Add Digital Signature on a PDF Document
To add a digital signature to a PDF document, first, create a digital ID and digital signature. After that, add the Digital Signature to the PDF document.
How to Merge PDF Files Using the Command Line on Ubuntu
PDF format is the most popular for sharing documents. You can merge PDFs if you need to show a single PDF divided into multiple parts.
FFMpeg Extract Audio
FFMpeg is a free and open-source video and audio converter. It has been widely adopted by many applications, including VLC discussed in this article.