Abstract:
A digital image and speech recording and reproducing apparatus is arranged to quickly and simply retrieve, classify, and erase a great deal of data for improving the operativity in small-sized equipment. The apparatus includes a recording and reproducing unit for a moving image signal, a recording and reproducing unit for a still image signal, a recording and reproducing unit for a digital speech signal operated in synchronous to the image, a display for displaying the image for said moving image signal or said still image signal, a recording condition recording unit for recording recording conditions containing data information about recorded data for distinguishing said moving image from said still image and recording time information for recording an image or a speech. The recording conditions consisting of at least the data information and the recording time information about the recorded data are graphically and literarily displayed on the display, so that the recorded data item may be selected on the display screen.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to operativity of a portable digital camcorder.  
           [0002]    The prior art relevant to the portable digital camcorder has been published as an electronic photograph system, that is, the so-called electronic still camera that is arranged to record a still image signal as a video signal in a memory composed of a semiconductor (termed as a semiconductor memory or simply a memory) as disclosed in JP-A-2-292974. With recent prevail of personal computers, recording mediums such as semiconductor memories and harddisks are progressively made lower in cost, smaller in size, and greater in capacity. At a time, the advance of signal compressing technology such as JPEG or MPEG allows even the small-sized equipment to record greater number of still images and moving ones. Taking a harddisk drive as an example, the resulting harddisk drive is kept as small as a card and has as great a capacity as about 300 Mbytes.  
           [0003]    This type of harddisk drive enables to record about 3000 still images through the use of the JPEG compression and about 20-minutes moving picture through the use of the MPEG compression. It is thus necessary to improve the operativity of the portable equipment for retrieving, grouping, and deleting a great deal of recording data. The technique disclosed in JP-A-2-292974, however, does not provide means for retrieving a great deal of recording data quickly and easily. In actual, therefore, the technique does not have any means except the method of retrieving the great deal of recorded data as checking all images reproduced on screen from the recorded data.  
           [0004]    In case that 3000 JPEG still images are recorded on a feasible media such as the aforementioned harddisk drive and then are retrieved as expanding those images on the screen one by one, about one second for expanding one JPEG still image is required. It means that the expansion of 3000 images needs about one hour. This method lacks in practicability. In order to retrieve a great deal of data, therefore, it is necessary to enhance the operating speed of the system.  
         SUMMARY OF THE INVENTION  
         [0005]    It is an object of the present invention to provide an apparatus which is arranged to overcome the foregoing shortcoming and enhance the operativity even if the apparatus is small-sized.  
           [0006]    In carrying out the object, for improving the operativity of a small-sized apparatus, the present invention is achieved by an apparatus which comprises recording means for recording both imaging time information and imaging mode information for distinguishing moving images from still images at a time when taking the still image or moving image, display means for displaying as a list the informations as well as expanded images on a liquid crystal display screen built in the main body of the apparatus itself, and keying means for retrieving, classifying, and erasing the recorded data.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0007]    [0007]FIG. 1 is a diagram showing a state transition of a program used in an apparatus according to the present invention;  
         [0008]    [0008]FIG. 2 is a view showing an outer appearance of a portable digital camcorder in which the program of FIG. 1 is executed;  
         [0009]    [0009]FIG. 3 is an expanded view showing an operating switch portion provided in the portable digital camcorder in which the program of FIG. 1 is executed;  
         [0010]    [0010]FIG. 4 is a circuit diagram showing an arrangement of a portable digital camcorder in which the program of FIG. 1 is executed;  
         [0011]    [0011]FIG. 5 is a view showing a display screen provided in the portable digital camcorder in which the program of FIG. 1 is executed;  
         [0012]    [0012]FIG. 6 is a view showing a display screen on which the recorded data is classified;  
         [0013]    [0013]FIG. 7 is a view showing a display screen on which the recorded data is selected;  
         [0014]    [0014]FIG. 8 is a view showing a display screen with expanded images in which the recorded data is selected;  
         [0015]    [0015]FIG. 9 is a view showing a display screen on which the function details of the recorded data are selected;  
         [0016]    [0016]FIG. 10 is a flowchart showing a method for selecting the function details;  
         [0017]    [0017]FIG. 11 is a view showing a display screen on which the classifications of the recorded data are changed;  
         [0018]    [0018]FIG. 12 is a view showing a display screen on which the displaying sequence of the recorded data is changed;  
         [0019]    [0019]FIG. 13 is a view showing a display screen on which each date of the recorded data is changed;  
         [0020]    [0020]FIG. 14 is a view showing a display screen on which each erasing attribute of the recorded data is changed;  
         [0021]    [0021]FIG. 15 is a view showing a display screen on which a remaining state of the recording medium is displayed;  
         [0022]    [0022]FIG. 16 is a flowchart showing a method for reading recorded data from a harddisk driver and reproducing it;  
         [0023]    [0023]FIG. 17 is a view showing an imaged screen appearing if a still image recording mode is selected when recording an image;  
         [0024]    [0024]FIG. 18 is a view showing an imaged screen appearing if a moving image recording mode is selected when recording an image; and  
         [0025]    [0025]FIG. 19 is a view showing marks for modes;  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0026]    Later, the description will be oriented to the embodiments of the present invention with reference to FIGS.  1  to  19 .  
         [0027]    [0027]FIG. 1 shows a flow of a software program according to an embodiment of the present invention.  
