3
`Xe.
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`POO2 ~~]
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`RECORDING MEDIUM, PLAYBACK METHOD, AND PLAYBACKDEVICE
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`CROSS-REFERENCE TO RELATED APPLICATION
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`This is a continuation of U.S. Patent Appl. No. 15/699,105, filed Sept. 8, 2017, which is a
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`continuation of U.S. Patent Appl. No. 15/471,032, filed Mar. 28, 2017, which is a contmuation of
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`International Patent Appl. No. PCT/FP2015/005001, filed Oct. 1, 2015, which claims the benefit of US.
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`Provisional Patent Appl. No. 62/065,034, filed Oct. 17, 2014, and priority to Japanese Appi. No. 2015-
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`148672, filed Fuly 28, 2015. The disclosure of cach of the above-mentioned applications, including the
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`specifications, drawimes, and claims, is incorporated herein by reference inits entirety.
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`1. Technical Field
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`BACKGROUND
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`(O00 1
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`The present disclosure relates to a recording medium in whichis recorded an encoded video
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`stream, a playback method ofthe video stream, and a plavback device.
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`2. Description of the Related Art
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`(0002]
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`Technologyrelating to digital versatile discs (DVD) has conventionally been disclosed(c.g..
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`Japanese Unexamined Patent Application Publication No. 9-282848).
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`SUMMARY
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`{0003 ]
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`In one general aspect, the techniques disclosed here feature a recording medium im whichare
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`recorded a video stream of standard-luminance range, and a video stream of high-luminance rangethat is
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`a broader luminance range than the standard-luminance range, which are used selectively in accordance
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`with a playback environment, a subtitle stream ofthe standard-lumimance range, and a subtitle stream of
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`the hish-huminance range, which are used selectively in accordance with the playback environment, and a
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`playlist file storing playback control information of content, the playlist file mcluding a management
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`region where the playback control information relating to a main stream is stored, and an extended region.
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`The management region stores first playback control information specifying that a video stream of the
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`high-huminance range and a subtitle stream of the ngh-himinance range are to be played in combmation.
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`The extended region stores second playback control information specifyimg that a video stream ofthe
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`standard-luminance range and a subtitle stream of the standard-huminance range are to be plaved in
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`combination. According to the above form, further improvement can be realized.
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`[0004]
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`it should be noted that general or specific embodiments may be implemented as a system, a
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`method, an miesrated circuit, a computer program, a storage medium, or any selective combination
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`thereof,
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`[O005] Additional benefits and advantages of the disclosed embodiments will become apparent from the
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`specification and drawings. The benefits and/or
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`advantages may be individually obtained by the various embodiments and
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`features of the specification and drawings, which need not all be provided in order
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`to obtain one or more of such benefits and/or advantages.
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`BRIEF DESCRIPTION OF THE DRAWINGS
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`6006]
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`Fig. 1 is a diagram illustrating an SD-DVD structure;
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`Fig. 2 is a schematic diagram for describing navigation information embedded in
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`an MPEG stream, which is AV data;
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`Fig. 3 is a schematic diagram iHustrating a VOB structure in a DVD:
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`Fig. 4 is a diagrarn illustrating a data hierarchy of a BD-ROM;
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`Fig. 5 is a diagram illustrating a structure of logical data recorded in a BD-ROM;:
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`Fig. 6 is a diagram illustrating an overview of a basic configuration of a BD-ROM
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`player that plays BD-ROMs:
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`Fig. 7 is a block diagram where the configuration of the player illustrated in Fig. 6
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`is detailed;
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`Fig. & is a diagrarn illustrating application space of a BD-ROM;
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`Fig. 9 is a diagram illustrating the configuration of an MPEG stream (VOB);
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`Fig. 10 is a diagram illustrating the configuration of packs in an MPEG stream;
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`Fig. 11 is a diagram for describing the relationship between AV data and player
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`configuration;
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`Fig. 12 is a diagrarn for describing a VOB data continuous supply model using a
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`track buffer;
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`Fig. 13 is a diagram illustrating the internal structure of a VOB management
