Error processing PPT file: "no embedded image" in Docling server

I encountered an issue when using Docling. After uploading a PPT file, the job failed, and the server logs show the following:

`
docling-server | ERROR:docling_jobkit.orchestrators.local.worker:Worker 1 failed to process job a3358f81-f850-48d8-bebe-6280d1cc2f68: no embedded image
docling-server | INFO: 127.0.0.1:58802 - "GET /v1/status/poll/a3358f81-f850-48d8-bebe-6280d1cc2f68?wait=5 HTTP/1.1" 200 OK
docling-server | ERROR:docling_serve.gradio_ui:Error processing file(s): Task failed with status 'failure'

`
Steps to reproduce:
1.Start the Docling server.
2.Upload a PPT file via the Gradio interface or API.
3.The job fails with status failure, and the server logs show "no embedded image" error.

Environment:
docling-server：1.8.0

Attachments：

[问题页.pptx](https://github.com/user-attachments/files/23642496/default.pptx)