Abstract:
A recording medium, a method and an apparatus for managing text data and main data are provided. The method includes recording text data in a text data file separate from a file containing main data associated with the text data, recording navigation information that links the main data and the text data, and recording, in the text data file, attribute information associated with the text data.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a data managing method that records lyrics associated with recorded audio data in a file separated from audio data management information called RTR_AMG (Real Time Record Audio Management) allocated in a rewritable recording medium, and that searches for a lyric unit written in the separate file prior to reproducing the recorded audio data. 
   2. Description of the Related Art 
   A disk-type recording medium such as a Compact Disk (CD) can store high-quality digital audio data permanently, so that it is very popular recording medium in these days. 
   Recently, a Digital Versatile Disk (called ‘DVD’ hereinafter) has been developed as a new disk-type recording medium. A DVD can store much larger size than a CD, that is, high-quality moving pictures or audio data are recorded in a DVD for much longer time. Therefore, a DVD will be used widely in the near future. 
   There are three types in a DVD, DVD-ROM for read-only, DVD-R for write-once, and DVD-RAM or DVD-RW for rewritable. For a rewritable DVD, the standardization of data writing format is in progress. 
     FIG. 1  is a block diagram of an optical disk device that records/reproduces audio data to/from a recording medium. 
   The disk device configured as  FIG. 1  comprises an optical pickup  11  reading signals recorded in a rewritable DVD  10  such as a DVD-RW and writing data streams processed into writable signals onto the rewritable DVD  10 ; a reproduced signal processor  12  restoring the read signals into compressed digital data; a decoder  13  decoding the compressed digital data to original data; a sampler  18  digitizing an inputted analog signal at a preset sampling rate; an encoder  17  encoding the digitized LPCM data into MPEG-, or AC3-formatted data; a writing processor  16  converting the encoded data from the encoder  17  or LPCM data from the sampler  18  into signals suitable to be written; a controller  14  controlling all elements to conduct user&#39;s command such as playback or record; and a memory  15  for storing data temporally. 
   If an analog signal is applied to the disk device of  FIG. 1 , the sampler  18  samples the analog signal at the preset sampling rate. Each sampled signal, which is LPCM data, is applied to the encoder  17  that encodes a block of sampled data into compressed data of pre-specified format, for example, MPEG format. The compressed data are then applied to the writing processor  16 . 
   The writing processor  16  converts a series of the compressed data into binary signals which are written in mark/space patterns on the writable DVD  10 . Already-compressed digital data from outside are directly processed by the writing processor  16  to be written onto the writable DVD  10 . 
   After recording of audio data, navigation data for them are created and then recorded the writable DVD  10 . 
     FIG. 2  shows the structure of RTR_AMG (Real Time Record Audio ManaGement) recorded as navigation data on a rewritable disk. The RTR_AMG includes RTR_AMGI (RTR Audio Manager General Information), AUDFIT (AUDio File Information Table), ASVFIT (Audio Still Video File Information Table), ORG_PGCI (ORiGinal PGC (ProGram Chain) Information), UD_PGCIT (User Defined PGC Information Table), TXTDT_MG (TeXT DaTa ManaGer), and MNFIT (MaNufacturer&#39;s Information Table). 
   The TXTDT_MG can include lyrics of recorded songs. Therefore, when the controller  14  selects and reproduces a recorded song from the rewritable disk  10 , it is able to present lyric text in characters on a screen by reading it from the TXTDT_MG. 
   Consequently, when a user selects a recorded song to play back from the rewritable DVD  10 , he or she is able to view its lyric on a screen. 
   By the way, the size of RTR_AMG including the TXTDT_MG may be restricted below a certain limit, e.g., 512 KBytes for the purpose of saving resources of a disk player. Furthermore, because an MP3 audio file, which is relatively small in size by lossy coding, is about 2˜4 Mbytes in size, a DVD-RW of about 4.7 GBytes in storage capacity is able to store more than about 1,000 MP3 audio files. Thus, if all lyrics of such many recorded MP3 audio files were written in the TXTDT_MG, the size of RTR_AMG including TXTDT_MG would exceed by far the size limitation. 
   SUMMARY OF THE INVENTION 
   It is an object of the present invention to provide a data managing method that records lyrics associated with recorded audio data in a file separated from RTR_AMG allocated in a rewritable recording medium and records search information in the RTR_AMG to refer to respective lyrics in the separate file in order that a lyric may be easily found prior to reproducing corresponding audio data. 
   It is another object of the present invention to provide another data managing method that reproduces audio data and lyric data in the separate file that are pointed by the search information in RTR_AMG. 
