# nvidia.dali.fn.to_decibels¶

nvidia.dali.fn.to_decibels(*inputs, **kwargs)

Converts a magnitude (real, positive) to the decibel scale.

Conversion is done according to the following formula:

min_ratio = pow(10, cutoff_db / multiplier)
out[i] = multiplier * log10( max(min_ratio, input[i] / reference) )

Supported backends
• ‘cpu’

• ‘gpu’

Parameters

input (TensorList) – Input to the operator.

Keyword Arguments
• bytes_per_sample_hint (int or list of int, optional, default = [0]) –

Output size hint, in bytes per sample.

If specified, the operator’s outputs residing in GPU or page-locked host memory will be preallocated to accommodate a batch of samples of this size.

• cutoff_db (float, optional, default = -200.0) –

Minimum or cut-off ratio in dB.

Any value below this value will saturate. For example, a value of cutoff_db=-80 corresponds to a minimum ratio of 1e-8.

• multiplier (float, optional, default = 10.0) – Factor by which the logarithm is multiplied. The value is typically 10.0 or 20.0, which depends on whether the magnitude is squared.

• preserve (bool, optional, default = False) – Prevents the operator from being removed from the graph even if its outputs are not used.

• reference (float, optional, default = 0.0) –

Reference magnitude.

If a value is not provided, the maximum value for the input will be used as reference.

Note

The maximum of the input will be calculated on a per-sample basis.

• seed (int, optional, default = -1) –

Random seed.

If not provided, it will be populated based on the global seed of the pipeline.