NSM2-SED: a non-scanning Mamba-2 model for sound event detection
摘要
Transformer architectures have found widespread application in sound event detection (SED). However, due to its high computational complexity, most models employ a fixed context window, which hinders the modeling of long-range dependencies beyond the window boundaries. Mamba alleviates the limitation of fixed attention windows, but its inference remains constrained by sequential scanning, which limits parallelization efficiency. In this study, we propose NSM2-SED, a non-scanning structured state duality based Mamba-2 architecture for SED. The mean teacher (MT) model is used as the baseline system. Initially, we pre-train the NSM2 module on AudioSet and run it in parallel with a CNN-based feature extractor to capture a broader spectrum of audio features. Subsequently, a two-stage training strategy is adopted: in stage 1, the NSM2 module is frozen, while the CRNN is trained for effective component interaction; in stage 2, all parameters are fine-tuned jointly. Our experiments demonstrate that, NSM2-SED achieves performance comparable to, and in some cases surpasses, that of Transformer-based models, while requiring fewer parameters. And the proposed method achieved 0.510/0.762 PSDS1/PSDS2 in the DESED dataset, significantly outperforming the baseline results of 0.385/0.593. The source code has been released at https://github.com/lchenglong789-cell/NSM2-SED.git.