Filtering using C++

The sample metavision_filtering.cpp shows how to use Metavision SDK pipeline utility to filter and display events. It also shows how to capture the keys pressed in a display window and use them to modify the behavior of the stages while the pipeline is running.

The following filters can be applied via keyboard keys:

r - Metavision::RoiFilterAlgorithm
p - Metavision::PolarityFilterAlgorithm used to show only events of positive polarity
n - Metavision::PolarityFilterAlgorithm used to show only events of negative polarity

The source code of this sample can be found in <install-prefix>/share/metavision/sdk/core/cpp_samples/metavision_filtering when installing Metavision SDK from installer or packages. For other deployment methods, check the page Path of Samples.

Expected Output

The sample visualizes CD events from an event-based device or a recording (RAW or HDF5 event file) after filtering:

How to start

First, compile the sample as described in this tutorial.

To start the sample based on the live stream from your camera, run:

Linux

./metavision_filtering

Windows

metavision_filtering.exe

To start the sample based on recorded data, provide the full path to an event file (here, we use the file spinner.hdf5 from our Sample Recordings):

Linux

./metavision_filtering -i spinner.hdf5

Windows

metavision_filtering.exe -i spinner.hdf5

Code Notes

The code of this sample is explained in the page Example of Building a Simple Pipeline within the chapter on pipelines.