Efficient-PIP: Large-scale Pixel-level Aligned Image Pair Generation for Cross-time Infrared-RGB Translation

Generative models are gaining momentum in both academic and industrial applications driven by the availability of large-scale datasets, especially in tasks involving Image-to-Image Translation. Meanwhile, poor human perception of nighttime environment has led to a demand for translation from night-vision infrared to day-vision RGB images. However, collecting such cross-modal training data at the same time is impossible due to the thermal imaging properties of infrared cameras, the challenge lies in constructing image pairs during the day and at night respectively, where the requirement for data alignment poses significant difficulties. In this paper, we propose a Pixel-level aligned Image Pair generation framework PIP to explore efficient colorization of high-resolution infrared images. Specifically, we first construct a 3D high-precision point cloud map for the purpose of establishing the correlation between day and night scenes. Corresponding point clouds of modal images are collected simultaneously during data acquisition to obtain image sensor poses by Global Matching with the map, which allows us to calculate the transformation relationship from infrared to RGB image coordinate systems based on the sensor parameters and depth information of the map. Leveraging the relationship, the pixel values of RGB image is projected onto the infrared image followed by optimization as the colored image. Accordingly, we present a dataset NUDT-PIP, the first of its kind containing large-scale pixel-level aligned cross-time infrared-RGB image pairs of complicated real road scenes. Experimental results demonstrate the reliability and strong applicability of our dataset in Image-to-Image Translation. Our code will be released at https://github.com/wjjjjyourFA/NUDT-PIP.