The mAP value starting from 0.05% although the freeze block is set. Shouldn't it preserve the features of the base peoplenet model?

There is no update from you for a period, assuming this is not an issue anymore. Hence we are closing this topic. If need further support, please open a new one. Thanks

You can finetune peoplenet with TAO. An example can be found in TAO Toolkit Use Cases - 2. Adapting to different | NVIDIA Developer.