MXPA01002074A - Order of titles in a real-time dvd video recording - Google Patents

Abstract

A method of recording an encoded bit stream, said encoded bit stream representing a plurality of video objects comprising a sequence of cells together constituting a part of an MPEG2 Program Stream, on a disc like record carrier, such as an optical disc. The method comprises recording a collection of contiguously arranged video objects and management information about recorded video objects. The collection is partitioned into adjacent recordings that represent playable titles, wherein a playable title is defined as a playback sequence of all complete cells or a subset of complete cells of a recording in the order of allocation within the video object storage area on the disc. The method further comprises generating a title list of titles sorted in the order of arrangement within the video object area on the disc. The method defines a free space title that represents free space within the video object area and includes the free space title in the title list.

Description

ORDER OF TITLES IN A REAL TIME VIDEO DVD RECORDING FIELD OF THE INVENTION The invention relates to a method for recording encoded information signals as recited in the preamble of claim 1 in a disc-like engraving carrier, such as an optically readable disk. The invention also relates to an engraving apparatus for carrying out the method.

BACKGROUND OF THE INVENTION The DVD Video format for optically readable discs is defined in the DVD Specifications for Read Only Discs, part 3: Video Specification (version 1.0 August 1996). Relevant parts of there are described by, example in the European Patent Application EP 724 264 and the US Patent 5 784 528, respective document D1 and D2 in the list of referred documents that can be found at the end of this description. Both documents are incorporated herein by reference. The DVD Video format as defined in the above-mentioned specifications for READ-only discs and described in D1 and D2 was created to store movies and other video content on read-only DVD media. Some features of the DVD Video format make it less suitable for real-time recording applications. However, it is desirable to create and record video streams and associated data structures in real-time rewritable media which should preferably be almost identical to the structures defined in the DVD Video format. Such rewritable discs must be play-back compatible with most of the installed base of consumer DVD Video devices. The method according to the invention describes a novel and inventive format for DVD Video compatible with real-time recordings of video streams, referred to hereinafter as Real Time DVD Video Recording or short DVD Video Recording. The defined format is intended for a home video recording in an optical medium that is play-back compatible with DVD Video devices. The DVD Video format mentioned above requests that the data for a VTS be assigned contiguously. This gives all kinds of problems when part of the data is overwritten with new recordings: The DVD Video format allows an arbitrary number of Video Titles (VT) within a Set of Video Titles (VTS). For example as the sequence of the Video Titles: VT1, VT2, VT2, Overwriting for example a Video Title VT 3 with a new Longest Video Title VT4, will result in overwriting also the Video Title VT2. This may seem strange for a user, to use a menu of Video Titles that list the Video Titles in consecutive order: VT1m VT2, VT3 This sequence would be changed in a sequence such as: VT1, X, VT4, with X denotes an erased Video Title. Therefore, when partial overwriting is one of the characteristics, the user model of the recording medium becomes complicated.

OBJECTIVE AND SUMMARY OF THE INVENTION Accordingly, among other things, it is an object of the invention to obviate the aforementioned disadvantages. According to one of its aspects, a recording method for the invention is characterized as recited in the feature part of claim 1.

When defining the objects to be played and the list of playable titles in the order of assignment, the recording medium appears to a user as a sequential cassette type medium. The user will understand that when a specific recording is overwritten, a subsequent recording can also be overwritten. You will not understand this if the recordings were randomly ordered, as allowed in the DVD Video format, which may lead to the disappearance of a previous recording when a specific recording is overwritten. This allows a play-back device to employ a simple user model in the case of real-time DVD video recordings. A menu of titles, used by an apparatus to display and select, can be read simply from the administration area. There is no need to read the information in the video storage area itself and therefore calculate a menu of titles. This means that an apparatus adapted for play-back of prerecorded DVDs of Only Reading, does not require modification to display a menu of suitable titles. Other advantageous aspects of the invention are recited in other dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS These and other aspects and later advantages of the invention will be apparent and elucidated in more detail hereinafter with reference to the description of preferred characterizations, in particular with reference to the accompanying figures in which, Fig. 1 illustrates the logical data structure of a DVD disc corresponding to a characterization for DVD Video Recordings according to the invention; Fig. 2 illustrates in more detail the structure of the Video Manager area (VMG) of Fig. 1; Fig. 3 illustrates in more detail the structure of the Video Title Determination Information (VTSI) area of Fig. 1; Fig. 4 illustrates the structure of the Video Manager Information Management Table (VTSI_MAT) of Fig. 2; Fig. 5 illustrates the structure of the Program Chain Information (PGCl) area; Fig. 6 shows an example of finding a Title Program Chain Information (PGCl); Fig. 7 shows a recording apparatus according to a first characterization of the invention, the respective units therein are illustrated in more detail in the following figures of which Fig. 8 shows an A / V input unit; Fig. 9 shows a CODEC unit; Fig. 10 shows an A / V output unit; Fig. 11 shows a pulse unit, and Fig. 12 shows a system control unit.

