Blu-ray Disc
Enable an agent to identify a Blu-ray Disc, assess its readability and recording state, and determine compatible, permitted playback, copying, recording, and preservation actions.
Research draft, second pass
A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.
recalled by Codex without web access - no source was read
Researched by: Codex
Purpose and description
Enable an agent to identify a Blu-ray Disc, assess its readability and recording state, and determine compatible, permitted playback, copying, recording, and preservation actions.
Blu-ray Disc is a family of optical disc formats that uses a nominal 405 nm blue-violet laser to read data, and in recordable variants to write data, supporting higher storage densities than DVD.
It can be Identify the disc's media type and format requirements using markings and compatible-drive reports.; Match the disc to a drive and playback environment that supports its specific requirements.; Inspect recorded organization and verify readability across a documented extent.; Record, append, or rewrite data when the media type, recording state, equipment, and authorization permit.; Create and verify an authorized preservation copy while recording unreadable regions and dependencies.; Select handling, storage, cleaning, or retirement actions from observed condition and read results..
Distinguishing features
Use media identification reported by a compatible drive, alongside packaging and markings, to distinguish Blu-ray media from visually similar CDs and DVDs.
Distinguish BD-ROM, BD-R, and BD-RE by reported media type and supported recording operations; the presence of files alone does not establish whether the disc is rewritable.
Identify a Blu-ray video release through its application-format organization and playback requirements; a Blu-ray data disc containing a video file is not automatically an authored Blu-ray video disc.
Record standard Blu-ray, Ultra HD Blu-ray, and BDXL designations separately where applicable; a generic Blu-ray label does not establish compatibility with every Blu-ray-capable device.
Separate the physical disc instance from its title or edition: two discs carrying the same work can differ in format, region restrictions, recording layout, and condition.
Scope
+ Identification of individual Blu-ray discs and their declared format variants
+ Distinctions among prerecorded BD-ROM, recordable BD-R, and rewritable BD-RE media
+ Disc capacity, recording state, and organization of recorded content
+ Compatibility between a particular disc and a drive or playback system
+ Physical condition, observed readability, and preservation actions
- Interpretation, authorship, and artistic assessment of the recorded film or other work
- Internal engineering and maintenance of optical drives and players
- Independent models of CDs, DVDs, and other optical storage families
- Full specifications of video codecs, file systems, and cryptographic systems
- Ownership and licensing of intellectual property beyond recording applicable permissions
Characteristics
- Media type
- BD-ROM | BD-R | BD-RE | unresolved Determines whether the carrier is prerecorded, recordable, or rewritable and constrains available actions.
- Format designations
- Reported or declared physical and application format designations, including BDXL or Ultra HD Blu-ray where applicable Prevents a broad Blu-ray classification from being mistaken for a complete compatibility assessment.
- Recording-layer count
- Integer count of data-bearing layers, or unknown Helps explain capacity and identifies requirements that may exceed a drive's supported media variants.
- Capacity and allocation
- Nominal capacity, reported addressable capacity, occupied space, and writable space in bytes, each with its evidence source Supports recording and migration planning without conflating advertised capacity with usable free space.
- Recording state
- Blank | recorded | appendable | closed to further recording | unresolved, interpreted according to media type Determines whether an intended recording operation is possible and whether existing data could be affected.
- Recorded organization
- Observed file system, application format, volume identifiers, and session or track information where exposed Separates physical access to sectors from the ability to locate files or play an authored release.
- Playback dependencies
- Required drive capabilities, software support, decoding support, and applicable protection or region conditions Explains why a readable disc may still fail to play in a particular system.
- Read verification
- Untested | partially read | fully read | read errors observed, with device, date, method, and tested extent Prevents successful mounting or brief playback from being treated as proof that the entire disc is recoverable.
- Physical condition
- Observed contamination, scratches, cracks, warping, or layer deterioration, with location and severity Guides handling and distinguishes visible damage from measured read failures.
- Action permissions
- Applicable owner authorization, content permissions, and organizational policies for playback, copying, recording, and disposal Keeps technical capability separate from permission to perform an operation.
Also called
Where this came from
wikidata · CC0 1.0
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 5 bundles · 9 layers · 17 findings · 28 questions.
