1€ filter

Provides a python implementation for the 1€ filter.

Install

pip install OneEuroFilter --upgrade

Minimal example

from OneEuroFilter import OneEuroFilter

config = {
    'freq': 120,       # Hz
    'mincutoff': 1.0,  # Hz
    'beta': 0.1,       
    'dcutoff': 1.0    
    }

f = OneEuroFilter(**config)

# First parameter is the value to filter
# the second parameter is the current timestamp in seconds
filtered = f(2.1, 0)

Doc

class OneEuroFilter.OneEuroFilter.OneEuroFilter(freq: float, mincutoff: float = 1.0, beta: float = 0.0, dcutoff: float = 1.0)

Bases: object

filter(x: float, timestamp: float = None)

Filters a noisy value.

• Parameters:
  • x (float) – Noisy value to filter.
  • timestamp (float*,* optional) – timestamp in seconds.
• Returns: the filtered value
• Return type: float

reset()

Resets the internal state of the filter.

setBeta(beta: float)

Sets the Beta parameter.

• Parameters: beta (float) – Parameter to reduce latency (> 0).

setDerivateCutoff(dcutoff: float)

Sets the dcutoff parameter.

• Parameters: dcutoff (float) – Used to filter the derivates. 1 Hz by default. Change this parameter if you know what you are doing.

setFrequency(freq: float)

Sets the frequency of the input signal.

• Parameters: freq (float) – An estimate of the frequency in Hz of the signal (> 0), if timestamps are not available.
• Raises: ValueError – If one of the frequency is not >0

setMinCutoff(mincutoff: float)

Sets the filter min cutoff frequency.

• Parameters: mincutoff (float) – Min cutoff frequency in Hz (> 0). Lower values allow to remove more jitter.
• Raises: ValueError – If one of the frequency is not >0

setParameters(freq: float, mincutoff: float = 1.0, beta: float = 0.0, dcutoff=1.0)

Sets all the parameters of the filter.

• Parameters:
  • freq (float) – An estimate of the frequency in Hz of the signal (> 0), if timestamps are not available.
  • mincutoff (float*,* optional) – Min cutoff frequency in Hz (> 0). Lower values allow to remove more jitter.
  • beta (float*,* optional) – Parameter to reduce latency (> 0).
  • dcutoff (float*,* optional) – Used to filter the derivates. 1 Hz by default. Change this parameter if you know what you are doing.
• Raises: ValueError – If one of the parameters is not >0

Related publication

@inproceedings{10.1145/2207676.2208639,
    author = {Casiez, G\'{e}ry and Roussel, Nicolas and Vogel, Daniel},
    title = {1 € Filter: A Simple Speed-Based Low-Pass Filter for Noisy Input in Interactive Systems},
    year = {2012},
    isbn = {9781450310154},
    publisher = {Association for Computing Machinery},
    address = {New York, NY, USA},
    url = {https://doi.org/10.1145/2207676.2208639},
    doi = {10.1145/2207676.2208639},
    pages = {2527–2530},
    numpages = {4},
    keywords = {noise, jitter, lag, precision, filtering, responsiveness, signal},
    location = {Austin, Texas, USA},
    series = {CHI '12}
}