Hello and thank you for this help forum. I try to train a yolov11 model with a certain subset of classes from the CityScapes dataset . As my results so far are only moderate, I would like to try another approach and use a weighted data loader in order to have balanced classes during training. I tr…

@Toxite might be able to answer this more definitely, but I’d guess that it doesn’t work for multiple GPUs. You could try setting device=0 instead to see if that helps.

Thank you @BurhanQ ! I just found out that the author of the page I linked also provided some instructions for multiple GPUS ( Google Colab ). This will definitely be my next approach. Please let me know if you have any other insight!

The callbacks would still not work with multi-GPU. Neither monkey-patching, nor callbacks work with multi-GPU training. You will have to modify the source code to make the modifications stick. By adding the YOLOWeightedDataset to this file: ultralytics/data/build.py d9292fb7f #…

Thanks for your insight, @Toxite ! So, do I understand you right that the code that the auther provides in their Colab will just not work? I find it strange that they would publish a code that was not tested before. However, I also had no success testing the approach provided in the colab…

Hello, I’m a newbie who is new to YOLO. I would like to ask you about the specific process of adding the weighted data loader to yolov11. I also want to use a weighted data to solve the data imbalance problem

Hey @sparking-cloud — quickest way that works on YOLO11 and multi-GPU: Implement your weighted dataset subclass (e.g., YOLOWeightedDataset) in a separate module (keep the tutorial’s logic). Tell YOLO to use it by editing ultralytics/data/build.py so build_yolo_dataset() returns your class: #…

Balance Classes During Training - Yolov11

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speendo January 19, 2025, 1:33pm 6

Thanks! It seems that worked.

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Balance Classes During Training - Yolov11

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