FFMPEG Help

[consultant]

Just started using FFMPEG and am in a hurry. Can someone throw me a bone?

All I need to do is convert solve .flv files .mp4 H264 files. I want the resulting MP4 to be very close to the quality of the source (so same resolution, frame rate, bitrate, etc.) I of course don't want to create a file larger than necessary to simply come very close to reproducing the same quality as the original.

What are the recommended parameters I should use or at least familiarize myself with?

[consultant]

Well I discovered the -sameq parameter. Quality is the same except resulting mp4 is twice the size as the .flv. I would think the size should be at lot closer?

[sneaker_ger]

What video and audio formats do your .flv files have? Many already are H.264 and AAC and can simply be remuxed:
ffmpeg -i source.flv -vcodec copy -acodec copy destination.mp4

Otherwise use the same settings that others use to achieve transparency, i.e. use x264 with a preset of your choice and a CRF of 18 to 23.