MI-DETR: A Strong Baseline for Moving Infrared Small Target Detection with Motion Integration
Authors: Nian Liu, Jin Gao, Zhen Liang, Shubo Lin, Sikui Zhang, Fudong Ge, Liang Li, Weiming Hu
Organizations: School of Advanced Interdisciplinary Sciences (SAIS), University of Chinese Academy of Sciences (UCAS), Beijing 101408, China · State Key Laboratory of Multimodal Artificial Intelligence Systems, Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China · School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing 101408, China · Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China · University of Chinese Academy of Sciences (UCAS), Beijing 100049, China · Beijing Institute of Basic Medical Sciences, Beijing 100850, China · School of Information Science and Technology, ShanghaiTech University, Shanghai 201210, China
Detecting moving infrared small targets is challenging because tiny, low-contrast targets occupy few pixels and are easily obscured by dynamic backgrounds. Existing multi-frame methods aggregate temporal information across frames to capture motion. However, dynamic background changes can generate similar motion cues, making it difficult to distinguish between target motion and background interference. Furthermore, even when motion cues are extracted, combining them with current-frame appearance features remains difficult. To address these issues, we propose Motion Integration DETR (MI-DETR), a three-stage framework that explicitly models motion and fuses it with appearance features. First, to suppress background clutter while preserving target-related motion cues, Recurrent Interpretable Motion Cue Aggregation (RIMCA) maintains a recurrent temporal state that accumulates motion across consecutive frames, producing a causal and spatially aligned motion representation. Second, to integrate spatial and temporal information, Pathway Mutual Interaction (PMI) preserves separate appearance and motion pathways while enabling bidirectional feature exchange between them. Finally, an RT-DETR-based detector uses these refined features for end-to-end target localization. Experiments on DAUB-R, ITSDT-15K, and IRDST-H show that explicit motion modeling and pathway interaction effectively improve moving infrared small target detection.
Figures & tables
Fig. 1: MI-DETR combines 70.30% mAP 50 with 34.60 FPS on IRDST-H under the unified RTX 3090 protocol [ 7 ] .
Fig. 2: Overall architecture of MI-DETR. RIMCA constructs the motion representation, PMI performs bidirectional interaction between the appearance and motion pathways, and RT-DETR performs the final target classification and localization.
Fig. 3: Qualitative visualization of RIMCA over five consecutive infrared frames. (a, b) Appearance inputs without and with ground-truth (GT) annotations. (c, d) Corresponding RIMCA motion representations without and with GT annotations. Red boxes indicate GT targets, and blue boxes denote zoom-in regions.
Dataset
Train
Val
Test
Total
ITSDT-15K [ 43 ]
10,000
–
5,000
15,000
IRDST-H [ 28 ]
8,725
2,694
5,354
16,773
DAUB-R [ 28 ]
7,500
2,000
4,277
13,777
TABLE I: Summary of datasets used in our experiments. Train, Val, and Test denote the numbers of training, validation, and test samples, respectively; – indicates that no separate validation split is used.
Motion Representation
mAP 50 ↑
P ↑
R ↑
F1 ↑
Zero representation
87.55
85.83
78.32
81.90
Two-frame Difference [ 34 ]
93.94
90.59
86.54
88.52
Three-frame Difference [ 35 ]
90.11
86.12
81.45
83.72
Farnebäck [ 36 ]
94.07
94.57
85.32
89.71
MNWTH [ 38 ]
88.59
92.97
77.47
84.52
MOG2 [ 39 , 40 ]
84.36
83.84
74.79
79.06
TABLE II: Detection-oriented comparison of representative motion representations on DAUB-R under a fixed detector. Only the motion representation is changed, and all variants are reported with the common mAP 50 /P/R/F1 convention. Full RIMCA is the Stage I representation used by the complete MI-DETR model; its DAUB-R detector metrics are therefore identical to the MI-DETR entry in Table III .
Method
Temporal Context
Venue
DAUB-R
ITSDT-15K
IRDST-H
mAP 50
P
R
F1
mAP 50
P
R
F1
mAP 50
P
R
F1
Single-frame methods
SANet [ 48 ]
1
ICASSP 2023
83.64
91.62
92.26
91.94
62.17
87.78
71.23
78.64
33.02
51.86
64.50
57.49
AGPCNet [ 49 ]
1
IEEE TAES 2023
81.25
84.44
97.66
90.57
67.27
91.19
74.77
82.16
29.24
46.64
63.68
53.84
RDIAN [ 44 ]
1
IEEE TGRS 2023
82.55
87.65
95.23
91.28
68.49
90.56
76.06
82.68
30.57
42.18
73.50
53.60
DNANet [ 4 ]
1
IEEE TIP 2023
83.65
88.74
95.18
91.85
70.46
88.55
80.73
84.46
31.07
51.09
61.09
55.64
TABLE III: Comparison with representative methods on three moving infrared small-target benchmarks. Best and second-best results are shown in bold and underlined , respectively. Numeric temporal-context entries denote the number of input frames for single-frame and fixed-window methods; MI-DETR instead maintains a causal recurrent state whose historical contributions decay exponentially rather than being truncated to a fixed input window.
