Add new Data Collators

VISSL allows implementing new data collators easily. Follow the steps below:

• Step1: Create the new data collator my_new_collator.py under vissl/data/collators/my_new_collator.py following the template.

import torch
from vissl.data.collators import register_collator

@register_collator("my_new_collator")
def my_new_collator(batch, param1 (Optional), ...):
    """
    add documentation on what new collator does

    Input:
        add documentation on what input type should the collator expect. i.e
        what should the `batch' look like.

    Output:
        add documentation on what the collator returns i.e. what does the
        collated data `output_batch' look like.
    """
    # implement the collator
    ...
    ...

    output_batch = {
        "data": ... ,
        "label": ... ,
        "data_valid": ... ,
        "data_idx": ... ,
    }
    return output_batch

• Step2: Use your new collator via the configuration files

DATA:
  TRAIN:
    COLLATE_FUNCTION: my_new_collator
    COLLATE_FUNCTION_PARAMS: {...}  # optional, specify params if collator requires any