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`information file;
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`Fig. 14 is a diagram for describing the details of VOBU information;
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`Fig. 15 is a diagram for describing an address information acquisition method
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`using a time map:
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`Fig. 16 is a diagram illustrating the configuration of a playlist:
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`Fig. 17 is a diagram illustrating the configuration of an event handler tabie;
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`Fig. 18 is a diagram ilustrating the configuration of BD.INFO which is overall BD-
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`ROM information;
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`Fig. 19 is a diagrarn illustrating the structure of a global event handler table:
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`Fig. 20 is a diagrarn illustrating an example of a time event;
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`Fig. 21 is a diagram illustrating an example of a user event due to a user having
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`operated a menu:
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`Fig. 22 is a diagrarn illustrating an example of a global event;
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`Fig. 23 is a diagram for describing the functional configuration of a program
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`processor;
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`Fig. 24 is a diagram illustrating a list of system parameters (SPRM):
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`Fig. 25 is a diagram illustrating an example of a program in an event handier
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`according to control of a menu screen having two selection buttons:
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`Fig. 26 is a diagram illustrating an example of a program in an event handler
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`relating to a menu selection user event;
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`Fig. 27 is a flowchart illustrating the flow of basic processing for playback of AV
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`data in a BD-ROM player;
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`Fig. 28 is a flowchart illustrating the flow of processing in a BD-ROM player from
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`starting to play a playlist until ending playing of the VOB;
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`Figs. 29A and 298 are flowcharis, where Fig. 29A illustrates the flow of processing
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`relating to a time event ina BD-ROM player, and Fig. 29B iustrates the flow of
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`processing relating to a user event in a BD-ROM player,
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`Fig. 30 is a flowchart illustrating the flow of processing subtitle data ina BD-ROM
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`player;
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`Figs. 31A and 318 are diagrams describing the arrays of NAL units;
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`Fig. 32 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 33 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 34 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 35 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 36 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 37 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 38 is a diagram for describing an example of MPEG-2 TS multiplexing of an
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`HDR video stream;
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`Fig. 39 is a diagrarn illustrating the structure of a subtitle stream;
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`Fig. 40 is a diagram illustrating the relationship between parameters used in
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`subtitle display control:
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`Figs. 41A through 41C are diagrams for describing management information and
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`the content thereof;
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`Figs. 42A through 42C are diagramsillustrating the data structure of a database
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`file;
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`Fig. 43 is a diagram for describing synchronous playback between an HDR video
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`stream and an enhanced video stream thereof,
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`Fig. 44 is a diagram for describing synchronous playback between an HDR video
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`stream and an enhanced video stream thereof,
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`Fig. 45 is a diagram for describing a decoder model for an HDR video stream:
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`Fig. 46 is a diagram illustrating a registration method of streams to a database file;
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`and
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`Fig. 47 is a flowchart of playback processing of a player.
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`DETAILED DESCRIPTION
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`Underlying Knowledge Forming Basis of the Present Disclosure
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`i0007] However, further improvement was needed with the aforementioned
`
`Japanese Unexamined Patent Application Publication No. 9-282848. The present
`
`Inventors found that a problem occurs relating to the technology mentionedin the
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`“Related Art’. This problem will be described below in detail.
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`f0068] Most representative of information recording media recording video data
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`is the DVD (hereinafter, may aiso be referred to as “Standard Definition” (SD-
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`DVD). A conventional DVD will be described below.
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`6009]
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`Fig. 1 is a diagram ilustrating the structure of an SD-DVD. As iustrated
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`to the lower side of Fig. 1, the DVD disc has a logical address space provided
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`between a read-in and a read-out. Volume information of a file system is recorded
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`from the beginning of the logical address space, and after that is recorded
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`application data such as video, audio, and so forth.
