists of first adjacent four (i.e., frames  2 ,  3 ,  5  and  6 ) of the frames  2  to  10  constituting the nine-frame multi-image depicted in  FIG. 10C . The multi-image shown in  FIG. 10D  consists of the other four adjacent frames (i.e., frames  6 ,  7 ,  9  and  10 ). Instead, the first multi-image may consists of the first four consecutive frames  2  to  5 , and the second multi-image may consists of the next four consecutive frames  6  to  9 . 
     Fifth Embodiment 
     The fifth embodiment of this invention will be described, with reference to  FIGS. 12A to 12E  that show the information displayed on a display screen and  FIG. 13  that is a flowchart. 
     The camera according to the fifth embodiment performs a multi-image jump transfer, too. Nevertheless, some multi-images may not be displayed once the multi-image jump transfer has been initiated. 
     Assume that the LCD panel  54  displays the image of the first frame, i.e., frame  1 , as shown in  FIG. 12A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. In Steps S 61 , the image-processing unit  28  generates data representing a first multi-image that should be displayed next to the frame  1 , as in Step S 41  shown in the flowchart of  FIG. 11 . Then, in Step S 62 , the LCD panel  54  displays the first multi-image, which consists of four frames (or, m×m frames), as in Step S 42  shown in the flowchart of  FIG. 11 . 
     In Step S 63 , it is determined whether the whether the pointer-down button  52   d  has been depressed while the LCD panel  54  is displaying the 4-frame multi-image. If YES in Step S 63 , the operation jumps to Step S 75 . If NO in Step S 63 , the operation goes to Step S 64 . 
     In Step S 64 , it is determined whether the time, e.g., one second, preset in the timer (not shown) provided in the CPU  22  has elapsed or not. If NO in Step S 64 , the operation returns to Step S 62 . If YES in Step S 64 , the operation goes to Step S 65 . 
     In Step S 65 , the image-processing unit  28  generates data representing a second multi-image that consists of 3×3 (m+1×m+1, m=2) frames. Namely, the second multi-image consists of nine frames. It is larger and more extending horizontally and vertically by one frame, than the first multi-image that is being displayed. 
     Next, in Step S 66 , the LCD panel  54  displays the second multi-image consisting of nine frames. In Step S 67 , it is determined whether the pointer-down button  52   d  has been depressed while the LCD panel  54  is displaying the 9-frame multi-image. If YES in Step S 67 , the operation jumps to Step S 75 . If NO in Step S 67 , the operation goes to Step S 68 . 
     In Step S 68 , it is determined whether the time, e.g., one second, preset in the timer has elapsed. If NO in Step S 68 , the operation returns to Step S 66 . If YES in Step S 68 , the operation goes to Step S 69 . 
     Steps S 69  to S 72  are identical to Steps  47  to  50  shown in the flowchart of  FIG. 11 , and will not be explained in detail. 
     In Step S 73 , it is determined whether the pointer-down button  52   d  has been depressed while the LCD panel  54  is displaying the 4-frame multi-image. If YES in Step S 73 , the operation jumps to Step S 75 . If NO in Step S 73 , the operation goes to Step S 74 . 
