Patent Publication Number: US-7225310-B2

Title: Method for successively recording data in hybrid digital recorder

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a method for successively recording data in a hybrid digital recorder, and more particularly to a method for successively recording long-term broadcast program data on a plurality of optical discs in a hybrid digital recorder in which a DVD recorder and an HDD recorder are integrated. 
   2. Description of the Related Art 
     FIG. 1  is a block diagram illustrating a conventional hybrid digital recorder. For example, a hybrid digital recorder in which a DVD recorder and an HDD recorder are integrated includes an optical disc  10 , an optical pickup unit  11 , a Video Disc Recording (VDR) system  12 , an HDD  13 , a Hard Disc Recording (HDR) system  14 , a microprocessor  15 , and a switch  16 , etc. 
   The microprocessor  15  controls the HDR system  14  according to a user&#39;s request when recording an external input data stream such as a long-term broadcast program, and records the external input data stream in the HDD  13 . The microprocessor  15  may also record the external input data stream on a rewritable DVD (DVD-RW) by controlling the VDR system  12 . In this case, the microprocessor  15  controls the switch  16  to enter the external input data stream in the HDR system  14  and/or the VDR system  12 . 
   For example, in the case of recording a long-term broadcast program broadcast during 3 hours on the condition that a data stream broadcast during 2 hours can be recorded on a single DVD-RW disc, a user must replace a current optical disc with a new optical disc if 2 hours has elapsed while the broadcast program is recorded on the current optical disc. 
   However, a predetermined time (e.g., a time of about 20 seconds and over) is required for the user to replace the current optical disc with the new optical disc, such that a broadcast program is not successively recorded and a broadcast data stream corresponding to an important scene may be lost. 
   In the case of recording a long-term broadcast program broadcast in real time in an HDD of a predetermined device, the recorded broadcast program can actually be reproduced by only the predetermined device, such that a user who desires to reproduce the broadcast program using another device at a predetermined location must recopy the broadcast program recorded in the HDD on an optical disc such as a DVD-RW disc, resulting in greater inconvenience of use. 
   SUMMARY OF THE INVENTION 
   Therefore, the present invention has been made in view of the above problems, and it is an object of the present invention to provide a method for dividing an external input data stream such as a long-term broadcast program into a plurality of data units, distributing the divided data units to a plurality of optical discs, and successively recording the data units on the optical discs, respectively, without generating any lost data, in a hybrid digital recorder in which a DVD recorder and the HDD recorder are integrated in one body. 
   In accordance with one aspect of the present invention, the above and other objects can be accomplished by a method for successively recording data in a hybrid digital recorder, comprising: recording an input data stream on a detachable recording medium; temporarily storing the input data stream in a predetermined memory when the recording medium has no redundant area in which the data stream can additionally be recorded; if the recording medium is replaced with a new recording medium, while temporarily storing the input data stream in the predetermined memory, reading the data stream temporarily stored in the memory, and recording the read data stream on the new recording medium; and recording a data stream input afterward on the new recording medium, if the data stream temporarily stored in the memory is read and recorded on the new recording medium. 
   In accordance with another aspect of the present invention, there is provided a hybrid digital recorder apparatus for successively recording data therein, comprising: a drive for recording an input data stream on a detachable recording medium; a memory for storing the input data stream; and a controller for controlling the drive and the memory such that it temporarily stores the input data stream in the memory when the recording medium has no redundant area in which the data stream can additionally be recorded, if the recording medium is replaced with a new recording medium, while temporarily storing the input data stream in the memory, reads the data stream temporarily stored in the memory and records the read data stream on the new recording medium, and records a data stream input afterward on the new recording medium if the data stream temporarily stored in the memory is read and recorded on the new recording medium. Preferably, the hybrid digital recorder apparatus may further include an On Screen Display (OSD) generator for generating an image including information associated with a recording state of the hybrid digital recorder apparatus, and displaying the generated image on an external display. 
   Preferably, a recording speed at which the data stream temporarily stored in the memory is read and recorded on the new recording medium is higher than a transfer rate of the input data stream. 
   Preferably, the controller calculates the remaining time during which the input data stream can additionally be recorded on the basis of a transfer rate of the input data stream and a redundant area of the recording medium, and displays the calculated remaining time on the external display. 
   Preferably, the controller calculates a disc replacement time on the basis of a transfer rate of the input data stream, a redundant area of the memory, and a recording speed at which the data stream temporarily stored in the memory is recorded on the new recording medium, and displays the calculated disc replacement time on the external display. 
   Preferably, the method may further comprise: disregarding a user-entry recording stop command or a user-entry power-off command if no data stream is input before all the data streams temporarily stored in the memory are recorded on the new recording medium, and recording all the data streams temporarily stored in the memory before being recorded on the new recording medium on the new recording medium. 
