RuntimeError: Sizes of tensors must match except in dimension 1. Expected size 22 but got size 21 for tensor number 1 in the list.

[Ellohiye]

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Question

When using yolov8-p6 to train 1000*2048 size images, bs=6, imgsz=1280, the training is normal. Why is the test error when imgsz=1280, bs=1?

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No response

[UltralyticsAssistant]

👋 Hello @Ellohiye, thank you for your interest in Ultralytics 🚀! We recommend a visit to the Docs for new users where you can find many Python and CLI usage examples and where many of the most common questions may already be answered.

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[Y-T-G]

You Can you elaborate on your issue?

What you did and what the issue is?

[Ellohiye]

[Ellohiye]

On this 1000*2048 size dataset, I used bs=4/6, imgsz=1280 parameters for training. The training process went well. When executing python val.py, the parameters were: imgsz=1280, bs=1, and the program reported an error as shown above

[Y-T-G]

It's a very old version of Ultralytics. You should update to the latest.

[Ellohiye]

Since we are using the yolov8 version as the baseline model, if we update it, it may lead to unfair experiments. Is there any other solution? After searching, it seems that the problem is due to the fact that the size of the dataset images is 1000*2048, which cannot be divided by 32 evenly.

[Y-T-G]

Bugs related to an old version wouldn't be counted as bugs. Since it may be fixed in the latest version. The version you're using is 15 months old.