Event cameras sense the intensity changes asynchronously and produce event streams with high dynamic range and low latency. This has inspired research endeavors utilizing events to guide the challenging video superresolution (VSR) task. In this paper, we make the first attempt to address a novel problem of achieving VSR at random scales by taking advantages of the high temporal resolution property of events. This is hampered by the difficulties of representing the spatial-temporal information of events when guiding VSR. To this end, we propose a novel framework that incorporates the spatial-temporal interpolation of events to VSR in a unified framework. Our key idea is to learn implicit neural representations from queried spatial-temporal coordinates and features from both RGB frames and events. Our method contains three parts. Specifically, the Spatial-Temporal Fusion (STF) module first learns the 3D features from events and RGB frames. Then, the Temporal Filter (TF) module unlocks more explicit motion information from the events near the queried timestamp and generates the 2D features. Lastly, the SpatialTemporal Implicit Representation (STIR) module recovers the SR frame in arbitrary resolutions from the outputs of these two modules. In addition, we collect a real-world dataset with spatially aligned events and RGB frames. Extensive experiments show that our method significantly surpasses the prior-arts and achieves VSR with random scales, e.g., 6.5. Code and dataset are available at https: //vlis2022.github.io/cvpr23/egvsr.
翻译:事件相机以异步方式感知强度变化,并产生具有高动态范围和低延迟的事件流。这启发了利用事件来指导复杂的视频超分辨率(VSR)任务的研究。在本文中,我们首次尝试通过利用事件的高时空分辨率特性,解决随机尺度下的VSR问题。当在VSR中引导时,表示事件的时空信息是困难的。为此,我们提出了一个新颖的框架,将事件的时空插值与VSR相结合在一个统一的框架中。我们的主要思想是从RGB帧和事件中查询的时空坐标和特征中学习隐式神经表示。我们的方法包含三个部分。具体而言,首先,时空融合(STF)模块从事件和RGB帧中学习3D特征。然后,时间滤波(TF)模块从查询时间戳附近事件中产生更显式的运动信息并生成2D特征。最后,空间-时间隐式表示(STIR)模块从这两个模块的输出中恢复任意分辨率的SR帧。此外,我们收集了一个真实世界的数据集,其中包含空间对齐的事件和RGB帧。广泛的实验证明,我们的方法显著优于之前的研究,并实现了随机尺度(例如,6.5)的VSR。代码和数据集可在https://vlis2022.github.io/cvpr23/egvsr获取。