lots of encoders at vcdhelp.com. free? yes some, but cant suggest any for encoding .flv as i have never worked with that type of video- plenty of guides/ how to's , forum etc also at vcdhelp. some may do a better job than others or be easier to use. i would try several before deciding on one.
safe: pretty sure all the tools are ok (malware free). never had any issue with anything from vcdhelp.com and i have used many encoders. if you want let me know what your getting and i will check it out for you.
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