     In Step S 74 , it is determined whether the time, e.g., one second, preset in the timer has elapsed. If NO in Step S 74 , the operation returns to Step S 72 . If YES in Step S 74 , the operation goes to Step S 75 . In Step S 75 , the LCD panel  54  displays, as shown in  FIG. 12E , the frame  11  to which the image transfer jumps. 
     In Step S 63 , S 67  or S 73 , it may be determined that the pointer-down button  52   d  has been depressed. If this is the case, the operation goes to Step S 75 . If it is determined in, for example, Step S 63  that the button  52   d  has been depressed, the LCD panel  54  stops displaying the 4-frame multi image. Thereafter, the LCD panel  54  displays neither the 9-frame multi image of  FIG. 12C  nor the 4-frame multi-image of  FIG. 12D , and the operation goes to Step S 75 . In Step S 75 , the LCD panel  54  displays, as shown in  FIG. 12E , the frame  11  that should be displayed next. 
     Thus, the image transfer can jump from the frame  1  ( FIG. 12A ) to the frame  11  ( FIG. 12E ). That is, the LCD does not display the intervening frames  2  to  10  at all. 
     Sixth Embodiment 
     The sixth embodiment of this invention will be described. 
       FIGS. 14A to 14C  are diagrams showing the information displayed on a display screen in the sixth embodiment and explaining how a continuous reproduced-image jump transfer is performed.  FIG. 15  is a flowchart explaining how a continuous reproduced-image jump transfer is carried out in the sixth embodiment. 
     A digital camera according to the sixth embodiment is identical to the first embodiment in structure and operation, except that performs the continuous reproduced-image transfer. Hence, the components identical to those of the first embodiment will not be described but will be referred to, by using the same numerals. 
     How this camera operates will be described, with reference to the flowchart of  FIG. 3 . If NO in Step S 7 , or if it is determined that the image of any intervening frame is a multi-image that consists of two or more frames to be displayed on the LCD display  54  at the same time, the digital camera starts the routine of the continuous reproduced-image jump transfer. 
     If the user pushes the pointer-down button  52   d  while the LCD display  54  is displaying the frame  1  as shown in  FIG. 14A , the camera starts the main routine. In Step S 81 , the number of frame  1  being displayed, i.e., “1”, is increased to “2.” The first frame to be displayed in the continuous reproduced-image transfer is set. In Step S 82 , the image-processing unit  28  generates data representing the frame  2 . 
     In Step S 83 , the periods for which the images represented by the data should be displayed, respectively, are set to the timer (not shown) incorporated in the CPU  22 . Each of the first few images is displayed longer than the following one, and each of the remaining images is displayed shorter than the following one. For example, the periods for which the images are displayed, respectively, are set as is shown in Table 1 set forth below. The contents of Table 1 are stored in the CPU  22  or a memory (not shown) provided outside the CPU  22 . 
     
