| # Schema |
|
|
| This document defines the contracts for canonical filenames and |
| `metadata.csv`. Filenames are human-readable descriptions; `record_id` is the |
| persistent machine identity. |
|
|
| ## Canonical Filename Format |
|
|
| `YYYY-MM-DD.HHMM.Tool.Medium.Support.Dimensions[.RecNN].ext` |
|
|
| Examples: |
|
|
| ```text |
| 2025-07-15.0448.FountainPen.Ink.Paper.9x12.mp4 |
| 2026-06-29.UnknownTime.FountainPen.Ink.Paper.30x40.Rec11.mp4 |
| 2026-06-29.UnknownTime.FountainPen.Ink.Paper.30x40.Rec12.mp4 |
| ``` |
|
|
| ### Filename fields |
|
|
| - `YYYY-MM-DD` — documented finish date. |
| - `HHMM` — documented finish time in 24-hour local civil time. |
| - `UnknownTime` — used when no reliable finish time is documented. |
| - `Tool` — drawing instrument, such as `Pencil`, `FountainPen`, `BallpointPen`, |
| or `Brush`. |
| - `Medium` — applied material, such as `Graphite` or `Ink`. |
| - `Support` — drawing surface, such as `Paper`, `IllustrationBoard`, or |
| `WatercolorPaper`. |
| - `Dimensions` — support dimensions in inches; order preserves support |
| orientation, such as `9x12` or `12x9`. |
| - `RecNN` — optional recording-sequence identifier used when documented order |
| must be preserved or otherwise identical filenames require distinction. |
| Numbering begins with `Rec01` and may continue across finish dates. |
| - `ext` — file extension. |
|
|
| ### Filename rules |
|
|
| - Fields are separated by periods. |
| - Style and aesthetic classifications are excluded. |
| - `TL` is excluded because time-lapse is implicit in the primary collection. |
| - `0000` is reserved for a documented midnight finish time. |
| - `RecNN` identifies recording order only. It does not by itself establish a |
| separate drawing, session, or completion state, and it does not reset merely |
| because the documented finish date changes. |
| - `UnknownTime` records uncertainty; it is not replaced by an inferred time. |
| - Paper-surface variants such as `HotPress` and `ColdPress` may remain encoded |
| in filenames until a dedicated metadata field is added. |
| - Historical relationships must not be inferred from filename similarity |
| alone. |
|
|
| Tool and medium tokens in a filename describe documented materials, but older |
| filenames do not always encode an unambiguous one-to-one pairing. Metadata must |
| therefore preserve tool and medium sets without manufacturing positional pairs. |
|
|
| ## Canonical Metadata Contract |
|
|
| `metadata.csv` indexes the validated canonical subset of MP4 files stored |
| directly in `Standard_Time_Lapses/`. Direct placement alone does not make a file |
| canonical: every released canonical file must have exactly one metadata row, |
| complete required technical fields, and the necessary rights and provenance |
| clearance. The canonical index contains 363 validated records and covers every MP4 |
| stored directly in `Standard_Time_Lapses/` at the pinned revision. |
|
|
| The canonical index does not make provenance, unresolved, pre-standard, or |
| legacy files canonical. |
|
|
| ### Identity and collection fields |
|
|
| | Field | Type | Meaning | |
| | --- | --- | --- | |
| | `file_name` | string | Repository-relative canonical video path. | |
| | `record_id` | string | Persistent identity in the form `tla-` plus 16 lowercase hexadecimal characters. | |
| | `collection_tier` | enum | `standard` for this index. | |
| | `is_canonical` | boolean | `true` for every row in this index. | |
| | `acquisition_protocol_version` | string | Protocol identifier; currently `standard-2025-07-13`. | |
|
|
| The initial `record_id` values were generated from a namespaced SHA-256 of the |
| published repository path. Once assigned, the stored value is authoritative and |
| must be retained across filename corrections or tier changes. New tooling must |
| assign an ID only when a record does not already have one. When a genuinely new |
| record is promoted from a noncanonical holding, its ID is seeded from that |
| object's prior archival path; it must not inherit an ID already attached to a |
| different object at the corrected destination path. |
|
|
| ### Pre-Standard collection contract |
|
|
| `Pre_Standard_Time_Lapses/metadata.csv` indexes the 128 direct MP4 files in that |
| folder. Each row uses `collection_tier = pre_standard`, `is_canonical = false`, |
| and a blank `acquisition_protocol_version`. Pre-Standard status records a |
| different acquisition/documentation era; it does not remove the requirements |
| for stable identity, exact content hash and size, or encoded-stream metadata. |
|
|
| Dates, times, tools, media, support, and historical provenance may remain blank |
| when the surviving evidence is insufficient. Those blanks are historical |
| uncertainty, not failed technical ingestion. |
|
|
| ### Session and material fields |
|
|
| | Field | Type | Meaning | |
| | --- | --- | --- | |
| | `date` | `YYYY-MM-DD` | Documented finish date. | |
| | `time` | `HH:MM` or blank | Documented finish time; blank means unknown. | |
| | `tool` | semicolon list | Ordered unique set of documented tools. | |
| | `medium` | semicolon list | Ordered unique set of documented media. | |
| | `support` | string | Physical drawing surface. | |
| | `dimensions` | string | Support dimensions in inches, such as `9x12`. | |
|
|
| Multiple values use semicolons: |
|
|
| ```text |
| tool = Pencil;FountainPen |
| medium = Graphite;Ink |
| ``` |
|
|
| `tool` and `medium` are independent observed-value lists. Equal lengths and |
| positional correspondence are **not guaranteed**. Repeated media are collapsed |
| to one value. A future paired representation should use a structured field and |
| must be based on documented evidence rather than token position. |
|
|
| ### Encoded-video fields |
|
|
| | Field | Type | Meaning | |
| | --- | --- | --- | |
| | `duration_seconds` | float | Encoded playback duration. | |
