Autonomous systems require robust low-latency perception under rapidly changing scene dynamics and challenging illumination. In event cameras object detection commonly relies on recurrent architectures to accumulate sparse temporal information over time. This work investigates how temporal information can be encoded directly within the event representation. We propose a confidence-normalized continuous multi-timescale representation based on logarithmic B-spline temporal encoding together with a geometry-aware local confidence mechanism that exploits the spatial structure of event generation. Using a fixed feed-forward EventCenterNet detector, we show that the proposed representations consistently outperform the compact CSTR representation on PEDRo and Gen1 datasets. We further introduce a recursive exponential-polynomial approximation that enables efficient event-by-event updates while largely preserving detection performance. These results demonstrate that carefully designed event representations can capture a substantial portion of the temporal information learned through recurrent temporal modeling, providing a promising foundation for efficient feed-forward, event-driven, and future neuromorphic object detection.
Figures & tables
Figure 1: Temporal structure of the proposed logarithmic B-spline representation. (a) Four Second-order logarithmic B-spline functions for τ0=1.2 and τmax=35 . (b) Correlation matrix of logarithmic B-spline (left) and exponential decay (right) temporal functions, showing that the B-spline functions produce a less redundant multi-timescale encoding.
Table 1: Comparison of temporal representations on PEDRo and Gen1. PEDRo models use a 40 ms event window, while Gen1 models use a 50 ms window. Only the event representation is changed within each dataset. Four temporal functions are used for both exponential and spline-based representations.
Figure 3: Qualitative comparison of CSTR, exponential decay, and logarithmic spline representations on PEDRo. Each row shows one test example with predictions (red), annotations (green), and detector heatmaps. Exponential and spline representations are averaged over four temporal scales; red/green encode polarity support and blue local temporal confidence.
Window size (ms)
τ0 (ms)
τmax (ms)
AP 50:95
AP 50
AP 75
AP s
50
1.2
35
0.365
0.646
0.352
0.282
150
1.2
75
0.387
0.678
0.386
0.318
300
1.2
90
0.389
0.673
0.392
0.324
150
1.2
75
0.387
0.678
0.386
0.318
150
0.6
75
0.406
0.691
0.409
0.335
150
0.45
75
0.399
0.680
0.402
0.321
Table 2: Influence of window size and temporal function placement on Gen1. All models use four second-order logarithmic B-spline functions with local confidence support. All models were trained for 20 epochs using the same training configuration.
Window size (ms)
τ0 (ms)
τmax (ms)
AP 50:95
AP 50
AP 75
AP s
40
0.6
20
0.633
0.913
0.747
0.024
40
0.6
35
0.627
0.906
0.750
0.002
40
1.2
20
0.620
0.904
0.733
0.021
40
1.2
35
0.630
0.915
0.752
0.062
40
2.4
20
0.631
0.911
0.745
0.032
40
2.4
35
0.628
0.910
0.747
0.025
Table 3: Influence of temporal function placement on PEDRo. All models use four second-order logarithmic B-spline functions and local confidence support. All models were trained for 120 epochs using the same training configuration.
Figure 4: Qualitative visualization of the logarithmic spline representation on Gen1 using a 150 ms event window. Columns show the averaged representation with predictions (red) and annotations (green), the detector heatmap, and the four spline channels spanning 0.6–75 ms. Red/green denote confidence-weighted polarity support and blue denotes local temporal confidence.
Method
Coeff.
MSE ↓
AP 50:95
AP 50
AP 75
AP s
AP m
AP l
Analytical spline
Exact
–
0.636
0.918
0.752
0.111
0.618
0.674
2nd order approx.
9
1.44×10−5
0.624
0.914
0.739
0.091
0.603
0.665
4th order approx.
34
1.03×10−6
0.626
0.913
0.739
0.087
0.607
0.667
Table 4: Performance of recursive exponential-polynomial approximation of the logarithmic B-spline representation on PEDRo.
Dataset
Model
Recurrent.
Temporal context
Params
AP 50
AP 50:95
PEDRo
EventCenterNet (Ours)
No
40 ms
25M
0.918
0.636
YOLOv8x [ 25 ]
No
40 ms
58M
0.895
0.586
ReYOLOv8n [ 25 ]
Yes
200 (40 × 5) ms
4.7M
0.878
0.639
ReYOLOv8s [ 25 ]
Yes
200 (40 × 5) ms
8.3M
0.905
0.655
ReYOLOv8m [ 25 ]
Yes
200 (40 × 5) ms
18.1M
0.908
0.692
Gen1
EventCenterNet (Ours)
No
150 ms
25M
0.691
0.406
Table 5: Comparison with feed-forward and recurrent YOLO-based detectors. ReYOLO AP 50 and AP 50:95 values were obtained by re-evaluating the released models using the original evaluation protocol [ 25 ] , reproducing the published AP 50:95 results.
