File size: 42,037 Bytes
43142c4
4c401bf
 
 
 
 
 
 
 
 
43142c4
4c401bf
43142c4
4c401bf
43142c4
 
 
4c401bf
 
 
2dc1957
5519f2a
2dc1957
4c401bf
5519f2a
4c401bf
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
4c401bf
 
 
 
 
 
 
 
 
 
 
 
 
2dc1957
 
 
 
 
 
 
 
 
 
 
4c401bf
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
 
 
 
 
 
 
 
 
 
 
 
 
 
4c401bf
 
 
5519f2a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
4c401bf
 
 
 
 
 
5519f2a
2dc1957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2dc1957
 
 
 
 
 
 
 
 
 
 
 
5519f2a
2dc1957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
2dc1957
5519f2a
2dc1957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2dc1957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
 
2dc1957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
2dc1957
 
5519f2a
 
 
 
 
2dc1957
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
5519f2a
2dc1957
5519f2a
2dc1957
5519f2a
2dc1957
4c401bf
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
---
datasets:
- imagenet-1k
language: en
library_name: timm
license: apache-2.0
metrics:
- accuracy
model_name: recnext_a1
pipeline_tag: image-classification
tags:
- vision
- image-classification
- pytorch
- timm
- transformers
---

# Model Card for RecNeXt-A1

## Abstract
Recent advances in vision transformers (ViTs) have demonstrated the advantage of global modeling capabilities, prompting widespread integration of large-kernel convolutions for enlarging the effective receptive field (ERF). However, the quadratic scaling of parameter count and computational complexity (FLOPs) with respect to kernel size poses significant efficiency and optimization challenges. This paper introduces RecConv, a recursive decomposition strategy that efficiently constructs multi-frequency representations using small-kernel convolutions. RecConv establishes a linear relationship between parameter growth and decomposing levels which determines the effective receptive field $k\times 2^\ell$ for a base kernel $k$ and $\ell$ levels of decomposition, while maintaining constant FLOPs regardless of the ERF expansion. Specifically, RecConv achieves a parameter expansion of only $\ell+2$ times and a maximum FLOPs increase of $5/3$ times, compared to the exponential growth ($4^\ell$) of standard and depthwise convolutions. RecNeXt-M3 outperforms RepViT-M1.1 by 1.9 $AP^{box}$ on COCO with similar FLOPs. This innovation provides a promising avenue towards designing efficient and compact networks across various modalities. Codes and models can be found at https://github.com/suous/RecNeXt.

[![license](https://img.shields.io/github/license/suous/RecNeXt)](https://github.com/suous/RecNeXt/blob/main/LICENSE)
[![arXiv](https://img.shields.io/badge/arXiv-2412.19628-red)](https://arxiv.org/abs/2412.19628)

<div style="display: flex; justify-content: space-between;">
    <img src="https://raw.githubusercontent.com/suous/RecNeXt/refs/heads/main/figures/RecConvA.png" alt="RecConvA" style="width: 52%;">
    <img src="https://raw.githubusercontent.com/suous/RecNeXt/refs/heads/main/figures/code.png" alt="code" style="width: 46%;">
</div>

## Model Details

- **Model Type**: Image Classification / Feature Extraction
- **Model Series**: A
- **Model Stats**: 
    - **Parameters**: 5.9M
    - **MACs**: 0.9G
    - **Latency**: 1.9ms (iPhone 13, iOS 18)
    - **Throughput**: 2730 (RTX 3090)
    - **Image Size**: 224x224

- **Architecture Configuration**: 
    - **Embedding Dimensions**: (48, 96, 192, 384)
    - **Depths**: (3, 3, 15, 2)
    - **MLP Ratio**: (2, 2, 2, 2)

- **Paper**: [RecConv: Efficient Recursive Convolutions for Multi-Frequency Representations](https://arxiv.org/abs/2412.19628)

- **Code**: https://github.com/suous/RecNeXt

- **Dataset**: ImageNet-1K

## Recent Updates

**UPDATES** πŸ”₯
- **2025/07/23**: Added a simple architecture, the overall design follows [LSNet](https://github.com/jameslahm/lsnet).
- **2025/07/04**: Uploaded classification models to [HuggingFace](https://huggingface.co/suous)πŸ€—.
- **2025/07/01**: Added more comparisons with [LSNet](https://github.com/jameslahm/lsnet).
- **2025/06/27**: Added **A** series code and logs, replacing convolution with linear attention.
- **2025/03/19**: Added more ablation study results, including using attention with RecConv design.
- **2025/01/02**: Uploaded checkpoints and training logs of RecNeXt-M0.
- **2024/12/29**: Uploaded checkpoints and training logs of RecNeXt-M1 - M5.

