Abstract:
An optical disk recording device providing disks adapted for direct access reproduction and a direct access reproducing method thereof. A recording location of a disk at a user-selected direct access unit time or a user-selected time point is stored as a reproduction starting address. Prepared pictures or pictures selected by a user during recording data on the disk are recorded as choice menus on the disk. A direct access table is generated in which reproduction starting addresses are cross-referenced with recording locations of the choice menus. The direct address table is recorded in a specific area of the disk. During reproduction, the direct access table is read and the choice menus are read from the disk according to the recording locations of the choice menus included in the direct access table. A direct access menu picture is generated and displayed. Data at a recording location of the disk corresponding to the reproduction starting address of a user-selected choice menu is reproduced in response to a user&#39;s selection.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of Korean Application No.1997-80567 which is hereby incorporated by reference. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to an optical disk system, and in particular, to a device and method for recording or reproducing information on or from an optical disk. 
     With an optical disk recording device, information, such as a movie, can be recorded on a recordable optical disk such as a DVD-R (Digital Video Disk Recordable) or a DVD-RAM (Digital Video Disk Random Access Memory). When a user records a movie for continuous reproduction with an optical disk reproducing device, only continuous reproduction is possible, i.e., direct access to a specific part of the movie is not possible. To allow the user to reproduce data in a manner with allows direct access to a specific part of the disk, an optical disk recording device must simultaneously record and edit the information in cooperation with a computer using a storage means such as a hard disk. As can be imagined, such a recording procedure is a great inconvenience and cannot be performed in real time. Currently, it is impossible for a user to easily record information in such a way that he may directly access data on an intended location of the disk during reproduction. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to provide an optical disk recording device which can record data on an optical disk in such a way that a user can reproduce the data while enjoying direct access to a selected location of the disk. 
     Another object of the present invention is to provide a direct access reproducing method which allows a user to reproduce data while enjoying direct access to a selected location of an optical disk. 
     Additional objects and advantages of the invention will be set forth in part in the description which follows, and, in part, will be obvious from the description, or may be learned by practice of the invention. 
     Objects of the invention are achieved in an optical disk recording device for direct access reproduction in which a recording location on a disk, at a user-selected direct access unit time or a user-selected time point, is stored as a reproduction starting address. Prepared pictures or pictures selected by a user, while recording data on the disk, are recorded as choice menus on the disk. A direct access table is created, in which reproduction starting addresses are matched with the recording locations of the choice menus. The direct access table is recorded at a specific area of the disk. 
     Objects of the present invention are also achieved in a direct access reproducing method comprising reading a direct access table in a direct access reproduction mode, reading choice menus from the disk according to the recording locations of the choice menus included in the direct access table, displaying a direct access menu picture, and reproducing data, at the recording location of the disk, corresponding to the reproduction starting address of a user-selected choice menu. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above objects and advantages of the present invention will become more apparent and more readily appreciated from the following description of the preferred embodiments with reference to the accompanying drawings in which: 
     FIG. 1 is a block diagram of an optical disk recording device for producing disks adaptable for direct access reproduction according to a first embodiment of the present invention; 
     FIG. 2 is a flowchart of the operation of a microcontroller, shown in FIG. 1, according to the first embodiment of the present invention; 
     FIG. 3 is a block diagram of an optical disk recording device for producing disks adapted for direct access reproduction according to a second embodiment of the present invention; 
     FIG. 4 is a flowchart of the operation of a microcontroller, shown in FIG. 3, according to the second embodiment of the present invention; 
     FIG. 5 is a flowchart of the operation of the microcontroller, shown in FIG. 3, according to a third embodiment of the present invention; 
     FIG. 6 is a block diagram of an optical disk reproducing device according to a fourth embodiment of the present invention; 
     FIG. 7 is a flowchart of the operation of a microcontroller, shown in FIG. 6, according to the fourth embodiment of the present invention; and 
     FIG. 8 is a diagram of choice menus for use with direct access reproduction according to the preferred embodiments of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Though certain particular details such as structure or flowchart are disclosed in description of the present invention and corresponding drawings for comprehensive understanding of the subject matter of the present invention, they are merely exemplary. A detailed description of known functions and structures used in the present invention has been omitted if such description is well known to one of ordinary skill in the art and such disclosure obscures the subject matter of the present invention. 
     Reference will now be made in detail to the present preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. 
     FIG. 1 is a block diagram of an optical disk recording device for producing disks adapted for direct access reproduction according to a first embodiment of the present invention. The optical disk recording apparatus generally comprises: a general optical disk recording/reproducing apparatus (described hereinafter) with the addition of a switch  114 , a memory  126 , a timer  128 , and a random number generator  130 . The optical disk recording device of FIG. 1 is so constituted that when a user is recording a movie, to be reproduced with direct access, in predetermined time periods, for example ten minutes from the moment when the movies plays, different pictures, each corresponding to the beginning of a time period, are created and stored as different choice menus. During playback, data from a corresponding reproduction time period is directly accessed upon when a user selects a specific choice menu. 
