Develop a dll library that works with the rtsp stream

Develop a dll library that works with the rtsp stream of the IP camera (the camera can be any) using Delphi or C ++ (comments to the source code and description of the components used are required). The library should implement the following functions: SaveVideo (rtspaddr, time, filename) - save the video to a file named filename with the length of time seconds (integer from 1 to 600) from the rtsp stream with the address rtspaddr; SaveJPG (rtspaddr, filename) - save frame in JPG format to file named filename from rtsp stream with rtspaddr address.