## Model Usage

### Image Classification

```python
from urllib.request import urlopen
from PIL import Image
import timm
import torch

img = Image.open(urlopen(
    'https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/beignets-task-guide.png'
))

model = timm.create_model('recnext_a1', pretrained=True, distillation=False)
model = model.eval()

# get model specific transforms (normalization, resize)
data_config = timm.data.resolve_model_data_config(model)
transforms = timm.data.create_transform(**data_config, is_training=False)

output = model(transforms(img).unsqueeze(0))  # unsqueeze single image into batch of 1

top5_probabilities, top5_class_indices = torch.topk(output.softmax(dim=1) * 100, k=5)
```

### Converting to Inference Mode

```python
import utils

# Convert training-time model to inference structure, fuse batchnorms
utils.replace_batchnorm(model)
```
## Model Comparison

### Classification

We introduce two series of models: the **A** series uses linear attention and nearest interpolation, while the **M** series employs convolution and bilinear interpolation for simplicity and broader hardware compatibility (e.g., to address suboptimal nearest interpolation support in some iOS versions). 

> **dist**: distillation; **base**: without distillation (all models are trained over 300 epochs).

| model | top_1_accuracy | params | gmacs | npu_latency | cpu_latency | throughput | fused_weights                                                                                                                                                                                                | training_logs                                                                                                                                                                                                         |
|-------|----------------|--------|-------|-------------|-------------|------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| M0    | 74.7* \| 73.2  | 2.5M   | 0.4   | 1.0ms       | 189ms       | 750        | [dist](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m0_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m0_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_m0_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_m0_without_distill_300e.txt) |
| M1    | 79.2* \| 78.0  | 5.2M   | 0.9   | 1.4ms       | 361ms       | 384        | [dist](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m1_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m1_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_m1_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_m1_without_distill_300e.txt) |
| M2    | 80.3* \| 79.2  | 6.8M   | 1.2   | 1.5ms       | 431ms       | 325        | [dist](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m2_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m2_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_m2_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_m2_without_distill_300e.txt) |
| M3    | 80.9* \| 79.6  | 8.2M   | 1.4   | 1.6ms       | 482ms       | 314        | [dist](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m3_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m3_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_m3_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_m3_without_distill_300e.txt) |
| M4    | 82.5* \| 81.4  | 14.1M  | 2.4   | 2.4ms       | 843ms       | 169        | [dist](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m4_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m4_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_m4_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_m4_without_distill_300e.txt) |
| M5    | 83.3* \| 82.9  | 22.9M  | 4.7   | 3.4ms       | 1487ms      | 104        | [dist](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m5_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m5_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_m5_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_m5_without_distill_300e.txt) |
| A0    | 75.0* \| 73.6  | 2.8M   | 0.4   | 1.4ms       | 177ms       | 4891       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a0_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a0_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_a0_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_a0_without_distill_300e.txt) |
| A1    | 79.6* \| 78.3  | 5.9M   | 0.9   | 1.9ms       | 334ms       | 2730       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a1_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a1_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_a1_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_a1_without_distill_300e.txt) |
| A2    | 80.8* \| 79.6  | 7.9M   | 1.2   | 2.2ms       | 413ms       | 2331       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a2_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a2_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_a2_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_a2_without_distill_300e.txt) |
| A3    | 81.1* \| 80.1  | 9.0M   | 1.4   | 2.4ms       | 447ms       | 2151       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a3_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a3_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_a3_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_a3_without_distill_300e.txt) |
| A4    | 82.5* \| 81.6  | 15.8M  | 2.4   | 3.6ms       | 764ms       | 1265       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a4_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a4_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_a4_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_a4_without_distill_300e.txt) |
| A5    | 83.5* \| 83.1  | 25.7M  | 4.7   | 5.6ms       | 1376ms      | 733        | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a5_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a5_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/distill/recnext_a5_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/logs/normal/recnext_a5_without_distill_300e.txt) |