DESCRIPTION OF THE CHARACTERIZATIONS The data structure to be described in the following explains the DVD Video compatibility behind the Real Time Video Recording Format and specifies how the recorders should use it to create compatible DVD Video play-back discs.

To overcome the limitations for real-time recording of the DVD Video format for read-only discs, a number of changes have been made in the organization of data and the use of some recording parameters in the real-time data stream. The use of Titles and Menus is restricted to the improvement of the exchange of rewritable discs between recorders. In addition to this, strict rules define strict rules for the Playlists, which can be created by the user to define the play-back sequences of pieces of the recorded Titles. First, a list of definitions is provided. Access unit Coded representation of a presentation unit. See ISO TEC 13818 related to MPEG-2 systems, document D3 in the list of referred documents that can be found at the end of this description. For a more detailed definition of MPEG audio and video access units.

Horn Cell The last Cell of a Video Object (VOB) that contains only a Video Object Unit (VOBU). The Horn Cell is not used by any Program Chain (PCGC). The Cell ID of a Speaker Cell is equal to 255.

Cell Sequence of one or more Video Object Units (VOBU). The first VOBU of a Cell will contain video data. The Cells are basic presentation units for the Program Chains (PGC) Chapter Subdivision of a Title. Another word for Part_del_Título (PTT).

DVD-VR Format Short Term for Video Format Specifications for Recording Real Time DVD Video.

DVD Video format for read-only discs The format as specified in the DVD specifications for Read Only Disc - Part 3: Video Specifications (version 1.0, August 1996), elements which are described in D1 and D2.

DVD Video format for recordable discs Format of DVD Video related structures with the modifications specified in this description.

Elemental current An elementary stream is a generic term for a sequence of encoded video, encoded audio, encoded graphics or other access units that can be decoded correctly by a hypothetical decoder that operates without special control of an external controller.

Free space Record that is represented by a Title of Free Space in the Table of Apunte of Search of Titles. If the last Recording is a free space, it is not represented in this table.

Title of Free Space Full Title or Title of Playlist that can not be done play-back, since the Program Chain Information contains a pre-command to prevent this. The Play_Time (), Search_Time (), PTT_Reproduction () and PTT_Search () for a Free Space Title are blocked. The Cell information in the Program Chain of a Free Space Title may not be reliable.

Full Title Title that represents a Recording. When a Full Title is played, all complete Cells (with the exception of the Speaker Cells) contained in the Recording are reproduced in the order of the data assignment in the VOBS VTS Title. Full Titles can be accessed via the Titles Menu.

Group of Images (GOP) Series of coded images that start with a GOP header followed by an intra-coded image. The GOP represents up to 36 fields of deployment at an average of 59.94 Hz, or 30 fields at an average of 50 Hz.

MPEG-2 Program Stream (MPEG-2 PS) Program Stream as defined in ISO TEC 13818-1 related to MPEG-2 systems, document D3 in the list of referred documents that can be found at the end of this description.

Multiplexed current A multiplexed current is a single bit stream, which combines one or more elementary streams that can be reproduced in synchronization.

Playlist (or Playlist Title) Title that represents a play-back sequence of Cells of a Recording.

Playlists are accessible via the Title Menu.

Program Chain (PGC) Cell play-back sequence for the presentation of a Menu or a Title.

Royal Title Full Title or Title of Playlist that is not a Title of Free Space.

Recording Adjacent part of the VOBS VTS Titles, including a whole number of MPEG-2 PS packages. The VTS of VTS Titles is divided into adjacent Recordings that do not necessarily coincide with the VOBs in the VOBS.

Title Unit accessible to the user listed in the Table of Apuntado de Búsqueda de Titles.

Titles Menu This is a menu that provides the user with access to the Playlists and optionally to Full Titles.

Targeted Search Table for Titles Table in the Video Manager that lists all the available Playlists and Full Titles on the disc. It is a starting point to find data that are relevant to the play-back of a Title.

Video Manager (VMG) The DVD Video data structures contain information about the recorded video data and the Title Menu. The Targeting Search Table is one of the elements of the Video Manager.

Video Object (VOB) A Video Object is (a part of) a sequence of contiguously recorded Cells, which together constitute (a part of) an MPEG-2 Program Stream.