       
         
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 Different Periods of Displaying Frames 
               
             
          
           
               
                 Frame 
                 Actual Frame 
                 Display Period 
               
               
                 No. 
                 No. 
                 (sec) 
               
               
                   
               
               
                 n + 1 
                 2 
                 0.3 
               
               
                 +2 
                 3 
                 0.3 
               
               
                 +3 
                 4 
                 0.2 
               
               
                 +4 
                 5 
                 0.2 
               
               
                 +5 
                 6 
                 0.1 
               
               
                 +6 
                 7 
                 0.1 
               
               
                 +7 
                 8 
                 0.2 
               
               
                 +8 
                 9 
                 0.3 
               
               
                 +9 
                 10  
                 0.3 
               
               
                   
               
             
          
         
       
     
     More specifically, the image transfer jumps from the frame  1  to the frame  11 . Of the frames intervening these frames  1  and  11 , the frames  2  and  3  are displayed for 0.3 seconds, the frames  4  and  5  for 0.2 seconds, the frames  6  an  7  for 0.1 seconds, the frame  8  for 0.2 seconds, and the frames  9  and  10  for 0.3 seconds. 
     In Step S 84 , the LCD panel  54  displays the frame represented by the data generated in Step S 82 . In Step S 85 , it is determined whether the display period set in Step S 83  for this frame has elapsed. The display period corresponding to the serial number of the frame is determined. 
     Next, in Step S 86 , it is determined whether the continuous image reproduction comes to the last frame, i.e., frame  10 . If NO in Step S 86 , the operation goes to Step S 87 . In Step S 87 , the frame number n, is increased to n+1. Thereafter, the operation returns to Step S 82 . Steps S 82  to S 86  are repeated. Thus, the frames intervening the frame  1  and the frame  11  are displayed one after another, each for a different period, as is illustrated in  FIG. 14B . 
     If YES in Step S 86 , or if the continuous image reproduction comes to the last frame, i.e., frame  10 , the operation goes to Step S 88 . In Step S 88 , the LCD  54  displays the last frame  11 , to which the image transfer has jumped from the frame  1 , as is illustrated in  FIG. 14C . 
     Thus, in the sixth embodiment, the frames intervening the first and last frames are displayed, not at regular intervals, but each for a different period. This makes the user feel that the image transfer proceeds more vividly and renders it easier for the user to retrieve any desired frame. Further, the middle part of the series of frames can be quickly displayed, because this part consists of frames (e.g., frames  6  and  7 ) that are displayed, each for a shorter period than the other frames. 
     Seventh Embodiment 
     The seventh embodiment of this invention will be described. 
     In the sixth embodiment, the frames intervening the frame  1  and the frame  11  are sequentially displayed, each for a different period. In the seventh embodiment, each intervening frame is displayed for a period that is proportional to the period between the photographing of the frame and the photographing of the immediately preceding frame. 
     In the seventh embodiment, the continuous reproduced-image jump transfer is performed in the same way as in the sixth embodiment and as shown in the flowchart of  FIG. 15 , except for one respect only. That is, the periods for which the intervening frames should be displayed and which are set to the timer are different from those shown in Table 1. 
     To be more specific, the periods set to the timer are as shown in the following Table 2 and as will be explained below, with reference to  FIGS. 16A to 16C . 
     
       
         
               
             
               
               
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 Different Periods of Displaying Frames 
               
             
          
           
               
                   
                 Frame 
                 Actual 
                 Photo. 
                 Display Period 
               
               
                   
                 No. 
                 Frame No. 
                 Interval 
                 (sec) 
               
               
                   
                   
               
               
                   
                 n + 1 
                 2 
                 — 
                   
               
               
                   
                 +2 
                 3 
                 1 hr or more 
                 0.6 
               
               
                   
                 +3 
                 4 
                 less than 1 hr 
                 0.3 
               
               
                   
                 +4 
                 5 
                 less than 1 hr 
                 0.3 
               
               
                   
                 +5 
                 6 
                 1 hr or more 
                 0.6 
               
               
                   
                 +6 
                 7 
                 less than 1 hr 
                 0.3 
               
               
                   
                 +7 
                 8 
                 1 hr or more 
                 0.6 
               
               
                   
                 +8 
                 9 
                 less than 1 hr 
                 0.3 
               
               
                   
                 +9 
                 10  
                 less than 1 hr 
                 0.3 
               
               
                   
                   
               
             
          
         
       