### Comparison with [LSNet](https://github.com/jameslahm/lsnet)

We present a simple architecture, the overall design follows [LSNet](https://github.com/jameslahm/lsnet). This framework centers around sharing channel features from the previous layers.
Our motivation for doing so is to reduce the computational cost of token mixers and minimize feature redundancy in the final stage.

![Architecture](https://raw.githubusercontent.com/suous/RecNeXt/refs/heads/main/lsnet/figures/architecture.png)

#### With **Shared-Channel Blocks**

| model | top_1_accuracy | params | gmacs | npu_latency | cpu_latency | throughput | fused_weights                                                                                                                                                                                                                          | training_logs                                                                                                                                                                                                                                               |
|-------|----------------|--------|-------|-------------|-------------|------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| T     | 76.8 \| 75.2   | 12.1M  | 0.3   | 1.8ms       | 105ms       | 13957      | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_t_share_channel_distill_300e_fused.pt) \| [norm](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_t_share_channel_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/distill/recnext_t_share_channel_distill_300e.txt) \| [norm](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/normal/recnext_t_share_channel_without_distill_300e.txt) |
| S     | 79.5 \| 78.3   | 15.8M  | 0.7   | 2.0ms       | 182ms       | 8034       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_s_share_channel_distill_300e_fused.pt) \| [norm](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_s_share_channel_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/distill/recnext_s_share_channel_distill_300e.txt) \| [norm](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/normal/recnext_s_share_channel_without_distill_300e.txt) |
| B     | 81.5 \| 80.3   | 19.2M  | 1.1   | 2.5ms       | 296ms       | 4472       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_b_share_channel_distill_300e_fused.pt) \| [norm](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_b_share_channel_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/distill/recnext_b_share_channel_distill_300e.txt) \| [norm](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/normal/recnext_b_share_channel_without_distill_300e.txt) |

#### Without **Shared-Channel Blocks**

| model | top_1_accuracy | params | gmacs | npu_latency | cpu_latency | throughput | fused_weights                                                                                                                                                                                              | training_logs                                                                                                                                                                                                                   |
|-------|----------------|--------|-------|-------------|-------------|------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| T     | 76.6* \| 75.1  | 12.1M  | 0.3   | 1.8ms       | 109ms       | 13878      | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_t_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_t_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/distill/recnext_t_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/normal/recnext_t_without_distill_300e.txt) |
| S     | 79.6* \| 78.3  | 15.8M  | 0.7   | 2.0ms       | 188ms       | 7989       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_s_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_s_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/distill/recnext_s_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/normal/recnext_s_without_distill_300e.txt) |
| B     | 81.4* \| 80.3  | 19.3M  | 1.1   | 2.5ms       | 290ms       | 4450       | [dist](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_b_distill_300e_fused.pt) \| [base](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_b_without_distill_300e_fused.pt) | [dist](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/distill/recnext_b_distill_300e.txt) \| [base](https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/logs/normal/recnext_b_without_distill_300e.txt) |

> The NPU latency is measured on an iPhone 13 with models compiled by Core ML Tools.
> The CPU latency is accessed on a Quad-core ARM Cortex-A57 processor in ONNX format.
> And the throughput is tested on an Nvidia RTX3090 with maximum power-of-two batch size that fits in memory.


## Latency Measurement

The latency reported in RecNeXt for iPhone 13 (iOS 18) uses the benchmark tool from [XCode 14](https://developer.apple.com/videos/play/wwdc2022/10027/).