Method
AP 50:95
AP 50
AP 75
Spline + local conf.
0.636
0.918
0.752
+ Kalman, center + size
0.635
0.911
0.752
+ Kalman, size only
0.639
0.918
0.757
Table 6: Kalman-based temporal filtering on PEDRo.
Event cameras provide microsecond-level temporal resolution, low latency, and high dynamic range, offering potential for perception under fast motion and challenging illumination conditions. However, existing Event-based Object Detection (EOD) methods face limitations at both the representation and model levels: prior event representations usually encode temporal information indirectly through redundant structures, while detection models struggle to explicitly aggregate fragmented event responses into coherent high-order object features. To address these limitations, we present Event Dual Temporal-Relational Aggregation Detector (Ev-DTAD), a unified EOD framework that integrates representation-level temporal encoding with model-level temporal-hypergraph reasoning. Specifically, we introduce Hierarchical Temporal Aggregation (HTA), a compact three-channel pseudo-RGB representation that explicitly embeds temporal information across intra- and inter-window events. To further enhance detection under sparse and fragmented event responses, we propose Frequency-aware Hypergraph Temporal Fusion (FHTF), which refines multi-scale event features through temporal evolution modeling and high-order relational reasoning. Extensive experiments on Gen1 (+0.8 mAP and 1.7× faster), 1Mpx/Gen4 (+0.5 mAP and 1.6× faster), and eTraM (+3.0 mAP and 2.0× faster) demonstrate that Ev-DTAD achieves a competitive accuracy-efficiency trade-off, validating the complementarity between compact temporal representation and temporal-hypergraph feature reasoning.
Meisen Wang, Hao Deng, Wei Bao +5
1Xi’an Jiaotong University · 2Tsinghua University · 3China Mobile System Integration +1
Event cameras are bio-inspired sensors that asynchronously capture logarithmic intensity changes, offering inherent advantages in high-speed and high-dynamic-range scenarios. However, the sparse and asynchronous nature of event streams poses a fundamental challenge for modern deep learning architectures. To enable compatibility with standard models, most existing approaches partition the accumulation window into fixed temporal sub-bins. While effective for spatial processing, this internal discretization discards fine-grained temporal structure and constrains inference to the low temporal frequencies imposed by training supervision. To address this limitation, we propose FATE, a unified framework built upon a novel Pillar Encoding (PE). While operating over discrete macro-accumulation windows dictated by the target frequency, PE avoids internal temporal sub-binning. It organizes events into spatial pillars and approximates their intra-window evolution via projection onto a continuous-time orthogonal polynomial basis. This formulation yields an L2-optimal representation that retains rich temporal dynamics in a dense pseudo-image, mitigating information loss under sparse event conditions. To fully leverage this representation, we introduce Frequency-Aware Training (FAT), a soft mean-teacher curriculum that generates temporally dense pseudo-labels, effectively bridging the mismatch between low-frequency supervision and high-frequency inference. Extensive experiments demonstrate that FATE generalizes across architectural paradigms and consistently outperforms strong baselines. It enables robust object detection at high temporal resolutions up to 200 Hz, while incurring minimal overhead in parameter count and inference latency
Md Tawheedul Islam Bhuian, Kyoung-Don Kang
School of Computing State University of New York at Binghamton
Event cameras capture dynamic scenes with exceptional temporal fidelity by representing them as a continuous stream of microsecond resolution events. Each individual event, however, only carries minimal semantic value, merely signaling a localized brightness change. To derive meaningful signals, downstream algorithms need to quickly integrate cues from a potentially massive torrent of low-information events. Current architectures, however, are easily overwhelmed, struggling to balance capturing fine-grained temporal dynamics and maintaining a manageable data throughput. This paper proposes a framework to re-tokenize event streams into a small set of highly informative neural events, each representing a local spatio-temporal context window with a discrete learnable code. Every time this code flips, a neural event is triggered, yielding a highly compressed data stream. We demonstrate that, across object detection and classification, networks trained on neural events are on par or surpass the performance of state-of-the-art approaches while reducing the event rate by a factor of 2.0.
Roberto Pellerito, Daniel Gehrig, Shintaro Shiba +1
Robotics and Perception Group, University of Zurich · University of Pennsylvania · The University of Tokyo +1