id: https://nde.nl/ontology/hc/class/VideoTimeSegment name: video_time_segment_class title: Video Time Segment Class imports: - linkml:types - ../slots/end_seconds - ../slots/end_time - ../slots/segment_index - ../slots/segment_text - ../slots/speaker_id - ../slots/speaker_label - ../slots/specificity_annotation - ../slots/start_seconds - ../slots/start_time - ../slots/has_or_had_score # was: template_specificity - migrated per Rule 53 (2026-01-17) - ./SpecificityAnnotation - ./TemplateSpecificityScore # was: TemplateSpecificityScores - migrated per Rule 53 (2026-01-17) - ./TemplateSpecificityType - ./TemplateSpecificityTypes # MIGRATED 2026-01-19: confidence → is_or_was_generated_by + GenerationEvent + ConfidenceScore - ../slots/is_or_was_generated_by - ./GenerationEvent - ./ConfidenceScore prefixes: linkml: https://w3id.org/linkml/ hc: https://nde.nl/ontology/hc/ schema: http://schema.org/ dcterms: http://purl.org/dc/terms/ crm: http://www.cidoc-crm.org/cidoc-crm/ oa: http://www.w3.org/ns/oa# ma: http://www.w3.org/ns/ma-ont# default_prefix: hc classes: VideoTimeSegment: class_uri: crm:E52_Time-Span abstract: false description: 'A temporal segment within a video, defined by start and end times. **DEFINITION**: VideoTimeSegment represents a bounded temporal portion of video content. It is the foundational unit for time-coded content including: - Subtitle/caption entries (text displayed at specific times) - Annotation segments (detected scenes, objects, faces) - Chapter markers (user-defined content sections) **DUAL TIME REPRESENTATION**: Times are stored in two formats for different use cases: | Format | Example | Use Case | |--------|---------|----------| | ISO 8601 duration | PT0M30S | Human-readable, serialization | | Seconds (float) | 30.0 | Computation, synchronization | Both representations MUST be kept in sync. The seconds format is primary for computation; ISO 8601 is derived for display/storage. **MEDIA FRAGMENTS URI (W3C)**: VideoTimeSegment aligns with W3C Media Fragments URI 1.0 specification for addressing temporal fragments of video: ``` https://example.com/video.mp4#t=30,35 ``` The `start_seconds` and `end_seconds` map directly to the `t=` parameter. **WEB ANNOTATION COMPATIBILITY**: When used as an annotation target selector: - Maps to `oa:FragmentSelector` with `conformsTo` Media Fragments - Enables interoperability with W3C Web Annotation Data Model **CIDOC-CRM E52_Time-Span**: In cultural heritage documentation: - E52_Time-Span is the extent of a time-span - Used for temporal properties of cultural objects - VideoTimeSegment extends this to media-specific temporal segments **CONFIDENCE SCORING**: For segments generated by ASR (speech recognition) or CV (computer vision): - `confidence`: 0.0-1.0 score for segment accuracy - Enables filtering by quality threshold - Critical for AI-generated transcripts and annotations **HERITAGE USE CASES**: | Use Case | Example | Start | End | |----------|---------|-------|-----| | Subtitle entry | "Welcome to the museum" | 0:30 | 0:35 | | Scene annotation | "Exhibition hall panorama" | 1:00 | 1:30 | | Chapter marker | "Introduction" | 0:00 | 2:00 | | Object detection | "Painting: Night Watch" | 3:15 | 3:20 | | Speaker change | "Curator speaking" | 5:00 | 7:30 | ' exact_mappings: - crm:E52_Time-Span - oa:FragmentSelector close_mappings: - ma:MediaFragment related_mappings: - schema:Clip slots: - end_seconds - end_time - segment_index - segment_text - speaker_id - speaker_label - specificity_annotation - start_seconds - start_time - has_or_had_score # was: template_specificity - migrated per Rule 53 (2026-01-17) - is_or_was_generated_by # MIGRATED 2026-01-19: replaces confidence slot slot_usage: start_time: range: string required: false pattern: ^PT(\d+H)?(\d+M)?(\d+(\.\d+)?S)?$ examples: - value: PT0M30S description: 30 seconds from video start - value: PT1H15M30S description: 1 hour 15 minutes 30 seconds end_time: range: string required: false pattern: ^PT(\d+H)?(\d+M)?(\d+(\.\d+)?S)?$ examples: - value: PT0M35S description: 35 seconds from video start start_seconds: range: float required: true minimum_value: 0.0 examples: - value: 30.0 description: 30 seconds from start - value: 30.5 description: 30.5 seconds (millisecond precision) end_seconds: range: float required: true minimum_value: 0.0 examples: - value: 35.0 description: 35 seconds from start segment_text: range: string required: false examples: - value: Welkom bij het Rijksmuseum description: Dutch subtitle text - value: The curator explains the painting's history description: Transcript segment segment_index: range: integer required: false minimum_value: 0 examples: - value: 0 description: First segment - value: 42 description: 43rd segment (zero-indexed) is_or_was_generated_by: range: GenerationEvent required: false inlined: true description: >- Generation event containing confidence score for ASR/CV segment accuracy. MIGRATED 2026-01-19: Replaces confidence slot with structured pattern. examples: - value: has_or_had_score: has_or_had_score: 0.95 has_or_had_method: asr_transcription description: High confidence ASR segment - value: has_or_had_score: has_or_had_score: 0.72 has_or_had_method: cv_detection description: Medium confidence, may contain errors speaker_id: range: string required: false examples: - value: SPEAKER_01 description: First identified speaker - value: curator_taco_dibbits description: Resolved speaker identity speaker_label: range: string required: false examples: - value: Narrator description: Generic speaker label - value: Dr. Taco Dibbits, Museum Director description: Specific identified speaker rules: - postconditions: description: end_seconds must be >= start_seconds comments: - Reusable time segment for subtitles, annotations, chapters - 'Dual time format: ISO 8601 for serialization, seconds for computation' - Aligns with W3C Media Fragments URI specification - Confidence scoring for AI-generated content - Speaker diarization support for multi-speaker transcripts - 'MIGRATED 2026-01-19: confidence → is_or_was_generated_by + ConfidenceScore' see_also: - https://www.w3.org/TR/media-frags/ - https://www.w3.org/TR/annotation-model/ - https://www.w3.org/ns/ma-ont - http://www.cidoc-crm.org/cidoc-crm/E52_Time-Span