|Title of Invention||
"A MULTIMEDIA DATA STORAGE DEVICE, REPRODUCTION APPARATUS AND A MULTIMEDIA DATA RECORDING METHOD"
|Abstract||A multimedia data reproducing apparatus, and multimedia data storage include a first layer storing multimedia data; and a second layer in which, when the multimedia data is divided into a record unit and a reproduction unit, information of attributes of the record unit and a relationship between the record unit and the reproduction unit are described with a markup language using elements and the attributes. Navigation data, which is used to control a selection of the reproduction unit and reproduction sequence, is recorded on a third layer.|
|Full Text||Technical Field
The present invention relates to recording and reproducing multimedia data, and more particularly, to apparatuses to record and/or reproduce multimedia data using a hierarchical information structure and an information storage medium thereof.
A multimedia data recording/reproducing apparatus requires additional information, such as attributes of multimedia information or a sequence of data reproduction, to record the multimedia infomnation on or to reproduce the multimedia information from a data storage medium. FIG. 1 illustrates the conventional multimedia data recording/reproducing apparatus 200 including the data storage medium 100 and connected to a user output device 300. The multimedia data recording/reproducing apparatus 200 may be controlled using a user input device 400, such as a remote control. In general, in order to record the additional information, additional information tables are formed at a particular position or in a particular file of the existing data storage medium. Examples of the data storage medium include compact discs (CDs), video CDs, and digital versatile discs (DVDs). In the additional information table, information is described by a location and a length of a data field. Thus, a new information table needs to be created whenever a new type of multimedia information medium is designed, in particular, navigation information, to select a reproduction unit or to determine the reproduction sequence, is recorded in table formats on the DVD. However, such navigation information is mixed with the information that defines reproduction units, thereby making it difficult to carry out a
The data structure of a conventional DVD will now be described. Referring to FIG. 2, a DVD includes a video manager (VMG) area and a plurality of video title set (VTS) areas. Control information and title selection information are stored in the VMG area, where the title information of a reproduction unit is stored in the plurality of VTS areas. The VMG area includes two or three files and each VTS area includes three to twelve files.
The VMG area is illustrated in FIG. 3 in detail. The VMG area includes a video manager information (VMGI) area to store the additional information regarding the VMG area, a video object set (VOBS) area to store video object information of a menu, and a VMGI backup area. Each of the above areas includes a single file. The VOBS area may or may not be included in the VMG area, but the other two areas, the VMGI area and the VMGI backup area, are required.
Title information and VOBS are stored in the VTS area. A plurality of titles may be recorded in the VTS area. The VTS area is illustrated in detail in FIG. 4.
Referring to FIG. 4, video title set information (VTSI), the VOBS for menu, which is a video object set for the VTS menu, VOBS for title, which is the video object set for the titles in a VTS, and VTSI backup data are recorded in VTS area #n. However, the VOBS for the title may not be included in VTS area #n. Each VOBS is divided into a video object (VOB) on cells, which are recording units. Each VOB includes the cells. According to an aspect of the present invention, the cell is determined to be a lowest-ranked unit of data.
A reproduction unit is represented by a hierarchical structure in which a title is present at a corresponding top level. The title includes one program chain (PGC) or a plurality of PGCS linked to one another.
Here, a first PGC is called an entry PGC. FIG. 5 illustrates the reproduction unit one_sequential_PGC_title, including only a single PGC (an entry PGC). FIG. 6 illustrates the reproduction unit in which the title is linked to the plurality of PGCs. After reproduction of the PGC, another PGC is reproduced by selecting from at least one of several PGCs. In this case, a selection command may be stored in program chain information (PGCI). Controlling the sequence of PGC reproduction is called the navigation. FIG. 7 illustrates the structure of the PGC. The PGC is stored in an information structure described as a PGCI format. The PGCI includes a pre-command in which navigation commands are stored, a post-command, and a plurality of program information units. The pre-command is carried out before the reproduction of a related PGC and the post-command is carried out after the reproduction of the PGC. Each program information unit includes a plurality of cell information units, each cell linked to the cell in the VOB, which is the recording unit. Each cell included in each reproduction unit has a cell command that is carried out after reproduction of the cell. Therefore, the PGCI represents a hierarchical reproducing structure of the PGC, i.e., the reproduction unit, in which the lowest-ranked reproduction unit cell is linked to the lowest-ranked record unit cell.
