dify doesn't seem to support parsing image-only PDF files

[Tuyohai]

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Dify version

0.11.2

Cloud or Self Hosted

Cloud

Steps to reproduce

Upload image-only PDF to the knowledge base.

✔️ Expected Behavior

Parse out the text in the image.

❌ Actual Behavior

The parsed result is empty.

[dosubot]

Hey @Tuyohai! I'm here to assist you with any bugs, questions, or contributions for Dify. Let's tackle this issue together!

I found a similar unsolved discussion regarding Dify's ability to parse images in PDFs and embed them into vector databases ^[1]. Additionally, there are no existing solutions or built-in OCR capabilities in Dify for extracting text from images within PDFs. The current PDF processing in Dify uses the pypdfium2 library, which does not support OCR for image-only PDFs ^[2].

To extend Dify's capabilities to include OCR for image-only PDFs, you might need to integrate an OCR library like Tesseract or a similar tool that can handle image-based text extraction.

To continue talking to Dosu, mention @dosu.

[Tuyohai]

Whether to consider adding OCR recognition, may deploy an OCR model, or use a third-party service like the LLM Service

[crazywoola]

#10829 We do have a tool pending on review.

[dosubot]

Hi, @Tuyohai. I'm Dosu, and I'm helping the Dify team manage their backlog. I'm marking this issue as stale.

Issue Summary:

• You reported that Dify version 0.11.2 cannot parse text from image-only PDF files.
• I noted the lack of OCR capabilities and suggested integrating an OCR library.
• You inquired about adding OCR recognition or using a third-party service.
• Crazywoola mentioned a pending tool review that might resolve this issue, linking to a pull request.

Next Steps:

• Please let us know if this issue is still relevant to the latest version of Dify. You can keep the discussion open by commenting on the issue.
• If there is no further activity, this issue will be automatically closed in 15 days.

Thank you for your understanding and contribution!