<details>
<summary>
RecNeXt-M0
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_m0_224x224.png" alt="recnext_m0">
</details>

<details>
<summary>
RecNeXt-M1
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_m1_224x224.png" alt="recnext_m1">
</details>

<details>
<summary>
RecNeXt-M2
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_m2_224x224.png" alt="recnext_m2">
</details>

<details>
<summary>
RecNeXt-M3
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_m3_224x224.png" alt="recnext_m3">
</details>

<details>
<summary>
RecNeXt-M4
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_m4_224x224.png" alt="recnext_m4">
</details>

<details>
<summary>
RecNeXt-M5
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_m5_224x224.png" alt="recnext_m5">
</details>

<details>
<summary>
RecNeXt-A0
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_a0_224x224.png" alt="recnext_a0">
</details>

<details>
<summary>
RecNeXt-A1
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_a1_224x224.png" alt="recnext_a1">
</details>

<details>
<summary>
RecNeXt-A2
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_a2_224x224.png" alt="recnext_a2">
</details>

<details>
<summary>
RecNeXt-A3
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_a3_224x224.png" alt="recnext_a3">
</details>

<details>
<summary>
RecNeXt-A4
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_a4_224x224.png" alt="recnext_a4">
</details>

<details>
<summary>
RecNeXt-A5
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/latency/recnext_a5_224x224.png" alt="recnext_a5">
</details>

<details>
<summary>
RecNeXt-T
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/figures/latency/recnext_t_224x224.png" alt="recnext_t">
</details>

<details>
<summary>
RecNeXt-S
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/figures/latency/recnext_s_224x224.png" alt="recnext_s">
</details>

<details>
<summary>
RecNeXt-B
</summary>
<img src="https://raw.githubusercontent.com/suous/RecNeXt/main/lsnet/figures/latency/recnext_b_224x224.png" alt="recnext_b">
</details>

Tips: export the model to Core ML model
```
python export_coreml.py --model recnext_m1 --ckpt pretrain/recnext_m1_distill_300e.pth
```
Tips: measure the throughput on GPU
```
python speed_gpu.py --model recnext_m1
```

## ImageNet (Training and Evaluation)

### Prerequisites
`conda` virtual environment is recommended.
```
conda create -n recnext python=3.8
pip install -r requirements.txt
```

### Data preparation

Download and extract ImageNet train and val images from http://image-net.org/. The training and validation data are expected to be in the `train` folder and `val` folder respectively:

```bash
# script to extract ImageNet dataset: https://github.com/pytorch/examples/blob/main/imagenet/extract_ILSVRC.sh
# ILSVRC2012_img_train.tar (about 138 GB)
# ILSVRC2012_img_val.tar (about 6.3 GB)
```

```
# organize the ImageNet dataset as follows:
imagenet
β”œβ”€β”€ train
β”‚   β”œβ”€β”€ n01440764
β”‚   β”‚   β”œβ”€β”€ n01440764_10026.JPEG
β”‚   β”‚   β”œβ”€β”€ n01440764_10027.JPEG
β”‚   β”‚   β”œβ”€β”€ ......
β”‚   β”œβ”€β”€ ......
β”œβ”€β”€ val
β”‚   β”œβ”€β”€ n01440764
β”‚   β”‚   β”œβ”€β”€ ILSVRC2012_val_00000293.JPEG
β”‚   β”‚   β”œβ”€β”€ ILSVRC2012_val_00002138.JPEG
β”‚   β”‚   β”œβ”€β”€ ......
β”‚   β”œβ”€β”€ ......
```

### Training
To train RecNeXt-M1 on an 8-GPU machine:

```
python -m torch.distributed.launch --nproc_per_node=8 --master_port 12346 --use_env main.py --model recnext_m1 --data-path ~/imagenet --dist-eval
```
Tips: specify your data path and model name!