A whole number of MPEG-2 Program Component packets can be omitted from the beginning of the first VOB Cell, if this Cell is not used by any Title. The last Cell of a VOB is a Horn Cell.

A VOB will contain an elementary stream of video. Spaces in the video stream are allowed under conditions specified by the DVD Video specifications.

According to DVD Video specifications, a VOB can also contain up to eight audio streams (in elementary audio streams and / or in private streams) and up to 32 sub-picture streams. The DVD VR format only allows one Audio stream and one sub-picture stream within the same VOB.

Video Object Unit (VOBU) The integer number of MPEG-2 Program current packages represents a presentation period between 0.4 and 1.0 seconds.

The last VOBU of a Cell has a maximum presentation period of 1.2 seconds. When the VOBU contains Video, the video data consists of a whole number of GOPs and begins with a sequence header, a GOP header and an intra-coded image.

A Sub-Image Unit is optional in a VOBU and can not cross the boundaries of the VOBU. The associated validity period SPU ends on or before the final presentation time of the VOBU.

Video Object Set (VOBS) This is a collection of contiguously recorded VOBs.

The VOBs that are used for menus are stored in the Administrator VOBS video (VMGM_VOBS). The VOBs that are used for the Titles are stored in the VOBS of VTS Titles (VTSTT VOBS).

Fig. 1 shows the general data structure according to the Real Time Video Recording format. The data structure comprises a Lead-In / Input Guide (Ll) area, a Volume (VOL) and a File System (FS) area, a Video Manager area (VMG), a Video Title Set (VTS), an area reserved for other structures (OTHERS) and a Lead-Out / Output Guide (LO) area as it is known from the DVD-ROM data structure. Not shown specifically in Fig. 1 is the Presentation Control Information (PCI) and the Data Search Information (DSl) within the Video Object Set for VTS Titles (VTSTT_VOBS), both scattered in the packets of Navigation (NV_PCK) of each Video Object Unit (VOBU). The organization of data according to the Real Time Video Recording format will first be discussed in general. With respect to the Video Manager (VMG) the following is observed. The Video Manager (VMG) will contain a Title Menu. Therefore, a Video Object Set for the Video Manager Menu (VMGM_VOBS) is essential. With respect to the Video Titles Sets (VTS) the following is observed. The data structure on a disk contains only one Set of Video Titles (VTS). The Root Menu It will contain a Test Program Chain (PGC) with a pre-command that calls the Titles Menu. No other Video Titles Set (VTS) will be present on the disc. Therefore the Video Titles Set (VTS) does not contain a Video Object Set for a Video Titles Set Menu (VTSM_VOBS). The Video Object Set for the Video Title Set Titles (CTSTT_VOBS) of the Video Title Set (VTS) contains the recorded video content. With respect to the Video Object Set (VOBS), the Video Object (VOBs) and the Cells, the following is observed. A Video Object (VOB) is (a part of) a sequence of contiguously recorded Cells, which together constitute (a part of) an MPEG-2 Program Stream as defined in D4. An integer number of MPEG-2 Program Stream packets can be omitted from the beginning of the first Video Object Cell (VOB) if this Cell is not used by any Title. The last Cell of a Video Object (VOB) is a Speaker Cell, which is not used by any Title. A Video Object Set (VOBS) is a collection of Video Objects (VOBs) recorded contiguously. Video Objects (VOBs) and Cells on a rewritable disc are not fully compatible with the Video Specifications for the DVD Read Only Disc as described in D2 and D4. The following exceptions are allowed or required: 1) The DVD Video specification requires that a Video Object (VOB) start with a System Clock Reference (SCR) equal to zero. This is not required for DVD VR discs. 2) The Deployment of the video stream of a Video Object (VOB) does not have to start with a higher field or end with a lower field. 3) The DVD Video specification prescribes an increase in the number of Video Objects (VOBs) and Cells. When the disc is recorded for the first time that The requirement can usually be met. Nevertheless, when old recordings are overwritten (in part), or when the user is editing, it may not be possible to keep increasing the number. To overcome this problem, the DVD-VR format requires that the Video Object Identification Number (VOB ID) of all Video Objects (VOBs) be equal to. In addition to this, the ID Cell numbers (except number 255) remain as unique even though they are allowed to be non-sequential. 4) Video Objects (VOBs) and Cells contain Navigation Packs (NV_PCK) with shipping references for ease of expedition search. Some of these shipping references can not be known at recording time and therefore must be encoded with the values that make legacy play-back devices behave in an acceptable manner.

) Navigation Packs (NV_PCK) also contain a parameter that specifies the presentation completion time of the last video structure of the Video Object (VOB). This parameter can not be done correctly in real time in all cases. To solve this problem a high number will be recorded for this parameter. A Horn Cell at the end of a Video Object (VOB) guarantees that at the end of a Video Object (VOB) it will never be reached during the play-back.

