[any ANONYMOUS forum user]

FLV
Video: Sorenson Spark, Screen video, On2 VP6, Screen video 2, H.264
Audio: MP3, ADPCM, Nellymoser, Speex, AAC

SWF
Video: Sorenson Spark, Screen video, On2 VP6, Screen video 2, H.264
Audio: MP3, ADPCM, Nellymoser, Speex, AAC

F4V (MP4)
Video: H.264
Audio: MP3, AAC, HE-AAC

Please note that usage of H.264 (MPEG-4 AVC) video codec and AAC audio codec the FLV container has some limitations, so F4V (MP4) should be used instead.

Please note that besides H.264 video, AAC/MP3/HE-AAC audio, .FLV files support GIF, PNG, JPEG images (still frame data).