         [0028]    The software program shown in FIG. 1 flows through the process of selecting a classification containing data to be played back or handled ( 101 ) and reaches the process of playing back the data ( 103 ) or flows to a function selecting items ( 105 ) in which a temporary discard ( 106 ), a complete abandon ( 107 ), a state display ( 112 ) of a storage unit, setting of protection from erasion ( 111 ), change of a display list ( 109 ), or change of a record date and hour ( 110 ) is selected. Moreover, when selecting a classification ( 101 ), the flow goes to the function selecting items ( 105 ) in which a temporary discard ( 106 ), a complete abandon ( 107 ), a state display of a storage unit ( 112 ), or automatic playback is selected. In the playback ( 103 ), a move to next data ( 115 ), a move to previous data ( 116 ), a fast playback ( 117 ), a rewind playback ( 118 ), or a temporary stop ( 121 ) is selected. In the temporary stop ( 121 ), a forward frame advance ( 119 ) or reverse frame advance ( 120 ) is selected.  
         [0029]    [0029]FIG. 2 shows an example of an outer appearance of a portable digital camcorder  200  in which the software program shown in FIG. 1 is executed. This camcorder  200  provides a capability of recording and reproducing an NTSC or PAL TV system signal.  
         [0030]    [0030]FIG. 3 is an expanded view showing an operating switch portion of the portable digital camcorder shown in FIG. 2. In the portable digital camcorder  200  shown in FIG. 2, with the operating switches, a digital moving signal obtained from the camera system is compressed to one MPEG (Moving Picture Expert Group) format and then is recorded on a harddisk storage medium sized to a memory card. In the playback, with the operating switches, the MPEG 1  format signal recorded in a memory card is expanded and then displayed on a display unit  201  built in the camcorder itself. The display unit may be connected to the outside of the camcorder  201 . The portable digital camcorder  200  shown in FIG. 2 may recorded the MPEG moving image data as well as the JPEG data for the still images and the MPEG speech format for the speech data.  
         [0031]    [0031]FIG. 4 schematically shows a circuit arrangement of the portable digital comcorder  200 . At first, the description will be oriented to the procedure of recording the moving image through the portable digital camcorder  200 . When a user presses a recording switch  301 , an image of an object obtained through a lens  401  is converted into the corresponding electric signal through the effect of a CCD sensor  402 . The signal read out of a sensor is electrically processed through a CDS (Correlated Double Sampling) circuit for suppressing the low-frequency noises of the signal and a circuit  403  integrated with a AGC circuit for controlling an automatic gain of the signal for stabilizing the signal level. Then, the processed signal is converted into a digital signal through an ADC  404  and then is applied to a camera signal processing circuit  405 .  
         [0032]    A camera signal processing circuit (camera DSP)  405  is configured of a function of converting a digital pixel signal from the sensor into a luminance signal Y and color difference signals U and V, a function of adding a synchronous signal, a function of controlling relation between an iris and a shutter speed, a function of adjusting a white balance, and a function of digitally zooming in or out the signal. Though not illustrated in detail in FIG. 4, the camera DSP  405  is operated to feed a horizontal and a vertical driving signal pulses to the CCD sensor  402  and read the signal from the CCD sensor  402  as adjusting the timing between the synchronous signal and the pulses. Moreover, a camera control microcomputer  406  is operated to feed operating parameters for the DSP  405  to the camera DSP  405  in order to control the overall camera system.  
         [0033]    On the other hand, the digital luminance signal Y and the digital color difference signals U and V obtained by the camera DSP  405  are sent to an MPEG 1  encoder  409  through a digital bus line. The MPEG 1  is a standard compression format for the digital signal for a moving image. The encoder  409  operates to compress the data according to the MPEG 1  format and then convert it into the digital data. A numeral  410  denotes a working memory used in encoding the data according to the MPEG 1  format. The data converted into the MPEG 1  format is sent to a microcomputer  411  for controlling a transmission rate of the digital output data. The MPEG 1  encoder  409 , the working memory  410  and the microcomputer  411  compose the overall system for compressing the moving image.  
         [0034]    The microcomputer  411  for controlling the transmission rate stores a constant amount of MPEG 1 -formatted data in a buffer memory  412 . The formatted data is passed through an interface circuit  413  and a card connector  414  and reaches a harddisk drive  415 . The card connector  414  is configured on the PCMCIA standards and thus contains 68 pins. The harddisk drive  415  is sized to a memory card and subject to the PC card standards defined by the PCMCIA (Personal Computer Memory Card International Association).  
         [0035]    The foregoing description has concerned with the method for recording the moving image. In case the still image recording mode is selected by the user, the MPEG encoder  409  is switched to a JPEG compressing circuit. Then, a still image data is generated at the encoder  409  and then transferred to the microcomputer  411  for doing the same operation as described above. The MPEG compression data process and the JPEG compression data process have the same common points, so that the use of both the data formats may effectively save the circuit scale. This is a well-known method for saving the circuitry.  
         [0036]    Further, the speech signal is converted into an analog electric signal through a microphone  418 . The analog electric signal is sent to a speech ADC  419  for converting the analog electric signal into the corresponding digital data. The digital speech data is applied into the data bus through the effect of the MPEG encoder  409 . Then, the microcomputer  411  performs the MPEG-format-based compression through the program run therein so that the digital speech data is added to the moving image data or the still image data in precise time sequences.  
         [0037]    According to this embodiment, the portable digital camcorder  200  is arranged to record the MPEG 1 -formatted data, the JPEG-formatted data, and the MPEG 1 -formatted speed data.  