     FIG. 8 is a diagram of choice menus for direct access reproduction according to the preferred embodiments of the present invention. FIG. 8 only shows one of many possible configurations and screen displays. One of ordinary skill in the art will realize that the exact configuration and screen display will be dictated by the specific implementation of the invention. Choice menus  802 ,  804  and  806  are displayed in a menu picture  800  so that a recording position can be selected for direct access reproduction. Each choice menu corresponds to one of a plurality of time periods predetermined time set in units, for example ten minutes. 
     Referring once again to FIG. 1, an optical pickup  102  records data on a disk  100  using a light source driven by a laser driver  120 . The light source preferably is a semiconductor laser, such as laser diode. This optical pickup  102  includes a focusing actuator (not shown) and a tracking actuator (not shown). The focusing actuator moves an object lens of the optical pickup  102  along an optical axis direction under control of a servo processor  122 , while the tracking actuator moves the object lens of the optical pickup  102  along the radial direction of the disk  100  to search for a track, under control of a servo processor  122 . A spindle motor  104  rotates the disk  100  at a constant linear velocity (CLV) under control of the servo processor  122 . A sled feed motor  106  transfers the body of the optical pickup  102  under the control of the servo processor  122 . The servo processor  122 , which controls the focusing and tracking actuators of the optical pickup  102 , the spindle motor  104 , and the sled fed motor  106 , are in turn ultimately controlled by a microcontroller  124 , such as a microprocessor. 
     An audio encoder  108  encodes audio data for placement on the disk  100 . A video encoder  110  encodes video data for placement on the disk  100 . A mixer  112  mixes the outputs of the audio encoder  108  and the video encoder  110 . The switch  114  selects between the outputs of the mixer  112  and the memory  126  and outputs the selected data to a channel encoder  116  under the control of the microcontroller  124 . The channel encoder  116  channel-encodes the output of the switch  114  and outputs the channel-encoded data in the form of bit streams, to a laser driver  120  for recording on the disk  100 . 
     Generally, in the channel encoder  116 , the output of the switch  114  is encoded with an address on the disk  100 , that is, an ID (Identification), and an ID correction parity. The encoded output is then subjected to scrambling, that is, addition of an error detection parity, has an additional data error correcting parity, and is finally {fraction (8/16)}-modulated and outputted. The modulated output, in bit stream format, of the channel encoder  116  is applied to the laser driver  120 . The memory  118  functions as a data storage for the channel encoder  116  during processing. The laser driver  120  optically modulates the bit streams received from the channel encoder  116  and applies the optically modulated data to the optical pickup  102  so that the light source of the optical pickup  102  is driven to record the bit streams on the disk  100 . 
     The memory  126  stores video data for a plurality of pictures. The memory  126  outputs video data of a picture corresponding to an address designated by the microcontroller  124  to the switch  114 . The timer  128  generates an interrupt signal upon passage of a unit time preset by the microcontroller  124  (for example 10 minutes) and applies the interrupt signal to the microcontroller  124 . The random number generator  130  generates random numbers included in addresses of the memory  126  and applies the random numbers to the microcontroller  124 . A key input portion  132 , such as an IR remote control, keyboard, input pad, or even a mouse, provides a key input of a user to the microcontroller  124 . 
     FIG. 2 is a flowchart illustrating the operation of the microcontroller  124  according to the first embodiment of the present invention. When a user wants to record data, such as a movie, on the disk  100 , using the optical disk recording device of FIG. 1, adapted for direct access during reproduction, he selects a direct access reproduction recording mode using the key input portion  132 . The user selects a direct access time interval for using during playback, calculated from a reproduction starting point using the key input portion  132 . 
     Then in step  200 , the microcontroller  124  sets the user-selected direct access unit time received from the key input portion  132  in the timer  128 . In a loop at step  202 , the microcontroller  124  waits for data recording to be initiated. When data starts to be recorded on the disk  100 , the operation goes to step  204  and the microcontroller  124  activates the timer  128 . Subsequently, in a loop at step  206 , the microcontroller  124  waits for an interrupt signal to be generated by the timer  128 . The timer  128  generates an interrupt signal upon passage of every direct access unit time from the recording starting point and applies the interrupt signal to the microcontroller  124 . 
     Every time the timer  128  generates an interrupt signal, the operation goes to step  208  and the microcontroller  124  stores the current recording location of the disk  100  as a reproduction starting address, in step  208 . Subsequently, in a loop at step  210 , the microcontroller  124  checks whether recording is completed. If recording is not completed, the procedure returns to step  206 . 
     Once recording is completed on the disk  100  (through repeated implementation of steps  206  through  210 ), the operation goes to step  212  and the microcontroller  124  sequentially reads the video data of pictures corresponding to random numbers generated by the random number generator  130  and records the video data as choice menus on the disk  100 . Basically, the switch  114  selects the output of the mixer  112  and applies the selected data to the channel encoder  116  while data is being recorded, and subsequently provides the output of the memory  126  to the channel encoder  116  under the control of the microcontroller  124  when recording is completed. The pictures stored in the memory  126  by a manufacturer of the optical disk recording device shown in FIG. 1 are provided as choice menus during a subsequent direct access reproduction, see FIG.  8 . 
     Following recording of the video data of the choice menus on the disk  100 , the operation goes to step  214  and the microcontroller  124  generates a direct access table in which the reproduction starting addresses stored in step  208  are matched with the recording locations of the choice menus on the disk  100 . Next, in step  216 , the microcontroller  124  sends the direct access table to the channel encoder  116  to be recorded at a specific area on the disk  100 . The specific area may be, for example, a lead-in area of the disk  100 . An exemplary direct access table is shown in Table 1. 
     
