Zero-dependency C++17 dynamic range meter. The name is French for peak / crest — the origin of the audio term crest factor.

Measures TT Dynamic Range (Pleasurize Music Foundation algorithm), EBU R128 integrated loudness, true peak (4× polyphase FIR), PLR, PSR, LRA, crest factor, and per-channel variants for lossless audio files. PCM output is compatible with dr.loudness-war.info submission format; DSD output uses the same algorithmic conventions as foobar2000's SACD plugin in Direct mode.

make                    # optimized build, no JSON output
make VERSION=0.6.3      # custom version stamp
make debug              # debug build with sanitizers
make install            # install to /usr/local/bin

Single translation unit (main.cpp), no external libraries.

make cli-json           # auto-fetches nlohmann/json header into third_party/

Adds the -f json output mode for machine-readable analysis. The header is downloaded on first build; subsequent builds are offline. The CLI remains a single binary.

# Install dependencies
sudo dnf install SDL2-devel mesa-libGL-devel    # Fedora
sudo apt install libsdl2-dev libgl-dev          # Ubuntu
brew install sdl2                               # macOS

# Get Dear ImGui (one-time)
make setup-imgui

# Build
make gui                # GUI app
make all                # cli-json + gui together
make debug-gui          # GUI with sanitizers

The GUI binary is crete-gui. It supports drag-and-drop, native file/folder dialogs, sortable results, color-coded DR values, and saves a log next to the analysed folder.

crete --version
crete /path/to/album/
crete -f foobar /path/to/album/
crete -f ext /path/to/album/
crete -f detail /path/to/album/
crete -f json /path/to/album/    # cli-json builds only
crete -o dr_log.txt /path/to/album/
crete -q /path/to/album/         # suppress progress, useful in CI

crete-gui

Browse for a file or folder (or drag-and-drop), pick an output format, click Analyze.

When a folder contains a .cue file, crête:

1. Parses the cue (FILE, TRACK, TITLE, PERFORMER, INDEX 01).
2. Locates the referenced audio file (case-insensitive fallback).
3. Decodes that file once, then slices its PCM by track boundaries and runs the full analysis pipeline on each slice.

Each track is reported as NN - Title.ext (e.g. 01 - What A Shame.dff), matching the per-track naming convention produced by sacd_extract, flac --split, and most other splitters — so a cue-sliced monolithic album pairs cleanly against the equivalent per-track album. Audio files in the same folder not referenced by any cue are still analysed individually.

This makes SACD rips (one big .dff + cue), CD images (one big .flac + cue), and vinyl rips work without any preprocessing.

Track times are stored internally as CDDA frames (1/75 sec) and converted to PCM samples at the actual decoded rate, so the same cue works for 44.1 kHz WAV and 352.8 kHz DSD-decoded PCM without rounding loss (every standard rate is divisible by 75).

Memory note. A monolithic 60-minute DSD64 album decodes to ~21 GB of float64 PCM at 352.8 kHz before slicing. Cue-sliced analysis adds one slice (~1.7 GB) and the analyser's working set (~2× the slice) on top. Plan accordingly on memory-constrained hosts.

ALAC (.m4a): requires MP4/ISO BMFF container parsing. Convert first: ffmpeg -i input.m4a -c:a flac output.flac.

Official Album Data reference: https://dr.loudness-war.info/album/view/200279

dr.loudness-war.info–compatible:

----------------------------------------------------------------------------------------------
 Analyzed Folder: /home/abalaji/Music/Random Access Memories/Disc 2
----------------------------------------------------------------------------------------------
DR         Peak       RMS        Filename
----------------------------------------------------------------------------------------------

DR11       -1.77 dB   -17.31 dB  01. Horizon Ouverture - Daft Punk.wav
DR10       -0.01 dB   -12.91 dB  02. Horizon (Japan CD) - Daft Punk.wav
DR9        over       -10.56 dB  03. GLBTM (Studio Outtakes) - Daft Punk.wav
DR7        -0.09 dB    -8.09 dB  04. Infinity Repeating (2013 Demo) - Daft Punk.wav
...
----------------------------------------------------------------------------------------------

 Number of Files: 9
 Official DR Value: DR9

==============================================================================================

Mimics foobar2000 DR Meter 1.1.1 output, with duration and per-album technical info block:

crête 0.6.3 / TT DR Offline Meter
log date: 2026-05-29 06:59:00

--------------------------------------------------------------------------------
Analyzed: Random Access Memories / Disc 2
--------------------------------------------------------------------------------

DR         Peak         RMS     Duration Track
--------------------------------------------------------------------------------
DR11        -1.77 dB   -17.31 dB     2:08 01. Horizon Ouverture - Daft Punk
DR10        -0.01 dB   -12.91 dB     4:22 02. Horizon (Japan CD) - Daft Punk
...
--------------------------------------------------------------------------------

Number of tracks:  9
Official DR value: DR9

Samplerate:        44100 Hz
Channels:          2
Bits per sample:   16
Codec:             WAV
================================================================================

MAAT DROffline MkII–style pipe-delimited table. Twenty-six columns: per-channel sample peaks and true peaks, RMS, max momentary and short-term LUFS, LUFSi, DR (PMF), DR LEFT, DR RIGHT, PLR, LRA, Min PSR, and more. Ideal for parity testing against MAAT reference logs.

