If you have uploaded a PDF file to Vitrium and the images in the web viewer appear distorted, grainy, or have lost some of their original quality compared to the original file, then you may be able to resolve this by optimizing the original PDF file in Adobe.
Try Adobe's built-in optimization tool in Adobe Acrobat and refer to the following screenshots for our recommended settings.
Alternatively, if you use Adobe InDesign to create your PDF content, click here to review our suggested PDF Export Settings in Adobe InDesign.
Recommended Settings in PDF Optimizer in Adobe Acrobat
If you tried these settings and it still did not help resolve the the distorted images, then please submit a ticket to the Vitrium team and include your original PDF file.