Codec Changes Need Regression Tests
A successful transcode only proves that a decoder can open the result. It says nothing about lost attacks, collapsed width, spectral smearing, or accidental silence.
codecguard synthesizes a deterministic stereo master, runs a real FFmpeg encode and decode, aligns encoder priming, and evaluates four independent dimensions.
The Demo
The release candidate reaches 33.396 dB SNR, 0.02087 spectral convergence, 0.9954 transient retention, and 0.00025 stereo-width error, passing every gate. The degraded build fails all four.
Signal metrics make CI deterministic but do not replace perceptual codecs, formal listening panels, or content-diverse mastering review.
Implementation Basis
The gate combines multi-resolution frequency evidence with time-domain transients, stereo energy, and aligned waveform error.
Read the FFmpeg codec documentation.