### Testing
For example, to test RecNeXt-M1:
```
python main.py --eval --model recnext_m1 --resume pretrain/recnext_m1_distill_300e.pth --data-path ~/imagenet
```

Use pretrained model without knowledge distillation from [HuggingFace](https://huggingface.co/suous) πŸ€—.
```bash
python main.py --eval --model recnext_m1 --data-path ~/imagenet --pretrained --distillation-type none
```

Use pretrained model with knowledge distillation from [HuggingFace](https://huggingface.co/suous) πŸ€—.
```bash
python main.py --eval --model recnext_m1 --data-path ~/imagenet --pretrained --distillation-type hard
```

### Fused model evaluation
For example, to evaluate RecNeXt-M1 with the fused model: [![Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/suous/RecNeXt/blob/main/demo/fused_model_evaluation.ipynb)
```
python fuse_eval.py --model recnext_m1 --resume pretrain/recnext_m1_distill_300e_fused.pt --data-path ~/imagenet
```

### Extract model for publishing

```
# without distillation
python publish.py --model_name recnext_m1 --checkpoint_path pretrain/checkpoint_best.pth --epochs 300

# with distillation
python publish.py --model_name recnext_m1 --checkpoint_path pretrain/checkpoint_best.pth --epochs 300 --distillation

# fused model
python publish.py --model_name recnext_m1 --checkpoint_path pretrain/checkpoint_best.pth --epochs 300 --fused
```

## Downstream Tasks
[Object Detection and Instance Segmentation](https://github.com/suous/RecNeXt/blob/main/detection/README.md)<br>

| model | $AP^b$ | $AP_{50}^b$ | $AP_{75}^b$ | $AP^m$ | $AP_{50}^m$ | $AP_{75}^m$ | Latency |                                       Ckpt                                        |                                              Log                                               |
|:------|:------:|:-----------:|:-----------:|:------:|:-----------:|:-----------:|:-------:|:---------------------------------------------------------------------------------:|:----------------------------------------------------------------------------------------------:|
| M3    |  41.7  |    63.4     |    45.4     |  38.6  |    60.5     |    41.4     |  5.2ms  | [M3](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m3_coco.pth) | [M3](https://raw.githubusercontent.com/suous/RecNeXt/main/detection/logs/recnext_m3_coco.json) |
| M4    |  43.5  |    64.9     |    47.7     |  39.7  |    62.1     |    42.4     |  7.6ms  | [M4](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m4_coco.pth) | [M4](https://raw.githubusercontent.com/suous/RecNeXt/main/detection/logs/recnext_m4_coco.json) |
| M5    |  44.6  |    66.3     |    49.0     |  40.6  |    63.5     |    43.5     | 12.4ms  | [M5](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m5_coco.pth) | [M5](https://raw.githubusercontent.com/suous/RecNeXt/main/detection/logs/recnext_m5_coco.json) |
| A3    |  42.1  |    64.1     |    46.2     |  38.8  |    61.1     |    41.6     |  8.3ms  | [A3](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a3_coco.pth) | [A3](https://raw.githubusercontent.com/suous/RecNeXt/main/detection/logs/recnext_a3_coco.json) |
| A4    |  43.5  |    65.4     |    47.6     |  39.8  |    62.4     |    42.9     | 14.0ms  | [A4](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a4_coco.pth) | [A4](https://raw.githubusercontent.com/suous/RecNeXt/main/detection/logs/recnext_a4_coco.json) |
| A5    |  44.4  |    66.3     |    48.9     |  40.3  |    63.3     |    43.4     | 25.3ms  | [A5](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a5_coco.pth) | [A5](https://raw.githubusercontent.com/suous/RecNeXt/main/detection/logs/recnext_a5_coco.json) |

[Semantic Segmentation](https://github.com/suous/RecNeXt/blob/main/segmentation/README.md)

