Slightly modify CLI execution (#3687)

* Slightly modify CLI execution

This simple change makes it easier to run the primary functions of this
repo (train/detect/test) from within Python. An object which represents
`opt` can be constructed and fed to the `main` function of each of these
modules, rather than having to call the lower level functions directly,
or run the module as a script.

* Update export.py

Add CLI parsing update for more convenient module usage within Python.

Co-authored-by: Lewis Belcher <lb@desupervised.io>

detect.py

@@ -172,7 +172,7 @@ def detect(weights='yolov5s.pt',  # model.pt path(s)
     print(f'Done. ({time.time() - t0:.3f}s)')
 
 
-if __name__ == '__main__':
+def parse_opt():
     parser = argparse.ArgumentParser()
     parser.add_argument('--weights', nargs='+', type=str, default='yolov5s.pt', help='model.pt path(s)')
     parser.add_argument('--source', type=str, default='data/images', help='file/dir/URL/glob, 0 for webcam')
@@ -198,7 +198,15 @@ if __name__ == '__main__':
     parser.add_argument('--hide-conf', default=False, action='store_true', help='hide confidences')
     parser.add_argument('--half', action='store_true', help='use FP16 half-precision inference')
     opt = parser.parse_args()
+    return opt
+
+
+def main(opt):
     print(opt)
     check_requirements(exclude=('tensorboard', 'thop'))
-
     detect(**vars(opt))
+
+
+if __name__ == "__main__":
+    opt = parse_opt()
+    main(opt)

models/export.py

@@ -144,7 +144,7 @@ def export(weights='./yolov5s.pt',  # weights path
     print(f'\nExport complete ({time.time() - t:.2f}s). Visualize with https://github.com/lutzroeder/netron.')
 
 
-if __name__ == '__main__':
+def parse_opt():
     parser = argparse.ArgumentParser()
     parser.add_argument('--weights', type=str, default='./yolov5s.pt', help='weights path')
     parser.add_argument('--img-size', nargs='+', type=int, default=[640, 640], help='image (height, width)')
@@ -159,7 +159,15 @@ if __name__ == '__main__':
     parser.add_argument('--simplify', action='store_true', help='ONNX: simplify model')
     parser.add_argument('--opset-version', type=int, default=12, help='ONNX: opset version')
     opt = parser.parse_args()
+    return opt
+
+
+def main(opt):
     print(opt)
     set_logging()
-
     export(**vars(opt))
+
+
+if __name__ == "__main__":
+    opt = parse_opt()
+    main(opt)

test.py

@@ -294,7 +294,7 @@ def test(data,
     return (mp, mr, map50, map, *(loss.cpu() / len(dataloader)).tolist()), maps, t
 
 
-if __name__ == '__main__':
+def parse_opt():
     parser = argparse.ArgumentParser(prog='test.py')
     parser.add_argument('--data', type=str, default='data/coco128.yaml', help='dataset.yaml path')
     parser.add_argument('--weights', nargs='+', type=str, default='yolov5s.pt', help='model.pt path(s)')
@@ -319,6 +319,10 @@ if __name__ == '__main__':
     opt.save_json |= opt.data.endswith('coco.yaml')
     opt.save_txt |= opt.save_hybrid
     opt.data = check_file(opt.data)  # check file
+    return opt
+
+
+def main(opt):
     print(opt)
     check_requirements(exclude=('tensorboard', 'thop'))
 
@@ -344,3 +348,8 @@ if __name__ == '__main__':
             np.savetxt(f, y, fmt='%10.4g')  # save
         os.system('zip -r study.zip study_*.txt')
         plot_study_txt(x=x)  # plot
+
+
+if __name__ == "__main__":
+    opt = parse_opt()
+    main(opt)

train.py

@@ -463,7 +463,7 @@ def train(hyp,  # path/to/hyp.yaml or hyp dictionary
     return results
 
 
-if __name__ == '__main__':
+def parse_opt():
     parser = argparse.ArgumentParser()
     parser.add_argument('--weights', type=str, default='yolov5s.pt', help='initial weights path')
     parser.add_argument('--cfg', type=str, default='', help='model.yaml path')
@@ -504,6 +504,11 @@ if __name__ == '__main__':
     # Set DDP variables
     opt.world_size = int(getattr(os.environ, 'WORLD_SIZE', 1))
     opt.global_rank = int(getattr(os.environ, 'RANK', -1))
+    return opt
+
+
+def main(opt):
+    print(opt)
     set_logging(opt.global_rank)
     if opt.global_rank in [-1, 0]:
         check_git_status()
@@ -628,3 +633,8 @@ if __name__ == '__main__':
         plot_evolution(yaml_file)
         print(f'Hyperparameter evolution complete. Best results saved as: {yaml_file}\n'
               f'Command to train a new model with these hyperparameters: $ python train.py --hyp {yaml_file}')
+
+
+if __name__ == "__main__":
+    opt = parse_opt()
+    main(opt)