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`10016] The file system is an arrangement for managing data, that is stipulated by
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`Standards such as [SOS660, Universal Disc Format (UDF), and so forth, and is an
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`arrangement to express data on the disc in increments called directories or files.
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`There are file systems called File Allocation Tables (FAT) and NT File System
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`(NTFS) in everyday-use personal computers (PC} as well, whereby data recorded
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`in a hard disk are expressed on ihe computer as structures called directories or
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`files, thereby improving usability.
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`fOO11]
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`In the case of an SD-DVD, both UDF and [SO9660 file systems are used.
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`The two together are also referred to as "UDF bridge”. The recorded data is
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`arranged so that the data can be read out by a file system driver according to
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`either UDF or iSO9660. Note that the DVD used here is a ROM disc for packaged
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`media, to which writing is physically impossibie.
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`0012] Data recorded in the DVD can be viewed through the UDF bridge as
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`directories or files such as illustrated to the upper left in Fig. 1.
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`immediately below
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`the root directory CROOT"in Fig. 1) is placed a directory called “VIDEOTS", and
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`itis here that DVD application data is recorded. Application data is recorded as
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`multiple files, primary files being the following types of files.
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`VIDEOTS.iFO Disc play control information file
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`VTS_01_01FO
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`Videotitle set #1 play control information file
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`VTS_01_0.VOB
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`Videotitle set #1 stream file
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`0013] As shown in the above example, two suffixes are stipulated. "IFO" is a
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`suffix indicating that the file has play control information recorded therein, and
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`"VOB"is a suffix indicating that the file has an MPEG stream, which is audiovisual
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`{AV) daia, recorded therein.
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`f0014]
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`Play control inforrnation is information attached to the AV data, such as
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`information to realize interactivity employed with the DVD (technology to
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`dynamically change playing in response to user operations), metadata, and so
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`forth. Play control information is cornmonly referred to as navigation information
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`regarding DVDs.
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`f0015] The play control information files include the "VIDEO_TS.IFO"that
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`manages the entire disc, and the "VTS_01_0.IFO"thatis play control inforrnation
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`for individual video title sets. Note that multiple tiles, in other words, multicle
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`different movies and tunes, can be recorded in a single disc in the case of DVD.
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`Now, "01" in the file name body indicates the No. of the video title set, and in the
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`case of the video tite set #2, for example, this is "VTS_02_0.1FO".
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`0016] The upper right portion in Fig. 1 is DVD navigation space in the
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`application layer of the DVD, and is the logical structure space where the
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`aforementioned play control information is loaded.
`o
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`Information within the
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`"VIDEOTS.IFO"is loaded in the DVD navigation space as VIDEO Manager
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`information (VMGI), as well as are "VTS_01_0.1FO" and play control information
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`existing for each of other video title sets as Video Title Set Information (VTSD.
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`0017] Described in the VTSI is Program Chain information (PGC) whichis
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`information of a play sequence called Program Chain (PGC). PGC is made up of
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`a set of Cells and a type of programing information called commands.
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`6018] A Cell itself is information indicating a partial section or a whole section of
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`a VOB (short for Video Object, and indicates an MPEG stream), and playing a Cell
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`means to play the section of this VOB instructed by the Ceil.
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`6018] Commands are processed by a virtual machine of the DVD, and are
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`close io JavaScript (a registered trademark) and so forth executed in browsers to
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`display Web pages, for example. However, while JavaScript (registered
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`trademark) performs window or browser control (e.g., opening a new browser
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`window, sic.) besides logical operations, DVD command differin that they only
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`execute playback control of AV titles, e.g., instructing a chapter to play or the like,
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`for example, besides logical operations.
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`10020] A Cell has the start and end addresses (logical addresses) of a VOB
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`recorded in the disc as internal information thereof. A player reads out data using
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`the start and end address information of the VOB described in the Cell, and
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`executes playback.
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`6021]
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`Fig. 2 is an overview for describing navigation information embedded in
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`an MPEG stream, which is AV data.