Fig. 4: Qualitative comparison on ITSDT-15K (confidence: 0.5, NMS: 0.3). Green boxes denote ground truth annotations, blue boxes indicate MI-DETR predictions, and red boxes show results from five multi-frame baselines (iMoPKL [ 28 ] , SSTNet [ 14 ] , STME [ 27 ] , Tridos [ 26 ] , TMP [ 16 ] ).
Fig. 5: Precision–Recall (PR) curves of MI-DETR and 11 representative methods on (a) ITSDT-15K , (b) DAUB-R , and (c) IRDST-H .
Method
T
mAP 50
P
R
F1
Par.
G
FPS
Single-frame methods
SIRST5K [ 50 ]
1
24.22
44.92
54.02
49.05
11.48
182.61
6.17
DNANet [ 4 ]
1
31.07
51.09
61.09
55.64
7.22
135.24
7.21
SCTransNet [ 53 ]
1
27.41
48.34
57.63
52.58
13.71
101.61
10.34
RPCANet [ 54 ]
1
29.17
45.17
65.18
53.36
3.21
382.69
14.81
MSHNet [ 51 ]
1
27.02
45.25
60.04
51.61
6.59
69.49
16.37
TABLE IV: Accuracy–complexity comparison on IRDST-H under the unified RTX 3090 protocol. T denotes temporal context: numeric entries are the numbers of input frames, while State denotes a recurrent-state method. Par. denotes millions of parameters, G denotes GFLOPs, and FPS denotes frames per second. MI-DETR FPS is measured for the complete RIMCA + detector pipeline.
ID
Readout
mAP 50
P
R
F1
Latency (ms)
FPS
R0
Zero representation
87.55
85.83
78.32
81.90
0.000
56.36
R1
Adapted response Pt
90.25
95.62
77.08
85.35
0.150
55.88
R2
Suppressed Ht
86.97
87.99
78.27
82.84
0.233
55.63
R3
Contrast Ct
87.92
80.02
80.90
80.45
0.312
55.38
R4
Recurrent state At
95.17
94.14
90.93
92.50
0.442
54.99
R5
Filtered response Gt
86.65
85.19
78.07
81.48
0.765
54.03
TABLE V: Intermediate RIMCA readout ablation on DAUB-R. R7 is the full RIMCA output. Latency is the cumulative RIMCA processing time per frame in milliseconds; profile FPS is measured on an A100 (40 GB). These two columns are separate from the unified RTX 3090 end-to-end result.
Fig. 6: One-factor-at-a-time sensitivity analysis of the main RIMCA configuration on DAUB-R. Panels (a)–(f) vary temporal retention α , temporal-response scale β , activation threshold θm , readout weight ηm , center–surround support km , and inhibition-kernel Gaussian width σG , respectively. The star marks the main-model configuration (98.00% mAP 50 and 94.35% F1); all remaining RIMCA and detector settings are fixed.
Parameter
Tested Values
Default
α
{0.50, 0.65, 0.80, 0.90, 0.95}
0.80
β
{0.60, 0.90, 1.20, 1.50, 1.80}
1.20
θm
{0.15, 0.225, 0.30, 0.375, 0.45}
0.30
ηm
{0.30, 0.50, 0.70, 0.85, 0.95}
0.70
km
{3, 5, 7}
5
σG (inhibition width)
{0.50, 1.00, 1.50}
1.00
TABLE VI: RIMCA parameters used in the one-parameter-at-a-time sensitivity analysis. The default column is the main-model configuration.
Variant
mAP 50
P
R
F1
G
Par.
Single-pathway baselines
(1) Appearance-only
90.20
87.50
81.70
84.50
57.20
19.88
(2) Motion-only
90.00
90.30
83.40
86.71
57.20
19.88
Non-interactive aggregation
(3) Element-wise Add
96.80
93.20
93.10
93.15
91.90
31.31
(4) Direct Concat
96.40
90.30
94.70
92.45
92.70
31.38
TABLE VII: Motion–appearance interaction ablation on DAUB-R. All variants use the same RT-DETR decoder, and variants with a motion pathway use the same RIMCA representations. LGAG denotes Large-kernel Grouped Attention Gate [ 57 ] . G denotes GFLOPs and Par. denotes millions of parameters.
Detector
Var.
mAP 50
P
R
F1
G
Par.
YOLOv8 [ 58 ]
App.
83.60
91.10
71.90
80.40
6.80
2.68
Mot.
86.90
84.70
78.90
81.70
6.80
2.68
+PMI
95.80
95.40
93.00
94.20
10.50
4.32
YOLOv10 [ 59 ]
App.
82.20
86.50
71.60
78.30
8.20
2.69
Mot.
80.90
80.90
71.80
76.10
8.20
2.69
+PMI
94.10
90.80
90.50
90.60
11.70
4.01
TABLE VIII: Cross-backbone evaluation of the dual-pathway RIMCA+PMI configuration on DAUB-R. Var. denotes the evaluated variant; App. and Mot. denote appearance-only and motion-only variants. R18 denotes ResNet-18. G denotes GFLOPs and Par. denotes millions of parameters. The +PMI rows include both the motion pathway and PMI; isolated PMI attribution is given in Table VII .