         [0038]    In recording the data, the microcomputer  411  also enables to record a data, a time, and a symbol for representing any one of the MPEG 1 -formatted data, the JPEG-formatted data, and the MPEG 1 -formatted data on a time when the recording switch  301  is pressed. At a time, the microcomputer  411  enables to record a symbol for representing a classification for retrieving the recorded data and a symbol for representing whether or not the operation of erasing the recorded data is prohibited. In recording the data, the classification symbol is recorded as “not classified” and the deletion symbol is recorded as “erasable”.  
         [0039]    In the general disk operating system, the symbol for indicating the imaging mode is discriminated using a code for a data type. The symbol for representing the classification and the symbol for representing if the data is erased are recorded in the corresponding files.  
         [0040]    On the other hand, when recording the data, a digital signal applied to the camera DSP  405  as a monitoring signal is converted into an analog TV signal through the effect of an NTSC or PAL encoder built in the circuit  405  and then is fed at an output terminal  416  and the built-in display unit  201 . The foregoing description has concerned with the MPEG 1 -formatted moving image data with the speech. In actual, the JPEG-formatted data or the MPEG 1 -formatted speech data may be solely processed in the similar manner to the above operation.  
         [0041]    When the system stays at the playback mode, the signal flows in an opposite manner to the flow at the recording mode. FIG. 16 is a flowchart showing the reproduction of the signal. Text data indicating information of data is read from the harddisk drive  415  (step  1601 ). Next, the user retrieves data from a list of data displayed on the built-in display unit  201  and specifies the data to be played back with the operating switch  408  (step  1604 ). The list of the recorded data displayed on the display unit  201  is a feature of the invention. With the specification, a file system is started (step  1605 ) so that the data is read out of the harddisk drive  415  and then sent to the microcomputer  411  (step  1606 ).  
         [0042]    Then, the data type is discriminated (steps  1607  and  1608 ). If the recorded data is the moving image, the MPEG-formatted moving image data and the MPEG-formatted speech data are both decoded (step  1609 ). If the recorded data is the still image, the JPEG-formatted still image data is decoded (step  1610 ). If the recorded data is the still image with the speech, the JPEG-formatted still image data and the MPEG-formatted speech data are both decoded (step  1611 ). Then, the decoded image and the decoded speech if any are displayed on the screen (step  1612 ).  
         [0043]    An indication signal issued by the operating switch  408  is read by a sub-microcomputer  407  and then is sent to the microcomputer  411  through a camera-controlling microcomputer  406 . The software program according to this embodiment is read out of a ROM  417  (Read-only Memory) for storing a program and then is executed. In this embodiment, the program is stored in the ROM  417 . In place of the ROM  417 , another storage unit such as a flash RAM or a harddisk drive may be used for the purpose.  
         [0044]    Next, the data is transferred to the buffer memory  412  through the PCMCIA connector  414  and the interface circuit  413 . The timing of the data stored in the buffer memory  412  is controlled by the microcomputer  411 . Then, the data whose timing is adjusted is sent to the MPEG 1  decoder  409 . The decoder  409  switches the MPEG 1  coding to the MPEG 1  decoding or vice versa.  
         [0045]    The data decoded by the MPEG 1  decoder  409  is sent to the camera DSP circuit  405  through the digital path line. The decoded data is converted into an analog video signal through the effect of an NTSC or PAL encoder and a DAC built in the circuit  405  and then is led at an output terminal  416  and from the built-in display unit  201  to the outside of the apparatus. The foregoing description has concerned with the MPEG 1 -formatted moving picture data with the speech. The JPEG-formatted still image data or the MPEG 1 -formatted speech data may be solely processed in the same manner as described above.  
         [0046]    The portable comcorder of this embodiment is arranged to use a harddisk unit of 260 MB for the harddisk drive  415 . In case that only the JPEG-formatted still image data is recorded, about 3000 still images may be recorded. In actual, the portable comcorder of this invention enables to retrieve 3000 items of data quickly and easily using the classifying function.  
         [0047]    [0047]FIG. 4 shows a circuit arrangement about the moving image. The corresponding circuit arrangement to that of FIG. 4 is required for the still images and the speech. That is, the portable camcorder of this embodiment is arranged to have a general-purpose means for imaging a moving object/a still object, a microphone, means for digitally converting a moving image/a still image, means for digitally converting speech, and means for digitally recording a moving image, a still image, and a speech signal.  
         [0048]    [0048]FIG. 5 shows the screen of the built-in display unit  201  used in the embodiment of the invention, in which the diagonal length is 1.8 inch (45.7 mm), the horizontal length is 36.6 mm, and the vertical length is 27 mm. The illustrated screen arrangement uses a liquid crystal consisting of 352 pixels and 240 pixels. In order to reduce the power consumption and the size of the portable digital camcorder  200 , the 1.8-inch liquid crystal is used for the built-in display unit  201 . This built-in display unit  201  shows an imaging screen formed by a monitoring signal when recording the signal, a retrieval screen formed by the program when retrieving the data, and a playback screen formed by the decoded data when playing back the data.  
         [0049]    In recording the data, the moving image recording mode (MPEG compression recording mode) or the still image recording mode (JPEG compression recording mode) may be switched each time the mode selecting button is pressed. As the user can select the recording mode with this button, as shown in FIGS. 17 and 18, the mark for each mode located in the upper left portion of the imaging screen is switched each time the mode is switched.  
