What is the difference between OCM and MOM format?
Symptoms / Triggers
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You're unsure which format to use for your map data workflows.
You're seeing references to OCM and MOM and want to understand the use cases for each.
You're integrating map data and need to choose between a compact, client-oriented format and a format designed for semantic modeling and exchange.
Quick Answer
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OCM (Optimized Client Map) is a compact, client-ready format designed for fast map rendering and use within apps, while MOM (Map Object Model) is a semantic, editable, and shareable map format ideal for detailed map modeling, validation, and data analysis.
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Differences Between OCM (Optimized Client Map) and MOM (Map Object Model)
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| Feature | OCM | MOM | |--------|-----|-----| | Purpose | Fast, runtime delivery to clients for in-app use | Semantic mapping for editing, validation, and sharing | | Format | Compact binary, Protobuf-based | GeoJSON-style format based on feature objects | | Data Structure | Tiled data using the HERE tiling scheme | Hierarchical features with types, IDs, geometry, and properties | | Use Case | Client apps, caching, fast downloads | Map editing, analysis, validation | | Schema | Fixed and compiled per layer | Flexible and versioned via MOM schema | | Geometry | Split by tile for performance | Full GeoJSON-style geometry | | Semantics | Simplified for compact delivery | Strongly typed real-world entities | | Versioning | Delivered in compiled bundles | Released using YY.MM versioning for base maps |
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Step-by-Step Actions
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1. Identify Your Workflow Needs
Choose OCM if you need fast download and rendering for client or app use.
Choose MOM if you are working on map modeling, validation, or integration with HERE tools.
1. Use OCM for Performance-Centric Scenarios
Load large datasets quickly into mobile or desktop apps using the compact binary format.
Utilize tiled map layers and pre-optimized bundles to improve caching and performance.
1. Use MOM for Semantic and Analytical Work
Work with GeoJSON-style data for detailed inspection and validation of map objects.
Use MOM schema definitions to maintain strong semantic types for roads, traffic, landmarks, etc.
1. Version Your Map Releases Correctly
For OCM, use fixed bundle versions that are already compiled.
For MOM, use YY.MM versioning to track and release new map changes over time.
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Applies-to
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Users working with HERE maps in apps or embedded systems
Mapmakers and data engineers handling geospatial data workflows
Developers needing high-performance or semantically-rich map modeling
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Customer Searchable Tags
------------------------OCM, MOM, GeoJSON, Protobuf, HERE map formats, map modeling, map delivery, map validation
Updated 3 days ago