# SemFormer: Semantic Guided Activation Transformer for Weakly Supervised Semantic Segmentation Source: [SemFormer: Semantic Guided Activation Transformer for Weakly Supervised Semantic Segmentation]() Collection index: [llms.txt]() Data updated: 2025-10-27T06:18:29.550Z Authors: Junliang Chen, Xiaodong Zhao, Cheng Luo, Linlin Shen Published: 2022-10-26T10:51:20.000Z ## Abstract Recent mainstream weakly supervised semantic segmentation (WSSS) approaches are mainly based on Class Activation Map (CAM) generated by a CNN (Convolutional Neural Network) based image classifier. In this paper, we propose a novel transformer-based framework, named Semantic Guided Activation Transformer (SemFormer), for WSSS. We design a transformer-based Class-Aware AutoEncoder (CAAE) to extract the class embeddings for the input image and learn class semantics for all classes of the dataset. The class embeddings and learned class semantics are then used to guide the generation of activation maps with four losses, i.e., class-foreground, class-background, activation suppression, and activation complementation loss. Experimental results show that our SemFormer achieves \\textbf{74.3}\\% mIoU and surpasses many recent mainstream WSSS approaches by a large margin on PASCAL VOC 2012 dataset. Code will be available at \\url{https://github.com/JLChen-C/SemFormer}. ## Recorded benchmark results A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage. ## Original sources and implementation [Original paper]() [PDF]()