Regarding the recordings, the following is observed: The Video Object Set for Titles in a Set of Video Titles (VTSTT_VOBS) can be divided into a collection of adjacent pieces, called Recordings, that do not necessarily coincide with the Objects of Video (VOBs). Recordings include a whole number of MPEG-2 PS packages.

Recordings are related to the division of content as presented to the user. With respect to the Complete Titles, the Playlists and Free Space, the following is observed; For each Recording two Sequences_of_Un_PGC_Secuenciales are created: a Title Complete and a Playlist. The Full Title defines the play-back of all the complete Cells (except the Horn Cells) of a Recording in the order of assignment in the Video Object Set (VOBS). The Playlist may be different from the Full Title. If so, it defines the play-back of a subset of the Cells that the Full Title is playing. Each Full Title and Playlist is represented as a Title in the Targeting Table of Search in VMGI Titles (TT_SRPT) and as a Title Unit (TTU) in the Part of the VTSI Title Search Table (VTS_PTT_SRPT) . A Playlist points to the same Program Chain (PGC) as the corresponding Full Title, unless a different Program Chain (PGC) is recorded for the Playlist. The Full Titles and the Playlist Titles are Real Titles, unless they are labeled as Free Space. When the user deletes a Full Title, the Complete Title and Play List in the Title Search Point Table (TT__SRTP) are labeled as Free Space ai to set a Play-back Type value (TT_PB_Y). If two consecutive Full Titles are deleted, the entries in the Title Search Notes Table (TT_SRTP) will be combined in a new Title. Also the Playlists are combined and labeled as Free Space. The free space that is available on the disk at the end of the Title VOBS VTS or beyond the limits of the VTS, is not reflected in the TT_SRPT. Fig. 6 illustrates an example of a PGCI of Titles. Within Fig. 6 the following data structures are provided: Type of Title Play-Back (TT_PB-TY), Part_of_Title Number (PTT_Ns), VTS Title Number (VTS TTN), Number_PGC (PGCN), Number of Program (PCN), Start Address of Table of Information of Chain of Program VTs (VTS: PGCI-SA), Table of Information of Chain of Program (PGCIT), Number of Angles (AGL_Ns), field_ID_Matríz for Title (TT_PTLJD-FLD ), VTS Number (VTSN) and Matrix ID field (PTL_ID: FLD). Each Title (except for the last Playlist Title and the last one Full Title) is linked to the next Title by a LinkPGCN instruction in the Associated Program Chain Information (PGCI). The Program Chain Information (PGCl) of the last Playlist and the last Full Title contains a CalISS for the Titles Menu. If the Title is labeled as Free Space, this instruction is stored as a pre-command in the Program Chain Information (PGCL). Otherwise the instruction is stored as a post-command. The number of Full Titles on a DVD VR is equal to the number of Playlists with a maximum of 49. The Titles can be subdivided into a maximum of 99 Chapters (Part_of_Titles). The maximum number of Chapters for all Full Titles on a disk is 254. Restrictions and modifications compared to the read-only format will be provided below. As already described with reference to Fig. 1, exactly one Video Title Set is recorded on disk. Fig. 2 illustrates the data structure of the General Video Manager Information (VMGI) within the Video Manager area (VMG) As shown in Fig. 1. As in Fig. 1, the Presentation Control Information (PCI) and the Data Search Information (DSI) are not shown in Fig. 2, although this information is scattered in the corresponding Navigation Packs (NV_PCK) in each Video Object Unit (VOBU) of the Set of 5 Video Object for the Video Manager Menu (VMGM_VOBS). With respect to the Video Administrator Information Management Table (VMGI_MAT), the first 8 bytes of the Unique Provider ID (PVRJD) contain ef Loop 'DVD-VR01'. The First Play Program Chain (FP_PGC) contains only one JumpSS for the Title Menu as a pre-command. 10 The Title Search Chart (TT 5RPT) consists of two sections of equal length. The first half contains pointers for Playlists N and the second half contains pointers for Full Titles N. The Playlists as well as the Full Titles are selected in order to increase the start addresses of the first Cell used in the Set of Object of Video (VOBS). All titles are Sequences_of_Un_PGC_Sequential for which Play_Time () and Search_Time () are blocked. Part_of_Title_Play () and Part_of_Title_Search () will be blocked for Titles that are associated with Free Space and will not be blocked for other Titles. Table 1 lists Allowed Playback types as indicated in the field of Ttpo_Playbad < ptulo (p_PB_TY).

