🎵 True Peak Adjuster

Professional Audio True Peak Adjustment Tool

📋 Overview

True Peak Adjuster is a professional tool that accurately adjusts the True Peak of audio files to -0.1 dBTP. It uses FFmpeg's EBU R128 filter to perform industry-standard compliant True Peak measurement and adjustment.

Key Features

  • Accurate True Peak measurement with FFmpeg EBU R128
  • Support for WAV, FLAC, and ALAC (M4A) formats
  • Complete preservation of metadata and cover art
  • Simple drag-and-drop operation
  • Batch processing of multiple files and folders
  • Support for all sample rates and bit depths

💻 System Requirements

Item Requirement
Operating System Windows 10 / Windows 11
Required Software FFmpeg (added to system PATH)
Supported Formats WAV (.wav), FLAC (.flac), ALAC (.m4a)
Sample Rate 8kHz ~ 384kHz (all supported)
Bit Depth 16bit, 24bit, 32bit, 32bit float, 64bit float

🔧 Installation

1Installing FFmpeg

FFmpeg is required. Follow these steps to install:

  1. Download "ffmpeg-release-essentials.zip" from https://www.gyan.dev/ffmpeg/builds/
  2. Extract the ZIP file (e.g., to C:\ffmpeg)
  3. Add to system environment variable PATH (e.g., C:\ffmpeg\bin)
  4. Verify installation by running ffmpeg -version in Command Prompt
💡 Tip: After installing FFmpeg, restart your computer to apply the PATH settings.

2Placing True Peak Adjuster

Simply place TruePeakAdjuster.exe in any folder to use it.

📖 How to Use

Basic Usage

  1. Double-click TruePeakAdjuster.exe to display usage instructions
  2. Drag and drop audio files or folders onto TruePeakAdjuster.exe
  3. Wait for processing to complete
  4. Output files with "_TP" suffix will be saved in the same location as original files

Supported Operations

  • Single file drop → Process that file
  • Multiple files drop → Process all files
  • Folder drop → Process all supported files directly in the folder
⚠️ Note: When dropping a folder, files in subfolders will not be processed. Only files directly in the folder will be processed.

Output File Names

Processed files have "_TP" suffix added to the original file name:

Examples:
song.wav → song_TP.wav
album.flac → album_TP.flac
track.m4a → track_TP.m4a

🎯 Technical Specifications

True Peak Measurement

Uses FFmpeg's ebur128 filter to perform accurate True Peak measurement compliant with EBU R128 standards. This method detects inter-sample peaks, making it more accurate than traditional sample peak measurement.

Target True Peak Value

Default: -0.1 dBTP

This value is set to ensure maximum loudness while preventing digital clipping.

Metadata Preservation

Format Preserved Metadata
WAV ID3v2.3 tags + Cover art
FLAC Vorbis Comment tags + Cover art (Picture)
ALAC MP4 metadata + Cover art

Processing Flow

  1. Measure current True Peak with FFmpeg ebur128 filter
  2. Calculate linear gain from difference with target value (-0.1 dBTP)
  3. Apply gain to audio data
  4. Verify True Peak of processed audio
  5. Copy metadata and cover art from original file
  6. Save output file

📊 Processing Examples

Case 1: High True Peak

Current True Peak: 0.50 dBTP
Required Gain: -0.60 dB (Linear: 0.933254)
New True Peak: -0.10 dBTP

→ Reduce volume to adjust to -0.1 dBTP

Case 2: Low True Peak

Current True Peak: -0.50 dBTP
Required Gain: 0.40 dB (Linear: 1.047129)
New True Peak: -0.10 dBTP

→ Increase volume to adjust to -0.1 dBTP

Case 3: Already at Target Value

Current True Peak: -0.10 dBTP
Required Gain: 0.00 dB (Linear: 1.000000)
New True Peak: -0.10 dBTP

→ No gain adjustment (metadata only copied)

❓ Troubleshooting

"FFmpeg is not available" Error

FFmpeg is not added to system PATH. Please check the following:

  1. Is FFmpeg installed correctly?
  2. Is FFmpeg's bin folder added to system environment variable PATH?
  3. Have you restarted your computer?

Metadata Not Preserved

The original file may not contain metadata. Please check the processed file with a media player.

Processing is Slow

FFmpeg ebur128 measurement takes time as it analyzes the entire file. Processing time will be longer especially for long-duration audio files or high-resolution audio.

⚠️ Important Notes

  • Original files are not modified (new files are created)
  • Existing files with "_TP" suffix will be overwritten
  • True Peak adjustment does not affect sound quality (linear gain only)
  • If extreme gain changes are required, please check the original source

📝 Version History

Version Date Changes
1.0.0 2025-11-26 Initial release

📄 License

This software is free to use for both personal and commercial purposes.

Libraries Used:
  • Python 3.x
  • NumPy
  • soundfile
  • mutagen
  • FFmpeg

True Peak Adjuster v1.0.0

© 2025 All Rights Reserved