Sharing a small tip … I recently needed a lightweight tool to extract the audio components from an FLV file and save it as an MP3 file. After some searching I found that you can use FFmpeg to easily extract the audio.
C:\> ffmpeg.exe -i <input.flv><output.mp3>
C:\> ffmpeg.exe -i “D:\my video.flv” “D:\my video.mp3”
NOTE: please make sure you don’t leave out the “-i” to specify the input file. If you do leave it out, you may end up overwriting your original FLV file with an empty file.
This is the hardest part. You have three choices: