OSCAR

KNU PRMI Lab

Overview

OSCAR (Optical-aware Semantic Control for Aleatoric Refinement) is a novel framework for converting Synthetic Aperture Radar (SAR) imagery into photorealistic optical images. This work addresses the fundamentally ill-posed problem of SAR-to-optical translation.

Key Challenge
Translating SAR observations into photo-realistic optical images is fundamentally ill-posed due to speckle noise, geometric distortions, semantic misinterpretation, ambiguous texture synthesis, and structural hallucinations.

Approach

OSCAR integrates three core innovations:

Component Description
Cross-Modal Semantic Alignment Establishes an Optical-Aware SAR Encoder by transferring robust semantic knowledge from an optical reference model to the SAR processor
Semantically-Grounded Generative Guidance Implements a specialized ControlNet combining class-aware text prompts for broader context with hierarchical visual prompts for local spatial direction
Uncertainty-Aware Objective Explicitly models aleatoric uncertainty to dynamically adjust reconstruction focus, addressing speckle-induced ambiguity challenges

Key Results

OSCAR achieves superior perceptual quality and semantic consistency compared to state-of-the-art approaches through experimental validation.


Project Site


Resources

(Lee et al., 2026)

References

2026

  1. oscar.png
    OSCAR: Optical-aware Semantic Control for Aleatoric Refinement in Sar-to-Optical Translation
    Hyunseo Lee, Sang Min Kim, Ho Kyung Shin, and 2 more authors
    In , Jan 2026