| Model      | mIoU | Latency |                                        Ckpt                                         |                                                 Log                                                 |
|:-----------|:----:|:-------:|:-----------------------------------------------------------------------------------:|:---------------------------------------------------------------------------------------------------:|
| RecNeXt-M3 | 41.0 |  5.6ms  | [M3](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m3_ade20k.pth) | [M3](https://raw.githubusercontent.com/suous/RecNeXt/main/segmentation/logs/recnext_m3_ade20k.json) |
| RecNeXt-M4 | 43.6 |  7.2ms  | [M4](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m4_ade20k.pth) | [M4](https://raw.githubusercontent.com/suous/RecNeXt/main/segmentation/logs/recnext_m4_ade20k.json) |
| RecNeXt-M5 | 46.0 | 12.4ms  | [M5](https://github.com/suous/RecNeXt/releases/download/v1.0/recnext_m5_ade20k.pth) | [M5](https://raw.githubusercontent.com/suous/RecNeXt/main/segmentation/logs/recnext_m5_ade20k.json) |
| RecNeXt-A3 | 41.9 |  8.4ms  | [A3](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a3_ade20k.pth) | [A3](https://raw.githubusercontent.com/suous/RecNeXt/main/segmentation/logs/recnext_a3_ade20k.json) |
| RecNeXt-A4 | 43.0 | 14.0ms  | [A4](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a4_ade20k.pth) | [A4](https://raw.githubusercontent.com/suous/RecNeXt/main/segmentation/logs/recnext_a4_ade20k.json) |
| RecNeXt-A5 | 46.5 | 25.3ms  | [A5](https://github.com/suous/RecNeXt/releases/download/v2.0/recnext_a5_ade20k.pth) | [A5](https://raw.githubusercontent.com/suous/RecNeXt/main/segmentation/logs/recnext_a5_ade20k.json) |

## Ablation Study

### Overall Experiments

![ablation](https://raw.githubusercontent.com/suous/RecNeXt/main/figures/ablation.png)

<details>
  <summary>
  <span style="font-size: larger; ">Ablation Logs</span>
  </summary>

<pre>
logs/ablation
β”œβ”€β”€ 224
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_3x3_7464.txt">recnext_m1_120e_224x224_3x3_7464.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_7x7_7552.txt">recnext_m1_120e_224x224_7x7_7552.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_bxb_7541.txt">recnext_m1_120e_224x224_bxb_7541.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_rec_3x3_7548.txt">recnext_m1_120e_224x224_rec_3x3_7548.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_rec_5x5_7603.txt">recnext_m1_120e_224x224_rec_5x5_7603.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_rec_7x7_7567.txt">recnext_m1_120e_224x224_rec_7x7_7567.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_rec_7x7_nearest_7571.txt">recnext_m1_120e_224x224_rec_7x7_nearest_7571.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_rec_7x7_nearest_ssm_7593.txt">recnext_m1_120e_224x224_rec_7x7_nearest_ssm_7593.txt</a>
β”‚   └── <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/224/recnext_m1_120e_224x224_rec_7x7_unpool_7548.txt">recnext_m1_120e_224x224_rec_7x7_unpool_7548.txt</a>
└── 384
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_3x3_7635.txt">recnext_m1_120e_384x384_3x3_7635.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_7x7_7742.txt">recnext_m1_120e_384x384_7x7_7742.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_bxb_7800.txt">recnext_m1_120e_384x384_bxb_7800.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_3x3_7772.txt">recnext_m1_120e_384x384_rec_3x3_7772.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_5x5_7811.txt">recnext_m1_120e_384x384_rec_5x5_7811.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_7x7_7803.txt">recnext_m1_120e_384x384_rec_7x7_7803.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_convtrans_3x3_basic_7726.txt">recnext_m1_120e_384x384_rec_convtrans_3x3_basic_7726.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_convtrans_5x5_basic_7787.txt">recnext_m1_120e_384x384_rec_convtrans_5x5_basic_7787.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_convtrans_7x7_basic_7824.txt">recnext_m1_120e_384x384_rec_convtrans_7x7_basic_7824.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_convtrans_7x7_group_7791.txt">recnext_m1_120e_384x384_rec_convtrans_7x7_group_7791.txt</a>
    └── <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/logs/ablation/384/recnext_m1_120e_384x384_rec_convtrans_7x7_split_7683.txt">recnext_m1_120e_384x384_rec_convtrans_7x7_split_7683.txt</a>
</pre>
</details>

