Inspector Trace Set .trs file support in Python

Build Status Documentation Status

Riscure Inspector uses the .trs file format to save and read traces from disk. To better assist reading and writing trace set files from third parties, Riscure published this Python library.

Quick start

This library supports reading and writing of .trs files, but it does not (yet) support modifying existing .trs files. Both the TraceSet and the Trace class emulate all the functionality of a list, so slice to your heart’s content!

Installation

This library is available on PyPi for Python 3 and up. Just add trsfile to your requirements.txt or install it via the command line:

pip install trsfile

Reading .trs files

import trsfile

with trsfile.open('trace-set.trs', 'r') as traces:
    # Show all headers
    for header, value in traces.get_headers().items():
        print(header, '=', value)
    print()

    # Iterate over the first 25 traces
    for i, trace in enumerate(traces[0:25]):
        print('Trace {0:d} contains {1:d} samples'.format(i, len(trace)))
        print('  - minimum value in trace: {0:f}'.format(min(trace)))
        print('  - maximum value in trace: {0:f}'.format(max(trace)))

Creating .trs files

import random, os, trsfile
from trsfile import trs_open, Trace, SampleCoding, TracePadding, Header

with trs_open(
        'trace-set.trs',                 # File name of the trace set
        'w',                             # Mode: r, w, x, a (default to x)
        # Zero or more options can be passed (supported options depend on the storage engine)
        engine = 'TrsEngine',            # Optional: how the trace set is stored (defaults to TrsEngine)
        headers = {                      # Optional: headers (see Header class)
            Header.LABEL_X: 'Testing X',
            Header.LABEL_Y: 'Testing Y',
            Header.DESCRIPTION: 'Testing trace creation',
        },
        padding_mode = TracePadding.AUTO,# Optional: padding mode (defaults to TracePadding.AUTO)
        live_update = True               # Optional: updates the TRS file for live preview (small performance hit)
                                         #   0 (False): Disabled (default)
                                         #   1 (True) : TRS file updated after every trace
                                         #   N        : TRS file is updated after N traces
    ) as traces:
    # Extend the trace file with 100 traces with each 1000 samples
    traces.extend([
        Trace(
            SampleCoding.FLOAT,
            [random.uniform(-255, 255) for _ in range(0, 1000)],
            data = os.urandom(16)
        )
        for _ in range(0, 100)]
    )

    # Replace 5 traces (the slice [0:10:2]) with random length traces.
    # Because we are creating using the TracePadding.PAD mode, all traces
    # will be clipped or padded on the first trace length
    traces[0:10:2] = [
        Trace(
            SampleCoding.FLOAT,
            [random.uniform(0, 255) for _ in range(0, random.randrange(1000))],
            data = os.urandom(16),
            title = 'Clipped trace'
        )
        for _ in range(0, 5)
    ]

    # Adding one Trace
    traces.append(
        Trace(
            SampleCoding.FLOAT,
            [random.uniform(-255, 255) for _ in range(0, 1000)],
            data = os.urandom(16)
        )
    )

    # We cannot delete traces with the TrsEngine, other engines do support this feature
    #del traces[40:50]

    # We can only change headers with a value that has the same length as the previous value
    # with the TrsEngine, other engines can support dynamically adding, deleting or changing
    # headers.
    #traces.update_header(Header.LABEL_X, 'Time')
    #traces.update_header(Header.LABEL_Y, 'Voltage')
    #traces.update_header(Header.DESCRIPTION, 'Traces created for some purpose!')

    print('Total length of new trace set: {0:d}'.format(len(traces)))

Converting TraceSet from one type to another

import random, os, trsfile

with \
    trsfile.open(
        'trace-set',                  # Previously create trace set
        'r',                          # Read only mode
        engine='FileEngine'           # Using the FileEngine
    ) as traces, \
    trsfile.open(                     # Note: TrsEngine is the default
        'trace-set.trs',              # Name of the new trace set
        'w',                          # Write mode
        headers=traces.get_headers()  # Copy the headers
    ) as new_traces:
    new_traces.extend(traces)         # Extend the new trace set with the
                                      # traces from the old trace set

Documentation

The full documentation is available in the docs folder with a readable version on Read the Docs.

Testing

The library supports Python unittest module and the tests can be executed with the following command:

python -m unittest

Architecture overview

This diagram gives a quick overview on a conceptual level how different concepts are related.

Architecture overview

The API documentation

If you are looking for information on a specific function, class, or method, this part of the documentation is for you.