PDFToImageContent

Convert PDF files to ImageContent objects for multimodal AI processing. Each converted page becomes a separate ImageContent object containing base64-encoded image data and associated metadata.

Key Features

• Converts PDF pages to ImageContent objects with base64-encoded image data.
• Supports converting specific pages or page ranges from a PDF document.
• Configurable image detail level for models that support it (such as OpenAI).
• Resizes images to reduce file size, memory usage, and processing time.
• Includes source file and page number metadata in each ImageContent object.
• Connects to ChatPromptBuilder for including PDF page images in multimodal prompts.

Configuration

1. Drag the PDFToImageContent component onto the canvas from the Component Library.
2. Click the component to open the configuration panel.
3. Configure the parameters as needed.

Connections

PDFToImageContent accepts a list of PDF file paths or ByteStream objects (sources) as input, along with optional metadata (meta), detail level (detail), image size (size), and page range (page_range). It outputs a list of ImageContent objects (image_contents).

Typically, PDFToImageContent receives PDF files from FilesInput or filtered from FileTypeRouter. Its image_contents output connects to ChatPromptBuilder to include the extracted page images in a multimodal prompt for a vision-enabled model.

Usage Example

Using the component in a pipeline

This example shows a query pipeline that uses PDFToImageContent to convert uploaded PDF pages to images for multimodal AI processing. The pipeline extracts specified pages from PDF documents, converts them to ImageContent objects, and sends them to a vision-enabled chat model for analysis.

components:
  PDFToImageContent:
    type: haystack.components.converters.image.PDFToImageContent
    init_parameters:
      detail: auto
      size:
      page_range:
        - "1-3"
  ChatPromptBuilder:
    type: haystack.components.builders.chat_prompt_builder.ChatPromptBuilder
    init_parameters:
      template:
        - role: system
          content: >-
            You are an AI assistant that analyzes PDF documents. Examine the
            provided PDF pages and answer questions about their content,
            layout, text, images, and any other visible elements.
        - role: user
          content: "{{ question }}"
          images: "{{ images }}"
      required_variables:
        - question
        - images
  OpenAIChatGenerator:
    type: haystack.components.generators.chat.openai.OpenAIChatGenerator
    init_parameters:
      api_key:
        type: env_var
        env_vars:
          - OPENAI_API_KEY
        strict: true
      model: gpt-4o
      generation_kwargs:
  OutputAdapter:
    type: haystack.components.converters.output_adapter.OutputAdapter
    init_parameters:
      template: "{{ replies[0].text }}"
      output_type: str
  DeepsetAnswerBuilder:
    type: deepset_cloud_custom_nodes.augmenters.deepset_answer_builder.DeepsetAnswerBuilder
    init_parameters:
      reference_pattern:

connections:
  - sender: PDFToImageContent.image_contents
    receiver: ChatPromptBuilder.images
  - sender: ChatPromptBuilder.prompt
    receiver: OpenAIChatGenerator.messages
  - sender: OpenAIChatGenerator.replies
    receiver: OutputAdapter.replies
  - sender: OutputAdapter.output
    receiver: DeepsetAnswerBuilder.replies

inputs:
  query:
    - ChatPromptBuilder.question
  files:
    - PDFToImageContent.sources

outputs:
  answers: DeepsetAnswerBuilder.answers

Parameters

Inputs

Parameter	Type	Default	Description
sources	List[Union[str, Path, ByteStream]]		List of PDF file paths or ByteStream objects to convert.
meta	Optional[Union[Dict[str, Any], List[Dict[str, Any]]]]	None	Optional metadata to attach to the ImageContent objects. This value can be a list of dictionaries or a single dictionary. If it's a single dictionary, its content is added to the metadata of all produced ImageContent objects. If it's a list, its length must match the number of sources as they're zipped together. For ByteStream objects, their meta is added to the output ImageContent objects.
detail	Optional[Literal["auto", "high", "low"]]	None	Optional detail level of the image (only supported by OpenAI). Possible values: - "auto" - "high" - "low" This is passed to the created ImageContent objects.
size	Optional[Tuple[int, int]]	None	If provided, resizes the image to fit within the specified dimensions (width, height) while maintaining aspect ratio. If not provided, the size value is the one set in the constructor.
page_range	Optional[List[Union[str, int]]]	None	List of page numbers and page ranges to convert to images. If not provided, the page range is the one set in the pipeline configuration.

Outputs

Parameter	Type	Default	Description
image_contents	List[ImageContent]		A list of ImageContent objects created from the PDF pages.

Init Parameters

These are the parameters you can configure in Pipeline Builder:

Parameter	Type	Default	Description
detail	Optional[Literal["auto", "high", "low"]]	None	Optional detail level of the image (only supported by OpenAI). Possible values: - "auto" - "high" - "low" This is passed to the created ImageContent objects.
size	Optional[Tuple[int, int]]	None	If provided, resizes the image to fit within the specified dimensions (width, height) while maintaining aspect ratio. This reduces file size, memory usage, and processing time.
page_range	Optional[List[Union[str, int]]]	None	List of page numbers and page ranges to convert to images. Page numbers start at 1. If None, all pages in the PDF are converted. Also accepts printable range strings, for example:: ['1-3', '5', '8', '10-12'].

Run Method Parameters

These are the parameters you can configure for the component's run() method. This means you can pass these parameters at query time through the API, in Playground, or when running a job. For details, see Modify Pipeline Parameters at Query Time.

Parameter	Type	Default	Description
sources	List[Union[str, Path, ByteStream]]		List of PDF file paths or ByteStream objects to convert.
meta	Optional[Union[Dict[str, Any], List[Dict[str, Any]]]]	None	Optional metadata to attach to the ImageContent objects. This value can be a list of dictionaries or a single dictionary. If it's a single dictionary, its content is added to the metadata of all produced ImageContent objects. If it's a list, its length must match the number of sources as they're zipped together. For ByteStream objects, their meta is added to the output ImageContent objects.
detail	Optional[Literal["auto", "high", "low"]]	None	Optional detail level of the image (only supported by OpenAI). This is passed to the created ImageContent objects. If not provided, the detail level is the one set in the constructor.
size	Optional[Tuple[int, int]]	None	If provided, resizes the image to fit within the specified dimensions (width, height) while maintaining aspect ratio. If not provided, the size value is the one set in the constructor.
page_range	Optional[List[Union[str, int]]]	None	List of page numbers and page ranges to convert to images. Page numbers start at 1. If None, all pages in the PDF are converted. Pages outside the valid range are skipped with a warning. Also accepts printable range strings, for example: ['1-3', '5', '8', '10-12'].