# LagrangeInterpolator with fractional ratio

**URL:** https://forum.juce.com/t/lagrangeinterpolator-with-fractional-ratio/32457
**Category:** General JUCE discussion
**Created:** [March 23, 2019, 5:10pm UTC](https://forum.juce.com/t/lagrangeinterpolator-with-fractional-ratio/32457 "2019-03-23T17:10:49Z")
**Posts on this page:** 1
**Showing post:** 8

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### Author: ![pauloesteban](https://avatars.discourse-cdn.com/v4/letter/p/a5b964/32.png) [@pauloesteban](https://forum.juce.com/u/pauloesteban)
#### Post date: [July 19, 2019, 8:50am UTC](https://forum.juce.com/t/lagrangeinterpolator-with-fractional-ratio/32457/8 "2019-07-19T08:50:22Z")

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@Daniel Found this use of LagrangeInterpolator for resampling.

> [@Resampling Audio using Lagrange Interpolator](https://forum.juce.com/t/resampling-audio-using-lagrange-interpolator/26209/2):
>
> void fileConvert(const File& file, const double& dOutSampleRate) { AudioFormatManager formatManager; formatManager.registerBasicFormats(); AudioFormatReader\* reader = formatManager.createReaderFor(file); if (reader) { if (reader-\>lengthInSamples \> 0) { if (reader-\>sampleRate != dOutSampleRate) { //find the out file number of samples juce::int64 iSamples = ceil(dOutSampleRate \* reader-\>lengthInSamples / reader-\>sampleRate); AudioSampleBuffer tempBuffer(reader-\>numChannels, iS…

Apparently it works if it is applied to the whole file not buffering. In the case of realtime are you suggesting using an AbstractFIFO?

Many thanks in advance.

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