         [0050]    [0050]FIG. 17 shows the imaging screen appearing when the still image recording mode is selected when recording data. In FIG. 17, a numeral  1701  denotes a mark representing a still image mode. FIG. 18 shows the imaging screen appearing when the moving image recording mode is selected when recording data. In FIG. 18, a numeral  1801  denotes a mark representing the moving image mode. The mark for each mode appears on the screen so that the user can visually recognize the current imaging mode as he or she is pushing the mode selecting button. This mark allows the user to handle the camcorder without having to keep his eyes out of the imaging screen. It means that the digital comcorder offers convenient operativity to the user.  
         [0051]    The mark for each mode is displayed on the retrieving screen through the effect of the program sent from a data containing unit. The retrieving screen will be discussed in detail together with the display of the mode mark. FIG. 19 shows the concrete mark for each mode. In actual, however, the marks are not limited to the illustrative ones. Any mark may be used if it can distinguish the modes from each other.  
         [0052]    In FIG. 5, the display screen  500  consists of 20× 9 characters at maximum, each character consisting of 16 and 24 pixels. The character size consisting of 16×24 pixels keeps the maximum recognizable size compatible with efficient digitizing of the character data. The blanks of a left side  501 , a right side  502 , an upper side  503 , and a lower side  504  of the screen are secured because the display unit or the built-in display unit  201  connected to an output terminal  416  disables to display the overall area of the main screen.  
         [0053]    A numeral  505  denotes an operating state display area where the operating state of the program of this embodiment is displayed. A numeral  506  denotes an area where the information of the recorded data and the functions to be operated for specifying the data details of the data by pressing a function switch  304  are displayed as individual items in partitioned sub-screens. A numeral  507  denotes an area where an operating procedure suggests the operating method to the user.  
         [0054]    [0054]FIG. 6 shows a display screen  600  appearing when a program starting switch  303  is pressed by the user for starting the program of this embodiment. The display screen  600  corresponds to a classifying selection  101  of FIG. 1 for indicating the state transition of the operation. As mentioned earlier, the data recorded by the user is unconditionally recorded “unclassified” when recording the data. The figure (number of files) displayed on the “unclassified” row stands for the number of MPEG 1 -formatted moving image data items with the speech  602 , the number of JPEG-formatted still image data pieces  603 , and the number of MPEG 1 -formatted speech  604 .  
         [0055]    Likewise, the figure displayed on each row of a mark  605  for indicating the first classification, a mark  606  for indicating the second classification, and a mark  607  for indicating the third classification indicate the numbers of data items arbitrarily classified by the user, respectively. A mark  608  for indicating all data items at a batch indicates the total number of the data items on the “unclassified” row  601 , the “first classified” row  605 , the “second classified” row  606 , and the “third classified” row  607 .  
         [0056]    A mark  609  for indicating the “temporary discard” means a classification for temporarily discarding the data items so that the user cannot erroneously erase the data items. With the mark  609 , the user can temporarily move the “unclassified”, “first classified”, “second classified”, and “third classified” data items to the “temporary discard” row. The figure represented on the row of the mark  609  does not contain a figure represented on the row of the mark  608  for indicating all data items at a batch.  
         [0057]    In FIG. 6, the row of the mark  601  for indicating the unclassification is reversed to the rows of the other marks. It indicates that the mark  601  for indicating the unclassification is the selected item. In place of the reversing, another kind of way may be used such as change of a color. The software program is executed by the user so that the recorded data items whose classifying destinations are not changed are contained in the row of the mark  601  for indicating the unclassification.  
         [0058]    When the upper arrow switch  305   a  of FIG. 3 is pressed by the user, the selected item is shifted upward by one row, while the lower arrow switch  305   c  is pressed, the selected item is shifted downward by one row.  
         [0059]    In case that the selected item is an item on the first row of the display area  506 , that is, on the mark  601  for indicating the unclassification, when the user presses the upper arrow switch  305   a , the selected item is shifted to the item on the sixth row of the display area  506 , that is, on the mark  609  for indicating the temporary discard. In case that the selected item is an item on the sixth row of the display area  506 , that is, on the mark  609  for indicating the temporary discard, when the user presses the lower arrow arrow  503   c , the selected item is shifted to the item on the first row of the display area  506 , that is, on the mark  601  for indicating the unclassification.  
         [0060]    When the user presses the right arrow switch  305   b , the display screen is shifted into the screen on which the content of the classification of the selected row is represented.  
         [0061]    Moreover, the guide indication  610  for the operating procedure is displayed so as to remind the user of the operation.  
         [0062]    As an example, FIG. 7 shows a display screen  700  on which the mark  605  for indicating the first classification is selected so that the data items on the row of the mark  605  appear as ones to be selected if the right arrow switch  305   b  is pressed by the user. This function corresponds to the data selection  102  shown in FIG. 1.  
         [0063]    The display screen  700  is a screen on which a data item is to be retrieved from a data list and played back. The data list is a feature of the present invention. On the screen  700 , the data items recorded by the portable digital camcorder  200  may be listed using a mark  703  for representing a sort of data content of a recording start time  702 , a moving image, a still image, and a speech, a classifying mark  704 , and a mark  705  for protecting data from being erased by the erroneous operation.  
         [0064]    The data items displayed on the screen  700  are ranged from the top to the down in the sequence of the recording year/month/day  701  and the recording start time  702 . Hence, the latest recorded data is listed on the topmost row, so that the user can effectively retrieve the data. The number of the pages of the displayed lists is checked, so that the lists are displayed as pages as indicated by a numeral  707 . In the page display  707 , a denominator indicates all the list pages, while a numerator indicates the current one of the list pages.  
