Mobile Augmented Reality–Driven Living Transmission of Intangible Cultural Heritage along the Grand Canal

New pathways for immersive presentation and community participation in the living transmission of intangible cultural heritage along the Grand Canal are provided by mobile augmented reality. However, severe challenges to spatial registration accuracy, robustness to network disconnection, and content update mechanisms are posed by weak network coverage in linear heritage environments, limited mobile-device computing power, and the need for intangible cultural heritage content to grow dynamically. A mobile augmented reality method centered on semantic anchors was proposed. Semantic anchors were generated through joint factor graph optimization of lightweight visual semantic features and global navigation satellite system/inertial measurement unit measurements, forming a geographically consistent and compact spatial index. Each anchor was stored compactly at the hundreds-of-bytes level, and decimeter-level spatial registration was achieved without prebuilt high-precision maps. On this basis, a device-edge-cloud collaborative architecture was constructed. Semantic anchors were simultaneously employed as persistent primitives for cross-session pose recovery and as spatial containers for user-generated intangible cultural heritage micro-narratives so that second-level relocalization and continuous display were supported under fully disconnected conditions. Through edge-side lightweight quality assessment and context-aware recommendation, community-based accumulation and targeted distribution of living content were achieved. It is demonstrated by the experimental results that, for mobile augmented reality-driven living transmission of large-scale linear cultural heritage, a lightweight, robust, and engineering-feasible technical pathway is provided by the semantic-anchor method.