Per-track block view with all per-channel metrics in a vertical table — easier to read for single-track investigation than the wide ext format.

Machine-readable output with every metric for every track, including the full per-channel channel_metrics array. Used by the pytest CI harness to compare against reference databases without scraping text output.

{
  "version": "crête 0.6.3",
  "folder_path": "/home/abalaji/Music/Random Access Memories/Disc 2",
  "album_dr": 9,
  "num_tracks": 9,
  "sample_rate": 44100,
  "channels": 2,
  "bit_depth": 16,
  "codec": "WAV",
  "tracks": [
    {
      "filename": "01. Horizon Ouverture - Daft Punk.wav",
      "dr_score": 11,
      "dr_raw": 11.24,
      "peak_dbfs": -1.77,
      "rms_dbfs": -17.31,
      "integrated_lufs": -20.3,
      "max_true_peak_dbtp": -1.65,
      "plr_db": 18.6,
      "lra_lu": 4.2,
      "psr_db": 12.8,
      "channel_metrics": [
        { "label": "Left",  "sample_peak_dbfs": -1.77, "rms_dbfs": -17.42, ... },
        { "label": "Right", "sample_peak_dbfs": -1.81, "rms_dbfs": -17.20, ... }
      ],
      ...
    },
    ...
  ]
}

1. Split audio into 3-second non-overlapping blocks.
2. Compute RMS (power-summed across channels) and peak per block.
3. Discard silent blocks (joint RMS < −60 dBFS).
4. Sort blocks by RMS, descending.
5. Select the top 20 % loudest blocks (floor(0.2 · N)).
6. DR = 20 · log₁₀(2nd-highest block peak / mean of top-20 % RMS).
7. Round to integer.

The 2nd-highest peak (rather than the highest) follows the foobar2000 DR Meter v0.2 changelog and matches MAAT DROffline behavior on most material.

K-weighting (BS.1770-4) implemented via hardcoded biquad coefficients from libebur128, with absolute gating at −70 LUFS and relative gating at −10 LU below the ungated mean. 400 ms momentary blocks at 75 % overlap; 3 s short-term blocks at 67 % overlap.

4× polyphase FIR (12 taps per phase) per channel; joint result is the max across channels.

PLR uses min(max_true_peak, 0) − LUFSi to match MAAT's clamp behavior on over-full-scale material. PSR is computed per 3-second short-term window with a −50 LUFS floor and reported as the minimum. LRA follows BS.1770-4 with linear-interpolated 95th/10th percentile after relative gating at −20 LU.

DSD bitstreams are decimated to 352.8 kHz PCM using foobar2000 SACD plugin's fir1_8 (DSD64, 80 taps) or fir1_16 (DSD128, 160 taps) coefficients, normalized to unity DC gain. This matches foobar's Direct-mode output exactly — peaks are bit-accurate against foobar references. The Multistage 384 kHz mode is not supported (planned for v1.1, see CRETE_TODO.md).

A byte-LUT polyphase engine (dsd_lut.hpp) replaces per-bit FIR convolution with precomputed 256-entry lookup tables — roughly 8× faster than the naive implementation, with one thread per channel.

main.cpp          CLI entry point, output formatters, cue-aware grouping
gui_main.cpp      GUI entry point (Dear ImGui + SDL2 + OpenGL)
analysis.hpp      TT DR, EBU R128, true peak, PLR/PSR/LRA, crest factor
audio.hpp         WAV, AIFF/AIFF-C, FLAC, DSF, DFF decoders
dsd_lut.hpp       Byte-LUT polyphase FIR engine for DSD → PCM decimation
cue.hpp           Zero-dependency cue sheet parser
file_dialog.hpp   Portable native file/folder dialogs (Linux/macOS/Windows)
Makefile          Build system (cli / cli-json / gui / all)
third_party/      Dear ImGui, nlohmann/json (fetched on demand)

The analysis.hpp and audio.hpp files are deliberately monolithic — single-translation-unit builds keep the CLI dependency-free and the build trivially reproducible across distros.

MIT License — Ashwin Balaji 2026.

DSD decimation coefficients (fir1_8, fir1_16 in dsd_lut.hpp) are derived from Maxim V. Anisiutkin's foobar2000 SACD plugin and are used under LGPL 2.1.