H.265, or High Efficiency Video Coding, is a new video coding standard that specifies how to decode video. It’s basically the video equivalent of a .JPEG file. The codec helps your computer understand how a stream of data can be displayed as a video file rather than gobs of randomly distributed colors.
Interestingly, a video coding standard doesn’t define how video is encoded into a file. Tom Vaughan, the Vice President of product management and marketing at MultiCoreWare, developer of the open-source x265 encoder, clarified this. “When you define a codec, the only thing really defined by the spec is the syntax of the compressed video stream, and the method to decode it. Video encoding isn’t defined by the standard.” This is why there are many different video encoders, and some are more efficient than others.
So, what’s the difference between H.265 and HEVC? There isn’t one. Each is a different name for the same codec. The standard was defined by the Moving Picture Experts Group (MPEG) and the Video Coding Experts Group (VCEG), and each calls it by a different name, but the standard is the same.
And what about x265? That’s the open-source encoding project, not the standard. It’s the most popular way to encode video to HEVC, but it’s not the only choice.
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