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`interactivity, which is a feature of the SD-
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`DVD, is realized not only by the navigation information recorded in the
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`aforementioned “VIDEO_TS.IFO" and "VTS_07_0.IFO" and so forth. Several
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`important seis of information are muitiplexed in the VOB along with video and
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`audio data, using a dedicated carrier called navigation packs (called navi-pack or
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`NV_PCK).
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`O22] A menu screen will be described here as a simple example ofinteractivity.
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`Several buttons are shown on the menu screen, with processing to be executed
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`defined for each button when that button is selected.
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`6023] One bution is selected on the menu screen (a translucent color is
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`overlaid on the selected button in highlight that button, indicating to the user that
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`button is in a selected state), and the user can movethe button in the selected
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`state to any of the buttons above or below,to the left or to the right, using arrow
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`keys on a remote controller.
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`f0024] Using the arrow keys of the remote controller to move the highlight to the
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`button to be selected and executed, and okaying (pressing an OK key} executes
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`the program of the corresponding command. Generally, playback of a
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`corresponding tle or chapter is executed by the command.
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`6025] The upper left portion in Fig. 2 shows an overview of information stored in
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`an NV_PCK. Highlight color information, information of individual buttons, and so
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`forth, are included in the NV_PCK. Color palette information is described in the
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`highlight color information, specifying the highlight translucent color to be
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`displayed overiaid.
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`10026] Described in the button information are rectangular region information
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`which is the position information of each button, moving information from that
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`bution to other butions (specification of destination buttons corresponding to each
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`operation of the arrow keys by the user), and button command information (a
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`command to be executed whenthat button is okayed).
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`0027] The highlight on the menu screen is created as an overlaid image, as
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`ilustrated to the upper right portion in Fig. 2. The overlaid image is an object
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`where rectangular region inforrnation of button information has been given color in
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`color palette information. This overlaid image is composited with the background
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`image ilustrated at ine right portion in Fig. 2, and displayed on ihe screen.
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`fo028] The menu screen of a DVD is realized as described above. The reason
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`why part of the navigation data is embedded in the stream using an NV_PCK is as
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`follows. That is, to realize without problem processing where synchronization
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`timing readily becomes problematic, such as dynamically updating menu
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`information synchronously with the stream, for example, displaying a menu screen
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`for just five to ten minutes partway through playing a movie.
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`6029] Another major reason is to improve user operability, such as to store
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`information for supporting special playback inan NV_PCK, so that AV data can be
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`decoded and played smoothly during non-normal playback, such as fast-forward
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`and fast-rewind while playing the DVD.
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`6030]
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`Fig. 3 is a schematic diagram Hlustrating the configuration of a VOB in a
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`DVD. Data such as video, audio, and subtitles ((1) in Fig. 3) are packetized and
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`packed according to the MPEG system (ISO/EC13818-1) Standard ({2) in Fig. 3),
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`and these are multiplexed to form a single MPEG program stream ({3)in Fig. 3},
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`as Hustrated in Fig. 3. The NV_PCKs including bution commandsfor realizing
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`interactivity are also multiplexed along with these, as described above.
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`0031] A feature of multiplexing in the MPEG systern is that the individual pixels
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`of data that are multiplexed are in a bit string based on decoding order, but the bit
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`siring is not necessarily formed in playback order, that is to say decoding order,
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`among the multiplexed data, L.e., among the video, audio, and subtitles.
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`6032] This is due to a decoder model of the MPEG systern stream ((4)in Fig. 3,
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`generally referred to as System Target Decoder or STD) has decoder buffers
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`corresponding to each elementary stream after demultiplexing, that temporarily
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`siored the data until the decoding timing.
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`10033] These decoder buffers nave different sized according to each of the
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`individual elernentary streams, having 232 kB for video, 4 kB for audio, and 52 kB
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`for subtitles. Accordingly, the data input timing to each decoder buffer differs
`
`among the individual elementary streams, so there is discrepancy between the
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`order of forming the bit string as the MPEG system stream, and the timing of
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`displaying (decoding). That is to say, the subtiie data multiplexed along with the
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`video data is not necessarily decoded at the same time.