       
         
               
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                   
                 Recording Location of Choice 
                 Reproduction Start Address 
               
               
                 Index 
                 Menu on Disk 
                 Designated by Choice Menu 
               
               
                   
               
             
             
               
                 INDEX 1 
                 MENU ADDR. #1 
                 PLAY ADDR. #1 
               
               
                 INDEX 2 
                 MENU ADDR. #2 
                 PLAY ADDR. #1 
               
               
                 INDEX 3 
                 MENU ADDR. #3 
                 PLAY ADDR. #1 
               
               
                 . 
                 . 
                 . 
               
               
                 . 
                 . 
                 . 
               
               
                 . 
                 . 
                 . 
               
               
                 INDEX n 
                 MENU ADDR. #4 
                 PLAY ADDR. #1 
               
               
                   
               
             
          
         
       
     
     Table 1 also contains a reproduction starting address representative of the recording location of data recorded at a designated time corresponds to the recording location of a choice menu. Using the direct access table a user can reproduce data, with direct access to an intended recording location, by selecting a choice menu, as is described hereinafter. 
     Although the first embodiment of the present invention has been described with respect to a specific configuration, it will be recognized that the first embodiment is not limited to the specific configuration. For example, while the pictures for the choice menus have been disclosed as being randomly selected, they could be preselected by the user or interactively selected by the user during recording. 
     FIG. 3 is a block diagram of an optical disk recording device for producing a disk adapted for direct access reproduction according to a second embodiment of the present invention. Here, the random number generator  130  of FIG. 1 is omitted in favor of an address generator  134 . Additionally, the output of the video encoder  110  is also applied to the memory  126 . In the optical disk recording device shown in FIG. 3, pictures for choice menus are not prestored in the memory  126 , as described in FIG.  1 . Rather, the video data from the movie, input and recorded at a unit time period, selected by a user after a movie to be recorded starts, is stored in the memory  126  and used as a choice menu. This offers the advantage in that the picture for direct access reproduction in a unit time period is copied from the movie as a choice menu. Thus, the user can select a direct access reproduction location with feeling of being connected to the movie. The address generator  134  generates a storage address in the memory  126  under the control of the microcontroller  124 . 
     FIG. 4 is a flowchart showing the operation of the microcontroller  124  shown in FIG. 3 according to the second embodiment of the present invention. When a user wants to record data, such as a movie, on the disk  100  using the optical disk recording device shown in FIG. 3, the user selects a direct access reproduction recording mode using the key input portion  132 . For playback of the data, the user selects a direct access time interval calculated from a reproduction starting point as a direct access unit time using the key input portion  132 . 
     Then, in step  400 , the microcontroller  124  sets the user-selected direct access unit time received from the key input portion  132  in the timer  128 . Subsequently, in a loop at step  402 , the microcontroller  124  waits for data recording to be initiated. When data recording starts in step  402 , the operation goes to step  404  and the microcontroller  124  activates the timer  128 . Then, in a loop at step  406 , the microcontroller  124  waits for an interrupt signal to generate in the timer  128  in a loop at step  406 . The timer  128  generates an interrupt signal upon passage of every direct access unit time from the recording starting point and applies the interrupt signal to the microcontroller  124 . 
     Every time the timer  128  generates an interrupt signal, the microcontroller  124  stores the current recording location of the disk  100  as a reproduction starting address, in step  408 . Thereafter, the microcontroller  124  stores the video data of the currently recorded picture in the memory  126  by designating an address by the address generator  134 . At this time, the video data of the currently recorded picture is stored in the memory  126  by the video encoder  110 . 