FIG. 8 illustrates a case of branching a new PGC using command navigation information during or after reproduction of the PGC. In other words, it is possible to easily control the sequence of the PGC reproduction using navigation commands such as LinkPrevPGC, LinkTopPGC, LinkNextPGC, LinkTailPGC, LinkGoUpPGC, and LinkPGCN. That is, the PGC has reproduction units and also navigation information.
A program in the PGC is referenced by a link called a part of title (PTT).
In the case of the DVD, the above information is stored in a binary table format, that is, the information is recorded in table formats where the information is recorded within a predetermined bit length on a particular position of the table.
FIG. 9 illustrates a data structure of a TT_SRPT information table, which is title information in the VMGI. Referring to FIG. 9, the leading two bytes of the TT_SRPT information indicates a total number of titles n. The next two bytes of the TT_SRPT information is reserved for extension information defined in a future standard. The other bytes following the two bytes represent TT_SRP information that individually describes the titles. In particular, a VTN number, designated by a related title, and a title number in a related VTS are recorded with predetermined bit lengths on certain positions of VTSN and VTS_TTN, respectively.
FIG. 10 illustrates a data structure of VTS_PTT_SRPT information in the VTSI. Referring to FIG. 10, the VTS_PTT_SRPT information includes TTU_SRPs corresponding to a number of the titles of the related VTS. The respective TTU_SRPs include information to designate one of the PTT_SRPs following the TTU_SRPs. Therefore, a PTT_SRP between a PTT_SRP, which is designated by a TTU_SRP, and a PTT_SRP, which is designated by a next TTU_SRP, form the title. That is, a plurality of Part_of_Title Search Pointers PTT-SRPs are present in each title, resulting in a division of the title into several PTTs. The PTT may be viewed as a chapter, for easier understanding. FIG. 11 illustrates contents of the PTT_SRP, designating the PGC and a program in the PGC. In conclusion, the title is divided into several PTTs and each PTT is linked to a program in the PGC.
FIG. 12 illustrates a data structure of a PGCIT VTS_PGCIT, representing a PGCI table in the VTSI. Referring to FIG. 12, a total number of the programs and the cells that belong to the PGC are stored
in a VTS_PGCITI. Also, the VTS_PGCIT stores VTS_PGCis as many as a plurality of \/TS_PGCs, which belong to the VTS. FIG. 13 illustrates a detailed data structure of the VTS_PGCI. In the VTS_PGCI, various information are recorded within particular bit lengths at particular positions in table formats, including a PGC_CMDT, which describes a pre-command, a post-command, a cell command, and so on. Also, the VTS_PGCI includes a PGC_PGMAP, which indicates program start cells as many as the programs, and a C_POSIT, which is the information for linkage of respective cells to respective record units.
As described above, in the case of the conventional DVD, which is a multimedia data storage medium, the video object data and the data regarding the reproduction units and the navigation are recorded as the titles and the PGCs. However, the additional data in the PGCs is stored in the table format within particular lengths at a certain position. The commands to navigate are also stored in a limited space, together with the additional data, which define reproduction units. Therefore, the advent of a new reproduction unit results in a change of the table location; thus, making it difficult to implement an extension for the new reproduction. To solve this problem, reserved spaces are formed in a plurality of regions, which still limits any extension for the future. In the worst-case scenario, a table structure may be redefined. In fact, existing multimedia data storage media such as the CDs, the VCDs, the MDs, and the DVDs have table structures of their own.
Meanwhile, advancements in Internet technologies trigger development of personal computers (PCs) capable of processing multimedia. For instance, video object data or audio data may be inserted into a document with HyperText Markup Language (HTML) or may be reproduced during reproduction of HTML. In this case, the navigation data is described with a script language or the like. Therefore, the navigation data may be described separate from reproduction data. If there are two types of navigation data, e.g., one
controlled using script language and another one described in the table format, it is complicated to control both types of navigation data.
Disclosure of the Invention
According to an aspect of the present invention, there is provided a data storage medium and a data reproduction apparatus. Assuming that the data reproduction apparatus operates as specified in the present invention, a recording apparatus records information, according to the data structure of which is specified in the present invention, and multimedia data on a storage medium. Here, storing operations are understood as identical to recording operations.
