Signal-to-Noise Ratio (SNR)¶

Module Interface¶

class torchmetrics.SignalNoiseRatio(zero_mean=False, **kwargs)[source]

Calculates Signal-to-noise ratio (SNR) meric for evaluating quality of audio. It is defined as:

$\text{SNR} = \frac{P_{signal}}{P_{noise}}$

where $P$ denotes the power of each signal. The SNR metric compares the level of the desired signal to the level of background noise. Therefore, a high value of SNR means that the audio is clear.

As input to forward and update the metric accepts the following input

preds (Tensor): float tensor with shape (...,time)
target (Tensor): float tensor with shape (...,time)

As output of forward and compute the metric returns the following output

snr (Tensor): float scalar tensor with average SNR value over samples

Parameters

zero_mean¶ (bool) – if to zero mean target and preds or not
kwargs¶ (Any) – Additional keyword arguments, see Advanced metric settings for more info.

Raises

TypeError – if target and preds have a different shape

Example

>>> import torch
>>> from torchmetrics import SignalNoiseRatio
>>> target = torch.tensor([3.0, -0.5, 2.0, 7.0])
>>> preds = torch.tensor([2.5, 0.0, 2.0, 8.0])
>>> snr = SignalNoiseRatio()
>>> snr(preds, target)
tensor(16.1805)

Initializes internal Module state, shared by both nn.Module and ScriptModule.

Functional Interface¶

torchmetrics.functional.signal_noise_ratio(preds, target, zero_mean=False)[source]

Calculates Signal-to-noise ratio (SNR) meric for evaluating quality of audio. It is defined as:

$\text{SNR} = \frac{P_{signal}}{P_{noise}}$

where $P$ denotes the power of each signal. The SNR metric compares the level of the desired signal to the level of background noise. Therefore, a high value of SNR means that the audio is clear.

Parameters

preds¶ (Tensor) – float tensor with shape (...,time)
target¶ (Tensor) – float tensor with shape (...,time)
zero_mean¶ (bool) – if to zero mean target and preds or not

Return type

Tensor

Returns

Float tensor with shape (...,) of SNR values per sample

Raises

RuntimeError – If preds and target does not have the same shape

Example

>>> from torchmetrics.functional.audio import signal_noise_ratio
>>> target = torch.tensor([3.0, -0.5, 2.0, 7.0])
>>> preds = torch.tensor([2.5, 0.0, 2.0, 8.0])
>>> signal_noise_ratio(preds, target)
tensor(16.1805)