         [0065]    The imaging status of the user such as the recording date and time and the data type are automatically recorded as the aforementioned information, so that the user can manually record these pieces of information. Since the user may optionally change the classifying destination according to his or her purpose, the user&#39;s retrieval work for the destination data is made simpler and more efficient.  
         [0066]    These pieces of information are all composed of a list represented in characters. This does not need a time consumed in expanding the compressed image data recorded on the media. Further, if the user selects a data item using the operating button, the screen can be rewound quickly, so that the quick retrieval is made possible.  
         [0067]    This list retrieving operation may offer comfortable operativity without having to impose stress on the user who wants to quickly select the recorded image.  
         [0068]    The selecting classification  706  indicates a classification selected by a display screen  600 . This embodiment has concerned with the user&#39;s selection of the first classification  605  on the display screen  600 .  
         [0069]    The display list of the data items on the display screens  700  and  800  is arranged in the sequence of recording the data on the harddisk drive  415 , that is, in the sequence that the latest data item comes to the topmost row. Since the user may change the sequence of recording the data items on the harddisk driver  415 , he or she may change the display sequence. The data immediately after imaging is recorded on the topmost row ( 701  of FIGS. 7 and 8) of the display area  506  on the unclassified data selecting screen. If the user makes sure of the just imaged data, he or she only reproduces the data and makes sure of the topmost row of the display area  506  on the unclassified data selecting screen.  
         [0070]    Like the display screen  600 , when the user presses the upper arrow switch  305   a , the selected data item is shifted upward by one row. When the user presses the lower arrow switch  305   c , the selected data item is shifted downward by one row. In this embodiment, the six rows of the data items are displayed on one screen. In case the user selects the sixth data item, if the lower arrow switch  305   c  is pressed, the seventh data item is displayed on the first row of the display area  506 . It means that the seventh data item is the selected item. The eighth, the ninth and the following data items are displayed on the second, the third, and the following rows, respectively.  
         [0071]    On the other hand, for example, in case the seventh data item is selected, if the upper arrow switch  305   a  is pressed, the seventh data item is displayed on the first row of the display area  506 . The second, the third, the fourth, the fifth, and the sixth data items are respectively displayed on the rows after the first one, so the selected data item is changed to the sixth data item.  
         [0072]    That is, the n-th data item is displayed on a remainder-th row on the display area  506 , in which the remainder is obtained by dividing n by 6.  
         [0073]    In case the head data item or the tail one is selected, if the upper arrow switch  305   a  or the lower arrow switch  305   c  is pressed, like the display screen  600 , the data items containing the head and the tail items are displayed as a list so that the head or the tail data item is selected. Though FIG. 6 shows the one-page screen on which the number of folders is fixed, FIGS. 7 and 8 show the screen on which the pages are increased or decreased in number according to the number of data items.  
         [0074]    If the user selects the upper arrow switch  305   a  and the lower arrow switch  305   c  shown in FIG. 3 and depresses the right arrow switch  305 , the selected data is fed out of the output terminal  416  and is played back on the built-in display unit  201 .  
         [0075]    While the data is being played back, the upper arrow switch  305   a , the lower arrow with  305   c , and the left arrow switch  30 , as shown in FIG. 3, are served as fast feed, rewind, and stop, respectively. While the data is being played back, if the left arrow switch  305   d  served as a stop switch is pressed by the user, the playback is stopped, and the display screen  700  is displayed again. The state transition during the data playback is denoted by a numeral  103  of FIG. 1.  
         [0076]    Next, the description will be oriented to the display content on which reduced images are added to the recording date and time so that the content of the data may be easily recognized. In the state of the display screen  700 , if the user presses the reduced image display switch  302 , a reduced image  801  of the first frame of the data listed on the subject row is displayed on the display screen  800  shown in FIG. 8. This makes it possible to surprisingly enhance the retrieval of the data. The state transition in the reduced image display function is denoted by a numeral  104  of FIG. 1.  
         [0077]    For example, in case that the viewable area of the 1.8-inch built-in LCD display unit  201  consists of 379 dots in horizontal and 220 dots in vertical, the reduced image  801  is adjusted to consist of 64 dots in horizontal and 48 dots in vertical. (if the LCD panel consists of 352 and 240 dots, the reduced image  801  consists of 240/48= 5 dots in vertical and 352/5= 70.4 in horizontal. From a vertical viewpoint, the reduced image is one-fifth and from a horizontal viewpoint, the reduced image is one-fifth with a slight margin.) In this reduction, three reduced images, the recording starting year month day  701 , the recording starting time  702 , the mark  703  representing the content type of the data indicating the moving image, the still image, and the speech, the classification mark  704 , and the mark  705  for protecting the data from being erroneously erased can be all displayed on one screen. This screen arrangement makes it possible to secure more visible reduced images on the display. Like the display screen  700 , on this display screen  800 , the data may be played back by pressing the operating button  305  and the like.  
         [0078]    In this state, if the reduced image display switch  302  is pressed again, the display screen is returned to the display screen  600  for displaying the data classification. The reduced image is depicted in the RAM  410  shown in the circuit block of FIG. 4 through the effect of the control microcomputer  411  and the MPEG encoder  409 .  
