{"id":1725791,"date":"2015-09-10T14:04:25","date_gmt":"2015-09-10T14:04:25","guid":{"rendered":"http:\/\/www.sweetwater.com\/sweetcare\/?post_type=articles&p=1725791"},"modified":"2015-09-10T14:04:25","modified_gmt":"2015-09-10T14:04:25","slug":"understanding-video-file-components","status":"publish","type":"articles","link":"https:\/\/www.sweetwater.com\/sweetcare\/articles\/understanding-video-file-components\/","title":{"rendered":"Understanding Video File Components"},"content":{"rendered":"

When working with video files, there are many different components to be aware of, such as codecs, bitrates, frames, etc. Sometimes, keeping all of these things straight can be a bit confusing. Luckily, our friends at Serato have broken down these key terms in their Video Files 101<\/a> article. Below is an excerpt from that article explaining each component or concept:<\/p>\n

Containers<\/h4>\n

Containers are file formats which are designed to contain varying kinds of encoding, usually of just audio, or audio\u00a0and<\/em>\u00a0video. When a media player tries loading a container file, it first reads the\u00a0header information<\/em>\u00a0which includes a summary of details about the information contained inside that file, such as the codecs used, and the bitrate and length of the streams.<\/p>\n

Streams<\/h4>\n

Video files are generally multimedia. That is, they contain video information, and the associated audio – the soundtrack.<\/p>\n

These are described as the video stream and audio stream respectively, or occasionally as the video and audio\u00a0tracks<\/em>.<\/p>\n

Codecs<\/h4>\n

Codecs encode information for storage or transmission, and subsequently decode it for playback.<\/p>\n

Video files usually contain both video and audio streams, which can be created with various combinations of audio and video codecs and stored within a single container.<\/p>\n

To successfully play a particular video file, the media player software used must have access to the codecs necessary to decode the streams present in the file.<\/p>\n

Bitrate<\/h4>\n

Bitrate is the amount of\u00a0bits<\/em>\u00a0per second used to encode a stream. For instance a 2000 kb\/s video stream uses 2000\u00a0kilo<\/em>bits per second of video, which equates to about 150\u00a0MB<\/acronym>\u00a0of disk space to store a 10 minute video (in this case with no audio streams).<\/p>\n

Each stream in a file has it’s own distinct bitrate.<\/p>\n

Frames<\/h4>\n

A video is made up of frames. Viewed by themselves, frames are still (that is, not moving) images, but when updated rapidly each second, frames become a moving image to the human eye. How many times a second the frames are updated is called the\u00a0framerate<\/em>.<\/p>\n

Keyframes<\/h4>\n
\n

Keyframes are used in compressed video formats which tell the codec useful information about the frames coming after them. This allows the frames\u00a0in between<\/strong>\u00a0keyframes to be compressed into a much smaller amount of data than if they each were a full description of the whole image. Often the in-between frame information can just be a list of the differences between the new frame and the previous one.<\/p>\n

In files designed for maximum compression, the amount of keyframes can be kept to a minimum, and a keyframe might only be used when the entire scene changes between one frame and the next, thus requiring a keyframe to describe fully the frames to come. This can present difficulties when a user wants to jump to different part of the video; the player might have to spend a long time finding the last keyframe, then decoding all the frames from there to the desired spot in the video.<\/p>\n<\/div>\n","protected":false},"featured_media":0,"template":"","categories":[1],"tags":[90495,90500,90499,90497,90496,44951,90498,54919,90502,90501,83726,54405],"storecat":[],"itemids":[],"manufacturers":[33712],"acf":[],"yoast_head":"\n\n\n\n\n\n\n\n\n\n\n\n\t\n