Pitch Change; VLC Objects; Time Stretching

[PlasmaGrass]

Hi, guys, what's up?

I am a newcomer here, pleased to meet you.

I am currently working on making a simple karaoke player for my project, using libvlc. I am required to make some pitch changed to the now playing video / song. I can change the playback rate, so that it plays faster, however I do want the pitch to be altered. It is currently stays at the same pitch due to "Enable Time Stretching" is on. I want to turn it off, but I cannot find in the documentation anywhere that mention this. I cannot pass command line arguments to the libvlc, is there another way? Is it using the vlc_object_t ?

Another alternative, is it possible to change the pitch of the song without altering the tempo?

Finally, where can I find the documentation of libvlc? Is https://www.videolan.org/developers/vlc ... dules.html the most up to date reference? Because I believe there are some uncommented section here and there...

Thank you.

[Jean-Baptiste Kempf]

You need to disable the option in your libvlc_new parameters.

[PlasmaGrass]

Alright, it works!
Thank you!
Could someone please explain how to change pitch without the tempo? Thanks.

[Jean-Baptiste Kempf]

You cannot.

[PlasmaGrass]

You cannot.

Ah, what a bummer
Is it not possible to, say, tap the output from audio codec, before it's output to the speaker? I understand that if I can tap into it, I could do ring buffer to lower pitch in real time. How can I tap into it?

I appreciate any hints on it.

[Jean-Baptiste Kempf]

Use amem callbacks.