Table 1 Allowed values of TT PB TY Value of TT PB: TY Type of Title 0000 0101b Real Title that is not the last Playlist or the last Complete Title 0001 0101b Real Title that is the last Playlist or the last Full Title 0000 0111b Free Space Title The Video Manager Menu Program Unit Information Table (VMGM_PGCI_UT) is only linked to the Title Menu. There should only be one Language Unit. The Video Manager Menu exists in the Language Unit. After the Video Title Set Attributes Table (VTS_ATRT), the Video Manager Menu Cell Address Table (VMGM_C_ADT) is restricted to a maximum of 170 cells in the Video Object Unit Address Map from Video Manager Menu (VMGM_VOBU_ADMAP) to a maximum of 511 VOBUs. The remaining part of the Video Manager (VMG) area is occupied with the Video Manager Menu Video Object Set (VMGM_VOBS) and the Video Manager Information Reinforcement (VMGI_BUP).

With reference to Fig. 3, Title Set Information (VTSI) will be discussed. Since the Root Menu contains only one Test Program Chain (PGC) and no other means are allowed, the Video Title Set (VTS) Menus do not have associated Video Object (VOB) data. Consequently, there is no Table of Cell Addresses of the Video Titles Sßt Menu (VTSM_C_ADT) and the Map of the Video Object Unit of the Video Titles Set (VTSM_VOBU_ADMAP). The Video Title Set Information Management Table (VTSI_MAT) comprises the following area (not shown in the figure): - VTS Video Attributes (VTS_V_ATR) (the video compression mode is compatible with MPEG-2), - the number of Audio Currents (VTS_AST_Ns) that describe the number of different sets of audio stream attributes used in this VTS, the Audio Stream Attributes Table (VTS_AST_ATRT) that lists the different sets of audio stream attributes that are defined (and may or may not be used) for this VTS. The PGCl for each Title defines which of the sets is actually being used, the number of Sub-Image Streams (VTS_SPST_Ns) (set to one in this VTS) and the VTS Sub-image Component Attributes Table ( VTS_SPST_ATR) (all fields in this table are zero) The Video Title Set Information (VTSI) also comprises a Table of Search Pointer for Part_of_Title of Video Titles Set (VTS_PTT_SRPT) where the Title Units are recorded in the same order as the Titles in the Title Search Pointer (TT SRPT). Below is a Table of Information for the Program Chain of Video Titles Set (VTS_PGCIT). The number of search pointers of the Video Title Set Program Chain (VTS_PFCI) is equal to the number of Titles in the Title Search Pointer Table (TT_SRPT). The search pointers are recorded in the same order as the Titles. All Program Chains (PGCs) are Input PGCs with all bits zero for Block mode, Block type and Matrix ID field (PTLJD_FLD). When a Playlist is equal to the associated Full Title, its Start Address of the Video String Set Program Information values are identical. With respect to the Table of Information Unit of Program Chain of Set-of Video Titles (VTSM_PGCt_UT) the following is observed. The number of Menu Language Units of Set of Video Titles as shown Specified in VTSM_PGCI_UTI will be 1. There is exactly one Search Title Unit of the Video Title Set Menu Language (VTSM_LU_SRP). The Video Title Set Menu Existence field (VTSM_EXST) will contain the value (1000 0000b) to indicate that only the Root Menu exists. The Video Language Set Menu Language Unit (VTSM_LU) contains only a Program Chain Information Search Pointer (VTSM_PGCI_SRP). The Program Category Category parameter of the Video Titles Set Menu (VTSM_PGC_CAT) for the Video Titles Set Menu Program Chain (VTSM_PGC) contains the value (8300 OOOOh) that indicates that the associated Program Chain (PGC) is the Input PGC for the Root Menu. There is exactly one Program Chain Information of Video Titles Set Menu (VTSM_PGCI). . The Video Title Set Time Map Table (VTS_TMAPT) contains Video Title Set Time Maps (VTS_TMAPs) that are present for all Titles on the disc but do not contain any map entries. With respect to the Table of Addresses of Video Title Set Cells (VTS_C_ADT), the parameter containing the number of Video Objects in the Video Title Set (VTS_VOB_Ns) contains the value 'I'. Note that VTS_VOB_Ns do not reflect the actual number of VOBs in the Video Object Set of a rewritable disc. It is set to 1 since the VOB ID number of all VOBs are set to '1'. All the Cell Part Information, Video Title Set (VTS_CPI) have the same vafor ('1') for the Video Title Set Video Object ID Number (VTS_VOBJDN). Exactly 254 VTS_CPI blocks are recorded with VTS_C_IDN starting from '1' and increasing to '254'. The Start Address and the End Address of the Video Title Set Cell Piece (VTS_CP_SA and VTS_CP_EA) of the Cell Pieces that are not referred by any PGC of a Real Title contains the value (0000 OOOOh). It is noted that the Cell Pieces that are referred by a PGC of a Free Space Title contain start and zero end addresses. With respect to the Video Object Unit Address Map of Video Titles Set (VTS_VOBU_ADMAP) it is noted that all of the Video Object Unit start addresses (VOBU) of the VOBUs that are fully contained in the VTSTT_VOBS are listed here in ascending order. It is noted that the VOBU start addresses of the VOBUs that are part of the Free Space are also included in the VOBU VOBU map of VTS. Next, the structure of the Program Chain information area (PGCI) for Title Program Chains will be provided with reference to Fig. 5. This structure comprises a General Program Chain Information Area (PGC-GI), a Program Chain Command Table (PGC_CMDT), a Cell Play-back Information Table (C__PBiT) and a Cell Position Information Table (C_POSIT). With respect to the General Program Chain Information (PGC-GI) it is noted that exactly one of the Availability flags in the Program Chain Audio Stream Control Table (PGC_AST_CTLT) is set to (1b). When the i * Availability flag is set, the audio current parameter set i * defined for this Video Title Set (VTS) is valid for this Program Chain (PGC). The Decoding Audio stream number is always O '. The availability flag of the Program Chain Su- pface Control field (PGC_SPST_CTL) in the Su-Image Program Correction Control Table (PGC_SPST_CTLT) is set to (1b). All other bits of the Program Sub-Image Comment Control Table (PGC_SPST_CTLT) contain the value (Ob). The Program Play-back mode (PG) in the Program Chain Navigation Control (PGC_NV_CTL) is set for sequential play-back. The Timeout value is set to Not Wait. The PGC Command Table (PGC_CMDT) contains exactly three commands. According to this version of the specification only one command is actually used (to link Titles), the other two commands are NOP commands (0000 OOOOh). The command that is used to link Titles is defined in Table 2.