   A method of managing lyrics for audio data recorded on a rewritable disk in accordance with the present invention records lyric data of audio data recorded on a rewritable recording medium in a file separated from management information for the recorded audio data, and records in the management information search information to point to respective lyric data of the recorded audio data. 
   A method of reading lyrics for audio data recorded on a rewritable disk in accordance with the present invention reads management information for reproduction control of recorded audio data, and searches a file, separated from the management information, for lyric data based on the read management information. 
   These and other objects of the present application will become more readily apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention, illustrate the preferred embodiments of the invention, and together with the description, serve to explain the principles of the present invention. 
     In the drawings: 
       FIG. 1  is a block diagram of an optical disk device that records/reproduces audio data to/from a recording medium; 
       FIG. 2  shows the structure of RTR_AMG (Real Time Record Audio ManaGement) recorded as navigation data on a rewritable disk; 
       FIG. 3  shows an RTR_AMG including an ALFIT (Audio Lyric File Information Table) according to an embodiment of the present invention; 
       FIG. 4  shows cell information including an audio lyric unit search pointer number according to an embodiment of the present invention; 
       FIG. 5  shows cell information including an audio lyric unit search pointer number and the number of the search pointer numbers according to another embodiment of the present invention; 
       FIG. 6  shows a structure of an ALFIT in RTR_AMG including information to point to individual audio lyric units in an audio lyric file; 
       FIG. 7  shows another structure of an ALFIT in RTR_AMG including information to point to individual audio lyric units in an audio lyric file; 
       FIG. 8  shows a schematic procedure to find an audio lyric unit related with a selected song; and 
       FIG. 9  shows program information including an audio lyric unit search pointer number according to another embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   In order that the invention may be fully understood, a preferred embodiment thereof will now be described with reference to the accompanying drawings. 
   In an audio data recording method in accordance with the present invention, after small-sized audio data such as an MP3 audio file, which is relatively small in size by lossy coding, is recorded onto a rewritable disk of large capacity, a lyric related with a recorded song is recorded in a specific file named, e.g., ‘AR_Lyric.ARO’ that is separated from a management information file, namely, RTR_AMG file. Then, search information to point to respective lyrics in the separate file is recorded in the RTR_AMG. 
     FIG. 3  shows an RTR_AMG including an ALFIT (Audio Lyric File Information Table) according to an embodiment of the present invention. 
   The RTR_AMG of  FIG. 3  includes RTR_AMGI, ASVFIT, ORG_PGCI, UD_PGCIT, TXTDT_MG, and MNFIT the same as  FIG. 2 . However, the RTR_AMG further includes an ALFIT. 
   The ORG_PGCI is composed of PGC_GI (PGC General Information), plural pieces of PGI ‘PGI # 1 ˜#m’, a plurality of CI_SRPs (Cell Information SeaRch Pointers), and plural pieces of CI (Cell Information) ‘CI # 1 ˜#n’, as shown in  FIG. 4 . Each CI includes cell type information ‘C_TY’, playback information ‘PB_INF’, an AOBI_SRPN (AOB Information SeaRch Pointer Number) for indexing information location of a related AOB (or an MP3-formatted song), an ASVUI_SRPN (ASVU (Audio Still Video Unit) Information SeaRch Pointer Number) for indexing information location of still video data linked with an AOB, and an ALUI search pointer number ‘ALUI_SRPN’ for indexing a corresponding ALUI search pointer among pointers in the ALFIT. 
   The ALUI search pointer number ‘ALUI_SRPN’ is indicative of an index number of an ALU (Audio Lyric Unit) search pointer in the ALFIT that has location information of an ALU written in the separate file ‘AR_Lyric.ARO’ 
   The CI may be structured differently.  FIG. 5  shows another structure of CI. The CI of  FIG. 5  is to accommodate plural ALUI search pointer numbers. This is useful for writing several lyric languages for a single song. An ALU allocated in the file ‘AR_Lyric.ARO’ can contain user data entered by user inputs, instead of lyric text of an associated song. 
   If CI is related with an EMD (Electronic Music Distribution) data file of which data are uniquely formatted, the cell type ‘C_TY’ identifies that an EMD file is related. In this case, the CI includes no information related with lyric such as the fields ‘ALUI_SRPN’. 
     FIG. 6  shows the structure of the ALFIT in RTR_AMG. The ALUI_SRPN in CI indexes an ALU search pointer in the ALFIT, as aforementioned. 
   The ALFIT is composed of ALFITI (ALFIT Information) and ALFI. The ALFITI includes fields of ‘ALFI_Ns’ reserved for the number of audio lyric information files, ‘AL_I_Ns’ for the number of pieces of audio lyric information, and ‘ALFIT_EA’ for an end address of ALFIT. 