Disc identity and format Identify the Blu-ray carrier and establish which physical and application-format claims are supported.
Blu-ray branding alone does not establish recording capability, capacity, or playback compatibility.
Carrier identification
Separate observed media identity from packaging claims and catalog descriptions.
Media type evidence
Record the evidence needed to identify the carrier as Blu-ray and distinguish BD-ROM, BD-R, and BD-RE.
- Which media type does a compatible drive report, and does it agree with the disc markings? definition
- Which identification claims come from direct inspection, drive output, packaging, or a catalog record? provenance
Format and edition boundaries
Locate the disc within the format family without confusing its physical specification with its recorded work.
Variant and content separation
Record physical format designations, application format, and edition relationships as distinct facts.
- Which evidence establishes any BDXL, Ultra HD Blu-ray, or authored Blu-ray video designation? definition
- Which identifiers describe this physical disc, and which describe the release, edition, or work stored on it? boundary
Capacity and recording Describe available storage and determine which recording operations the disc can support.
A recording decision depends on media type, occupied space, recording state, and device support together.
Storage layout
Establish the disc's reported storage extent and distinguish nominal capacity from allocation.
Capacity evidence
Capture layer count and capacity measurements with the method and units used.
- What layer count and addressable capacity are reported, and by which device or utility? measurement
- How much space is occupied or writable, and how do those measurements relate to the packaging's nominal capacity? measurement
Recording transitions
Assess the permissible transition from the disc's current state to a proposed recorded state.
Write operation eligibility
Require explicit evidence for recording, appending, erasing, or rewriting instead of inferring these capabilities from unused capacity.
- Is this disc blank, appendable, rewritable, or closed to further recording under its actual format? measurement
- Which proposed write operation is supported by both this medium and the selected drive, and what existing data would it affect? action
Content access and playback Describe how recorded sectors become accessible files or playable audiovisual content.
Physical readability, file-system access, application support, and playback authorization can fail independently.
Recorded content organization
Identify how the disc organizes data and what software is needed to interpret it.
Data versus authored video
Distinguish general file storage from an authored video application and record evidence for the distinction.
- What file system and directory structures are observable, and what application format do they support identifying? definition
- Does the disc contain an authored playback structure, ordinary media files, other data, or a combination? boundary
Playback compatibility
Evaluate the complete playback environment for the particular disc.
Compatibility and access conditions
Record media support, software requirements, and applicable access conditions without assuming they are uniform across Blu-ray releases.
- Does the selected drive and playback software support this disc's physical variant and recorded application format? action
- What region, content-protection, decoding, or output requirements are evidenced for this release and playback environment? boundary
- If playback fails, which stage fails: sector reading, file access, application interpretation, access authorization, decoding, or output? measurement
Readability and preservation Assess the physical disc and preserve recoverable content through documented, authorized actions.
A disc can look intact while containing unreadable regions, and a successful playback sample does not verify complete recovery.
Condition and read evidence
Keep visible condition separate from results obtained by reading the medium.
Readability assessment
Document defects and the extent of read testing so confidence remains tied to evidence.
- What contamination, scratches, cracks, warping, or layer changes are visible, and where are they located? measurement
- Which sectors or files were tested, with which drive and method, and where did errors or retries occur? measurement
- Would another compatible drive or an appropriate cleaning step help distinguish a disc defect from an equipment-specific failure? action
Preservation and retirement
Plan copying, retention, and retirement with explicit recovery objectives and permissions.
Verified preservation action
Specify what must survive migration and what evidence establishes that the authorized copy meets that objective.
- Must preservation retain selected files, the full logical disc structure, interactive playback behavior, or another explicitly defined property? boundary
- What authorization permits the proposed copy or disposal, and how will copied data be verified against the readable source? action
- Which unreadable regions or playback dependencies remain unresolved after copying, and do they require retaining the original disc? action
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
A model that cannot be lined up against existing standards, identifiers and practice cannot be adopted by anyone who already uses them.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- This describes the optical storage format family and physical medium; the supplied domain code does not establish a narrower sense.
- Specification editions, detailed compatibility requirements and content-protection versions require verification; no documents were consulted for this recall.
- Capacity depends on format and layer count; archival lifetime cannot be inferred from the Blu-ray designation alone.