         [0079]    In turn, the description will be oriented to a function selecting display screen  900  for easily changing the display state from the data selecting display screen  700 . The function selecting display screen  900  includes the reduced number of operation switches and function items displayed thereon so that the ease of use in operation may be improved as viewing the screen. The operating switches  304 ,  305   a ,  305   b ,  305   c , and  305   d  shown in FIG. 3 implement the operating system for selectively operating the function. The state transition on the display screen  900  is denoted by a numeral  105  of FIG. 1.  
         [0080]    On the reduced image display screen  800 , the function selecting display screen  900  is displayed by the same procedure. On the display screen  600 , the display screen having the necessary functions such as “empty a garbage”, “move to a garbage”, “display a state”, and “auto play” shown in FIG. 1 is displayed by the same procedure. In this case, the function items on the display screen  900  are not required to be identical with the function items on the data classifying display screen  600 .  
         [0081]    The flow of operation on the display screen  900  is shown in FIG. 10. The display screen  900  is displayed when the user pressed the function switch  304  on the display screen  700  (step  1001 ). The selective movement of each item is indicated by the upper arrow switch  305   a  and the switch lower arrow switch  305   c . If the user pressed the upper arrow switch  305   a , the selected data item is moved upward by one row. If the lower arrow switch  305   c  is pressed, the selected data item is moved downward by one row (step  1002 ). If the user presses the right arrow switch  305   b  (step  1003 ), the function of the selected data item is executed (step  1004 ). If the left arrow function switch  305   d  is pressed, the display screen  900  is returned to the data selecting display screen  700  (step  1005 ).  
         [0082]    As mentioned earlier, in this embodiment, the erasion of the data is realized by moving the data to the temporary discard location and then erase the data contained in the temporary discard location. The state transition of this function is denoted by a numeral  106  of FIG. 1.  
         [0083]    The procedure of erasing the data will be described below.  
         [0084]    If the data is erased, the data is moved to the temporary discard location. In this case, the procedure for selectively executing “move the data to a garbage” will be described with reference to FIG. 9.  
         [0085]    At first, on the display screen  700 , the user selects the data item to be temporarily discarded with the upper arrow switch  305   a  and the lower arrow operating switch  305   c  and then depresses the function switch  304 . Then, the display screen  700  is changed to the display screen  900 . The user selects the “move data to a garbage”  901  with the upper arrow operation switch  305   a  and the lower arrow function switch  305   c  and then depresses the right arrow switch  305   b . Then, the selected data item is moved to the garbage that is the temporary discard location. If the user presses the switch  306 , the similarly selected data is moved to the garbage.  
         [0086]    When the user selects the “empty a garbage”  902  on the display screen  900 , all the data items left in the garbage are erased. The state transition of this function is denoted by a numeral  107  of FIG. 1.  
         [0087]    In the operating system, the user is required to do two operations for erasing the data. The two operations protect the data from the user&#39;s erroneous erasion.  
         [0088]    As mentioned earlier, when recording the data, the classifying symbol to be allocated to each data item is an unclassified one. When playing back the data, the classification may be changed by the user&#39;s operation. This classifying function is used for classifying the data item. Hence, since the user classifies the data item for each destination, the ease of use of the retrieval may be surprisingly enhanced. The state transition of this function is denoted by a numeral  108  of FIG. 1.  
         [0089]    Later, the description will be oriented to the procedure for changing the data classification. On the display screen  700 , the user selects the data item whose classification is to be changed with the upper arrow switch  305   a  or the lower arrow operation switch  305   c  and then presses the function switch  304 . Then, the display screen is changed to the display screen  900 . The user selects the “change a group”  905  that is a function of changing the classification with the upper arrow operation switch  305   a  and the lower arrow operation switch  305   c  and then presses the right arrow switch  305   b . Then, a display screen  1100  is displayed on which the classification of the selected data shown in FIG. 11 is changed.  
         [0090]    If the right arrow switch  305   b  is pressed on the display screen  1100 , the classification is cyclically changed from “unclassification” to 1 to 2 to 3 to “unclassification”. In this embodiment, the update of the symbol for the classification according to the display screen is executed by the control microcomputer  411  at a time when the user presses the left arrow switch  305   d  and the display screen  600  appears. This is intended for enhancing the processing speed and retrying the user&#39;s operation.  
         [0091]    As described earlier, unless the user does the following operation, the list indicated on the display screen  700  is arranged in the recording sequence of the recorded data. When playing back the data, the sequence may be changed so as to implement a simple editing function. The state transition of this function is denoted by a numeral  109  of FIG. 1.  
         [0092]    The procedure of changing the data displaying sequence will be described below. At first, on the display screen  700 , the user selects the data item whose displaying sequence is to be changed with the upper arrow switch  305   a  and the lower arrow switch  305   c . Then, if the function switch  304  is pressed, the display screen  900  is displayed.  
         [0093]    The user selects the “change a data display sequence”  906  that is a function of changing the display sequence with the lower arrow switch  305   c  and depresses the right arrow switch  305   b . Then, the display screen  1200  shown in FIG. 12 is displayed, so that the display sequence of the selected data item may be changed. Next, the user specifies the location where the selected data is to be inserted with the upper arrow switch  305   a  and the lower arrow switch  305   c . Then, if the right arrow switch  305   b  is pressed, the selected data item is inserted to the specified location. In this case, the sequence of the data item located after the specified location is shifted lower by one.  
         [0094]    The portable digital camcorder  200  of this embodiment incorporates an internal clock for displaying on the display screen  700  the date and the time when the data is recorded. However, if failure such as run-down of a battery takes place while imaging an object, the recorded data and time may not be correctly displayed on the display screen  700 . In this embodiment, the user may operate to optionally change the date and time when the data is recorded. The state transition of this function is denoted by a numeral  110  of FIG. 1.  
