Source code for nemo_automodel.datasets.vlm.collate_fns

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#     http://www.apache.org/licenses/LICENSE-2.0
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import torch

from nemo_automodel.datasets.vlm.utils import extract_skipped_token_ids
from nemo_automodel.shared.import_utils import MISSING_QWEN_VL_UTILS_MSG
from unittest.mock import MagicMock

try:
    from qwen_vl_utils import process_vision_info

    HAVE_QWEN_VL_UTILS = True
except ImportError:
    HAVE_QWEN_VL_UTILS = False
    process_vision_info = MagicMock()


[docs] def qwen2_5_collate_fn(examples: list, processor) -> dict[str, torch.Tensor]: """Collate function for Qwen2.5 VL model.""" if not HAVE_QWEN_VL_UTILS: raise ImportError(MISSING_QWEN_VL_UTILS_MSG) skipped_tokens = extract_skipped_token_ids(processor) texts = [processor.apply_chat_template(example["conversation"], tokenize=False) for example in examples] image_inputs = [process_vision_info(example["conversation"])[0] for example in examples] batch = processor( text=texts, images=image_inputs, padding=True, return_tensors="pt", ) labels = batch["input_ids"].clone()[:, 1:] labels = torch.cat([labels, -100 * torch.ones_like(labels[:, :1])], dim=1) labels[torch.isin(labels, skipped_tokens)] = -100 batch["labels"] = labels return batch
[docs] def default_collate_fn(examples: list, processor) -> dict[str, torch.Tensor]: """Default collate function for VLM models.""" if not HAVE_QWEN_VL_UTILS: raise ImportError(MISSING_QWEN_VL_UTILS_MSG) skipped_tokens = extract_skipped_token_ids(processor) batch = processor.apply_chat_template( [example["conversation"] for example in examples], tokenize=True, add_generation_prompt=False, return_tensors="pt", return_dict=True, ) batch["pixel_values"] = batch["pixel_values"].to(torch.bfloat16) labels = batch["input_ids"].clone()[:, 1:] labels = torch.cat([labels, -100 * torch.ones_like(labels[:, :1])], dim=1) labels[torch.isin(labels, skipped_tokens)] = -100 batch["labels"] = labels return batch
# Mapping of processor types to their collate functions COLLATE_FNS = { "Qwen2_5_VLProcessor": qwen2_5_collate_fn, "default": default_collate_fn, }