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`10034] Now, in a large-capacity recording media such as a Blu-ray (registered
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`trademark) disc, there is a possibility that extremely high-definition video
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`information can be stored. Note that Blu-ray (registered trademark) disc, is also
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`called BD or BD-ROM.
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`(6035)
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`For example, it is conceivable that video information such as 4K (video
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`information having resolution of 3840 x 2168 pixels) or HDR (high-luminance
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`video information, generally called High Dynamic Range) may be stored in a BD.
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`Note that conventional standard-luminance video information is generally called
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`SDR (Standard Dynamic Range).
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`0026] Now, there are BS where both HDR and SDR are recorded, in order to
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`play contents on both HDR-compatible televisions and HDR-incompatibie (only
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`compatible with SDR) televisions.
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`In such BDs, a problem is to simplify playback
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`control such as video stream selection and so forth. The Present Inventors
`
`studied the following improvement measures to solve the above problem.
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`{0037] Recorded in a recording medium according to an aspect of the present
`
`disclosure are a video stream of standard-luminance range, and a video stream of
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`high-luminance range that is a broader luminance range than the standard-
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`luminance range, which are used selectively in accordance with a playback
`
`environment, a subtitle stream of the standard-luminance range, and a subtitle
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`stream of the high-luminance range, which are used selectively in accordance with
`
`the playback environment, and a playlist file storing playback control inforrnation of
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`content, the playlist file including a management region where the playback control
`
`information relating to a main stream is stored, and an extended region. The
`
`management region stores first playoack control information specifying that a
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`video stream of the high-luminance range and a subtitle stream of the high-
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`luminance range are to be played in combination. The extended region stores
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`second playback control information specifying that a video stream of the
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`standard-luminance range and a subliitle strearn of the standard-luminance range
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`are to be played in combination.
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`6038] A playback device that plays a recording mediurn having such a
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`configuration can read out the first playback control information stored in the
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`management region in a case of selecting and playing a video stream of a high-
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`luminance range. On the other hand, The playback device can read out the
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`second playback control information stored in the extended region in a case of
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`selecting and playing a video stream of a standard-luminance range. Accordingly,
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`the playback device can play video streams of the standard-luminance range by
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`about the same processing as video streams of the high-luminance range.
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`f0039] Also, a subtitle stream of the high-luminance range is combined with the
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`video stream of the high-lurninance range, so a situation will not occur such as an
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`SDR subtitle stream being combined with an HDR video stream.
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`10040] Thus, according to the above recording medium, playback control such
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`as selecting video streams and so forth is simplified. According to the above-
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`described recording medium, the video stream selection processing and playback
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`processing of a playback device that can play this recording medium can be
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`simplified.
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`00471]
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`Part of the second playback control information may have a common
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`data structure with the first playback control information.
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`6042] Accordingly, the playback device can play video streams of the standard-
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`luminance range by about the sare processing as video streams of the high-
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`luminance range. This is also advantageous in that authoring by the system is
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`easy, and advantageous in that mounting/operation verification processing of the
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`player is easy (costs can be reduced).
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`f0043] The recording medium may further have recorded therein a management
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`information file including a map region storing map information indicating a
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`position of an independently decodable picture included in a video strearn, and an
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`extended map region, wherein the map region stores first map information
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`indicating @ position, in a video strearn of the high-lurminance range, of an
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`independently decodable picture included in a video stream of the highluminance
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`range, and whersin the extended map region stores second map information
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`indicating a position, in a video stream of the standard-lurminance range, of an
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`independently decodable picture included in a video stream of the standard-
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`luminance range.
