As of 2010[update] public releases of Flash Player (collaboration between Adobe Systems and MainConcept) also support H.264 video and HE-AAC audio.

[4] The 2002 release of Flash Player 6 added support for video in the SWF file format.

The 2003 release of Flash Player 7 added direct support for the FLV file format.

Flash Player does not check the filename extension but instead examines the file to determine the format of the thing created.

[6] Since 2002, the initial format is Flash Video and the file suffix is .flv with a MIME derived Internet media type of video/x-flv.

[14][15] Flash Player 8 and newer revisions also support the playback of On2 TrueMotion VP6 video bit streams (FourCC VP6F or FLV4).

[7][11] On2 VP6 can provide a higher visual quality than Sorenson Spark, especially when using lower bit rates.

Both these formats are bitmap tile based, can be lossy by reducing color depths and are compressed using zlib.

However, audio in Flash Video FLV files recorded from the user's microphone use the proprietary Nellymoser Asao Codec.

The first four bytes denote the size of the previous packet/tag (including the header without the first field), and aid in seeking backward.

The FLV packet encryption is generally inherited from a MP4 file that is stored on an Adobe Flash Media Server.

Video encodings enumerated from 0 are: Video processing parameters enumerated from 1 are: MPEG-4 encodings such as H.264, MPEG-4 ASP and AAC add a one byte value with a NULL value indicating that the payload contains MPEG-4 configuration details.

It has support for a scripting language called ActionScript, which can be used to display Flash Video from an SWF file.

Flash Player 9 Update 3, released on 3 December 2007,[20] also includes support for the new Flash Video file format F4V and H.264 video standard (also known as MPEG-4 part 10, or AVC) which is even more computationally demanding, but offers significantly better quality/bitrate ratio.

[5] In an interview with BBC News, the main programmer of Flash Jonathan Gay said that the company had wanted to use H.264 when video support was originally added to Flash, but had been deterred by the patent licensing fees of around $5 million (£3.5 million) per year.

[21] Flash Player supports two distinct modes of video playback: Microsoft Windows, Mac OS X, Unix-based Mac OS devices can play flash videos in QuickTime with the help of additional software (such as the open source Perian component.)

Windows Mobile, Palm OS–based The iPhone and Android devices can play flash videos with the help of additional software (such as the Skyfire web browser application.)