  Energy and compression efficiency are two essential parts of modern video
decoder implementations that have to be considered. This work comprehensively
studies the following six video coding formats regarding compression and
decoding energy efficiency: AVC, VP9, HEVC, AV1, VVC, and AVM. We first
evaluate the energy demand of reference and optimized software decoder
implementations. Furthermore, we consider the influence of the usage of SIMD
instructions on those decoder implementations. We find that AV1 is a sweet spot
for optimized software decoder implementations with an additional energy demand
of 16.55% and bitrate savings of -43.95% compared to VP9. We furthermore
evaluate the hardware decoding energy demand of four video coding formats.
Thereby, we show that AV1 has energy demand increases by 117.50% compared to
VP9. For HEVC, we found a sweet spot in terms of energy demand with an increase
of 6.06% with respect to VP9. Relative to their optimized software
counterparts, hardware video decoders reduce the energy consumption to less
than 9% compared to software decoders.
