About the grayscale conversion - you may import the PDF file and iterate its content by changing the colors to gray. I am attaching a sample project showing how to import PDF file with colors, change the colors of the Path, TextFragment and Image instances and finally view the modified file.
As for the compression - when you import and then export some existing PDF file with RadPdfProcessing the exported file is always compressed the best way RadPdfProcessing can. So if the original file has uncompressed content RadPdfProcessing will compress it on export. The only property that allows you to change the default RadPdfProcessing compression is PdfExportSettings ImageQuality
property. Using this property you may export images in the PDF file with better compression at the expense of image quality.
I hope this is helpful. If you have any other questions or concerns please do not hesitate to contact us again.
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