| | `width_px` | integer | Stored encoded width. | |
| | `height_px` | integer | Stored encoded height. | |
| | `orientation` | enum | Stored pixel orientation derived from width and height. | |
| | `encoded_frame_rate` | float | Encoded playback frame rate as reported by the container; fractional values are allowed. | |
| | `video_codec` | string | Encoded video codec. | |
| | `pixel_format` | string | Encoded pixel format. | |
| | `container` | string | Media container. | |
| | `has_audio` | boolean | Whether the stored file contains an audio stream. | |
| | `hub_xet_hash` | string | Lowercase 64-character Xet file ID from the pinned Hub resolve response's `X-Xet-Hash` header. This is distinct from the LFS-compatible SHA-256. | |
| | `size_bytes` | integer | Stored file size in bytes. | |
|
|
| These fields describe the published encoded file. They do not establish the |
| original frame-capture interval, real drawing duration, speed-up factor, camera |
| calibration, capture orientation, rotation, crop, or transcode lineage. |
|
|
| Canonical status identifies the active representative of a Standard record; it |
| does not assert that the encoded file is an unaltered or full-duration capture |
| master. A shortened derivative may be canonical when it is the verified active |
| representative and its limitation is disclosed in `notes`. |
|
|
| `encoded_frame_rate` must not be interpreted as drawing-time sampling rate. |
|
|
| ### Historical provenance fields |
|
|
| | Field | Type | Meaning | |
| | --- | --- | --- | |
| | `original_filename` | string or blank | Independently documented historical filename. | |
| | `provenance_status` | string or blank | Current relationship status. | |
| | `legacy_provenance_path` | string or blank | Verified historical repository path. | |
| | `legacy_related_references` | string or blank | Related candidates, aliases, or rejected references. | |
| | `evidence_method` | string or blank | Primary evidence used for the status. | |
| | `provenance_reference_duration_delta_seconds` | float or blank | Duration delta to a referenced historical file. | |
| | `notes` | string or blank | Human-readable evidence or qualification. | |
|
|
| Blank provenance values mean that the field is not documented or not |
| applicable in the current release. A blank must not be promoted to a verified |
| relationship. |
|
|
| Observed provenance statuses include: |
|
|
| - `legacy_match_verified` |
| - `legacy_aliases_verified` |
| - `legacy_duplicate_removed` |
| - `legacy_candidates_rejected` |
| - `direct_root_upload` |
|
|
| Observed evidence methods include: |
|
|
| - `blob_identity` |
| - `visual_continuity` |
| - `visual_comparison` |
| - `commit_history` |
| - `manual_confirmation` |
| - `blob_identity_and_physical_date` |
|
|
| New enumerated values must be documented here before use. |
|
|
| ## Physical-reference sidecar |
|
|
| `Physical_References/endpoint_references.csv` is an optional derived |
| relationship table joined to the canonical Standard index on `record_id`. It |
| must declare the exact `source_hub_revision`; it does not determine canonical |
| video status or duplicate editable video metadata. |
|
|
| Each row has a stable `reference_id`, reviewed photograph filename and role, |
| explicit surface and temporal scope, evidence state, hash state, and machine-use |
| caution. Blank values mean unknown or not documented. Version 0.1 does not |
| bundle the reference photographs, and blank proposed-path fields must not be |
| interpreted as public media locations. |
|
|
| `longitudinal_continuation` identifies a later or otherwise changed physical |
| state and is not an exact endpoint target. Two-sided references preserve |
| side-specific evidence and do not imply one shared visual target. Validators |
| must require unique identities, canonical filename agreement at the pinned |
| revision, allowed relationship values, explicit owner-confirmation state, and |
| valid SHA-256 syntax whenever a hash is present. The complete contract is in |
| [`Physical_References/SCHEMA.md`](Physical_References/SCHEMA.md). |
|
|
| ## Missing-Value Rules |
|
|
| - Blank means unknown, not documented, or not applicable according to the field |
| description. |
| - Blank numeric values must remain blank; they are not zero. |
| - Blank booleans must remain blank; they are not `false`. |
| - Uncertain dates and times must not be reconstructed from unsupported clues. |
| - Pre-Standard descriptive/provenance metadata may be less complete, but every |
| published record must carry a collection-tier distinction, stable ID, exact |
| content identity, and complete core encoded-video metadata. |
|
|
| ## Required Validation |
|
|
| Before publication, the validator must confirm: |
|
|
| - unique `record_id`, `file_name`, and nonblank `hub_xet_hash` |
| - canonical paths remain directly under `Standard_Time_Lapses/` |
| - one consistent semicolon convention for multi-value fields |
| - valid dates, times, and dimensions |
| - complete core encoded-video metadata for every active Standard and |
| Pre-Standard row |
| - orientation agrees with stored width and height |
| - canonical metadata paths match the canonical Viewer records |
| - every active standard and pre-standard metadata path resolves to a published |
| repository file |
| - repository media absent from an active index is reported explicitly rather |
| than silently treated as released data |
| - material lacking the necessary ownership or provenance clearance is absent |
| from both active indexes |
|
|
| Run: |
|
|
| ```bash |
| python tools/validate_metadata.py metadata.csv |
| ``` |
|
|
| Rebuild the v0.2 index from its pinned 335-row source and audited additions: |
|
|
| ```bash |
| python tools/repair_metadata.py source_metadata.csv metadata.csv \ |
| --additions tools/metadata_additions_v0.2.csv |
| ``` |
|
|
