Feature Request: Expose libsoxr's Variable-Rate Resampling (soxr_set_io_ratio)

[vrunk11]

Summary

Request to expose libsoxr's variable-rate resampling functionality through the Python API, specifically the soxr_set_io_ratio() function that allows dynamic rate changes during streaming.

Motivation

Variable-rate resampling is useful for several applications:

• Time-base correction (TBC) for video processing with wow/flutter correction
• Real-time audio processing with dynamic pitch/speed changes
• Audio synchronization where the rate needs to change during playback
• Digital signal processing applications requiring non-uniform resampling

Current Limitation

The current ResampleStream API only supports fixed-rate resampling. While libsoxr has excellent variable-rate support (see example #5), this functionality isn't exposed in the Python wrapper.

Proposed API

Add support for variable-rate resampling to ResampleStream:

# Enable variable-rate mode
rs = soxr.ResampleStream(44100, 16000, 1, variable_rate=True)

# Process chunks normally
output1 = rs.resample_chunk(chunk1)

# Change the resampling ratio dynamically
rs.set_io_ratio(48000/44100, slew_len=1024)

# Continue processing with new ratio
output2 = rs.resample_chunk(chunk2)

[dofuuz]

I'll take a look into it... but since I don’t use this feature myself, I don’t think I’ll be working on it in a fast manner. Sorry.

[dofuuz]

Variable-rate resampling added to main branch.

You can test it with:

pip install git+https://github.com/dofuuz/python-soxr.git

Test please, and let me know if there are any errors or if you have any feedback on its usage.

It would be great if you can provide test case codes.

[vrunk11]

Thanks a lot, we are going to get around testing it out on our project ld-decode😁