Thoughts on Objectives of Sparse and Hierarchical Masked Image Model
Asahi Miyazaki, Tsuyoshi Okita
TL;DR
This work investigates how masking pattern choices in masked image modeling affect pretraining when using SparK's sparse, hierarchical backbone. It introduces Mesh Mask as an alternative to common masking patterns and evaluates its impact on downstream brain CT tumor detection. Across experiments, SparK generally outperforms SimCLR and MFF, with patch-level masking (random and mesh) yielding stronger results than block-level schemes, though mesh masking remains competitive with random masking and is sensitive to data augmentation. The findings guide masking-pattern design in MIM, with practical implications for medical-imaging pretraining and representation learning.
Abstract
Masked image modeling is one of the most poplular objectives of training. Recently, the SparK model has been proposed with superior performance among self-supervised learning models. This paper proposes a new mask pattern for this SparK model, proposing it as the Mesh Mask-ed SparK model. We report the effect of the mask pattern used for image masking in pre-training on performance.