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`6044] The playback device that plays a recording mediurn having such a
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`configuration can read out the first map information in the map region when
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`selecting a video stream of high-luminance range and performing random access
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`playbackof the like, and can read out the second mapinformation in the extended
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`map region when selecting an SDR video stream and performing random access
`
`playback of the like. That is to say, according to such a BD, the video stream
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`selection processing and playback processing of the playback device that plays
`
`this BD can be facilitated in cases of performing random access playback (special
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`playback) and so forth as well.
`
`f0045] The recording medium may further have recorded therein a sub-playlist
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`file storing the playback control information relating to a sub-stream played at the
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`same time as the main stream file, wherein third playback control information
`
`relating to an enhanced video stream for extending the luminance range of the
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`video stream of the high-luminance range is stored in the sub-playlist fle.
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`0046] The playback device that plays a recording medium having such a
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`configuration can read out the first control information within the management
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`region and the third control information within the sub-playlist, and thereby play the
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`video stream of high-luminance range and the enhanced stream at the same time.
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`That is to say, according to such a BD, enhancement processing of the video
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`stream in the high-luminance range by the player that plays this BD can be
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`facilitated.
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`0047] The recording medium may further have recorded therein a sub-playlist
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`file storing the playback control information relating to a sub-stream played at the
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`same time as the main stream file, wherein third playback control information
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`relating to an enhanced video stream for extending the luminance range of the
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`video stream of the high-lurninance range is stored in the sub-playlist file, and
`
`wherein the map region stores the first map information, and third map information
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`indicating a position, in the enhanced video stream, of an independently
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`decodable picture included in the enhanced video stream.
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`6048] The playback device that plays a recording mediurn having such a
`
`configuration can play a video stream of high-luminance range and an enhanced
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`stream at the same time, by reading out the first control information within the
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`management region and the third control information within the sub-playlist. That
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`is fo say, according to such a BD, enhancement processing of the video stream in
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`the high-luminance range by the playback device that plays this BD can be
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`facilitated.
`
`f0048] Also, when performing random access playback or the like, the playback
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`device can further read out just information within the map region. That is to say,
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`according to such a BD, the playback processing of the playback device that plays
`
`this BD can be facilitated in a case of enhancing the high-luminance range video
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`stream and also performing random access playbackorthe like.
`
`6080] A playback method according to an aspect of the present disclosure is a
`
`playback method of reading out and playing content from a recording mediurn in
`
`which is recorded a video stream of standard-luminance range, and a video
`
`stream of high-luminance range that is a broacler luminance range than the
`
`siandard-luminance range, which are used selectively in accordance with a
`
`playback environment, a subtitle stream of the standard-luminance ranges, and a
`
`subtite stream of the high-luminance range, which are used selectively in
`
`accordance with the playback environment, and a playlist file storing playback
`
`control information of content, the playlist file including a management region
`
`where the playback control information relating to a main stream is stored, and an
`
`extended region. The management region sioring first playback control
`
`information specifying that a video stream of the high-luminance range and a
`
`subtitie stream of the high-luminance range are to be played in combination. The
`
`extended region storing second playback control information specifying that a
`
`video stream of the standard-luminance range and a subtitle stream of the
`
`standard-luminance range are to be played in combination. The playback method
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`includes: reading out and playing a video stream of the high-luminance range and
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`a subtitle stream of the high-luminance range, based on the first playback control
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`information, in a case of playing the content as a content of the high-luminance
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`range; and reading out and playing a video stream of the standard-luminance
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`range and a subtitie stream of the standard-luminance range, based on the
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`second playback contral information, in a case of playing the content as a content
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`of the standard-luminance range.
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`f0057]
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`Part of the second playback control information may have a common
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`data structure with the first playback control information.
