hiyouga/LlamaFactory · error · ValueError

This model does not support image input. Please check whethe

Error message

This model does not support image input. Please check whether the correct `template` is used.

What it means

ValueError from BasePlugin._validate_inputs during multimodal preprocessing: the sample contains images, but the active mm_plugin/template defines no image_token (e.g. the plugin's IMAGE_TOKEN is None), meaning this model/template combination has no image input support. It is a template-vs-modality mismatch, detected before any processor call.

Source

Thrown at src/llamafactory/data/mm_plugin.py:163

    expand_mm_tokens: bool = True

    def _validate_input(
        self,
        processor: Optional["MMProcessor"],
        images: list["ImageInput"],
        videos: list["VideoInput"],
        audios: list["AudioInput"],
    ) -> None:
        r"""Validate if this model accepts the input modalities."""
        image_processor: BaseImageProcessor = getattr(processor, "image_processor", None)
        video_processor: BaseImageProcessor = getattr(
            processor, "video_processor", getattr(processor, "image_processor", None)
        )
        feature_extractor: SequenceFeatureExtractor = getattr(processor, "feature_extractor", None) or getattr(
            processor, "audio_processor", None
        )
        if len(images) != 0 and self.image_token is None:
            raise ValueError(
                "This model does not support image input. Please check whether the correct `template` is used."
            )

        if len(videos) != 0 and self.video_token is None:
            raise ValueError(
                "This model does not support video input. Please check whether the correct `template` is used."
            )

        if len(audios) != 0 and self.audio_token is None:
            raise ValueError(
                "This model does not support audio input. Please check whether the correct `template` is used."
            )

        if self.image_token is not None and processor is None:
            raise ValueError("Processor was not found, please check and update your model file.")

        if self.image_token is not None and image_processor is None:
            raise ValueError("Image processor was not found, please check and update your model file.")

View on GitHub (pinned to f28afaf635)

Solutions

  1. Set template in the YAML to the model's official multimodal template (e.g. qwen, llava, mllama) so an image-capable plugin is selected.
  2. Confirm model_name_or_path points to the full multimodal checkpoint, not the language-model-only backbone.
  3. If training text-only, remove images/`<image>` placeholders from the dataset.
  4. Check data/template.py to verify the chosen template registers an mm_plugin with an image token.

Example fix

# before (train.yaml for Qwen2-VL)
template: llama3

# after
template: qwen
Defensive patterns

Strategy: validation

Validate before calling

# before training: confirm the chosen plugin supports images
from llamafactory.data.template import get_template_and_fix_tokenizer
# plugin check happens at preprocessing; cheap proxy:
def template_supports_image(template_name: str, mm_plugins: dict) -> bool:
    return mm_plugins.get(template_name, {}).get("image_token") is not None

Prevention

When it happens

Trigger: Using a multimodal dataset (images column or <image> placeholders) with a text-only template (e.g. default llama template) or a template whose registration maps to a plugin without image support; setting a vision model's template string incorrectly so the wrong plugin is selected.

Common situations: Fine-tuning a VLM (Qwen-VL, Llava, etc.) while leaving template: default or a chat template from the base LLM; forgetting to switch the template after changing model_name_or_path to a multimodal checkpoint.

Related errors

AI-assisted analysis of hiyouga/LlamaFactory@f28afaf635 (2026-08-14). Data as JSON: /api/errors/75f56a911d096b3f. Report an issue: GitHub.