   Preferably, the recording medium is indicative of an optical disc, and the memory is indicative of either a Hard Disc Drive (HDD) or a detachable flash memory card and a memory card drive. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which: 
       FIG. 1  is a block diagram illustrating a conventional hybrid digital recorder; 
       FIG. 2  is a block diagram illustrating a hybrid digital recorder according to the present invention; 
       FIG. 3  is a flow chart illustrating a method for successively recording data in a hybrid digital recorder according to the present invention; and 
       FIG. 4  is an exemplary graph illustrating a method for recording data on an optical disc or HDD. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   Now, preferred embodiments of the present invention will be described in detail with reference to the annexed drawings. In the drawings, the same or similar elements are denoted by the same reference numerals even though they are depicted in different drawings. In the following description, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear. 
     FIG. 2  is a block diagram illustrating a hybrid digital recorder according to the present invention. For example, a hybrid digital recorder in which a DVD recorder and an HDD recorder are integrated includes an optical disc  20 , an optical pickup unit  21 , a VDR system  22 , an HDD system  24 , a microprocessor  25 , a switch  26 , and an input buffer  27 , etc. 
   The above-mentioned hybrid digital recorder may further include an On Screen Display (OSD) generator  28 . The input buffer  27  temporarily stores an external input data stream. The microprocessor  25  controls the switch  26  to enter the data stream temporarily stored in the input buffer  27  in the VDR system  22  or the HDR system  24 . 
   The microprocessor  25  controls the VDR system  22  upon receipt of a request from a user, and records the external input data stream (e.g., a broadcast program) temporarily stored in the input buffer  27  on the optical disc  20 . In this case, if the optical disc  20  is full of data due to the long-term broadcast program, the microprocessor  25  uses the HDD  23  as a large-capacity buffer, such that it performs a successive data recording operation in which the long-term broadcast program is successively recorded on a plurality of optical discs without generating any lost data. 
     FIG. 3  is a flow chart illustrating a method for successively recording data in a hybrid digital recorder according to the present invention. Referring to  FIG. 3 , the microprocessor  25  establishes a successive record mode of data according to a user request signal at step S 10 , and determines whether a user request for commanding the external input data stream such as a broadcast program to be recorded on an optical disc such as a DVD-RW disc is received at step S 11 . Upon receipt of the above-mentioned user request, the microprocessor  25  controls the switch  26  to enter the external input data stream temporarily stored in the input buffer  27  in the VDR system  12 . 
   The VDR system  22  performs signal processing of converting the above-mentioned external input data stream into a signal suitable for a recording operation, such that it records the signal-processed data stream on the optical disc  20  at step S 12 . The microprocessor  25  determines whether a recording capacity of the optical disc  20  is full of data at step S 13 . 
   If it is determined that the recording capacity of the optical disc is full of data at step S 13 , the microprocessor  25  controls the switch  25  to enter the external input data stream temporarily stored in the input buffer  27  in the HDR system, and at the same time controls the HDR system  24  to allow the HDD  23  to act as a large-capacity buffer, such that the above-mentioned input data stream is temporarily stored in a specific area of the HDD  23  at step S 14 . 
   Thereafter, the microprocessor  25  determines whether a user replaces a current optical disc with a new optical disc at step S 15 . In the case where the new optical disc (e.g., Disc  2 ) is inserted into the hybrid digital recorder and is completely loaded on the same, the microprocessor  25  maintains a current switching state of the switch  26  to enter the external input data stream temporarily stored in the input buffer  27  in the HDR system  24 . Also, the microprocessor  25  controls the HDR system  24  such that it successively and temporarily stores the above-mentioned input data stream in the HDD  23 . Further, the microprocessor  25  controls the VDR system  22  to read a data stream stored in the HDD  23 , and records the read data stream on the new optical disc (i.e., Disc  2 ) at a high speed at step S 16 . 
   In this case, a data recording speed of the optical disc must be higher than an HDD recording speed, i.e., a transfer rate of the external input data stream, as shown in  FIG. 4 . Therefore, it is preferable that the data recording speed of the optical disc is determined to be a maximum speed at which the VDR system  22  and the new optical disc (i.e., Disc  2 ) can stably record desired data thereon. 
   In the meantime, the microprocessor  25  performs a temporary storage operation of the HDD  23  and a high-speed recording operation for the new optical disc, and at the same time monitors whether the external input data stream temporarily stored in the HDD  23  is completely read or not at step S 17 . In this case, a transfer rate V a  of the external input data stream, a time t g  taken to insert the new optical disc (Disc  2 ) into the hybrid digital recorder and complete a initial loading operation of the inserted optical disc after a recording capacity of the optical disc  20  has entered a full state, a recording speed V b  at which the data stream temporarily stored in the HDD  23  is recorded on the new optical disc (Disc  2 ), and a time t s  during which all the data streams temporarily stored in the HDD  23  are read and completely recorded on the new optical disc (Disc  2 ) after replacing a current optical disc with the new optical disc (Disc  2 ) satisfy the following equation V a ×(t g +t s )=V b ×t s , such that the resultant value of t s  is determined to be 
   
