Use Case
When uploading certain PowerPoint files as lectures in the LMS, image quality may appear degraded in the web view. This issue typically affects files that use bitmap-based slide backgrounds or elements. While the original PowerPoint file may appear crisp when viewed locally, the same file can exhibit reduced visual quality after being uploaded to the LMS.
Explanation
The image quality degradation is primarily due to two factors:
- The presentation includes bitmap-specific backdrops that are optimized for display in Microsoft Office.
- Schoox uses a headless version of LibreOffice—typically through Filestack or local conversion—to render PowerPoint files. This rendering method does not fully support or preserve the quality of these bitmap elements, leading to reduced visual fidelity in the uploaded lecture.
Workarounds
While a direct fix is not currently available within the LMS, the following workarounds can help preserve image quality:
- Export as PDF:
Save the PowerPoint presentation as a PDF using Microsoft Office, and then upload the PDF to the LMS. This method preserves the original formatting and visual clarity. - Convert via Google Slides:
Upload the PowerPoint file to Google Slides, then re-export it as a new PPTX file. Google Slides often processes bitmap content into a format that is more compatible with the LMS rendering engine, resulting in improved display quality.
Important Note
This behavior is a known limitation of the LibreOffice rendering engine used during file conversion. At this time, there is no LMS-side resolution available. We recommend using one of the above workarounds to ensure the best possible viewing experience for your learners.