FLV, also known as Flash video, is a popular format used to deliver video over the Internet using Flash Player. Right now, Flash Player supports H.264 video and HE-AAC audio, Flash video contents can be embedded within SWF files. FLV format has quickly established itself as the format of choice for embedded video on the web; and FLV formats are used widely on mainstream video website, for instance: YouTube, Google Video, Yahoo! Video.
Flash video can be played freely on web without installing additional codec requirements on most operation systems. The people can enjoy Flash video via widely available adobe Flash Player and web browser plugin, or one of several third-party programs, such as MPlayer, QuickTime, VLC media player.
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F4V is a video file format which is developed by Adobe Flash. F4V files belong to HD video. Since videos in F4V format are usually encoded in H.264, the F4V format is based on the format specified by ISO/IEC 14496-12: ISO base media file format. The Adobe Flash Player has been able to play F4V files with SWF files published for Flash Player 9 Update 3 (9,0,115,0). A large part of the F4V format involves metadata. When Flash Player loads an F4V file, various stream properties are made available to a running ActionScript program via the NetStream.onMetaData property. The available properties differ depending on the software used.
HD FLV is High-definition Flash Video, which generally refers to Flash video system of higher resolution than standard-definition (SD) video, most commonly at display resolutions of 1280×720 (720p) or 1920×1080 (1080i or 1080p). SD video is usually encoded by standard H.263 or MPEG video codec, etc; HD video is better video compression solution which adopts H.264 video codec. The HD FLV in H.264 delivers excellent video quality across the entire bandwidth spectrum — from 3G to HD and everything in between (from 40 Kbps to upwards of 10 Mbps).
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Related software: Video to FLV Converter
H.264 is a standard for video compression, and is equivalent to MPEG-4 Part 10, or MPEG-4 AVC. H.264 is the next-generation video compression technology in the MPEG-4 standard, also known as MPEG-4 Part 10. H.264 can match the best possible MPEG-2 quality at up to half the data rate.
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FLV and F4V are also known as Flash video, which are popular formats used to deliver video over the Internet using Flash Player. But FLV usually refers to SD video (Standard-definition video), which is compressed by H.263, MPEG video codec. F4V usually refers to HD video (High-definition video), which is compressed by H.264 video codec. F4V video has better video quality and wider usages than FLV since F4V belongs to HD video.
HD FLV refers to a category of videos which is compressed by H.264 video codec.
At present, HD FLV is most popular on the Internet. Because it delivers excellent video quality across the entire bandwidth spectrum — from 3G to HD and everything in between (from 40 Kbps to upwards of 10 Mbps). And Flash Player can play all the Flash video included FLV, F4V and HD FLV.
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YouTube is a video-sharing website on which users can upload, share, and view videos. The company is based in San Bruno, California, and uses Adobe Flash Video technology to display a wide variety of user-generated video content, including movie clips, TV clips, and music videos, as well as amateur content such as video blogging and short original videos. Most of the content on YouTube has been uploaded by individuals, although media corporations including CBS, BBC, VEVO and other organizations offer some of their material via the site, as part of the YouTube partnership program.
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YouTube accepts videos uploaded in most container formats, including .AVI, .MKV, .MOV, .MP4, DivX, .FLV, and .ogg and .ogv. These include video formats such as MPEG-4, MPEG, and .WMV. It also supports 3GP, allowing videos to be uploaded from legacy mobile phones. All the video formats on YouTube use progressive scanning. Viewing YouTube videos on a personal computer requires the Adobe Flash Player plug-in to be installed in the browser. The Adobe Flash Player plug-in is one of the most common pieces of software installed on personal computers and accounts for almost 75% of online video material.
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