Papers › SSUL: Semantic Segmentation with Unknown Label for Exemplar-based Class-Incremental Learning
SSUL: Semantic Segmentation with Unknown Label for Exemplar-based Class-Incremental Learning
Sungmin Cha, Beomyoung Kim, Youngjoon Yoo, Taesup Moon
This paper introduces a solid state-of-the-art baseline for a class-incremental semantic segmentation (CISS) problem. While the recent CISS algorithms utilize variants of the knowledge distillation (KD) technique to tackle the problem, they failed to fully address the critical challenges in CISS causing the catastrophic forgetting; the semantic drift of the background class and the multi-label prediction issue. To better address these challenges, we propose a new method, dubbed SSUL-M (Semantic Segmentation with Unknown Label with Memory), by carefully combining techniques tailored for semantic segmentation. Specifically, we claim three main contributions. (1) defining unknown classes within the background class to help to learn future classes (help plasticity), (2) freezing backbone network and past classifiers with binary cross-entropy loss and pseudo-labeling to overcome catastrophic forgetting (help stability), and (3) utilizing tiny exemplar memory for the first time in CISS to improve both plasticity and stability. The extensively conducted experiments show the effectiveness of our method, achieving significantly better performance than the recent state-of-the-art baselines on the standard benchmark datasets. Furthermore, we justify our contributions with thorough ablation analyses and discuss different natures of the CISS problem compared to the traditional class-incremental learning targeting classification. The official code is available at https://github.com/clovaai/SSUL.
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Tasks
1 archive task tag without a task page not shown.
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| Disjoint 10-1 | PASCAL VOC 2012 | SSUL-M | mIoU | 53.50 | #1 of 8 | Archive leaderboard | report |
| Disjoint 10-1 | PASCAL VOC 2012 | SSUL | mIoU | 50.87 | #2 of 8 | Archive leaderboard | report |
| Disjoint 15-1 | PASCAL VOC 2012 | SSUL-M | mIoU | 68.58 | #2 of 9 | Archive leaderboard | report |
| Disjoint 15-1 | PASCAL VOC 2012 | SSUL | mIoU | 64.01 | #3 of 9 | Archive leaderboard | report |
| Disjoint 15-5 | PASCAL VOC 2012 | SSUL-M | Mean IoU | 69.83 | #2 of 9 | Archive leaderboard | report |
| Disjoint 15-5 | PASCAL VOC 2012 | SSUL | Mean IoU | 69.10 | #3 of 9 | Archive leaderboard | report |
| Overlapped 10-1 | PASCAL VOC 2012 | SSUL-M | mIoU | 64.12 | #3 of 13 | Archive leaderboard | report |
| Overlapped 10-1 | PASCAL VOC 2012 | SSUL | mIoU | 59.25 | #6 of 13 | Archive leaderboard | report |
| Overlapped 100-5 | ADE20K | SSUL-M | mIoU | 34.56 | #2 of 8 | Archive leaderboard | report |
| Overlapped 100-5 | ADE20K | SSUL | mIoU | 32.48 | #3 of 8 | Archive leaderboard | report |
| Overlapped 100-50 | ADE20K | SSUL-M | mIoU | 34.37 | #4 of 7 | Archive leaderboard | report |
| Overlapped 100-50 | ADE20K | SSUL | mIoU | 33.58 | #5 of 7 | Archive leaderboard | report |
| Overlapped 15-1 | PASCAL VOC 2012 | SSUL-M | mIoU | 71.37 | #4 of 13 | Archive leaderboard | report |
| Overlapped 15-1 | PASCAL VOC 2012 | SSUL | mIoU | 67.61 | #5 of 13 | Archive leaderboard | report |
| Overlapped 15-5 | PASCAL VOC 2012 | SSUL-M | Mean IoU (val) | 73.02 | #4 of 13 | Archive leaderboard | report |
| Overlapped 15-5 | PASCAL VOC 2012 | SSUL | Mean IoU (val) | 71.22 | #7 of 13 | Archive leaderboard | report |
| Overlapped 50-50 | ADE20K | SSUL-M | mIoU | 29.77 | #5 of 7 | Archive leaderboard | report |
| Overlapped 50-50 | ADE20K | SSUL | mIoU | 29.56 | #6 of 7 | Archive leaderboard | report |
Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.
Methods
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