Video Player: Pitch Shift

[Erkki2]

Hello! I’m developing a video player for playing karaoke videos. One useful feature would be to change the key of a song while playing back. So how could I modify the audio stream of a video while playing back in a QT application? There seemed to be hardly any information about this.

[Erkki2]

It has been a while. Is this even possible with qt? Anyway, it would be extremely helpful if anyone could answer to even one of the following questions:
- How could I separate audio from a video file?
- How could I change the audio track of the currently playing video?
- Are there any other libraries that could help?

[anda_skoa]

What kind of API are you using right now?

Cheers,
_

[Erkki2]

I'm pretty much still designing the program. I haven't really started programming yet (apart from some tests), because I try to figure out these problems before making technology decisions. It seems that the easiest way to create a video player would be using QMediaPlayer class, but I believe that for the pitch shift I'll need something less automated.

[anda_skoa]

You might have to use a more low-level API, e.g. Qt bindings to GStreamer

Cheers,
_