9781422277393

Tech 2.0

Codecs and Containers A digital video file is made up of two parts: the codec and the container. The codec is used to compress the file, mean- ing that it takes a large amount of data and makes it smaller. This allows the file to be more easily transferred, stored, and streamed. The codec also decompresses, or expands, the file. This restores the file to its initial size. The container is a collection of information about the digital video file itself, in- cluding its images, sound, and any other components. To put it another way, containers “contain” all the parts of a video, while codecs encode and decode its data. Codec names are highly technical, but you might recognize some popular con- tainer file names including AVI, WMV, and MOV. another option. Videos couldn’t be shared as easily. “They were too big to email back and forth,” Chen later explained, but that wasn’t the only difficulty. “You had to download different things based on what digital cameras people had.” These extra steps were a hassle. There were many different video formats, and each one used a different language, or codec . Without that codec, a movie was unwatchable. Sharing videos over the internet seemed to be more trouble than it was worth for the average user, so most people just gave up and didn’t even try. “We really started to see that this was an unmet need, not just recently, but from all the way stretching back to the first videos that were taken,” Chen said. “They were just living on computers and they

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