How it works
What the report reads
The container report lists what the file declares: format, duration, bitrate, and for each audio stream its codec, channel count and sample rate. Tags such as title, artist and cover art appear when the file has them.
The numbers above it come from the decoded samples, so they describe what you would actually hear.
Levels and loudness
Peak is the highest sample, RMS is the average power of all samples, both in dBFS where 0 is digital full scale. Integrated loudness follows ITU-R BS.1770-4: audio is K-weighted, cut into 400 ms blocks, quiet blocks are gated out, and the rest are averaged.
LUFS = −0.691 + 10 × log10(mean K-weighted power of gated blocks)
Waveform and spectrum
The waveform shows the loudest and quietest sample in each slice of time. The spectrum averages Hann-windowed 2048-sample FFT frames spread across the file, mixed to mono, and draws them from bass on the left to half the sample rate on the right, relative to the loudest band.