   The ALFI is composed of ALFI_GI (ALFI General Information) and a plurality of ALUI (Audio Lyric Unit Information) search pointers, each includes ‘ALU_SA’ for a start address of a lyric unit, ‘ALU_SZ’ for size of a lyric unit, and ‘L_ATR’ for attribute of a lyric text. 
   The ALU_SA in each ALUI search pointer points to location of a corresponding ALU (Audio Lyric Unit) in the specific file ‘AR_Lyric.ARO’ that is separated from the RTR_AMG, as shown in  FIG. 6 . Each ALU in the file ‘AR_Lyric.ARO’ includes a lyric text associated with a single recorded song. 
   Thus, if a song, namely, an AOB is chosen, a disk player reads the number written in ALUI_SPRN of CI associated with the selected AOB, and specifies an ALUI search pointer contained in the field ‘ALFI’ by the read number. The location of a lyric unit related with the selected song is found in the file ‘AR_Lyric.ARO’ by location address in the specified pointer. Therefore, lyric text can be presented along with reproduced audio data. 
   The disk player may process the read lyric text based on the lyric attribute written in the field ‘L_ATR’ of the current ALUI search pointer. In other words, if the attribute is indicative of a certain language, the disk player converts the lyric text written in the lyric unit to characters of corresponding language font. The lyric attribute field can be allocated in a lyric unit in the file ‘AR_Lyric.ARO’ instead of in the ALFIT, as shown in  FIG. 7 . 
   Under the condition that RTR_AMG and the lyric file ‘AR_Lyric.ARO’ are constructed as described above, a lyric related with a selected song, namely, audio data is found through the search information in RTR_AMG as follows and then presented along with the selected audio data. 
     FIG. 8  shows a schematic procedure to find an ALU related with a selected song. 
   The controller  14  of the disk device of  FIG. 1  searches the ORG_PGC of RTR_AMG for a piece of PGI and/or a piece of CI that is associated with a recorded song selected by a user. If a user selects a program chain including a plurality of recorded songs, the controller  14  searches the ORG_PGI for a piece of PGI and/or CI associated with the first song of them. 
   Further, the controller  14  checks the field ‘C_TY’ in the found CI to know whether the associated audio data have been encoded to special EMD format. 
   If not EMD-formatted, the controller  14  reads the numbers written in AOBI_SRPN and ASVUI_SRPN of CI associated with the selected AOB, namely, song, and reproduces recorded audio data indexed by the number in AOBI_SRPN and still video unit indexed by the number in ASVUI_SRPN. The still video unit is presented in a series of still pictures. 
   At the same time, the controller  14  reads the number written in ALUI_SRPN of that CI, and then specifies an ALUI search pointer contained in the ‘ALFIT’ of RTR_AMG by the read number. The controller  14  examines three fields ‘ALU_SA’, ‘ALU_SZ’, and ‘L_ATR’ included in the specified ALUI search pointer. 
   The location of a lyric unit related with the selected song is found in the file ‘AR_Lyric.ARO’ by the address written in the ‘ALU_SA’. Lyric text is read into the memory  15  from that location as size as the ‘ALU_SZ’ specifies. The read text is processed to an adequate language based on lyric attribute defined by the field ‘L_ATR’. Consequently, the processed lyric is presented onto a screen during playback of the selected audio data. 
   If the lyric attribute is allocated in a lyric unit as shown in  FIG. 7 , the controller  14  processes the lyric text based on the lyric attribute written therein to present into adequate language. 
   If a plurality of ALUI search pointer numbers have been recorded in a single piece of CI, the controller  14  selects only one ALUI_SRPN among them based on user&#39;s selection or selects them sequentially. In latter case, lyric units are sequentially presented in the same sequence that the ALUI search pointer numbers are placed. 
   If the cell type is indicative of EMD format, the controller  14  executes a decoding algorithm suitable for that format to play back the selected song. 
   The type field indicating type of audio data and the number field ‘ALUI_SRPN’ can be allocated in PGI instead of in CI, as shown in  FIG. 9 , because a piece of PGI is also assigned to a single program, namely, AOB. In this case, type field allocated in PGI is called program type ‘PG_TY’. 
   The above-explained lyric data managing method for a rewritable disk of large storage capacity can accommodate the entire lyrics of many small-sized songs recorded on a rewritable disk without any increment of the size of RTR_AMG over a given size limitation. Consequently, the system requirement of a disk device is alleviated to manage recorded audio data. 
   The detailed description of the invention has been directed to certain exemplary embodiments, various modifications of these embodiments, as well as alternative embodiments, will be suggested to those skilled in the art. The invention encompasses any modifications or alternative embodiments that fall within the scope of the claims.