third_party/mmyolo/docs/en/common_usage/freeze_layers.md

Freeze layers

Freeze the weight of backbone

In MMYOLO, we can freeze some stages of the backbone network by setting frozen_stages parameters, so that these stage parameters do not participate in model updating. It should be noted that frozen_stages = i means that all parameters from the initial stage to the i^th stage will be frozen. The following is an example of YOLOv5. Other algorithms are the same logic.

_base_ = './yolov5_s-v61_syncbn_8xb16-300e_coco.py'

model = dict(
    backbone=dict(
        frozen_stages=1 # Indicates that the parameters in the first stage and all stages before it are frozen
    ))

Freeze the weight of neck

In addition, it's able to freeze the whole neck with the parameter freeze_all in MMYOLO. The following is an example of YOLOv5. Other algorithms are the same logic.

_base_ = './yolov5_s-v61_syncbn_8xb16-300e_coco.py'

model = dict(
    neck=dict(
        freeze_all=True # If freeze_all=True, all parameters of the neck will be frozen
    ))