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Only use GitHub issues for issues with the implementation, not for issues with specific datasets or general questions about functionality.
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Thank you!

1. Check that you are up-to-date with the master branch of keras-retinanet.
2. Check that you are up-to-date with the latest version of Keras: https://github.com/keras-team/keras.
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   The installation instructions can be found here: https://www.tensorflow.org/get_started/os_setup.
4. Check that you have read the entire README.md: https://github.com/fizyr/keras-retinanet/README.md.
   Most noticably the FAQ section shows common issues: https://github.com/fizyr/keras-retinanet#faq.
5. Clearly describe the issues you're having including the expected behaviour, the actual behaviour
   and the steps required to trigger the issue.
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I have debug my training samples by myself. When train the model using my own datasets, the issue is as below:

The bboxes are within the image. I do not know why it shows Image contains the following invalid boxes.
The bboxes are reasonable. Could you please give a explanation?