Multimedia data and additional data are recorded in a storage medium, according to an aspect of the present invention. The present invention suggests separate recording of two different types of additional data: additional information regarding record units, attributes, and reproduction units of the multimedia data, and navigation information regarding selection of a reproduction unit and a reproduction sequence. The additional information regarding a record unit, attributes, or a reproduction unit, with respect to multimedia data, is described using a markup language. Accordingly, implementation supporting an extension of a future standard is possible even when adding a new type of multimedia data or prescribing a new type of recording or reproduction unit, regardless of the standard adopted. Alternatively, the additional information may be stored in a binary table format.
Also, both or one of a markup language and a script language may be used to describe navigation data, which represents selection of a reproduction unit or reproduction sequence. A markup language is also used to describe presentation data, which represents a menu screen to select a reproduction unit and a screen layout for data reproduction,
thereby enabling a menu structure and navigation with a high degree of flexibility.
According to an aspect of the present invention, there is provided a multimedia data storage medium in which multimedia data is stored. The multimedia data storage medium includes a first layer in which the multimedia data, such as video object images, still images, voice, graphics, and texts, is stored; and a second layer in which, when the multimedia data is divided into the recording unit and the reproduction unit, information regarding attributes of the record unit and relationship between the record unit and the reproduction unit are described with the markup language using elements and the attributes.
The navigation data, which is used to control a selection of the reproduction unit and the reproduction sequence, may be recorded on a third layer using the markup language or the script language, in addition to the information recorded on the first and second layers.
Additional aspects and/or 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.
Brief Description of the Drawings
The above and/or other aspects and advantages of the present invention will become more apparent by describing in detail a preferred embodiment thereof with reference to the attached drawings in which:
FIG. 1 illustrates a conventional multimedia data recording/reproducing apparatus;
FIG. 2 illustrates a data structure of a conventional DVD;
FIG. 3 illustrates a VMG area;
FIG. 4 illustrates a VTS area;
FIG. 5 illustrates a reproduction unit one_sequential_PGC_title,
including only a single PGC;
FIG. 6 illustrates the reproduction unit in which a title is linked to a plurality of PGCs;
FIG. 7 illustrates a structure of the PGC;
FIG. 8 illustrates a case of branching a new PGC using command navigation information during or after reproduction of the PGC;
FIG. 9 illustrates a data structure of a TT_SRPT information table;
FIG. 10 illustrates a data structure of VTS_PTT_SRPT information inaVTSI;
FIG. 11 illustrates contents of a PTT_SRP, designating the PGC and a program in the PGC;
FIG. 12 illustrates a data structure of a PGCIT VTS_PGCIT, representing a PGCI table in the VTSI;
FIG. 13 illustrates a detailed data structure of a VTS_PGCI;
FIG. 14 illustrates a filel .mpg and a file2.mpg, in accordance with an aspect of the present invention;
FIG. 15 illustrates two video object clips, in accordance with an aspect of the present invention;
FIG. 16 illustrates a position of video object data at a time gap position recorded in a table format, in accordance with an aspect of the present invention;
FIG. 17 illustrates a video object file, in accordance with an aspect of the present invention;
FIG. 18 illustrates the reproducing apparatus, in accordance with an aspect of the present invention; and
FIG. 19 illustrates a method of forming a menu screen for navigation, in accordance with an aspect of the present invention.
Best mode for carrying out the Invention
Reference will now be made in detail to the present aspects of the present invention, examples of which are illustrated in the accompanying
drawings, wherein like reference numerals refer to the like elements throughout. The aspects are described below in order to explain the present invention by referring to the figures.
According to an aspect of the present invention, a storage medium on which a video object title is recorded, being supported by a plurality of voice types and subtitles. Additional information may be hierarchically recorded and a markup language is used to implement each layer for extensibility. The markup language, which describes record units and reproduction units, is called a media description language.