- Which of these check these first hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Kinds and varieties
Recalled without web access and unsourced; every item is a lead to verify.
- BD-ROM: prerecorded read-only discs
- BD-R: write-once recordable discs
- BD-RE: rewritable discs
- BDXL: higher-capacity multilayer recordable and rewritable discs
- Ultra HD Blu-ray: a disc format for distributing ultra-high-definition video
- Which of these kinds and varieties hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- Blu-ray format abbreviations - BD-ROM, BD-R, BD-RE - These identify format families and recording capabilities, not individual discs or titles.
- Which of these identifiers and schemes hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Standards and regulation
Recalled without web access and unsourced; every item is a lead to verify.
- Blu-ray Disc Association format specifications define BD-ROM, BD-R and BD-RE.
- Blu-ray Disc Association BDXL specifications define higher-capacity recordable and rewritable formats.
- Blu-ray Disc Association Ultra HD Blu-ray specifications define the ultra-high-definition video distribution format.
- Universal Disk Format (UDF), maintained by the Optical Storage Technology Association, specifies a filesystem used on Blu-ray discs.
- Advanced Access Content System (AACS), specified by AACS Licensing Administrator, provides content protection used on commercial Blu-ray releases.
- Which of these standards and regulation hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Distribution of high-definition and ultra-high-definition films and television programmes
- Distribution of video games for compatible consoles
- Offline data backup and archiving
- Recording and exchange of video or other large datasets
- Which of these real-world use hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Typical measurements
Recalled without web access and unsourced; every item is a lead to verify.
- Nominal laser wavelength - 405 - nm
- Common disc diameter - 120 - mm
- Nominal disc thickness - 1.2 - mm
- Nominal conventional single-layer or dual-layer capacity - 25 or 50 - GB (decimal)
- Nominal BDXL capacity - 100 for rewritable discs; 100 or 128 for write-once discs - GB (decimal)
- Nominal Ultra HD Blu-ray capacity - 50, 66 or 100 - GB (decimal)
- Which of these typical measurements hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Scratches, fingerprints and contamination can produce read errors or prevent playback.
- Heat, sunlight, moisture and material degradation can damage discs or shorten their usable life.
- Interrupted recording, unsuitable media or a failing writer can leave recordings incomplete or unreadable.
- Drive and player compatibility varies by format; conventional Blu-ray support does not establish BDXL or Ultra HD Blu-ray support.
- Content protection, region coding or unsupported playback software can block playback of otherwise readable discs.
- Which of these failure modes and hazards hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Conventional Blu-ray video supports regions A, B and C; individual releases may permit multiple regions or all regions.
- Ultra HD Blu-ray discs do not use the conventional Blu-ray region-code system.
- Available audio tracks, subtitles, edits and supplementary material can differ between regional releases.
- Which of these regional variation hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- DVD - DVD uses a red laser and a lower-density optical format; a conventional single-layer DVD holds about 4.7 GB compared with 25 GB for Blu-ray.
- Compact Disc - CD uses an infrared laser and a lower-density format, commonly holding roughly 700 MB of data.
- HD DVD - HD DVD was a competing blue-violet-laser optical format with different disc structures and incompatible format specifications.
- Blu-ray player - A Blu-ray player is equipment that reads and plays compatible discs; Blu-ray Disc denotes the storage medium and its format family.
- Ultra HD Blu-ray - Ultra HD Blu-ray is a specialised member of the Blu-ray family with distinct video and playback requirements, rather than a synonym for every Blu-ray disc.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of Blu-ray Disc this model covers, and on what evidence? provenance
What the second pass must settle
- Which authoritative specifications should anchor the supported Blu-ray variants, capacities, layer configurations, and recording-state terminology?
- Should BDXL and Ultra HD Blu-ray remain variants within this registry entry, or do existing registry or world-model entries already own their additional requirements?
- Which drive reports and testing methods provide sufficiently reliable evidence of media identity and complete readability across the variants in scope?
- Which manufacturer or preservation guidance should govern cleaning, storage conditions, and retirement decisions for each media type?
- How should release-specific playback restrictions and preservation permissions be represented when packaging, observed behavior, and available documentation disagree?