Energy Consumption and Carbon Footprint of Modern Video Decoding Software

The estimation of energy consumption has become vital in developing eco-friendly and sustainable video streaming solutions to monitor CO2 emissions. In this paper, we seek to evaluate and compare the energy consumption and CO2 emissions of the decoding process related to three popular video coding standards, namely AVC, HEVC, VVC, along with two video formats VP9, and AV1 through their real-time software decoders, including h264, hevc, VVdeC/OpenVVC, vp9, and libdav1d. The evaluation is conducted on two types of consumer hardware, desktop PC and laptop. To ensure a fair evaluation, we also assess the coding efficiency of software encoder implementations using three objective quality metrics. The experimental results revealed that the h264 decoder consumes the lowest energy and is associated with the lowest CO2 emissions compared to other decoders on both hardware platforms. On the other hand, the VVenC encoder enhances coding efficiency at the cost of increased decoding energy consumption and CO2 emissions, particularly noticeable in the case of the OpenVVC decoder. Meanwhile, x265/hevc achieves a compelling balance between coding efficiency and decoding energy consumption. The full results of this work are available at https://decodingenergy.github. io/decoding_energy_co2.html.