ultralytics/docs/reference/utils/callbacks/base.md

description	keywords
Explore how to use the on-train, on-validation, on-pretrain, and on-predict callbacks in Ultralytics. Learn to update params, save models, and add integration callbacks.	Ultralytics, Callbacks, On-train, On-validation, On-pretrain, On-predict, Parameters update, Model saving, Integration callbacks

on_pretrain_routine_start

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::: ultralytics.utils.callbacks.base.on_pretrain_routine_start

on_pretrain_routine_end

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::: ultralytics.utils.callbacks.base.on_pretrain_routine_end

on_train_start

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::: ultralytics.utils.callbacks.base.on_train_start

on_train_epoch_start

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::: ultralytics.utils.callbacks.base.on_train_epoch_start

on_train_batch_start

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::: ultralytics.utils.callbacks.base.on_train_batch_start

optimizer_step

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::: ultralytics.utils.callbacks.base.optimizer_step

on_before_zero_grad

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::: ultralytics.utils.callbacks.base.on_before_zero_grad

on_train_batch_end

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::: ultralytics.utils.callbacks.base.on_train_batch_end

on_train_epoch_end

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::: ultralytics.utils.callbacks.base.on_train_epoch_end

on_fit_epoch_end

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::: ultralytics.utils.callbacks.base.on_fit_epoch_end

on_model_save

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::: ultralytics.utils.callbacks.base.on_model_save

on_train_end

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::: ultralytics.utils.callbacks.base.on_train_end

on_params_update

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::: ultralytics.utils.callbacks.base.on_params_update

teardown

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::: ultralytics.utils.callbacks.base.teardown

on_val_start

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::: ultralytics.utils.callbacks.base.on_val_start

on_val_batch_start

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::: ultralytics.utils.callbacks.base.on_val_batch_start

on_val_batch_end

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::: ultralytics.utils.callbacks.base.on_val_batch_end

on_val_end

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::: ultralytics.utils.callbacks.base.on_val_end

on_predict_start

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::: ultralytics.utils.callbacks.base.on_predict_start

on_predict_batch_start

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::: ultralytics.utils.callbacks.base.on_predict_batch_start

on_predict_batch_end

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::: ultralytics.utils.callbacks.base.on_predict_batch_end

on_predict_postprocess_end

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::: ultralytics.utils.callbacks.base.on_predict_postprocess_end

on_predict_end

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::: ultralytics.utils.callbacks.base.on_predict_end

on_export_start

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::: ultralytics.utils.callbacks.base.on_export_start

on_export_end

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::: ultralytics.utils.callbacks.base.on_export_end

get_default_callbacks

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::: ultralytics.utils.callbacks.base.get_default_callbacks

add_integration_callbacks

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::: ultralytics.utils.callbacks.base.add_integration_callbacks