A Python toolkit for extracting, filtering, synchronizing, and resampling multi-modal data streams from XDF (Extensible Data Format) files, plus utilities for survey data cleanup.
- 🔍 Robust name matching - Case-insensitive and whitespace-tolerant stream/channel selection
- 🔄 Multi-stream synchronization - Align streams with different sampling rates
- ⚡ Flexible resampling - Interpolate data to any target frequency
- ✂️ Edge truncation - Remove unstable data from recording boundaries
- 🛠️ Diagnostic tools - Debug stream selection issues easily
- 📊 All-in-one pipeline - Process everything with a single function call
- 🧹 Automatic cleanup - Remove invalid entries and format inconsistencies
- 🔢 Smart type conversion - Handle numeric fields with commas and special characters
- 📅 Year-to-experience conversion - Automatically convert birth years to experience values
- ✅ Data validation - Filter out non-numeric participant IDs
pip install pandas numpy scipy pyxdfThen download xdf_stream_processing.py and place it in your project directory.
import pyxdf
from xdf_stream_processing import process_xdf_streams, print_stream_info
# Load your XDF file
streams, header = pyxdf.load_xdf("recording.xdf")
# Inspect available streams
print_stream_info(streams)
# Define what you want to extract
selection = {
"VarjoEyeMetrics": ["leftPupilDiam", "rightPupilDiam"],
"Polar H10": ["HR", "RRI"],
}
# Process everything in one call
df = process_xdf_streams(
streams=streams,
selection_dict=selection,
target_freq=50.0, # Resample to 50 Hz
truncate_n=100, # Remove 100 samples from each end
verbose=True
)
# Save your processed data
df.to_csv("processed_data.csv", index=False)from xdf_stream_processing import print_stream_info, get_copyable_format
# See all available streams and channels
print_stream_info(streams)
# Get a copyable template for selection_dict
get_copyable_format(streams)The main function handles everything:
df = process_xdf_streams(
streams=streams, # From pyxdf.load_xdf()
selection_dict=selection, # What to extract
target_freq=50.0, # Target sampling rate (Hz)
truncate_n=100, # Edge samples to remove
verbose=True # Show progress
)For more control, use individual functions:
from xdf_stream_processing import (
select_streams_by_name,
streams_to_dataframe,
resample_dataframe,
truncate_dataframe
)
# Step-by-step processing
selected = select_streams_by_name(streams, selection)
df = streams_to_dataframe(selected, target_freq=50.0)
df = resample_dataframe(df, target_freq=100.0)
df = truncate_dataframe(df, n=50)The toolkit includes utilities for cleaning survey data, particularly useful for preprocessing questionnaire responses before analysis.
- Participant ID cleanup: Remove special characters (e.g., '#5' → '5')
- Invalid entry filtering: Remove non-numeric participant IDs (e.g., rows starting with letters)
- Numeric field cleaning: Remove commas from numeric fields (e.g., '1,000' → '1000')
- Smart year conversion: Convert year values to experience (e.g., '1995' → '30' for experience)
import pandas as pd
# Load your survey data
survey_data = pd.read_csv("raw_survey.csv")
# Make a proper copy to avoid warnings
selected_data = survey_data.copy()
# Clean participant IDs - remove '#' prefix
selected_data['pid'] = selected_data['pid'].astype(str).str.replace('#', '', regex=False)
# Filter out invalid participant IDs (keep only numeric)
selected_data = selected_data[selected_data['pid'].str.match(r'^\d', na=False)].copy()
# Remove commas from numeric fields (e.g., flight hours)
selected_data['flt_hrs'] = selected_data['flt_hrs'].astype(str).str.replace(',', '', regex=False)
# Clean experience column with smart year detection
def clean_experience(val):
try:
num = float(val.replace(',', ''))
if num >= 1900: # Likely a year, convert to experience
return str(int(2025 - num))
else: # Already an experience value
return str(int(num))
except:
return val # Keep original if conversion fails
selected_data['experience'] = selected_data['experience'].astype(str).apply(clean_experience)
# Save cleaned data
clean_survey_data = selected_data.copy()