     
     The data representing each frame contains data item that shows when the frame has been photographed. The CPU  22  reads two data items from the memory card  32 , one item indicating the time of photographing one frame and the other item indicating the time of photographing the immediately following frame. The CPU  22  then compares these data items, calculating the photographing interval. 
     After displaying the first as shown in  FIG. 16A , the LCD  54  displays the second frame, which is the first intervening frame. Then, the LCD  54  displays the second frame for 0.6 seconds because the second and third frames have been photographed with time gap Δt1 of one hour or more as shown in Table 2. Next, the LCD  54  displays the third frame and the fourth frame sequentially, each for 0.3 seconds, because the third and fourth frames have been photographed with time gap Δt2 of less than hour and the fourth and fifth frames have been photographed with time gap Δt3 of less than hour. Similarly, the LCD  54  displays the sixth to tenth frames, each for a different period determined by the time gap between the photographing of the frame and the photographing of the immediately preceding frame. Thus, as  FIG. 16B  depicts, the frames  2  to  10  intervening between the frames  1  and  11  are displayed for different periods. 
     Finally, the LCD panel  54  displays the frame  11  to which the image transfer has jumped from the frame  1 , as is illustrated in  FIG. 16C . 
     As described above, the frames intervening between the first and last frames are displayed not for the same period in the seventh embodiment. Rather, they are displayed for different periods, each period determined by the time gap between the photographing of the frame and the photographing of the immediately preceding frame. This enables the user to retrieve any desired frame within a short time. 
     Eighth Embodiment 
     The eighth embodiment of the invention will be described, with reference to  FIG. 17A to 17C  and  FIG. 18 .  FIGS. 17A to 17C  are diagrams showing the information displayed on a display screen in the eighth embodiment.  FIG. 18  is a flowchart. 
     In the eighth embodiment, the continuous reproduced-image jump transfer is performed, in which some of the frames intervening the first and last frames are not displayed at all. 
     First, the LCD panel  54  displays the image of the first frame, i.e., frame  1 , as shown in  FIG. 17A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. In Step S 91 , the number of frame  1  being displayed, i.e., “1”, is increased to “2.” The first frame to be displayed in the continuous reproduced-image transfer is set. In Step S 92 , the image-processing unit  28  generates data representing the frame  2 . In Step S 92 , the LCD panel  54  displays the frame  2  represented by the data. 
     In Step S 94 , it is determined whether the pointer-down button  52   d  has been depressed. If YES in Step S 94 , the operation jumps to Step S 99 . If NO in Step S 94 , the operation goes to Step S 95 . 
     In Step S 95 , it is determined whether the time, e.g., one second, preset in the timer provided in the CPU  22  has elapsed. If NO in Step S 95 , the operation returns to Step S 93 . If YES in Step S 95 , the operation goes to Step S 96 . 
     In Step S 96 , it is determined whether the last intervening frame, i.e., the frame  10 , has been subjected to the continuous reproduction. If NO in Step S 96 , the operation goes to Step S 97 . In Step S 97 , the number of frame, n, is increased to n+1. Thereafter, the operation returns to Step S 92 . Steps S 92  to S 96  are then repeated. 
     If YES in Step S 96 , or if the last intervening frame (i.e., frame  10 ) has been subjected to the continuous reproduction, the operation goes to Step  98 . In Step S 98 , the LCD panel  54  displays the frame  11  to which the image transfer has jumped from the frame  1 , as is depicted in  FIG. 17C . 
     If YES in Step S 94 , or if the pointer-down button  52   d  has been depressed, the operation jumps to Step S 99 . In Step S 99 , the frames  6  to  10  are skipped. Thus, as shown in  FIG. 17B , the frames  6  to  10  are not displayed at all. The operation then goes to Step S 98 , in which the LCD panel displays the frame  11  to which the image transfer has jumped from the frame  1 . 
     In the eighth embodiment, the last several of the frames intervening the first frame  1  and the last several frame  11  are not displayed at all. Hence, the image transfer can jump to the last frame more quickly. This enables the user to retrieve any desired frame faster. 
     Ninth Embodiment 
     The ninth embodiment of this invention will be described, with reference to  FIG. 19A to 19C  and  FIG. 20 .  FIGS. 19A to 19C  are diagrams showing the information displayed on a display screen in the ninth embodiment.  FIG. 20  is a flowchart. 
     The camera according to the ninth embodiment performs a continuous reproduced-image jump transfer. It can display the frames intervening between the first frame displayed and the last frame to be displayed, continuously one after another. 
