Traditional codecs use "macroblocks" (fixed 16x16 pixel areas) to process video frames. HEVC introduces , which allow the encoder to process larger and more flexible chunks:
For years, the HEVC (High Efficiency Video Coding) landscape has been dominated by two names: the reference encoder (HM) and the practical workhorse, x265. If you needed to compress 4K or HDR content, x265 was the default open-source answer. userhevc