Pitch / Speed Shifter for VS1010d

Designing hardware and software for systems that use the VS1010 MP3 Audio DSP Microcontroller.
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Henrik
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Pitch / Speed Shifter for VS1010d

Post by Henrik » Thu 2021-02-18 13:23

Hello!

It is with greate pleasure that I bring to you the Pitch / Speed Shifter for VS1010d. This device driver has earlier existed for VS1005, but now it has been ported for VS1010, too.

The Pitch / Speed shifter allows for independent control of an MP3 file's playback speed and pitch. It can be used in various applications, including but not limited to:
  • DJ usage where it is very useful to be able to control playback speed and pitch independently.
  • Language learning where adjusting speed without affecting pitch is very useful.
  • Audio book devices where speed control without affecting pitch is convenient.
  • Karaoke devices where pitch control can be used to match the range of the karaoke singer.
I hope this piece of software proves useful to you!

Kind regards,
- Henrik
Attachments
FtPitch.zip
Pitch / Speed Shifter driver and control program. See README.TXT for details.
(54.26 KiB) Downloaded 10 times
TreePlayer3.zip
Example player that demonstrated speed and pitch controls. See README.TXT for details.
(31.91 KiB) Downloaded 8 times
ParamSpl.zip
Support function required by SetPitch. Install to S:SYS/
(7.2 KiB) Downloaded 9 times
Good signatures never die. They just fade away.

kenc
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Location: Ontario, Canada

Re: Pitch / Speed Shifter for VS1010d

Post by kenc » Thu 2021-02-18 22:00

Henrik,

Thank you for your work on this!

I have the ftpitch driver + TreePlayer3 running on my 1010D Minidemo board, and I noticed an artifact (click sound) when the speed is first slowed down or pitch increased. I've tried this with different MP3 files (all 16-bit, 44.1Khz sample rate, 192Kbps CBR). It also happens playing WAV/LPCM files (16-bit, both 44.1Khz and 48Khz files). I also tried using two different microSD cards, a Sandisk consumer-grade card and a Sandisk Industrial card for embedded systems.

TP3
Base pitch & speed playback ok
Press s (*CLICK* sound)
Press b (back at base speed, playback ok)
Press f (playback ok)
Press b (playback still ok)
Press s (*CLICK* sound)
Press s (playback ok)
etc.

So fbfbfb... is fine, but sbsbsb... causes clicks

TP3
Base pitch & speed playback ok
Press + (*CLICK* sound)
Press + (playback ok)
Press - (playback ok)
Press - (back at base pitch, playback ok)
Press - (below base pitch, playback still ok)
Press + (back to base pitch, playback ok)
Press + (*CLICK* sound)

So -=-=-=... is fine, but +=+=+=... causes clicks.

EDIT: I noticed that there's no clicking the first time I press s or + after rebooting the minidemo board, but after a couple times pressing s or + the clicking gets louder.

Thanks!
Ken

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Henrik
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Re: Pitch / Speed Shifter for VS1010d

Post by Henrik » Mon 2021-02-22 6:33

Hello Ken,

excellent that you have already tried the Pitch / Speed Shifter!

I'll have to see whether I can repeat your issue and if so, what the solution would be.

Kind regards,
- Henrik
Good signatures never die. They just fade away.

kenc
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Posts: 10
Joined: Tue 2021-02-09 3:41
Location: Ontario, Canada

Re: Pitch / Speed Shifter for VS1010d

Post by kenc » Mon 2021-02-22 6:40

Thank you, Henrik. I can make an audio recording,
if it would help. Or send you the files I’m testing with.

Best,
Ken

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