Table 2 Commands in PGCl With respect to the Cell Play-back Information Table (C_PBIT): Cells are not part of an Angle Block and do not exist in an Interleaved Block. With respect to the Cell Position Information Table (C_POSIT): the Identification Numbers of the Video Objects of all the Cells in the PGC contain the value '1'. It is noted that on DVD-VR, all VOBs have the same VOBJDN. The Cell ID number of a Cell from which the Perfect playback flag set in the Cell Play-back Information is allowed, is not the same as the previous Cela ID number incremented by 1. With respect to to the Presentation Control Information (PCI) it is noted that modifying a Playlist may require that a Cell be divided into two new Cells. In this case, all Cell Transcum Time values (C_ELTM in PCI_GI) will be updated in all the PCI fields in the second Cell. Additional data fields regarding the DVD Video format for Read Only discs to carry out the real time stream attributes are provided below. The last 32 reserved bytes of the General Information of Presentation Control Information (PCI_GI) are redefined in this specification as shown in Table 3.

Table 3 Redefinition of reserved fields at the end of PCI_GI The PCI_GI_XI identifies the application and specifies the length of the extension. If all the bits in this byte are zero, then the PCI_GI bytes following this field will be zero: b7 b6 b5 b4 b3 b2 b1 bO Application Identifier Extension Length The Application Identifier contains the value (0001b) if the current attributes as defined in the VTSI_MAT for this VTS must be invalidated by real-time stream attributes. Otherwise it contains the value (OOOOb). The real-time stream attributes are valid from the Start PTM to the Term PTM of the VOBU in which this field is contained.

The Extension Length defines the number of bytes for this extension following this field. It will contain the value (0010b) if the Application identifier is (0001b). It contains the value (OOOOb) if the Application Identifier is (OOOOb). The RT_V_ATR describes the attributes of real-time Video stream. b7 b6 b5 b4 b3 b2 b1 bO The aspect ratio, picture source in letterbox and camera mode have meanings as defined in the specifications for the Read Only Disc. The RS_AST_ATR describes the real-time Audio stream attributes: b7 b6 b5 b4 b3 b2 b1 bO reserved | Type around | reserved Type around as defined in the DVD Specifications of the Read Only Disc. With respect to the Data Search Information (DSI) it is noted that all VOBs are assigned in Contiguous Blocks and there are no Angles. With respect to the General Information Information of Data Search (DSI 3I) it is observed that the ID number of the Video Object (VOB ID) is always 1. In addition there is no requirement that the cell ID numbers increase in form monotone of 1 in the Video Object. The following rules will apply for the Cell ID: the Cell ID is identical in all the VOBUs belonging to the same Cell. The Cells that are used by the Real Titles are uniquely identified by their Cell ID.

