_base_ = [
    'mmaction::_base_/models/mvit_small.py',
    'mmaction::_base_/default_runtime.py'
]

model = dict(
    backbone=dict(
        drop_path_rate=0.1,
        dim_mul_in_attention=False,
        pretrained=None,
        pretrained_type='maskfeat',
    ),
    data_preprocessor=dict(
        type='ActionDataPreprocessor',
        mean=[114.75, 114.75, 114.75],
        std=[57.375, 57.375, 57.375],
        blending=dict(
            type='RandomBatchAugment',
            augments=[
                dict(type='MixupBlending', alpha=0.8, num_classes=400),
                dict(type='CutmixBlending', alpha=1, num_classes=400)
            ]),
        format_shape='NCTHW'),
    cls_head=dict(dropout_ratio=0., init_scale=0.001))

# dataset settings
dataset_type = 'VideoDataset'
data_root = 'data/kinetics400/videos_train'
data_root_val = 'data/kinetics400/videos_val'
ann_file_train = 'data/kinetics400/kinetics400_train_list_videos.txt'
ann_file_val = 'data/kinetics400/kinetics400_val_list_videos.txt'
ann_file_test = 'data/kinetics400/kinetics400_val_list_videos.txt'

train_pipeline = [
    dict(type='DecordInit'),
    dict(type='SampleFrames', clip_len=16, frame_interval=4, num_clips=1),
    dict(type='DecordDecode'),
    dict(type='Resize', scale=(-1, 256)),
    dict(type='PytorchVideoWrapper', op='RandAugment', magnitude=7),
    dict(type='RandomResizedCrop'),
    dict(type='Resize', scale=(224, 224), keep_ratio=False),
    dict(type='Flip', flip_ratio=0.5),
    dict(type='RandomErasing', erase_prob=0.25, mode='rand'),
    dict(type='FormatShape', input_format='NCTHW'),
    dict(type='PackActionInputs')
]
val_pipeline = [
    dict(type='DecordInit'),
    dict(
        type='SampleFrames',
        clip_len=16,
        frame_interval=4,
        num_clips=1,
        test_mode=True),
    dict(type='DecordDecode'),
    dict(type='Resize', scale=(-1, 256)),
    dict(type='CenterCrop', crop_size=224),
    dict(type='FormatShape', input_format='NCTHW'),
    dict(type='PackActionInputs')
]
test_pipeline = [
    dict(type='DecordInit'),
    dict(
        type='SampleFrames',
        clip_len=16,
        frame_interval=4,
        num_clips=10,
        test_mode=True),
    dict(type='DecordDecode'),
    dict(type='Resize', scale=(-1, 224)),
    dict(type='CenterCrop', crop_size=224),
    dict(type='FormatShape', input_format='NCTHW'),
    dict(type='PackActionInputs')
]

repeat_sample = 2
train_dataloader = dict(
    batch_size=16,
    num_workers=8,
    persistent_workers=True,
    sampler=dict(type='DefaultSampler', shuffle=True),
    collate_fn=dict(type='repeat_pseudo_collate'),
    dataset=dict(
        type='RepeatAugDataset',
        num_repeats=repeat_sample,
        ann_file=ann_file_train,
        data_prefix=dict(video=data_root),
        pipeline=train_pipeline))
val_dataloader = dict(
    batch_size=16,
    num_workers=8,
    persistent_workers=True,
    sampler=dict(type='DefaultSampler', shuffle=False),
    dataset=dict(
        type=dataset_type,
        ann_file=ann_file_val,
        data_prefix=dict(video=data_root_val),
        pipeline=val_pipeline,
        test_mode=True))
test_dataloader = dict(
    batch_size=1,
    num_workers=8,
    persistent_workers=True,
    sampler=dict(type='DefaultSampler', shuffle=False),
    dataset=dict(
        type=dataset_type,
        ann_file=ann_file_test,
        data_prefix=dict(video=data_root_val),
        pipeline=test_pipeline,
        test_mode=True))

val_evaluator = dict(type='AccMetric')
test_evaluator = val_evaluator

train_cfg = dict(
    type='EpochBasedTrainLoop', max_epochs=100, val_begin=1, val_interval=1)
val_cfg = dict(type='ValLoop')
test_cfg = dict(type='TestLoop')

base_lr = 9.6e-3
optim_wrapper = dict(
    optimizer=dict(
        type='AdamW', lr=base_lr, betas=(0.9, 0.999), weight_decay=0.05),
    constructor='LearningRateDecayOptimizerConstructor',
    paramwise_cfg={
        'decay_rate': 0.75,
        'decay_type': 'layer_wise',
        'num_layers': 16
    },
    clip_grad=dict(max_norm=5, norm_type=2))

param_scheduler = [
    dict(
        type='LinearLR',
        start_factor=1 / 600,
        by_epoch=True,
        begin=0,
        end=20,
        convert_to_iter_based=True),
    dict(
        type='CosineAnnealingLR',
        T_max=80,
        eta_min_ratio=1 / 600,
        by_epoch=True,
        begin=20,
        end=100,
        convert_to_iter_based=True)
]

default_hooks = dict(
    checkpoint=dict(interval=3, max_keep_ckpts=20), logger=dict(interval=100))

# Default setting for scaling LR automatically
#   - `enable` means enable scaling LR automatically
#       or not by default.
#   - `base_batch_size` = (8 GPUs) x (64 samples per GPU) / repeat_sample.
auto_scale_lr = dict(enable=True, base_batch_size=512 // repeat_sample)