model = dict(
    type='VoteNet',
    backbone=dict(
        type='PointNet2SASSG',
        in_channels=4,
        num_points=(2048, 1024, 512, 256),
        radius=(0.2, 0.4, 0.8, 1.2),
        num_samples=(64, 32, 16, 16),
        sa_channels=((64, 64, 128), (128, 128, 256), (128, 128, 256),
                     (128, 128, 256)),
        fp_channels=((256, 256), (256, 256)),
        norm_cfg=dict(type='BN2d'),
        sa_cfg=dict(
            type='PointSAModule',
            pool_mod='max',
            use_xyz=True,
            normalize_xyz=True)),
    bbox_head=dict(
        type='VoteHead',
        vote_module_cfg=dict(
            in_channels=256,
            vote_per_seed=1,
            gt_per_seed=3,
            conv_channels=(256, 256),
            conv_cfg=dict(type='Conv1d'),
            norm_cfg=dict(type='BN1d'),
            norm_feats=True,
            vote_loss=dict(
                type='ChamferDistance',
                mode='l1',
                reduction='none',
                loss_dst_weight=10.0)),
        vote_aggregation_cfg=dict(
            type='PointSAModule',
            num_point=256,
            radius=0.3,
            num_sample=16,
            mlp_channels=[256, 128, 128, 128],
            use_xyz=True,
            normalize_xyz=True),
        pred_layer_cfg=dict(in_channels=128, shared_conv_channels=(128, 128)),
        conv_cfg=dict(type='Conv1d'),
        norm_cfg=dict(type='BN1d'),
        objectness_loss=dict(
            type='CrossEntropyLoss',
            class_weight=[0.2, 0.8],
            reduction='sum',
            loss_weight=5.0),
        center_loss=dict(
            type='ChamferDistance',
            mode='l2',
            reduction='sum',
            loss_src_weight=10.0,
            loss_dst_weight=10.0),
        dir_class_loss=dict(
            type='CrossEntropyLoss', reduction='sum', loss_weight=1.0),
        dir_res_loss=dict(
            type='SmoothL1Loss', reduction='sum', loss_weight=10.0),
        size_class_loss=dict(
            type='CrossEntropyLoss', reduction='sum', loss_weight=1.0),
        size_res_loss=dict(
            type='SmoothL1Loss', reduction='sum', loss_weight=10.0 / 3.0),
        semantic_loss=dict(
            type='CrossEntropyLoss', reduction='sum', loss_weight=1.0)))
# model training and testing settings
train_cfg = dict(pos_distance_thr=0.3, neg_distance_thr=0.6, sample_mod='vote')
test_cfg = dict(
    sample_mod='seed', nms_thr=0.25, score_thr=0.05, per_class_proposal=True)
