NKI Tool

A utility for extracting data from Native Instruments Kontakt (.nki) files.

Features

This tool can extract:

• XML metadata from Kontakt instrument files
• WAV samples embedded in the NKI file (both uncompressed PCM and compressed formats)
• Original filenames and MIDI note mapping information from the NKI file
• Enhanced SFZ instrument files for use in SFZ-compatible samplers with proper note mapping

What's New in Version 2.0 (2024-03-23)

• Original filenames are now extracted from NKI's internal listing
• Prefix cleanup to remove unnecessary path components and prefixes
• Directory structure is created to match the original instrument
• Enhanced SFZ files with accurate note mapping and proper filenames
• Improved filename parsing for better organization

Supported Formats

• Kontakt 1-4
• WAV Audio: Detects and handles both raw PCM and compressed formats
• Preserves original filename patterns including note numbers and names

Usage

./nki <filename.nki>

This will create the following output files:

• <filename.nki>.xml: XML metadata from the instrument
• A folder named after the instrument containing all extracted samples
• Sample files with their original names, cleaned up and with note information preserved
• <filename.nki>.sfz: Enhanced SFZ format instrument definition with proper mapping

Building from Source

make clean && make

The tool uses the system zlib library. Make sure zlib development files are installed on your system.

• On macOS: Usually pre-installed
• On Ubuntu/Debian: sudo apt-get install zlib1g-dev
• On Fedora/RHEL/CentOS: sudo dnf install zlib-devel

Extractable Data

Sample Extraction and Filename Handling

The tool automatically:

• Identifies and extracts WAV samples embedded in the NKI file
• Finds original filenames from the NKI's internal listing
• Cleans up filenames by removing unnecessary path components and prefixes
• Preserves MIDI note numbers and names in the filename patterns
• Creates a directory structure that matches the original instrument

The filename pattern for extracted samples is:

[Instrument Name]-000-[MIDI Note]-[Note Name].wav

For example:

DW8000 Funk Long-000-048-c2.wav
DW8000 Funk Long-000-051-d#2.wav
DW8000 Funk Long-000-054-f#2.wav

SFZ Files

The tool automatically generates enhanced SFZ files that include:

• Proper sample mapping based on extracted MIDI note information
• Key ranges for each sample with intelligent boundary calculation
• Crossfades between sample boundaries for smooth playback
• Velocity sensitivity appropriate for the instrument type
• Release sample handling (if release samples are present)

Note Mapping Information

The key mapping information is now extracted directly from the original sample names, providing:

• Accurate root notes for each sample
• Intelligently calculated key ranges
• Proper pitch mapping in the SFZ file

Requirements

• Standard C compiler (clang or gcc)
• System zlib library (zlib1g-dev on Debian/Ubuntu, zlib-devel on RHEL/CentOS)

Limitations

• Cannot extract samples that are referenced but stored externally
• Some complex NKI files may have samples that cannot be extracted
• Not all NKI versions or formats are fully supported
• No support for importing XML back into NKI files

Original Project

http://www.linuxsampler.org/nkitool/