Referring to FIG. 14, file1 .mpg, which is a first half of data representing a video object title, and file2.mpg, which is the other half, are recorded in a first layer. A title may be divided into a plurality of files given a size limit of a chapter unit or a file. Video object data is compressively encoded to reduce a data amount thereof. MPEG, which is one of the most popular motion picture compression methods, supports a variable bit rate (VBR) encoding method in which a bit rate per hour varies according to an amount of video information. A time search determining a starting point of the data reproduction with consideration to a given time requires table-type information to map the time and a position of the data. The information is used to detect the position of desired data since a predetermined time after a start of the data reproduction. In general, the table-type information includes information regarding data positions measured at every predetermined point of time. For instance, the table-type information may be time map information that represents temporal position linking information indicating the data positions measured with respect to the file beginning every 10 seconds. However, because the amount of time map information is significant, the information is recorded in a binary table format, rather than using the markup language, and stored in the first layer. FIG. 14 Illustrates the time map Information file1timemap.dat and
file2timemap.dat, regarding the video object data filel .mpg and file2.mpg, respectively. According to an aspect of the present invention, actual time map information is illustrated in FIG. 16.
Additional data, regarding multimedia data recorded on the first layer, is recorded on a second layer. The additional data defines a reproduction unit to appropriately reproduce the multimedia data on the first layer. Here, the reproduction unit may be divided into record units or units of storage, which are described in a binary table format, or in an alternative aspect of the present invention, using the markup language, and stored as a description.xml file. Navigation information, which is to be added to the additional data, is recorded on a third layer as a menu.xml file. The stored navigation information determines a selection and sequences of the data reproduction by controlling the reproduction unit recorded on the second layer.
In general, a menu screen is organized in a recording medium, on which a plurality of titles or chapters are recorded, to allow random access of a particular title or chapter in a user selection and immediate reproduction at a specified position. In the menu screen, still images and buttons are generally formed. Also, background music may be reproduced. When a user selects a button, a function associated with the button is executed. Referring to FIG. 14, the still images and music data included in the menu screen are recorded as file3.jpg and file4.mp3 files on the first layer.
The additional data recorded on the second layer describes the information regarding the data recorded on the first layer. Video object data is multiplexed in a data stream to synchronize video, audio, and graphic data. The attributes of the record units of the video object data are described as description.xml, using the attributes of the video, audio, and graphic data, and numbers of audio, video, and graphic data. Further, the additional data provides information regarding reproduction
units that are generated by a combination or a selection of the record units.
In an aspect of the present invention, a 'clip' is used as the record unit and 'cells', 'chapters', and 'titles' are used as the reproduction units. The following description provides explanations on these units (see FIG. 15): clip: The clip is an object described in relation to the recording of the multimedia data. FIG. 15 illustrates two video object clips. The video object clip has information about the time and the position. The data belonging to the clip can be continuously reproduced. That Is, an mpg file including the video object data and a time map file including the temporal position information are combined to form the clip. The time map file includes the addifional information that enables a quick search for a desired temporal position of the video object data when the video object is VBR encoded.
That is, if the video object file is the VBR encoded as shown in FIG. 17, the position of the video object data at a time gap position, designated by predetermined time intervals from a starting position, is recorded in the table format shown in FIG. 16. If the data position in the table is called an entry, a total number of entries and time gaps may be recorded at a beginning of the table. A search of a desired position of the data, with respect to a predetermined instant of fime, can be accomplished by detecting the time gap position most proximate to a predetermined instant of time recorded in the table. The desired data may be precisely reproduced by reading the data starting from the detected position. If the data is recorded at a constant bit rate (CBR), it is possible to maintain the coded data amount generated for a predetermined fime. In this case, the clip can be constructed with only video object data because it is possible to detect the desired position of the data using the time calculations according to the CBR without the fime map information.
The following information is used to define the video object clip including the video data, a plurality of audio data groups, and a plurality of graphic data groups:
(a) general attributes: clip identification information, video object clip files, and clip temporal position information file (time map file);
(b) video: screen size (e.g., 1920'1080,1280720, and 720'480), average bit rate (e.g., 4M, 6M, 10M, and 20M), screen output rate (e.g., 60Hz, 30Hz, and 24Hz), scanning types (e.g., progressive and Interlaced types);
(c) audio: audio stream identification information, audio encoding information, linguistic attributes of each audio data group (e.g., Korean, and English), and application attributes of each audio data group (e.g., main audio, sub audio, and commentary); and
(d) graphic: graphic stream identification information, graphic encoding information, linguistic attributes of each graphic data group (e.g., Korean, and English), application attributes of each graphic data group (e.g., subtitles, and animation)
The above information, however, may be changed according to the recording type, encoding type, and multiplexing type of the multimedia data. Also, the record unit may form a hierarchical structure, and, thus, the record unit subordinate to the clip may be present. For convenience, according to an aspect of the present invention, the record unit is determined to be made of clips.
