AviSynth

The are various types of tools that can be used for video post-production, and those who want to speed things up can rely on apps without any graphical interface, using solely specialized scripts. Such a software solution is AviSynth.
Since this product only works with scripts, beginners need to take the time to go through the documentation and learn how to write these lines of code. Once they get accustomed with the language and the commands, they can start experimenting with simple and complex scripts, depending on the action they want to perform.
In order to write a script, one simply needs to open a text editor (even one as simple as Notepad will suffice) and write the corresponding lines. Then, save the file as *.avs, and open it using Windows Media Player, Media Player Classic, VirtualDub, VirtualDubMod, MPlayer, GOM Player, SUPER or Total Video Converter.
Also, it needs to be mentioned that AviSynth can process most video and audio formats, yet it all depends on the codecs one has previously installed on their PC.
Considering AviSynth does not come with a dedicated GUI, users spend less time waiting for the editing process to complete, and more time focusing on the actions they need, such as cutting segments from the videos or enhancing them with a fade-in or fade-out option.
Users can combine simple actions and create complex series of effects, so that when playing the script the result would be both satisfying and effortless. Basically, once loaded into a compatible multimedia player, the generated script is read as if it were an actual video, so no additional input is required from the user.
To sum it up, AviSynth might require learning some new commands to use in the post-processing of one’s video, yet the result is much faster than it would be with traditional apps featuring a GUI.