Before uploading the files there is an option to Make background transparent. When checked, the white of the PDF will be transparent and when unchecked, a traditional white paper background will be displayed. This option is presented when the PDF is added as a layer on the map in SYNCHRO Control.
To upload a PDF file, you can either drag and drop or click browse and navigate to the pdf file location.
You will see the upload process window pop up, with the progress of extracting the PDF file to sheets.