stretch

Time-stretch and pitch-shift audio files offline with configurable quality settings.

1|Updated Jul 11, 2026

Search Tags:#audio processing #DSP #audio engineering #time-stretching #pitch shifting

Ready to run

npx skills add https://github.com/danielraffel/burl --skill stretch

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: stretch
Source: https://github.com/danielraffel/burl/tree/main/.agents/skills/stretch
Command: npx skills add https://github.com/danielraffel/burl --skill stretch

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill requires build/examples/offline-stretch/stretchcli, and includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill provides offline time-stretching and pitch shifting capabilities, enabling agents to process audio with high-quality results and fine-tuned control.

Core Features & Use Cases

Offline Time-Stretching: Adjust the duration of audio without altering the pitch, with options for character modes and quality settings.
Pitch Shifting: Change the pitch of audio while preserving the timing, suitable for creating different versions of songs or sound effects.
Use Case: An agent might use this Skill to create a looped version of a song by stretching the audio, or to adjust the pitch of a sound effect for a specific project.

Quick Start

Use the stretch skill to time-stretch the audio file 'song.mp3' to half its original duration with high quality.

Frequently Asked Questions about stretch

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I time-stretch an audio file without changing its pitch?▼

Offline time-stretching adjusts audio duration without altering pitch by using character modes and quality settings to process files with fine-tuned control.

Can I shift the pitch of a sound effect while preserving the original timing?▼

Pitch shifting changes audio pitch while preserving timing, allowing you to create different versions of songs or sound effects for specific projects.

Do I need a specific build environment for offline audio time-stretching?▼

Offline time-stretching requires a build environment with specific CMake configurations and access to the stretchcli tool to process audio files correctly.

What is the best way to stretch a song to half its original duration?▼

Use offline time-stretching with high-quality settings to adjust the song to half its original duration, creating looped versions or matching specific length requirements.

What character modes are available for audio time-stretching?▼

Audio time-stretching supports character modes that define different stretching behaviors, along with quality adjustments to control the final audio output characteristics.