  The total energy consumption of today's video coding systems is globally
significant and emphasizes the need for sustainable video coder applications.
To develop such sustainable video coders, the knowledge of the energy
consumption of state-of-the-art video coders is necessary. For that purpose, we
need a dedicated setup that measures the energy of the encoding and decoding
system. However, such measurements are costly and laborious. To this end, this
paper presents an energy estimator that uses a subset of bit stream features to
accurately estimate the energy consumption of the HEVC software encoding
process. The proposed model reaches a mean estimation error of 4.88% when
averaged over presets of the x265 encoder implementation. The results from this
work help to identify properties of encoding energy-saving bit streams and, in
turn, are useful for developing new energy-efficient video coding algorithms.