clean_survey_data.to_csv('clean_survey_data.csv', index=False)
print(f"Cleaned {len(clean_survey_data)} survey responses")-
Remove special characters from IDs
df['pid'] = df['pid'].astype(str).str.replace('#', '', regex=False)
-
Filter invalid entries
df = df[df['pid'].str.match(r'^\d', na=False)].copy()
-
Clean numeric fields
df['numeric_field'] = df['numeric_field'].astype(str).str.replace(',', '', regex=False)
-
Convert years to age/experience
def year_to_experience(val, current_year=2025): try: num = float(val.replace(',', '')) if num >= 1900: return str(int(current_year - num)) return str(int(num)) except: return val df['experience'] = df['experience'].astype(str).apply(year_to_experience)
After cleaning, always verify your data:
print(f"Shape after cleaning: {clean_survey_data.shape}")
print(f"\nUnique participant IDs: {clean_survey_data['pid'].nunique()}")
print(f"\nCleaned experience values:\n{clean_survey_data['experience'].value_counts()}")| Parameter | Description | Default |
|---|---|---|
target_freq |
Target sampling frequency in Hz | 50.0 |
truncate_n |
Samples to remove from each end | 0 |
verbose |
Print detailed progress information | True |
use_timestamps |
Use original timestamps vs synthetic | True |
The selection_dict maps stream names to lists of channel names:
selection_dict = {
"StreamName1": ["channel1", "channel2", "channel3"],
"StreamName2": ["channelA", "channelB"],
# Add more streams as needed
}Features:
- ✅ Case-insensitive matching
- ✅ Whitespace-tolerant
- ✅ Partial matches allowed (extracts available channels)
- ✅ Special handling for Polar H10 devices
The processed DataFrame contains:
Timecolumn: Common time base in seconds{StreamName}_{ChannelName}columns: One per selected channel
Example:
Time VarjoEyeMetrics_leftPupilDiam VarjoEyeMetrics_rightPupilDiam Polar H10_HR
0 0.000 3.245 3.156 72.3
1 0.020 3.248 3.159 72.3
2 0.040 3.251 3.162 72.4
...
df = process_xdf_streams(streams, selection, target_freq=250.0)df = process_xdf_streams(streams, selection, target_freq=10.0)df = streams_to_dataframe(streams, resample=False)df = process_xdf_streams(streams, selection, truncate_n=200)# Remove test entries and format fields
survey = survey[survey['pid'].str.match(r'^\d', na=False)].copy()
survey['flt_hrs'] = survey['flt_hrs'].str.replace(',', '')# Convert all numeric fields to proper types
numeric_cols = ['flt_hrs', 'experience', 'age']
for col in numeric_cols:
survey[col] = pd.to_numeric(survey[col], errors='coerce')See example_usage.py for comprehensive examples including:
- Basic workflow with synthetic data
- Loading and processing real XDF files
- Custom processing workflows
- Diagnostic and debugging tools
- Multiple processing frequencies
- Survey data cleanup workflows
Run examples:
python example_usage.py| Function | Purpose |
|---|---|
process_xdf_streams() |
Complete pipeline (recommended) |
print_stream_info() |
Display available streams/channels |
get_copyable_format() |
Generate selection template |
select_streams_by_name() |
Filter streams and channels |
streams_to_dataframe() |
Synchronize and merge streams |
resample_dataframe() |
Resample to uniform frequency |
truncate_dataframe() |
Remove edge samples |
Survey data cleanup functions are provided as code snippets in the documentation above. For a complete implementation, see the examples directory.
- Python 3.7+
- pandas
- numpy
- scipy
- pyxdf (for loading XDF files)
If you use XDF Stream Selector in your research, please cite:
@software{xdf_stream_selector,
author = {Md Mijanur Rahman, Niklas P. Schulmeyer},
title = {XDF Stream Selector: A Python Toolkit for Multi-Modal Data Stream Processing},
year = {2025},
url = {https://github.com/aeon-lab/stream_selector},
version = {1.0.0}
}This project is licensed under the MIT License - see below for details.
MIT License
Copyright (c) 2025 [Your Name/Organization]
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
Md Mijanur Rahman
Niklas P. Schulmeyer
Contributions welcome! Please feel free to submit a Pull Request.