         [0095]    Later, the description will be oriented to the procedure for changing the date and time. The user selects the data whose recording date and time are to be changed using the upper arrow switch  305   a  and the lower arrow switch  305   c . Then, if the function switch  304  is pressed, the display screen  900  is displayed. The user selects the “change a recording date and time”  907  that is a function of changing the displaying sequence with the upper arrow switch  305   a  and the lower arrow switch  305   c . Next, if the right arrow switch  305   b  is pressed, the display screen  1300  shown in FIG. 13 is displayed where the recording date and time of the selected data are to be changed.  
         [0096]    In this state, when the user pressed the upper arrow switch  305   a , the year FIG. 1301 is increased by 1, while the lower arrow switch  305   c  is pressed, the year FIG. 1301 is decreased by 1. When the right arrow switch  305   b  is pressed, the year FIG. 1301 is determined as a numeric value represented at the time point. Next, the user may specify the increment or decrement of the numeric value of a month FIG. 1302.  
         [0097]    Likewise, if the upper arrow switch  305   a  is pressed, the month FIG. 1302 is increased by 1, while if the lower arrow switch  305   c  is pressed, the month figure  1302  is decreased by 1. If the right arrow switch  305   b  is pressed, the month FIG. 1302 is determined as a numerical value displayed at the time point. Next, the user may specify the increment or decrement of a numerical value of a day FIG. 1303.  
         [0098]    Further, when the left arrow switch  305   d  is pressed, the year FIG. 1301 may be retried. The similar operation may be executed to set the day FIG. 1303, an a.m or p.m. indication  1304 , a time FIG. 1305, and a minute FIG. 1306. After adjusting a value of the minute FIG. 1306, if the right arrow switch  305   b  is pressed, the change of the recording date and time is terminated and the date and time of the data is changed to a new numeric value.  
         [0099]    In the case of specifying an numeric value that does not exist in the calendar such as February 30, the numeric value is changed to the nearest date (that is, March 1) to the value.  
         [0100]    In this embodiment, though the user can freely erase the data, the user may provide the data with an attribute of prohibiting the erasion for preventing the data from being erased. The state transition of this function is denoted by a numeral  111  of FIG. 1.  
         [0101]    Later, the description will be oriented to the procedure for adding the attribute of protecting the data from the erasion to the data. At first, on the display screen  700 , the user selects the data whose erasing attribute is to be changed with the upper arrow switch  305   a  or the lower arrow switch  305   c . Then, the function switch  304  is pressed, so that the display screen  700  is changed to the display screen  900 . The user selects the “change a lock”  904  that is a function of changing the erasing attribute with the upper arrow switch  305   a  or the lower arrow switch  305   c . Then, if the right arrow switch  305   b  is pressed, the display screen  1400  is displayed where the erasing attribute of the selected data shown in FIG. 14 is changed.  
         [0102]    When the user pressed the right arrow switch  305   b , the erasing attribute is cyclically changed from “disabled” to “enabled” to “disabled”. The protecting mark  705  is displayed or not displayed according to the erasing attribute.  
         [0103]    In this embodiment, the user can know the remaining volume of the harddisk drive  415 . The state transition of this function is denoted by a numeral  112  of FIG. 1.  
         [0104]    Hereafter, the description will be oriented to the procedure for checking the remaining volume of the harddisk drive  415 . On the display screen  700 , if the user presses the function switch  304 , the display screen  700  is changed to the display screen  900 . The user selects the “display a state”  903  that is a function of changing the displaying sequence with the upper arrow switch  305   a  or the lower arrow switch  305   c . Then, if the right arrow switch  305   b  is pressed, the display screen  1500  is displayed where the remaining volume of the harddisk drive  415  shown in FIG. 15 is shown.  
         [0105]    On the display screen  1500 , a remaining time  1501  left if only the MPEG 1 -formatted moving image data with the speech is recorded on the harddisk drive  415 , a remaining pages left if only the JPEG-formatted still image data is recorded, a remaining time  1503  left if only the MPEG 1 -formatted speech data is recorded, and a remaining volume  1504  represented in bytes are all displayed as a list. Since the remaining volume of the harddisk drive is listed with respect to each recordable data type, the user can more easily grasp the remaining volume of the harddisk drive  415 .  
         [0106]    In this embodiment, when playing back the data, the user needs to use only the switches  305   a ,  305   d ,  305   c  and  305   d  for playing back the data. It is epoch-making that the minimum number of operating switches are just required for playing back the data.  
         [0107]    Another epoch-making point is the increase of the functions without increasing the operating buttons by using the functional selecting screen  900 .  
         [0108]    In this embodiment, as shown in FIG. 6, the classified number of data items is four including “unclassified”. The classified number of data may take any value. On the data selecting display screen  700 , the data items may be displayed as a list independently of the types of the moving image, the still image, and the speech. This embodiment may apply to the function of automatically classifying the data according to the data type with the user&#39;s specification.  
         [0109]    Moreover, the control microcomputer  411  is operated to automatically select the data according to the imaging modes such as the moving image and the still image. For example, the user can select only the imaging mode for the still image, pick up only the image type of the still image, and reproduce it.  
         [0110]    The foregoing description has been concerned with the specific embodiments of the invention. The present invention may apply to the following arrangement.  
