FS#5420 - Pitch preservation for speed change (pitch-shifter algorithm)

Attached to Project: Rockbox
Opened by Anonymous Submitter - Wednesday, 24 May 2006, 05:51 GMT
Task Type Feature Requests
Category Music playback
Status Closed
Assigned To No-one
Operating System All players
Severity Low
Priority Normal
Reported Version
Due in Version Undecided
Due Date Undecided
Percent Complete 100%
Votes 0
Private No


A function analogous to pitch-shifter algorithms, wherein pitch is preserved for speed changes in the pitch window.
This should be possible by crossfading between small variable-length overlapping (approx. 25-50%) chunks (for reduced speed pitch preservation)
and by doing the same between `gapped' variable-length chunks for pitch-preservation for increased speed settings.
Although probably of too poor a quality for music, such a function could prove invaluable for speech/the reading of audio books/material.
This task depends upon

Closed by  Bj√∂rn Stenberg (zagor)
Wednesday, 20 September 2006, 23:07 GMT
Reason for closing:  Duplicate
Additional comments about closing:  Closing all feature requests.
Comment by Sal (DiLate) - Wednesday, 31 May 2006, 01:01 GMT

i would LOVE it.. but i dont think the devs are down for that one..

believe its been requested before
Comment by Patrick Gavin (wezelboy) - Friday, 02 June 2006, 20:45 GMT
I'd love it too. Maybe I'm talking out of my ass, but since most audio compression formats work in the frequency domain, shouldn't this just be a matter of adjusting the base frequency before converting back to the time domain and then adjusting the sample rate?
Comment by olivier arsac (neoliv) - Wednesday, 07 June 2006, 22:23 GMT
I'm listening to a lot of audio-books with speed at 130..150% (depending on reader). This is really useful but the higher pitch is a limitation and well... ruins a bit the pleasure :)
Having a way to increase speed without too much of a pitch change would really by a BIG win for all the audio-book readers! (mostly visualy impaired people I guess)
Hope someone will do this one rather tnan another usele^H^H^H^Hfuny game o:)