A Common Misconception
In the world of video technology, H.264 is one of the most widely used terms. Most people refer to it as a "codec," but this is technically incorrect. Understanding the distinction between a codec, a standard, and an encoder/decoder is important for anyone working with video.
What Is H.264?
H.264, also known as AVC (Advanced Video Coding), is a video compression standard — not a codec. It is a specification that defines how video data should be encoded and decoded. The standard is jointly developed by the ITU-T Video Coding Experts Group (VCEG) and the ISO/IEC Moving Picture Experts Group (MPEG).
What Is a Codec?
The word "codec" is a combination of "coder" and "decoder." A codec is a software or hardware implementation that encodes (compresses) and decodes (decompresses) video data according to a standard. Multiple codecs can implement the same standard.
For example, x264 and OpenH264 are both codecs (software implementations) that implement the H.264 standard. They follow the same specification but are different pieces of software with different performance characteristics.
The Correct Terminology
H.264 is a standard or specification. x264 is a codec that implements the H.264 standard. When you encode a video "in H.264," you are encoding it according to the H.264 standard using a codec like x264. The distinction matters because different codecs implementing the same standard can have very different performance, quality, and licensing characteristics.
Other Video Standards
The same distinction applies to other video standards: H.265 (HEVC) is a standard; x265 is a codec that implements it. VP9 is a standard developed by Google; libvpx is a codec implementing it. AV1 is an open royalty-free standard; libaom, SVT-AV1, and dav1d are codecs implementing it.
Why This Matters for Video Hosting
When choosing a video hosting platform, understanding these distinctions helps you make informed decisions about encoding quality, compatibility, and licensing. Kavimo uses industry-standard encoding pipelines to ensure your videos are compressed efficiently and play back correctly across all devices and browsers.