Features:
Convert video files into Macromedia Flash SWF and FLV
Flash Video Studio can convert the most common every video file formats:

Microsoft Windows Video Files (AVI, WMV, ASF)
MPEG Video Files (MPEG, MPG, MPV)
Quicktime Video Files (QT, MOV)
MPEG4 (through AVI format)
DIVX (through AVI format

Support All Flash Video Format
Several Flash Video Compression formats are supported to encode your video files:

New AVC/H264/MPEG video format. 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. To cut the story short, H.264 provides DVD quality at about half the data rate of normal DVD. See high definition video encoded using H264.
Flash 8 Video (On2 True Motion codec). Dual pass encoding is supported.
Flash 8 + Alpha video.
Sorenson (Flash MX)
Zip / Screen

H264 video encoding format gives you the best quality and very small file size.