LVTSR: Learning Visible Image Texture Network for Infrared Polarization Image Super-Resolution


07 05 2024

Xianyu Wu, Xuesong Wang, Feng Huang

Fuzhou University

Abstract

The infrared polarization (IRP) Division-of-Focal-Plane (DoFP) imaging technology has received much attention, but the insufficient resolution caused by sensor size has hindered the development and application of IRP imaging technology. Meanwhile, high-resolution (HR) visible light (VIS) is relatively easy to obtain. Therefore, using VIS images as auxiliary priors to enhance the super-resolution (SR) of infrared polarization imaging is of great significance. However, compared with infrared SR, the SR of DoFP infrared polarization imaging is more challenging due to the need to reconstruct accurate polarization information. In this paper, we propose an effective multi-modal SR network and achieve end-to-end IRP SR based on the designed loss function. In addition, we establish the first benchmark dataset with a focus on multi-modal IRP SR. The dataset contains 1559 pairs of registered images, including buildings, streets, and pedestrians. Experiments on this dataset show that the proposed method and designed loss function can effectively utilize VIS images and restore the polarization information of IRP images, achieving 4x SR. The experimental results also indicate that the proposed method outperforms the competing methods in both quantitative evaluation and visual effect evaluation.

Displaying consecutive images.

In the figure above, HR refers to high-resolution images, LR refers to images downsampled four times from HR, and SR refers to super-resolution images. The first column displays infrared polarization DoFP images, the second column displays DoLP images, the third column displays AoP images, and the last column displays guided visible light images. These images were captured continuously at a specific dock.


GitHub

The code will soon be open-source code on GitHub.

Data processing code.

Our relative work.

SwinIPISR: A Super-Resolution Method for Infrared Polarization Imaging Sensors via Swin Transformer

Abstract

The performance of the emerging infrared polarization remote sensing systems is limited by the use of infrared polarization imaging sensors and cannot produce high-resolution (HR) infrared polarization images. The lack of HR infrared polarization imaging sensors and systems hinders the development and application of infrared polarization imaging technology. The existing infrared image super-resolution (SR) methods fail to improve the resolution of infrared polarization images (IRPIs) while preserving the infrared polarization information inherent in the IRPIs; thus, aiming at obtaining accurate HR infrared polarization images, this study proposed a deep-learning-based SR method, SwinIPISR, to improve infrared polarization image resolution and preserve the infrared polarization information of the target or scene. The performance of the proposed SwinIPISR was verified and compared with existing SR methods. In contrast to other methods, SwinIPISR not only improves image resolution but also retains polarization information of the scene and objects in the polarization image. Further, the impact of the network depth of SwinIPISR on the SR performance was evaluated through experiments. The experimental results confirmed the effectiveness of the proposed SwinIPISR in enhancing the image resolution and visual effects of infrared polarization images without compromising the polarization information.

Download SwinIPISR Paper in pdf
Download SwinIPISR Paper in pdf
Download SwinIPISR Paper in pdf
Download SwinIPISR Paper in pdf

Click to download a PDF of the paper.

Dataset

To build our own dataset, we captured a diverse set of visable light and infrared polarized images (VISIRPIs) using an infrared polarized camera and a visible light camera. We used the infrared polarized focal plane array LD-LW640-P produced by Xi'an Liding Optoelectronics Technology Co., Ltd. The spectral range of this infrared polarized camera is 8-14 µm, with a pixel size of 17 µm and a lens focal length of 25 mm. This infrared polarized camera has a spectral range of 8-14 µm, a pixel size of 17 µm, and a lens focal length of 25 mm, with a resolution of 640 pixels × 512 pixels. We used two different visible light cameras: the MV-CA013-20GM from Hikvision, equipped with a PYTHON1300 detector and a 16mm lens, and the BFS-U3-51S5P from FLIR, using a Sony IMX250MZR detector and a lens focal length of 25mm. The MV-CA013-20GM has a pixel size of 4.8µm and a resolution of 1280 × 1024, while the BFS-U3-51S5P has a spectral range of 300-1100nm, a pixel size of 3.45 µm, and a resolution of 2248 pixels × 2048 pixels. We used the intensity image obtained by computing the full-color polarized image as the visible light image. Using a combination of binocular cameras, we captured paired images of infrared polarized and visible light in various scenes, including pedestrians, vehicles, buildings, ships, and streets. To correct the severe distortion in the infrared polarized images, we first performed distortion correction. Then, using precise registration methods, we successfully captured 1559 sets of Vis-IRPIs with a resolution of approximately 475 × 370. The samples of the dataset are shown in the following images.

The samples of the dataset are shown in the images.
BibTeX
@article{Wang:24,
    title = {LVTSR: learning visible image texture network for infrared polarization super-resolution imaging},
    author = {Xuesong Wang and Yating Chen and Jian Peng and Jiangtao Chen and Feng Huang and Xianyu Wu},
    journal = {Opt. Express},
    volume = {32},
    number = {17},
    pages = {29078--29098},
    year = {2024},
    publisher = {Optica Publishing Group},
}