     Assume that the LCD panel  54  displays the image of the first frame, i.e., frame  1 , as shown in  FIG. 19A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. Steps S 101  to S 103  are sequentially performed. These steps, which are identical to Steps S 91  to S 93  shown in  FIG. 18 , will not be described here. 
     In Step S 104 , it is determined whether the OK button  56   a  has been depressed. If NO in Step S 104 , the operation goes to Step S 105 . In Step S 105 , it is determined whether the time, e.g., one second, preset in the timer incorporated in the CPU  22  has elapsed. If NO in Step S 105 , the operation returns to Step S 103 . If YES in Step S 105 , the operation goes to Step S 106 . 
     In Step S 106 , it is determined whether the last intervening frame, i.e., the frame  10 , has been subjected to the continuous reproduction. If NO in Step S 106 , the operation goes to Step S 107 . In Step S 107 , the number of frame, n, is increased to n+1. Thereafter, the operation returns to Step S 102 . Steps S 102  to S 106  are then repeated. 
     If YES in Step S 106 , or if the last intervening frame (i.e., frame  10 ) has been subjected to the continuous reproduction, the operation goes to Step S 108 . In Step S 108 , the LCD panel  54  displays the frame  11  to which to which the image transfer has jumped from the frame  1 . 
     If YES in Step S 104 , or if the OK button  56   a  is depressed, the operation goes to Step S 109 . In Step S 109 , the continuous reproduced-image jump transfer is stopped. In this case, the LCD panel  54  displays the last frame subjected to the transfer, e.g., the frame  6 , as is illustrated in  FIG. 19C . Now that the continuous transfer of the intervening frame has been stopped, the frames  7  to  10  are not displayed. 
     Thus, the user can stop the continuous transfer of the intervening frames when he or she finds a frame to retrieve or when he or she wants to stop searching for desired frames. 
     Tenth Embodiments 
     The tenth embodiment of this invention will be described, with reference to  FIG. 21A to 21C  and  FIG. 22 .  FIGS. 21A to 21C  are diagrams showing the information displayed on a display screen in the tenth embodiment.  FIG. 22  is a flowchart. 
     The camera according to the tenth embodiment performs a continuous reproduced-image jump transfer, too. It can display only specified ones of the frames intervening between the first and last frames  1  and  11 . 
     First, the LCD panel  54  displays the first frame, i.e., frame  1 , as illustrated in  FIG. 21A . When the user pushes the pointer-down button  52   d , the digital camera starts the main routine. In Step S 111 , the number of frame  1  being displayed, i.e., “1”, is increased by a specific value. The value of increment may be any number desired. In this case, it is “2.” Hence, the number of frame is increased from “1” to “3.” 
     In Step S 112 , the image-processing unit  28  generates data representing the frame  3 . In Step S 113 , the LCD panel  54  displays the frame  3  represented by the data. 
     In Step S 114 , it is determined whether the time, e.g., one second, preset in the timer incorporated in the CPU  22  has elapsed. If NO in Step S 114 , the operation returns to Step S 113 . If YES in Step S 114 , the operation goes to Step S 115 . 
     In Step S 115 , it is determined whether the last intervening frame, i.e., the frame  9  in this case, has been subjected to the continuous reproduction. If NO in Step S 115 , the operation goes to Step S 116 . In Step S 116 , the number of frame, n, is increased to n+2. Thereafter, the operation returns to Step S 112 . Steps S 112  to S 115  are then repeated. 
     If YES in Step S 115 , or if the last intervening frame (i.e., frame  9 ) has been subjected to the continuous reproduction, the operation goes to Step S 117 . In Step S 117 , the LCD panel  54  displays the frame  11  to which to which the image transfer has jumped from the frame  1 , as is illustrated in  FIG. 21C . 
     Thus, the LCD panel  54  can display one intervening frame out of very n frames, for example, every other intervening frame as is shown in  FIG. 21B . 
     Hence, the time required to display the frame intervening between the first frame  1  and the last frame  11  can be shortened in the tenth embodiment. 
     In the embodiments described above, the image jump transfer proceeds in the ascending order of frames. Instead, it may proceed in the descending order of frames in the present invention. 
     Further, the image jump transfer is carried out on the basis of the serial numbers of the frames. Instead, it may be performed in accordance with the numbers assigned to the frames to accomplish an efficient management of the frames. 
     The embodiments described above are digital cameras. This invention is not limited to digital cameras, nonetheless. The present invention can be applied to apparatuses of any other types that reproduce image data from recording media and display the images represented by the data, such as the camera unit for use in mobile telephones, the display unit for use in PDAs, and the like. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.