Anthropics Technology Ltd., 22 Baseline Studios, Whitchurch Road, London W11 4AT, UK.
IEEE Trans Pattern Anal Mach Intell. 2012 May;34(5):972-86. doi: 10.1109/TPAMI.2011.168.
Portable light field (LF) cameras have demonstrated capabilities beyond conventional cameras. In a single snapshot, they enable digital image refocusing and 3D reconstruction. We show that they obtain a larger depth of field but maintain the ability to reconstruct detail at high resolution. In fact, all depths are approximately focused, except for a thin slab where blur size is bounded, i.e., their depth of field is essentially inverted compared to regular cameras. Crucial to their success is the way they sample the LF, trading off spatial versus angular resolution, and how aliasing affects the LF. We show that applying traditional multiview stereo methods to the extracted low-resolution views can result in reconstruction errors due to aliasing. We address these challenges using an explicit image formation model, and incorporate Lambertian and texture preserving priors to reconstruct both scene depth and its superresolved texture in a variational Bayesian framework, eliminating aliasing by fusing multiview information. We demonstrate the method on synthetic and real images captured with our LF camera, and show that it can outperform other computational camera systems.
便携式光场 (LF) 相机已经展示出了超越传统相机的能力。在单次拍摄中,它们能够实现数字图像重聚焦和 3D 重建。我们展示了它们可以获得更大的景深,但仍然能够以高分辨率重建细节。事实上,所有深度都几乎是聚焦的,只有一小部分区域的模糊大小受到限制,即它们的景深与常规相机相比实际上是倒置的。它们成功的关键在于它们获取 LF 的方式,在空间分辨率和角度分辨率之间进行权衡,以及混叠如何影响 LF。我们表明,由于混叠,将传统的多视图立体方法应用于提取的低分辨率视图可能会导致重建误差。我们使用显式的图像形成模型来解决这些挑战,并在变分贝叶斯框架中结合朗伯和纹理保持先验来重建场景深度及其超分辨率纹理,通过融合多视图信息消除混叠。我们在我们的 LF 相机拍摄的合成和真实图像上演示了该方法,并表明它可以胜过其他计算摄像系统。