<details>
  <summary>
  <span style="font-size: larger; ">RecConv Recurrent Aggregation</span>
  </summary>

  ```python
class RecConv2d(nn.Module):
    def __init__(self, in_channels, kernel_size=5, bias=False, level=1, mode='nearest'):
        super().__init__()
        self.level = level
        self.mode = mode
        kwargs = {
            'in_channels': in_channels,
            'out_channels': in_channels,
            'groups': in_channels,
            'kernel_size': kernel_size,
            'padding': kernel_size // 2,
            'bias': bias
        }
        self.n = nn.Conv2d(stride=2, **kwargs)
        self.a = nn.Conv2d(**kwargs) if level >1 else None
        self.b = nn.Conv2d(**kwargs) 
        self.c = nn.Conv2d(**kwargs)
        self.d = nn.Conv2d(**kwargs)

    def forward(self, x):
        # 1. Generate Multi-scale Features.
        fs = [x]
        for _ in range(self.level):
            fs.append(self.n(fs[-1]))

        # 2. Multi-scale Recurrent Aggregation.
        h = None
        for i, o in reversed(list(zip(fs[1:], fs[:-1]))):
            h = self.a(h) + self.b(i) if h is not None else self.b(i)
            h = nn.functional.interpolate(h, size=o.shape[2:], mode=self.mode)
        return self.c(h) + self.d(x)
  ```
</details>

### RecConv Variants

<div style="display: flex; justify-content: space-between;">
    <img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/RecConvB.png" alt="RecConvB" style="width: 49%;">
    <img src="https://raw.githubusercontent.com/suous/RecNeXt/main/figures/RecConvC.png" alt="RecConvC" style="width: 49%;">
</div>


<details>
  <summary>
  <span style="font-size: larger; ">RecConv Variant Details</span>
  </summary>

- **RecConv using group convolutions**

```python
# RecConv Variant A
# recursive decomposition on both spatial and channel dimensions
# downsample and upsample through group convolutions
class RecConv2d(nn.Module):
    def __init__(self, in_channels, kernel_size=5, bias=False, level=2):
        super().__init__()
        self.level = level
        kwargs = {'kernel_size': kernel_size, 'padding': kernel_size // 2, 'bias': bias}
        downs = []
        for l in range(level):
            i_channels = in_channels // (2 ** l)
            o_channels = in_channels // (2 ** (l+1))
            downs.append(nn.Conv2d(in_channels=i_channels, out_channels=o_channels, groups=o_channels, stride=2, **kwargs))
        self.downs = nn.ModuleList(downs)

        convs = []
        for l in range(level+1):
            channels = in_channels // (2 ** l)
            convs.append(nn.Conv2d(in_channels=channels, out_channels=channels, groups=channels, **kwargs))
        self.convs = nn.ModuleList(reversed(convs))

        # this is the simplest modification, only support resoltions like 256, 384, etc
        kwargs['kernel_size'] = kernel_size + 1
        ups = []
        for l in range(level):
            i_channels = in_channels // (2 ** (l+1))
            o_channels = in_channels // (2 ** l)
            ups.append(nn.ConvTranspose2d(in_channels=i_channels, out_channels=o_channels, groups=i_channels, stride=2, **kwargs))
        self.ups = nn.ModuleList(reversed(ups))
        
    def forward(self, x):
        i = x
        features = []
        for down in self.downs:
            x, s = down(x), x.shape[2:]
            features.append((x, s))

        x = 0
        for conv, up, (f, s) in zip(self.convs, self.ups, reversed(features)):
            x = up(conv(f + x))
        return self.convs[self.level](i + x)
```

- **RecConv using channel-wise concatenation**

```python
# recursive decomposition on both spatial and channel dimensions
# downsample using channel-wise split, followed by depthwise convolution with a stride of 2
# upsample through channel-wise concatenation
class RecConv2d(nn.Module):
    def __init__(self, in_channels, kernel_size=5, bias=False, level=2):
        super().__init__()
        self.level = level
        kwargs = {'kernel_size': kernel_size, 'padding': kernel_size // 2, 'bias': bias}
        downs = []
        for l in range(level):
            channels = in_channels // (2 ** (l+1))
            downs.append(nn.Conv2d(in_channels=channels, out_channels=channels, groups=channels, stride=2, **kwargs))
        self.downs = nn.ModuleList(downs)

        convs = []
        for l in range(level+1):
            channels = in_channels // (2 ** l)
            convs.append(nn.Conv2d(in_channels=channels, out_channels=channels, groups=channels, **kwargs))
        self.convs = nn.ModuleList(reversed(convs))

 .      # this is the simplest modification, only support resoltions like 256, 384, etc
        kwargs['kernel_size'] = kernel_size + 1
        ups = []
        for l in range(level):
            channels = in_channels // (2 ** (l+1))
            ups.append(nn.ConvTranspose2d(in_channels=channels, out_channels=channels, groups=channels, stride=2, **kwargs))
        self.ups = nn.ModuleList(reversed(ups))

    def forward(self, x):
        features = []
        for down in self.downs:
            r, x = torch.chunk(x, 2, dim=1)
            x, s = down(x), x.shape[2:]
            features.append((r, s))

        for conv, up, (r, s) in zip(self.convs, self.ups, reversed(features)):
            x = torch.cat([r, up(conv(x))], dim=1)
        return self.convs[self.level](x)
```
</details>