In general, the reproduction unit has the hierarchical structure, that is, the reproduction unit includes a plurality of reproduction sub-units. In this case, the reproduction sub-unit is defined as a unit of a reproduction sequence or a point of random access.
Referring to FIG. 15, a cell is the reproduction unit that is described in relation to the reproduction of the multimedia data, each cell designating the clip or a portion of the clip. The cell represents a lowest
layer of the reproduction unit. That is, the cell, i.e., a reproduction unit, is linked to at least one clip, i.e., the record unit, in the reproduction of the multimedia data.
The cell is defined using the identification information, and the starting and ending times of the related clip. However, if the cell designates an entire clip, not a portion thereof, the starting and ending times are not additionally specified.
Referring to FIG. 15, a chapter is the reproduction unit described in relation to the reproduction of the data, each chapter including at least one cell. In general, the chapter is defined by a chapter name, chapter identification information, and information regarding at least one cell belonging to the chapter.
According to an aspect of the present invention, the chapter can be understood as a reproduction point that allows the user to perform the random access. Thus, within the title, the user can search for or reproduce the desired data in units of chapters. In general, the menu screen provides a menu in which the desired data can be selected in the units of chapters.
Referring to FIG. 15, a title includes a plurality of chapters. A plurality of titles may be stored in a storage medium and can be sequentially reproduced according to a sequence of title identification signs. In general, the menu screen provides a menu that allows selection of the title, the title defined by a title name, a title identification sign, and information regarding at least one chapter belonging to the title.
FIG. 15 illustrates a relationship between video object data recorded on the first layer, and clips, chapters, and titles recorded on the second layer.
According to an aspect of the present invention, the information regarding the second layer is described in two types of units, i.e., the record units and the reproduction units, while the data regarding the navigation is eliminated. In general, the data is described in a binary table format or through the markup language. In an aspect of the present invention, the data is described using the markup language because the markup language is more advantageous than the binary table. Extensible markup language (XML), a representative example of the markup language, is defined in W3C, which prescribes recommendations for the Internet. With XML, it is possible to describe a variety of databases and documents. When information regarding the second layer is described with XML, it is very easy to ensure extendibility and backward compatibility.
Hereinafter, the XML-based language will be defined describing the additional information to be stored in the second layer, according to an aspect of the present invention. The XML-based language is referred to as media description language (MDL). XML is described with a combination of hierarchical elements. Also, each element may have several attributes. The name of the element is described within a sign ''. The regulations to describe a sub element are mentioned below.
The MDL, according to an aspect of the present invention, has elements and attributes as described below. Here, a document is understood as a unit of data that is described and stored utilizing the markup language.
(a) The uppermost element of the MDL document is described using
(b) The element
(c) An element contains all information regarding a storage unit
and may have the following sub-element:
(d) An element defines a blank element in which features of a document are defined and appropriate values are allocated to the features. Each element denotes a pair including an attribute and a value.
The attributes of elements defined in the element are as follows:
- Name: A name denotes a document feature defined in the element . The name is an attribute indispensable to the element .
- Content: A content denotes a feature value defined in the element . The content is also an attribute indispensable to the element .
The following are examples of the element excluding conventional examples of the element : e.g., (i) , which describes a disc that is manufactured using the media description language; and (ii) , which indicates that the regional code of the disc is 1.
(e) The element may have the following sub-elements:
(f) The element
- Id: representing the identification information for each clip. Id varies according to the type of storage medium (e.g., 1, 2, or 3),
- src: representing a video object data file such as 'file1 .mpg', and
- tmap_src: representing a file containing a time map table (e.g., file1timemap.dat)
|Indian Patent Application Number||190/DELNP/2005|
|PG Journal Number||09/2011|
|Date of Filing||18-Jan-2005|
|Name of Patentee||SAMSUNG ELECTRONICS CO., LTD.|
|Applicant Address||416, MAETAN-DONG, YEONGTONG-GU, SUWON-SI, GYEONGGI-DO, 442-742, REPUBLIC OF KOREA|
|PCT International Classification Number||G06F 3/06|
|PCT International Application Number||PCT/KR2003/001877|
|PCT International Filing date||2003-09-09|