pyplis 0.9.2

A Python library for the analysis UV SO2 camera data

pyplis is a Python toolbox for the analysis of UV SO2 camera data. It includes a large collection of routines for the analysis of such data, for instance:

1. Several routines for plume background estimation

2. Automatic cell calibration

3. DOAS calibration routine including two methods to identify the field of view of a DOAS instrument within the camera images

4. Plume velocity retrieval either using an optical flow analysis or using signal cross correlation

5. Detailed analysis of the measurement geometry including automized retrieval of distances to the emission plume and/or to topographic features in the camera images (on a pixel basis)

6. Routine for image based light dilution correction

Note

The software was renamed from piscope to pyplis on 17.02.2017

Requirements

Requirements are listed in the order of likelyhood to run into problems when using pip for installing them (on Windows machines you may use the pre-compiled binary wheels on Christoph Gohlke’s webpage)

• numpy >= 1.11.0

• scipy >= 0.17.0

• opencv (cv2) >= 2.4.11

• Pillow (PIL fork) >= 3.3.0 (installs scipy.misc.pilutil)

• astropy >= 1.0.3

• geonum >= 1.0.0

  • latlon >= 1.0.2

  • srtm.py >= 0.3.2

  • pyproj >= 1.9.5.1

• pandas >= 0.16.2

• matplotlib >= 1.4.3

Optional dependencies (to use extra features)

• pydoas >= 1.0.0

• scikit-image (skimage) >= 0.11.3 (for blob detection in optical flow analysis)

We recommend using Anaconda as package manager since it includes most of the required dependencies and is updated on a regular basis. Moreover, it is probably the most comfortable way to postinstall and upgrade dependencies such as OpenCV (see here) or the scipy stack.

Installation

pyplis can be installed from PyPi using:

pip install pyplis

or from source by downloading and extracting the latest release. After navigating to the source folder (where the setup.py file is located), call:

python setup.py install

On Linux:

sudo python setup.py install

In case the installation fails make sure that all dependencies (see above) are installed correctly. pyplis is currently only supported for Python v2.7.

Code documentation

The code documentation of pyplis is hosted on Read the Docs

Getting started

After installation try running and understanding the example scripts. The scripts require the example data (see also following section for details).

Example and test data

The pyplis example data (required to run example scripts) is not part of the installation. It can be downloaded here or automatically within a Python console (after installation) using:

import pyplis
pyplis.inout.download_test_data(*local_path*)

which downloads the data to the installation data directory if local_path is unspecified. Else, (and if local_path is a valid location) it will be downloaded into the specific directory which will then be added to the supplementary file ./data/_paths.txt such that it can be found by the test data search method:

pyplis.inout.find_test_data()

The latter searches all paths provided in the file ./data/_paths.txt whenever access to the test data is required. It raises an Exception, if the data cannot be found.

Note

If you download the data manually (e.g. using the link provided above), please unzip it to a suitable location my_testdata_is_here and let pyplis know about it using:

import pyplis
pyplis.inout.set_test_data_path(*my_testdata_is_here*)

The path is then added to ./data/_paths.txt such that it can be found by:

pyplis.inout.find_test_data()