### RecConv Beyond

We apply RecConv to [MLLA](https://github.com/LeapLabTHU/MLLA) small variants, replacing linear attention and downsampling layers.
Result in higher throughput and less training memory usage.

<details>
  <summary>
  <span style="font-size: larger; ">Ablation Logs</span>
  </summary>

<pre>
mlla/logs
β”œβ”€β”€ 1_mlla_nano
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/1_mlla_nano/01_baseline.txt">01_baseline.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/1_mlla_nano/02_recconv_5x5_conv_trans.txt">02_recconv_5x5_conv_trans.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/1_mlla_nano/03_recconv_5x5_nearest_interp.txt">03_recconv_5x5_nearest_interp.txt</a>
β”‚   β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/1_mlla_nano/04_recattn_nearest_interp.txt">04_recattn_nearest_interp.txt</a>
β”‚   └── <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/1_mlla_nano/05_recattn_nearest_interp_simplify.txt">05_recattn_nearest_interp_simplify.txt</a>
└── 2_mlla_mini
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/2_mlla_mini/01_baseline.txt">01_baseline.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/2_mlla_mini/02_recconv_5x5_conv_trans.txt">02_recconv_5x5_conv_trans.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/2_mlla_mini/03_recconv_5x5_nearest_interp.txt">03_recconv_5x5_nearest_interp.txt</a>
    β”œβ”€β”€ <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/2_mlla_mini/04_recattn_nearest_interp.txt">04_recattn_nearest_interp.txt</a>
    └── <a style="text-decoration:none" href="https://raw.githubusercontent.com/suous/RecNeXt/main/mlla/logs/2_mlla_mini/05_recattn_nearest_interp_simplify.txt">05_recattn_nearest_interp_simplify.txt</a>
</pre>
</details>

## Limitations

1. RecNeXt exhibits the lowest **throughput** among models of comparable parameter size due to extensive use of bilinear interpolation, which can be mitigated by employing transposed convolution.
2. The recursive decomposition may introduce **numerical instability** during mixed precision training, which can be alleviated by using fixed-point or BFloat16 arithmetic.
3. **Compatibility issues** with bilinear interpolation and transposed convolution on certain iOS versions may also result in performance degradation.

## Acknowledgement

Classification (ImageNet) code base is partly built with [LeViT](https://github.com/facebookresearch/LeViT), [PoolFormer](https://github.com/sail-sg/poolformer), [EfficientFormer](https://github.com/snap-research/EfficientFormer),  [RepViT](https://github.com/THU-MIG/RepViT), [LSNet](https://github.com/jameslahm/lsnet), [MLLA](https://github.com/LeapLabTHU/MLLA), and [MogaNet](https://github.com/Westlake-AI/MogaNet).

The detection and segmentation pipeline is from [MMCV](https://github.com/open-mmlab/mmcv) ([MMDetection](https://github.com/open-mmlab/mmdetection) and [MMSegmentation](https://github.com/open-mmlab/mmsegmentation)).

Thanks for the great implementations!

## Citation

```BibTeX
@misc{zhao2024recnext,
      title={RecConv: Efficient Recursive Convolutions for Multi-Frequency Representations},
      author={Mingshu Zhao and Yi Luo and Yong Ouyang},
      year={2024},
      eprint={2412.19628},
      archivePrefix={arXiv},
      primaryClass={cs.CV}
}
```