The Difference Between H264 & X264

By Mac Pogue

Web video sites like YouTube would not be possible without H.264.
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Today's media-saturated society requires more and more efficient ways of storing and displaying video. Codecs are methods of storing a video--essentially the language in which a video is stored. Codecs are continuously updated and made more efficient. Essentially newer codecs say the same thing as old ones but in fewer words. H.264 became an instrumental codec in the web video boom, providing content makers with a method to store tons of video online in dramatically less space than before.

Codec vs. Encoder

In shorthand, H.264 is the codec and X.264 is the encoder. Codecs are the language, and encoders are the translators of that language. X.264 was developed in the early 2000s as a free command-line encoder to translate video into H.264. The makers of X.264 gave the utility away for free in the hopes of proliferating the new H.264 codec.

Uses of X.264

X.264's software has been incorporated into many programs. Since the encoder works only from the command line, developers have taken it and put it into the graphical user interface (GUI) of their programs. Programs such as ffmpeg, Handbrake, VLC Media Player and MeGUI use the X.264 backend. X.264 is in a way a transparent software, as a user's interaction with it is mediated through another software's interface.

Uses of H.264

H.264 is used today to put large amounts of video into any setting with limited bandwidth. Websites such as YouTube, DailyMotion, Hulu and Netflix all have capitalized on the H.264 codec's ability to squeeze a large amount of video into a small space. European HDTV is broadcast using H.264, along with Blu-ray DVDs. Videos saved to iPods and iPhones are saved in H.264 to maximize space and efficiency.

Why H.264 & X.264

H.264 and X.264 work in tandem to put more video into people's hands on demand. As broadband Internet proliferates and wireless Internet develops, more bandwidth will be devoted to video transmission. Netflix, a company that uses H.264 compression to stream movies to any home in the world, takes up the majority of Internet bandwidth in America during peak hours. Technologies like X.264 turn video into H.264 video so that you can enjoy movies, television and other content anywhere there is Internet.