It is noted that modifying a Playlist may require that a Cell be divided into two new Cells. In this case, all the values of the elapsed time of the cell (C-ELTM in DSI_GI) will be updated in all the DSI fields in the second cell. With respect to the Video Object, it is noted that a whole number of the MPEG-2 Program Component packets may be missing from the beginning of the first VOB Cell, if this Cell is not used by any Title. The last Cell of a VOB is a Horn Cell. It is noted that the perfect connections between the VOBs are excluded. Only one Audio stream is allowed inside a VOB. The audio decoder comment number is '0'. The data for the Sub-Image Unit (SPU) are fully contained in a VOBU. The validity period of the SPU will not begin before the VOBU Start PTM, nor will it end after the VOBU Term PTM. The DVD Video format for rewritable discs is not completely identical to the DVD Video format for read-only discs. The differences are (1) in the rules for data assignment and (2) in some details of the navigation data in the real-time data streams. The first type of difference usually has no consequences for DVD Video devices. As a consequence of the second type of difference in some cases the behavior of tricks mode of DVD Video play-back devices with rewritable discs may not always be exactly the same as with pre-recorded discs. Manufacturers can improve compatibility between DVD Video devices and recordable discs by following the guidelines given below. With respect to the VOBS Structures; On rewritable DVD Video discs some rules for the Video Object Set data structures are different of the rules for read-only disks. DVD Video devices will play-back rewritable discs when they are robust against: - non-sequential numbering of VOBs in VTSTT_VOBS - non-sequential numbering of cells within a VOB - the existence of remnants of partially overwritten Cells or other unused data between the "active8" cells - modified rules for send search pointers as described below: DVD Video recorders are required to at least fill in send pointers F DI (n) for n < M. The pointers of FWDI (n) with M < n &nt; N contain the last correct value For the n > N sending pointers pointing to the end of the current cell The duration of a cell on a rewritable disk is typically 60 seconds This means that for functional DVD Video Search devices you can still rely on FWDI pointers for lower speeds (2x, 4x, 8x). For higher speeds, the device can still use the FWDI long-distance pointers but in this case they point to the end of the current cell. If you want fast and accurate search speeds, you can adjust the speed by choosing intermediate images (eg, Ai apply an FWDI pointer (6)) or by adapting the period of display of the images. Fig. 7 shows a recording apparatus according to the first characterization of the invention. The recording apparatus is composed of several units. A unit is unit 1 input A / V. The A / V input unit 1 receives the image and sound signals in an antenna input terminal 2 and an external terminal 3 of image sound input. The antenna input terminal 2 is adapted to receive predicted modulated A / V signals, transmitted either by satellite, a terrestrial or cable source. The external image input terminal 3 is adapted to receive an unmodulated audio signal or unmodulated video signals generated directly by an audio or video source respectively. Fig. 8 illustrates an A / V input unit 1 in more detail. A tuner 5, which is connected to the antenna input terminal 2, demodulates the modulated A / V antenna signals and outputs the demodulated signals to a demultiplexer unit AA / suitable for separating audio signals from video signals. An A / D audio converter unit 7 outputs an A digital audio signal and an NTSC / PAIJSECAM decoder unit 8, comprising a video A / D converter, outputs a digital video V signal. These signals A and V are sent to a coding / decoding unit 9, which is illustrated in more detail in Fig. 9. The coding / decoding unit 9 compresses and encodes the signals A and V, respectively by an audio encoder 10 and a video encoder 11, converts them into a compressed and multiplexed stream that conform to Video Recording specifications, employing a multiplexer 12. For these purposes the audio encoder 10 and the video encoder 11 are adapted to perform a source compression of the video. according to a specific standard for compression, such as MPEG-2 for audio and video. The compressed and muttlipfexed stream is subjected via a tracking horn 13, which absorbs the average fluctuations that arise when intermittently recording and reproducing data from a disk, to a pulse unit 14. The coding and decoding unit 9 also expands a compressed reading of a recording medium by means of the pulse and output unit 14 separately to an audio signal A and a video signal V to a A / V output unit 15. For this purpose, the coding / decoding unit 9 comprises an A / V decoder 16 suitable for decoding the compressed audio and video source signals. The A / V output unit 15, which is illustrated in more detail in FIG. 10, comprises an audio D / A converter to output sound signals to a terminal 18 external sound output. The A / V output unit 15 further comprises a video encoder - D / A converter unit 19 for outputting video signals to an external output terminal 20. Fig. 12 illustrates a pulse unit 14 with more detail. This unit 14 receives the compressed current generated by the coding / decoding unit 9, and adds an error correction code by means of a correct error correction processing unit 21 to the current. Next, a channel modulation / demodulation unit 22 converts (to current with an error correcting code) to bits of channels adapted to record on a recording medium 23. In the case of a DVD disc, the modulation scheme EFM + is applied. .