     Then, in a loop at step  412 , the microcontroller  124  checks whether recording is completed. When recording is not completed, the procedure returns to step  406 . Once recording is completed on the disk  100  (through repeated implementation steps  406  through  412 ), the operation goes to step  414  and the microcontroller  124  sequentially reads the video data of pictures from the memory  126  and records the video data as choice menus on the disk  100 . Basically, the switch  114  selects the output of the mixer  112  and applies the selected data to the channel encoder  116  while data is being recorded, and subsequently provides the output of the memory  126  to the channel encoder  116  under the control of the microcontroller  124  when recording is completed. Then, in step  416 , the microcontroller  124  generates a direct access table, for example, as shown in Table 1, in which the reproduction starting addresses stored in step  408  corresponds with the recording locations of the choice menus on the disk  100 . In step  418 , the microcontroller  124  applies the direct access table to the channel encoder  116  to be recorded at a specific area on the disk  100 . 
     Although the second embodiment of the present invention has been described with respect to a specific configuration, it will be recognized that the second embodiment is not limited to the specific configuration. For example some pre-defined image processing could be applied to the recorded picture prior to storage on the optical disk  100 . 
     FIG. 5 is a flowchart illustrating the operation of the microcontroller  124  according to a third embodiment of the present invention. Here, a user manually and interactively sets a direct access reproduction time point at which the video data of the movie is input and stored with at the time point as a choice menu in the memory  126 . This is to be compared to the flowcharts shown of FIGS. 2 and 4 in which a direct access time interval is predetermined. 
     When a user wants to record data like a movie on the disk  100  using the optical disk recording device, shown in FIG. 3, he selects a direct access reproduction recording mode using the key input portion  132 . Here, a direct access time interval is not selected, instead, the user selects the picture at an intended time point during recording, which obviates the need of the timer  128  shown in FIG.  3 . 
     The microcontroller  124  waits, in a loop at step  500  for data recording to be initiated (in response to the selection of the recording mode for direct access reproduction). When recording starts on the disk  100  in step  500 , the operation goes to step  502  and the microcontroller  124  waits for the user to select a picture (menu choice) in step  502 . When the user selects a picture at an intended time point in step  502 , the operation goes to step  504  and the microcontroller  124  stores a recording location at the time point as a reproduction starting address. In step  506 , the microcontroller  124  stores the video data of the currently recorded picture in the memory  126  by designating an address using the address generator  134 . The video data of the currently recorded picture is stored in the memory  126  from the video encoder  110 . Then, in step  508 , the microcontroller  124  checks whether recording is completed. If recording is not over, the procedure returns to step  502 . 
     When recording is completed on the disk in step  508  (through repetition of steps  502  through  508 ), operation goes to step  510  and the microcontroller  124  sequentially reads the video data of pictures from the memory  126  and records the video data as choice menus on the disk. Basically, the switch  114  selects the output of the mixer  112  and applies the selected data to the channel encoder  116  while data is being recorded, and subsequently applies the output of the memory  126  to the channel encoder  116  under the control of the microcontroller  124  when recording is completed. In step  512 , the microcontroller  124  generates a direct access table, for example, as shown in Table 1, in which the reproduction stating addresses stored in step  506  matches with the recording locations of choice menus on the disk  100 . Next, in step  514 , the microcontroller  124  sends the direct access table to the channel encoder  116  to be recorded at a specific area on the disk  100 . 
     Although the third embodiment of the present invention has been described with respect to a specific configuration, it will be recognized that the third embodiment is not limited to the specific configuration. For example, a combination of the second and third embodiments is envisioned in which controller is responsible to both the times and the user in setting locations in the movie for choice menus. 
