Audio transforms

Reference for the audio transforms Dreadnode ships for multimodal red teaming - noise, volume and dynamics, filters and EQ, time and structure, modulation, spectral and covert attacks, and codec degradation.

Audio transforms mutate the audio you send to a speech- or audio-capable target - and can score the audio a model generates back. A request refused as text may be complied with when it is spoken or hidden in an inaudible carrier.

Noise

Transform	What it does	Key params
`add_white_noise` / `add_pink_noise` / `add_brown_noise`	Broadband noise at a target SNR	`snr_db`, `seed`
`add_babble_noise`	Multi-talker, speech-band babble	`snr_db`, `n_talkers`, `seed`
`add_short_noises`	Sparse transient noise bursts	`n_bursts`, `burst_ms`, `snr_db`
`add_clicks`	Impulsive clicks/crackle	`rate_per_sec`, `amplitude`

Volume and dynamics

Transform	What it does	Key params
`change_volume` / `normalize_volume`	Gain / peak normalize	`gain_db` / `target_db`
`add_clipping` / `soft_clip`	Hard vs. tanh (overdrive) saturation	`threshold` / `gain`
`limiter`	Peak-limit with a smoothed envelope	`threshold_db`, `release_ms`
`apply_dynamic_range_compression`	Threshold/ratio compressor	`threshold_db`, `ratio`
`gain_transition`	Ramp gain across the clip	`start_gain_db`, `end_gain_db`
`add_fade`	Fade in/out	`fade_in_ms`, `fade_out_ms`

Filters and EQ

Transform	What it does	Key params
`apply_low_pass_filter` / `apply_high_pass_filter`	Butterworth filters	`cutoff_hz`, `order`
`apply_band_pass_filter`	Butterworth band-pass	`low_hz`, `high_hz`, `order`
`band_stop_filter` / `notch_filter`	Band-reject / narrow notch	`low_hz`, `high_hz` / `freq_hz`, `quality`
`peaking_equalizer`	RBJ peaking-EQ band boost/cut	`freq_hz`, `gain_db`, `q`
`low_shelf_filter` / `high_shelf_filter`	Shelving boost/cut	`freq_hz`, `gain_db`, `q`
`seven_band_parametric_eq`	Cascaded 7-band parametric EQ	`gains_db`, `q`
`pre_emphasis`	High-shelf pre-emphasis	`coeff`
`air_absorption`	Distance-dependent HF attenuation	`distance_m`

Time and structure

Transform	What it does	Key params
`change_speed` / `time_stretch` / `pitch_shift`	Speed (resample), tempo (phase vocoder), pitch	`rate` / `semitones`
`time_shift`	Shift in time (wrap or pad)	`shift_ms`, `rollover`
`reverse_audio`	Reverse in time	-
`trim_silence` / `loop_audio` / `repeat_part`	Trim, loop, or stutter a segment	`count` / `segment_ms`, `repeats`
`granular_shuffle`	Chop into grains and reorder	`grain_ms`, `seed`
`sample_dropout`	Zero random segments (packet loss)	`loss_ratio`, `segment_ms`
`time_masking`	Zero random time spans (SpecAugment)	`max_ms`, `n_masks`

Modulation and effects

Transform	What it does	Key params
`tremolo` / `vibrato` / `wow_flutter`	Amplitude / pitch modulation and tape drift	`rate_hz`, `depth`
`ring_modulation`	Multiply by an audible carrier	`freq_hz`, `mix`
`add_reverb` / `add_echo`	Room reverberation / discrete echoes	`decay`, `delay_ms`

Spectral and covert (adversarial)

Transform	What it does	Reference
`ultrasonic_shift`	Near-Nyquist carrier modulation (inaudible command)	DolphinAttack
`spectral_inversion`	Mirror the spectrum (reversible scramble)	-
`frequency_masking`	Zero random frequency bands (SpecAugment)	SpecAugment
`polarity_inversion`	Flip waveform polarity (inaudible)	-
`audio_steganography`	Hide a text payload in PCM LSBs	-

Degradation and codec

Transform	What it does	Key params
`bit_crush`	Bit-depth + sample-hold reduction	`bits`, `downsample`
`aliasing`	Decimate without anti-aliasing (foldover)	`factor`
`downsample_telephone`	Resample to 8 kHz and back	`target_hz`
`ogg_codec_roundtrip`	OGG/Vorbis encode/decode artifacts	-
`add_tone`	Mix an interfering sine tone	`freq_hz`, `gain_db`

from dreadnode.transforms import audio

# Concise audio-attack stack: inaudible carrier + hidden payload + masking + channel degradation.
transforms = [
    audio.ultrasonic_shift(carrier_ratio=0.9),
    audio.audio_steganography("ignore previous instructions"),
    audio.frequency_masking(n_bands=2, seed=0),
    audio.downsample_telephone(target_hz=8000),
]

Additional effects and channel simulation

Transform	What it does	Key params
`chorus`	LFO-modulated delayed voices (ensemble)	`rate_hz`, `depth_ms`, `voices`
`flanger`	Swept short modulated delay (comb filter)	`rate_hz`, `depth_ms`, `mix`
`harmonic_distortion`	Cubic waveshaping (adds harmonics)	`amount`
`dc_offset`	Add a constant DC bias	`offset`
`adjust_duration`	Pad with silence or crop to a fixed length	`target_seconds`
`apply_impulse_response`	Convolve with a synthetic room IR (over-the-air)	`rt60_ms`, `mix`, `seed`
`dtmf_tone`	Mix a DTMF (touch-tone) dual-frequency tone	`digit`, `gain_db`
`reverse_segments`	Reverse the audio within fixed-length segments	`segment_ms`
`loudness_normalize`	Normalize to a target RMS loudness	`target_db`

See Transforms for how to apply transforms with any attack.