Need transcoder software with gui for transcoding multiple streams. FFMPEG ok.

Hi all; Here is what I need. This can be in linux or windows. I need an installation of ffmpeg that will transcode multiple streams with rtmp out. Ie gui where I can create a stream Input stream TS Mpeg4 Output RTMP 720p or 576p with options for fast or slow transcode. Other controls are nice to have also. Needs to be able to handle multiple streams for ffmpeg Your welcome to make suggestions for best efficient transcoder options.