There is a transcription of a song https://www.youtube.com/watch?v=IfcS-w808dM that I put in a video. Youtube obviously noted me that it is copyrighted and told me that it might put ads in my video. Can transcriptions actually have a copyright as they are not original compositions? If not, would I still need to get permission from the original author?
A transcription can be a creative work, so it can be protected by copyright (no commitment about that particular instance). A transcription is copying and transforming an original work in a particular (symbolic). The original work that the transcription is based on is also protected by copyright, so to make the copy that embodies the transcription, you need permission from the original rights holder. Splicing the transcription onto an illegal copy of an original performance is also copyright infringement, but resynthesis based on the transcription is not. A transcription also might not be entitled to copyright protection, if it is the product of a computer program, since feeding a sound file into a program is not a creative activity. (The program that generated the transcription is, of course, protected by copyright).