  We study 100 images of early LHC collisions that were recorded by the ATLAS
experiment and made public for outreach purposes, and extract the charged
particle multiplicity as a function of momentum for proton-proton collisions at
sqrt(s) = 7 TeV. As the collisions we study have already been pre-processed by
the ATLAS Collaboration, the tracks are visible, but are available to the
public only in the form of low-resolution bitmaps. We employ two separate image
processing methods, one based on the industry-standard OpenCV library and C++,
another based on self-developed algorithms in Python. We present the transverse
momentum and azimuthal angle distributions of the particles obtained through
both methods, in agreement with the literature.