     
       
         
           
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   If all the data streams temporarily stored in the HDD  23  are read, the microprocessor  25  controls the switch  26  to enter the external input data stream temporarily stored in the input buffer  27  in the VDR system  22 , and directly records the above-mentioned input data stream on the new optical disc without using the HDD  23  at step S 18 . In this case, there is no need for a recording speed of the optical disc to be equal to a high speed, and it is preferable that the recording speed of the optical disc is determined to be a transfer rate of the external input data stream. 
   In the meantime, the microprocessor  25  records the input data stream on the optical disc  20  by controlling the VDR system  22 , and at the same time calculates the remaining time during which the above-mentioned input data stream can additionally be recorded on the optical disc  20 . The microprocessor  25  calculates the remaining time on the basis of a transfer rate of the input data stream and a redundant area of the optical disc  20 . The microprocessor  25  controls the OSD generator  28  to generate caption data including the calculated remaining time and display the caption data on a screen of a display such as a TV, such that the user can perform a disc replacement preparation for replacing a current optical disc with the new optical disc. 
   Provided that a predetermined recording capacity of the optical disc  20  is full of data on the condition that the redundant area of the HDD  23  is insufficient, and a user does not rapidly replace a current optical disc with the new optical disc, the input data stream is not successively recorded on the new optical disc and some parts thereof may be unavoidably lost. To reduce the probability of the above-mentioned problems, the microprocessor  25  calculates a predetermined time at which the user must replace the current optical disc with the new optical disc after the recording capacity of the current optical disc is full of data, and displays the calculated time on a TV screen, such that the user can previously recognize the predetermined time before the recording capacity of the current optical disc is full of data. 
   The microprocessor  25  can calculate a disc replacement time t g  on the basis of a transfer rate V a  of the input data stream, a redundant area Q h  of the HDD  23 , and a recording speed V b  at which the data stream temporarily stored in the HDD  23  is recorded on the optical disc to be replaced with the new one. In  FIG. 4 , the redundant area Q h  of the HDD  23  is represented by Q h =V b ×t s , and the time of t s  during which all the data streams temporarily stored in the HDD  23  are read and completely recorded on the new optical disc after replacing the current optical disc with the new optical disc is represented by 
               t   s     =         V   a       (       V   b     -     V   a       )       ×     t   g         ,         
such that the disc replacement time t g  can be represented by
 
             t   g     =         (       V   b     -     V   a       )         V   a     ×     V   b         ×       Q   h     .             
In this case, the microprocessor  25  displays a value less than the calculated disc replacement time t g  in consideration of a time required for initial operations, such as servo and Optical recording Power Calibration (OPC) operations, to be performed after the new optical disc is inserted into an optical disc drive.
 
   In the meantime, if the broadcasting of a broadcast program is terminated before all the data streams temporarily stored in the HDD  23  are recorded on the new optical disc, the user determines that the recording of the broadcast program is terminated, such that the user may stop the recording operation of the hybrid digital recorder or may power off the hybrid digital recorder. In order to prevent the user from stopping the recording operation of the hybrid digital recorder or from powering off the hybrid digital recorder, the microprocessor  25  disregards the user-entry recording stop command or the user-entry power-off command, and records all the data streams (Q r ) temporarily stored in the HDD  23  without being recorded on the new optical disc on the new optical disc during a predetermined time of t r =Q r /V b . Thereafter, the microprocessor  25  may stop the recording operation of the hybrid digital recorder, or may power off the hybrid digital recorder. 
   The above-mentioned method for successively recording data according to the present invention is applicable to a variety of hybrid devices other than the above-mentioned hybrid digital recorder. In other words, the hybrid digital recorder shown in  FIG. 2  may also be indicative of a detachable flash memory card (e.g., a Security Digital (SD) card, a Compact Flash (CF) card, or Memory Stick, etc.) and a memory card drive for reading data from the flash memory or recording data in the flash memory. 
   As apparent from the above description, the present invention can efficiently record a long-term broadcast program such as a broadcast data stream on a plurality of optical discs in a successive manner. 
   Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.