GNU Cobol is interesting, but note that most COBOL running in production is using other compilers and operating systems. MicroFocus and IBM COBOL are the most popular ones. They are usually executed on IBM operating systems like z/OS or IBM i, which have a hardware a bit different from a normal PC/server.
VLC ships their own codecs which is great on Windows, but a bit suboptimal on a typical Linux desktop installation since you’re probably going to have GStreamer or ffmpeg available too for the rest of the software like video editors, web browsers, etc