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Digital video coding aims to reduce the bitrate and keep the integrity of visual presentation. High-Efficiency Video Coding (HEVC) can effectively compress video content to be suitable for delivery over various networks and platforms. Finding the optimal coding configuration is challenging as the compression performance highly depends on the complexity of the encoded video sequence. This paper evaluates the effects of motion content on coding performance and suggests an adaptive encoding scheme based on the motion content of encoded video. To evaluate the effects of motion content on the compression performance of HEVC, we tested three coding configurations with different Group of Pictures (GOP) structures and intra refresh mechanisms. Namely, open GOP <i>IPPP</i>, open GOP <i>Periodic-I</i>, and closed GOP <i>periodic-IDR</i> coding structures were tested using several test sequences with a range of resolutions and motion activity. All sequences were first tested to check their motion activity. The rate–distortion curves were produced for all the test sequences and coding configurations. Our results show that the performance of <i>IPPP</i> coding configuration is significantly better (up to 4 dB) than <i>periodic-I</i> and <i>periodic-IDR</i> configurations for sequences with low motion activity. For test sequences with intermediate motion activity, <i>IPPP</i> configuration can still achieve a reasonable quality improvement over <i>periodic-I</i> and <i>periodic-IDR</i> configurations. However, for test sequences with high motion activity, <i>IPPP</i> configuration has a very small performance advantage over <i>periodic-I</i> and <i>periodic-IDR</i> configurations. Our results indicate the importance of selecting the appropriate coding structure according to the motion activity of the video being encoded.