High throughput video acquisition is a challenging problem and has been drawing increasing attention. Existing high throughput imaging systems splice hundreds of sub-images/videos into high throughput videos, suffering from extremely high system complexity. Alternatively, with pixel sizes reducing to sub-micrometer levels, integrating ultra-high throughput on a single chip is becoming feasible. Nevertheless, the readout and output transmission speed cannot keep pace with the increasing pixel numbers. To this end, this paper analyzes the strength of gradient cameras in fast readout and efficient representation, and proposes a low-bit gradient camera scheme based on existing technologies that can resolve the readout and transmission bottlenecks for high throughput video imaging. A multi-scale reconstruction CNN is proposed to reconstruct high-resolution images. Extensive experiments on both simulated and real data are conducted to demonstrate the promising quality and feasibility of the proposed method.
Figures & tables
Figure 1: The 1D diagram of the principle of proposed low bit gradient based scheme. Note that the LR signal is up-sampled, so that the signal has obviously blurry effect.
Figure 2: The principle verification of the proposed method with a simple reconstruction method, (a) the LRI image (up-left in the red box) and its 8 × up-sampled image, (b) the HRG map, (c) the reconstructed HR image by Eq. ( 2 ), and (d) the ground truth.
Figure 3: The diagram of our multi-scale fusion reconstruction network. The network takes low-bit HRG map and LRI image as input, and outputs the reconstructed HR image and high-precision HRG map in two directions.
Figure 4: The reconstruction results of different HRG acquisition schemes, the first row is the schematic diagram of HRG gradient acquisition scheme. The direction of the arrow represents the direction of the gradient values. There are two directions: x and y , the length of the arrow represents the bit number of the HRG gradient map. There are three kinds of bit numbers, from short to long, representing 1 bit, 1.5 bits and 2 bits respectively. (a). 1 bit, 1 direction, (b). 1.5 bits, 1 direction, (c). 2 bits, 1 direction, (d). 1 bit, 2 directions, (e). 2 bits, 2 directions, but each pixel value in each direction will only be calculated once gradient, (f). groundtruth.
Scheme
bits
1
1.5
2
1
2
directions
1
1
1
2
2
PSNR
Set5 [ 2 ]
28.97
31.78
32.31
31.57
31.39
Set14 [ 39 ]
26.62
29.05
29.21
29.01
28.21
SSIM
Set5 [ 2 ]
0.875
0.929
0.945
0.922
0.924
Set14 [ 39 ]
0.832
0.896
0.904
0.900
0.871
TB
-
0.125
0.1875
0.250
0.250
0.250
Table 1: Experimental results with different gradient acquisition scheme.
Figure 10: Ablation study. (a). without LRI to HRG fusion connection, (b). without multi-scale in gradient branches, (c). without gradient branch in x direction, (d). full model, (e). groundtruth.
Motion degradation, manifested as blur in global shutter (GS) images or rolling shutter (RS) distortion in RS counterparts, remains a fundamental challenge in computational imaging, especially under fast motion or low-light conditions. While prior works have treated blur decomposition and RS temporal super-resolution as separate tasks, this separation fails to exploit their intrinsic complementarity. In this paper, we propose a unified framework to invert motion degradation and reenact imaging moment by jointly leveraging the complementary characteristics of GS blur and RS distortion. To this end, we introduce a novel dual-shutter setup that captures synchronized blur-RS image pairs and demonstrate that this combination effectively resolves temporal and spatial ambiguities inherent in both modalities. For allowing flexible performance-cost trade-offs, we further extend this dual-shutter setup to a stereo Blur-RS configuration with a narrow baseline. In addition, we construct a triaxial imaging system to collect a real-world dataset with aligned GS-RS pairs and ground-truth high-speed frames, enabling robust training and evaluation beyond synthetic data. Our proposed network explicitly disentangles motion into context-aware and temporally-sensitive representations via a dual-stream motion interpretation module, followed by a self-prompted frame reconstruction stage. Extensive experiments validate the superiority and generalizability of our approach, establishing a new paradigm for realistic high-speed video reconstruction under complex motion degradations. Codes and more resources are available at https://jixiang2016.github.io/dualBR_site/.
Xiang Ji, Guixu Lin, Zhengwei Yin +2
Graduate School of Information Science and Technology, The University of Tokyo, Japan
The task of capturing and rendering 3D dynamic scenes from 2D images has become increasingly popular in recent years. However, most conventional cameras are bandwidth-limited to 30-60 FPS, restricting these methods to static or slowly evolving scenes. While overcoming bandwidth limitations is difficult for general scenes, recent years have seen a flurry of computational imaging methods that yield high-speed videos using conventional cameras for specific applications (e.g., motion capture and particle image velocimetry). However, most of these methods require modifications to a camera's optics or the addition of mechanically moving components, limiting them to a single-view high-speed capture. Consequently, these methods cannot be readily used to capture a 3D representation of rapid scene motion. In this paper, we propose a novel method to capture and reconstruct a volumetric representation of a high-speed scene using only unaugmented low-speed cameras. Instead of modifying the hardware or optics of each individual camera, we encode high-speed scene dynamics by illuminating the scene with a rapid, sequential color-coded sequence. This results in simultaneous multi-view capture of the scene, where high-speed temporal information is encoded in the spatial intensity and color variations of the captured images. To construct a high-speed volumetric representation of the dynamic scene, we develop a novel dynamic Gaussian Splatting-based approach that decodes the temporal information from the images. We evaluate our approach on simulated scenes and real-world experiments using a multi-camera imaging setup, showing first-of-a-kind high-speed volumetric scene reconstructions.
We address the problem of recovering high-speed videos from dynamic scenes under extreme photon sparsity. Existing methods rely on aggregating photon detections in local spatiotemporal windows to improve signal-to-noise ratio; however, this local grouping discards global structure and fails in low-light regimes where photon detections are sparse in space and time. In this work, we show that the information needed to recover both motion and illumination is encoded in correlations over the full space-time pattern of photon arrivals. Building on this insight, we develop a spatiotemporal flux probing theory and an algorithm that estimates the Fourier coefficients of the underlying intensity directly from the photon stream. We demonstrate that our approach (1) recovers fast motion and temporal illumination dynamics with substantially fewer photons than prior methods, (2) enables velocity-selective videography that automatically refocuses video onto specific detected motions, and (3) generalizes across sensing modalities including single-photon, event, and spike cameras.
Jerry Yan, Matteo Forlivesi, Bowen Tan +3
Dept. of Computer Science, Purdue University · Dept. of Computer Science, University of Toronto · MIT Media Lab, Massachusetts Institute of Technology