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`fO0S2] The recording medium may further have recorded therein a management
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`information file including a map region storing map information indicating a
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`position of an independently decodable picture included in a video stream, and an
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`extended map region, the map region storing first map information indicating a
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`position, in a video stream of the high-luminance range, of an independently
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`decodabie picture included in a video stream of the high-luminance range, and the
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`extended map region storing second map information indicating a position, ina
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`video stream of the standard-luminance range, of an independently decodable
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`picture included in a video stream of the standard-luminance range. The playback
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`method may further include: reading oul and playing a video stream of the high-
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`luminance range and a subtitle stream of the high-luminance range, based on the
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`first playback control information and the first map information, in a case of playing
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`the content as a content of the high-luminance range; and reading out and playing
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`a video stream of the standard-luminance range and a subtitle stream of the
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`siandard-luminance range, based on the second playback control information and
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`the second map information, in a case of playing the content as a content of the
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`standard-luminance range.
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`f0053] The recording medium may further have recorded therein a sub-playlist
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`file storing the playback control information relating to a sub-stream played at the
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`same time as the main stream file, and third playback control information relating
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`to an enhanced video strearn for extending the luminance range of the video
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`stream of the high-luminance range being stored in the sub-playlist file. The
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`playback method may further include: reading out and playing a video stream of
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`the high-luminance range and a subtitle stream of the high-luminance range,
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`based on the first playback control information, and also reading out and playing
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`the enhanced video stream based on the third playback control information, ina
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`case of playing the content as a content of a luminance range thai has been
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`extended beyond the high-luminance range.
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`(0054) The recording medium may further have recorded therein a sub-playlist
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`file storing the playback control information relating to a sub-stream played at the
`
`same time as the main stream file, third playback control information relating to an
`
`enhanced video stream for extending the luminance range of the video stream of
`
`the high-luminance range being stored in the sub-playlist file, and the map region
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`storing the first map information, and third map information indicating a position, in
`
`the enhanced video stream, of an independently decodable picture included in the
`
`enhanced video stream. The playback method mayfurther include: reading out
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`and playing a video stream of the high-luminance range and a subtitle stream of
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`the high-lurninance range, based on the first playback control information and the
`
`first map information, and aiso reading out and playing the enhanced video strearn
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`based on the third playback control information and the third map information, in a
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`case of playing the content as a content of a luminance range that has been
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`extended beyond the high-luminance range.
`
`10055] A playback device according to an aspect of the present disclosure is a
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`playback device that reads out and plays content from a recording medium in
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`which is recorded a video stream of standard-luminance range, and a video
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`stream of high-luminance range that is a broader luminance range than the
`
`siandard-luminance range, which are used selectively in accordance with a
`
`playback environment, a subtitle stream of the standard-luminance range, and a
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`subtitle stream of the high-luminance range, which are used selectively in
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`accordance with the playback environment, and a playlist file storing playback
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`control information of content, the playlist file including a management region
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`where the playback control information relating to a main stream is stored, and an
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`extended region. The management region storesfirst playback control information
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`specifying that a video stream of the high-luminance range and a subtitle stream of
`
`the high-luminance range are to be played in combination. The extended region
`
`stores second playoack control information specifying that a video stream of the
`
`standard-luminance range and a subtitle stream of the standard-luminance range
`
`are to be played in combination. The playback device includes: a video playback
`
`unit that (1} reads out and plays a video stream of the high-luminance range and a
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`subtite stream of the high-luminance range, based on the first playback control
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`information, in a case of playing the content as a content of the high-luminance
`
`range, and (2) reads out and plays a video strearn of the standard-luminance
`
`range and a subtitle stream of the standard-luminance range, based on the
`
`second playback control information, in a case of playing the content as a content
`
`of the standard-luminance range.
`
`6086] These general or specific aspects may be realized by a device, method,
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`system, integrated circuit, computer program, or compuier-readable recording
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`medium such as a CD-ROM, and may be realized by any combination of a system,
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`method, integrated circuit, computer program, and recording medium.
`
`0057]
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`Preferred embodiments to carry out the present disclosure will be
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`described below with reference to the attached drawings.
`
`It should be noted that
`
`the second embodimentis the closest to the disclosure in Claim 1 of the present
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`application, the basic configuration of the information recording medium