         [0111]    For example, the present invention may be achieved by an image recording apparatus which includes converting means for converting a video signal into a digital signal, a codec unit for selectively performing a MPEG system or a JPEG system compression about the digital signal, for generating the compressed data, a recording unit for recording the compressed data, and a selective indicating means for a compression mode, for selectively indicating the MPEG system compression or the JPEG system compression.  
         [0112]    This image recording apparatus may be applicably arranged to switch the compressing system of the codec unit according to the indication given by the selective indicating means.  
         [0113]    Further, the image recording apparatus may be applicably arranged to add a code for indicating the compression system to the compressed data according to the indication given by the selective indicating means.  
         [0114]    Further, the image recording apparatus may be applicably arranged so that the codec unit may be a circuit for performing the MPEG system and the JPEG system processing at one process.  
         [0115]    Moreover, the image recording apparatus may be applicably arranged so that the video signal is obtained from an imaging element and the recording unit is a harddisk drive.  
         [0116]    The present invention may be also achieved by the image reproducing apparatus which includes a recording unit for receiving compressed data generated according to the MPEG system or the JPEG system and recording the compressed data, specifying means for specifying a data item to be reproduced of the compressed data recorded in the recording unit, readout means for retrieving and reading out the compressed data specified by the specifying means from the recording unit, a codec unit for selectively performing the MPEG system or the JPEG system expansion about the compressed data and generating the digital signal, and converting means for converting the digital signal generated by the codec unit into a video signal.  
         [0117]    Moreover, the image reproducing apparatus may be applicably arranged so that the expanding system of the codec unit may be switched according to the compressed data read out of the readout means.  
         [0118]    Further, the image reproducing apparatus may be applicably arranged so that the compressed data of the recording unit pre-contains the code indicating the compressing system and the expanding system of the codec unit may be switched according to the code for indicating the compressing system added to the compressed data read out of the readout means.  
         [0119]    Further, the image reproducing apparatus may be applicably arranged so that the codec unit may be a circuit for performing the MPEG system and the JPEG system expansion at one process, the video signal is output to the built-in display unit, and the recording unit may be a harddisk drive.  
         [0120]    The present invention may be achieved by the image recording and reproducing apparatus for converting a video signal into a digital signal, recording the digital signal, converting the digital signal into the video signal, and reproducing the video signal, which includes a codec unit for selectively performing the MPEG system or the JPEG system compression about the digital signal for generating the compressed data in recording the data and selectively performing the MPEG system or the JPEG system expansion about the compressed data for generating the digital signal in reproducing the data, a recording unit for recording the compressed data, selective indicating means for the compressing mode for selectively indicating the MPEG system compression or the JPEG system compression, specifying means for specifying the data to be reproduced of the compressed data recorded in the recording unit, and readout means for retrieving and reading the compressed data specified by the specifying means from the recording unit.  
         [0121]    Moreover, the image recording and reproducing apparatus may be applicably arranged so that the codec unit may switch the compressing system according to the indication given by the selective indicating means in recording the data or the expanding system according to the compressed data read out of the readout means in reproducing the data.  
         [0122]    Further, the image recording and reproducing apparatus may be applicably arranged so that in recording the data, the recording unit adds the code for indicating the compressing system to the compressed data according to the indication given by the selective indicating means and records the compressed data and in reproducing the data, the codec unit switches the expanding system according to the code for indicating the compressing system added to the compressed data read out of the readout means.  
         [0123]    Moreover, the image recording and reproducing apparatus may be applicably arranged so that the codec unit may be a circuit for performing the MPEG system and the JPEG system processing at one process, the video signal to be recorded is obtained from an imaging element, the video signal to be reproduced is output to the built-in display unit, and the recording unit is a harddisk drive.  
         [0124]    As described above, as keeping the capacity of the recording medium larger and advancing the compressing technology, the data items to be recorded on one recording medium are increased in number. This embodiment, however, makes it possible to do the recording and the reproducing operations with quite few keys. Hence, this embodiment offers the below-indicated effects, so that it may improve the operativity even if it is applied to the small-sized apparatus with a limited space prepared for the operation buttons or switches.  
         [0125]    This embodiment may display the recording date and time information and the marks for modes such as the moving image, the still image, and the still image with the speech as a list. Hence, the user can efficiently and quickly retrieve the data as grasping the content of the data. In recording the data, the marks are switchably displayed on the imaging screen each time the mode is switched so that the user can grasp the current imaging mode. Hence, the user can focus his or her attention onto the imaging screen at any mode when recording the data.  
         [0126]    The display list is composed of a date and a time. The apparatus of this embodiment may automatically create the overall list and at once output the reduced images, so that the user can more easily grasp the content of the data.  
         [0127]    The imaged data may be classified to the predetermined locations. Hence, the imaged data may be classified on the mode information and the date and time information according to the imaging statue and the object. This classification makes it easier for the user to retrieve the data.  
         [0128]    Further, the displaying sequence of the list and the generating sequence of the data are allowed to be replaced depending on the mode information and the date and time information. Hence, the optimal reproducing effect can be obtained without having to depend on the recording sequence.  
         [0129]    Then, the classification of “temporary discard” is provided for preventing the erasion of the data resulting from the user&#39;s erroneous operation and reusing the unnecessary data if it is made necessary after being deleted.  
         [0130]    As described above, if the operation on the relatively simple graphic screen is executed to record a great deal of data, the function of this embodiment enables to offer quicker retrieval than the conventional function of reproducing the data as expanding all image screens.