Saved in:
Bibliographic Details
Main Authors: Li, Tianqi, Fang, Wenyu, He, Xin, Geng, Xue, Cheng, Xu, Liu, Yun
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2604.16855
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910143253315584
author Li, Tianqi
Fang, Wenyu
He, Xin
Geng, Xue
Cheng, Xu
Liu, Yun
author_facet Li, Tianqi
Fang, Wenyu
He, Xin
Geng, Xue
Cheng, Xu
Liu, Yun
contents Camouflaged object detection (COD) segments objects that intentionally blend with the background, so predictions depend on subtle texture and boundary cues. COD is often needed under tight on-device memory and latency budgets, making low-bit inference highly desirable. However, COD is unusually hard to quantify aggressively. We study post-training W4A4 quantization of Transformer-based COD and find a task-specific cliff: heavy-tailed background tokens dominate a shared activation range, inflating the step size and pushing weak-but-structured boundary cues into the zero bin. This exposes a token-local bottleneck -- remove cross-token range domination and bound the zero-bin mass under 4-bit activations. To address this, we introduce COD-TDQ, a COD-aware Token-group Dual-constraint activation Quantization method. COD-TDQ addresses this token-local bottleneck with two coupled steps: Direct-Sum Token-Group (DSTG) assigns token-group scales to suppress cross-token range domination, and Dual-Constraint Range Projection (DCRP) projects each token-group clip range to keep the step-to-dispersion ratio and the zero-bin mass bounded. Across four COD benchmarks and two baseline models (CFRN and ESCNet), COD-TDQ consistently achieves an Sαscore more than 0.12 higher than that of the state-of-the-art quantization method without retraining. The code will be released.
format Preprint
id arxiv_https___arxiv_org_abs_2604_16855
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle When W4A4 Breaks Camouflaged Object Detection: Token-Group Dual-Constraint Activation Quantization
Li, Tianqi
Fang, Wenyu
He, Xin
Geng, Xue
Cheng, Xu
Liu, Yun
Computer Vision and Pattern Recognition
Camouflaged object detection (COD) segments objects that intentionally blend with the background, so predictions depend on subtle texture and boundary cues. COD is often needed under tight on-device memory and latency budgets, making low-bit inference highly desirable. However, COD is unusually hard to quantify aggressively. We study post-training W4A4 quantization of Transformer-based COD and find a task-specific cliff: heavy-tailed background tokens dominate a shared activation range, inflating the step size and pushing weak-but-structured boundary cues into the zero bin. This exposes a token-local bottleneck -- remove cross-token range domination and bound the zero-bin mass under 4-bit activations. To address this, we introduce COD-TDQ, a COD-aware Token-group Dual-constraint activation Quantization method. COD-TDQ addresses this token-local bottleneck with two coupled steps: Direct-Sum Token-Group (DSTG) assigns token-group scales to suppress cross-token range domination, and Dual-Constraint Range Projection (DCRP) projects each token-group clip range to keep the step-to-dispersion ratio and the zero-bin mass bounded. Across four COD benchmarks and two baseline models (CFRN and ESCNet), COD-TDQ consistently achieves an Sαscore more than 0.12 higher than that of the state-of-the-art quantization method without retraining. The code will be released.
title When W4A4 Breaks Camouflaged Object Detection: Token-Group Dual-Constraint Activation Quantization
topic Computer Vision and Pattern Recognition
url https://arxiv.org/abs/2604.16855