     FIG. 6 is a block diagram of an optical disk reproducing device for reproducing the optical disks masted by any of the foregoing optical disk recording devices, forming a fourth embodiment of the present invention. In FIG. 6, a spindle motor  604 , a sled feed motor  606 , and a servo processor  628  correspond to the spindle motor  104 , the sled feed motor  106 , and the servo processor  122  shown in FIG. 1, respectively. A key input portion  632  serves a similar function (discussed hereinafter) but does not necessarily have a similar configuration to the key input portion  132 . 
     An optical pickup  602  optically picks up data recorded on a disk  600 , generates an electrically converted RF (Radio Frequency) signal, and outputs the RF signal to an RF amplifier  608 . The RF amplifier  608  amplifies the RF signal received from the optical pickup  602 , corrects the wave of the amplified RF signal, and outputs bit streams for recording to a channel decoder  610 . The channel decoder  610 , under control of a microcontroller  630 , demodulates the bit streams received from the RF amplifier  608  and corrects errors in the bit streams to recover data, and outputs the recovered data to a parser  614 . A memory  612  serves as a data storage for the channel decoder  610 . 
     The parser  614  applies the recovered audio and video data to the audio and video decoders  616  and  618 , respectively. The audio decoder  616  decodes the audio data and outputs the decoded audio data to a digital-to-analog converter (DAC)  620 . The DAC  620  converts the audio data to an analog signal and applies the analog signal to a speaker  624 . The video decoder  618  decodes the video data and outputs the decoded video data to an NTSC (National Television System Committee) encoder  622  for display on a monitor  626 . Of course, the NTSC encoder  622  corresponds to the standard for which a monitor  626  is used. A PAL encoder or any other appropriate encoder, such as an HDTV encoder, can be used. Thus, audio and video data reproduced from the disk  600  is output via the speaker  624  and the monitor  626 , respectively. 
     FIG. 7 is a flowchart illustrating the operation of the microcontroller  630  shown in FIG. 6 according to the fourth embodiment of the present invention. When a user selects a direct access reproduction mode of an optical disk  600  using the key input portion  632  (such as an IR remote control), the operation starts in step  700  and microcontroller  630  reads the direct access table, for example, as shown in Table 1 from the disk  600 . In step  702 , the microcontroller  630  reads choice menus from the disk  200  according to the recording locations of the choice menus included in the direct access table. In a loop comprising steps  704  and  706 , the microcontroller  639  waits for the user to select a choice menu through the key input portion  632 , displaying the choice menus in a direct access menu picture. Here, the time corresponding to the recording location of each choice menu is displayed together with the choice menu, as shown in FIG.  8 . 
     When, in step  706 , the user selects one of the choice menus in the direct access menu picture, the operation goes to step  708  and microcontroller  630  reproduces data at the recording location of the disk  100  corresponding to the reproduction starting address of the selected choice menu. The operation then waits in step  710  until the data is completely reproduced, and the operation is completed in step  710 . 
     As described above, data is recorded on a disk in such a way that data at an intended location can be directly accessed and reproduced. From such a disk, a user can reproduce data with direct access to a specific intended location of the disk. 
     Although the fourth embodiment of the present invention has been described with respect to a specific configuration, it will be recognized that the fourth embodiment is not limited to the specific configuration. Once of ordinary skill in the art will recognize that there any many possibilities for a user interface, other than those shown in FIG.  8 . Any such interface may be used as long as the user is presented with the stored choice menus. 
     Although a few preferred embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents. While the present invention has been described in detail with reference to the specific embodiments, they are merely exemplary applications. Thus, it is to be clearly understood that many variations can be made by anyone skilled in the art within the scope and spirit of the present invention. For example, although the direct access table is recorded in the lead-in area of a disk in the embodiments of the present invention, the location of the direct access table is not confined to the lead-in area. In addition, the direct access table may be recorded by a seller who records necessary data on a disk, not by a user. Further, the present invention has been described with particular emphasis on audio/visual data representing movies. However, one of ordinary skill in the art will recognize that various embodiments of the present invention are also applicable to other types of data to be sequentially reproduced, such as: audio, slide shows, presentations, number sequences, and animation.