The recording and reading in the chaos of an optical recording medium 23 is carried out by means of a laser comprised in an optical main unit 25. A laser energy control unit 24 controls the laser. The reflected signals of the recording medium 23 are converted by an amplifier and a waveform equalizer circuit 26 into two value signals. The resulting compressed stream is then demodulated by means of the modulation / demodulation unit 22, corrected for errors by the error correction processing unit 21 and output to the encoding / decoding unit 9 via the tracking horn 13.

A servo circuit 27, connected to the amplifier and to the waveform equalizer circuit 26, controls the positioning of the optical main unit 25 relatively to the recording medium 23 and the rotation speed of the recording medium 23 when controlling the drive means of control rotation. 28. A system control unit 29 controls each block and performs file control, information management control and tracking horn control. For this purpose a system control processing unit 30 is provided which is connected to the memory means 31 loaded with a suitable operating system. The operator input means 32 and the operator output means 33 are connected to the memory means 31. the operator input means 32 comprises for example key means and the operator output means comprises deployment means. Although the invention has been described with respect to the preferential characterizations in relation to this, it should be understood that these are not limiting examples. Therefore, various modifications with respect to this may become apparent to those skilled in the art, without departing from the vision of the invention, as defined in the claims. The invention can be implemented by hardware and software, and the various "means" can be represented by the same hardware article. Furthermore, the invention lies in each of the novel features or the combination of features. It is also observed that the word "comprises" does not exclude the presence of other elements or steps other than those listed in a claim. Any reference signal does not limit the vision of the claims.

LIST OF DOCUMENTS REFERRED (D1) European Patent Application EP 724264 (D2) Patent US 5 784 528 (D3) ISO / IEC 13818-1: 1995 Information Technology - Generic Coding of moving pictures and associated audio information: Part 1: Systems (MPEG2-systems)

Claims (10)

CHAPTER CLAIMING Having described the invention, it is considered as a novelty and, therefore, the content is claimed in the following: CLAIMS

1. A method for recording a coded bitstream, said coded bitstream representing a plurality of video objects comprising a sequence of cells that together constitute a part of an MPEG-2 Program Stream, in a disk-like recording carrier, as an optical disk, said method comprises: recording a collection of video objects arranged adjacently in a video object storage area of said disk, recording management information in a management information area of said disk for storing information about recorded video objects, wherein said collection is divided into adjacent recordings representing reproducible titles, characterized by, defining a reproducible title as a play-back sequence of all the complete cells or a subset of complete cells of a recording in order to assign within the storage area of video objects on the disk, and generate a list of selected titles or titles in the order of placement within the video object area on the disk.

2. A method according to claim 1, characterized by defining a free space title that represents free space within the video object area and include the title of free space in the list of titles.

3. A method according to claim 2, characterized by blocking the free spade titles for play-back.

4. A method according to claim 3, characterized by converting a removed title into a free spade title.

5. A method according to claim 4, characterized by generating a menu of titles that lists the titles in the same order as in the table of tKulos to allow the user access to the titles.

6. A recording apparatus for recording a coded bit stream, representing a plurality of video objects comprising a sequence of cells that together constitute a part of an MPEG-2 Program Stream, in a disk-like recording carrier, such as a optical disk, and recording apparatus comprises: recording means for recording a collection of video objects placed contiguously in a video object storage area of said disk and for recording management information in a management information area of said disk. said disc for storing information about recorded video objects, wherein said collection is divided into adjacent engravings representing reproducible titles, characterized in that, the recording apparatus comprises system control means adapted to define a reproducible title as a play-back sequence of all complete cells or a subset of complete cells of a recording in the order of allocation within the storage area of video objects on the disc and to generate a list of titles of selected titles in the order of placement within the video object area on the disc.

7. A recording apparatus according to claim 6, characterized in that the system control means are adapted to define a free spade title that represents free space within the video object area and that includes the title of free sword in the list of titles.

8. A recording apparatus according to claim 7, characterized in that, the system control means are adapted to block free-play titles for play-back.

9. A recording apparatus according to claim 8, characterized in that the system control means is adapted to convert a deleted title into a free spade title.

10. A recording apparatus according to claim 6, characterized in that the system control measures are adapted to generate a menu of titles by listing the titles in the same order as in the table of titles to allow the user to have access to the titles. titles and recording means comprise output means for displaying the menu of tífulos.