Add resampleAudioBuffer utility

[KristinnRoach]

Exports resampleAudioBuffer(buffer, sampleRate), which renders an AudioBuffer at another rate via OfflineAudioContext. Returns the input unchanged when rates match; rejects for unsupported rates.

SamplePlayer requires buffers at the context's sample rate, so consumers (e.g. hljod-smali's sample-rate switch) can use this instead of their own conversion code. Loading behavior is unchanged.

Summary by CodeRabbit

• New Features
  • Added audio resampling so audio buffers can be converted to a requested sample rate, including to match a playback context. Buffers already at the requested rate remain unchanged. Unsupported sample rates are rejected.

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📥 Commits

Reviewing files that changed from the base of the PR and between 6afd27b and 894c006.

📒 Files selected for processing (4)

• .changeset/resample-audio-buffer.md
• src/index.ts
• src/utils/audiodata/convert/resampleAudioBuffer.browser.test.ts
• src/utils/audiodata/convert/resampleAudioBuffer.ts

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Walkthrough

The package adds and exports resampleAudioBuffer. The function returns the original buffer when its sample rate matches the requested rate. Otherwise, it renders the buffer at the requested rate through an OfflineAudioContext. Browser tests and a minor changeset are included.

Changes

Audio buffer resampling

Layer / File(s)	Summary
Resampling function and package API src/utils/audiodata/convert/resampleAudioBuffer.ts, src/index.ts, src/utils/audiodata/convert/resampleAudioBuffer.browser.test.ts, .changeset/resample-audio-buffer.md	Adds and exports resampleAudioBuffer. Browser tests check sample rate, length, channel count, a sample value, and rejection for target rate 0. The changeset describes the function and its use case.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Feature

Merge Risk: ⚪ Minimal · up to 894c0

The new resampling utility appears ready to merge after normal checks.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly and concisely identifies the main change: adding the resampleAudioBuffer utility.
Docstring Coverage	✅ Passed	Docstring coverage is 100.00% which is sufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 1 functions across 3 files. (1 skipped: 1 …
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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[qodo-code-review]

PR Summary by Qodo

Add a public AudioBuffer resampling utility

✨ Enhancement 🧪 Tests 🕐 10-20 Minutes

AI Description

• Export a reusable way to match an AudioBuffer to a target sample rate before loading it into
 SamplePlayer.
• Preserve duration and channels during conversion; return matching-rate buffers unchanged and
 reject unsupported rates.
• Add browser tests and a minor-release changeset without changing SamplePlayer loading behavior.

Diagram

graph TD
  C["Consumer"] --> U["Resampling utility"] --> R{"Rates match?"} -->|Yes| I["Original buffer"] --> P["SamplePlayer"]
  R -->|No| O["Offline rendering"] --> B["Resampled buffer"] --> P

Loading

High-Level Assessment

Keep resampling explicit and reusable rather than adding it to SamplePlayer.loadLayers: this serves other AudioBuffer consumers while preserving the loader's current sample-rate checks.

Files changed (4) +49 / -0

Enhancement (2) +23 / -0

index.tsExport resampleAudioBuffer from the package +1/-0

Export resampleAudioBuffer from the package

• Makes the new utility available through the package's main entry point.

src/index.ts

resampleAudioBuffer.tsRender AudioBuffers at a requested sample rate +22/-0

Render AudioBuffers at a requested sample rate

• Adds an async utility that returns matching-rate buffers unchanged or renders them through OfflineAudioContext. It preserves channel count and rounds the target duration to whole frames.

src/utils/audiodata/convert/resampleAudioBuffer.ts

Tests (1) +21 / -0

resampleAudioBuffer.browser.test.tsTest browser-based buffer resampling +21/-0

Test browser-based buffer resampling

• Checks the output rate, length, channel count, and sample value after conversion. Also checks rejection of an unsupported target rate.

src/utils/audiodata/convert/resampleAudioBuffer.browser.test.ts

Other (1) +5 / -0

resample-audio-buffer.mdDeclare a minor release for the new utility +5/-0

Declare a minor release for the new utility

• Adds a minor changeset for @kidlib/web-audio and describes resampling buffers before SamplePlayer.loadLayers.

.changeset/resample-audio-buffer.md