One method not mentioned is simply to use something like Click2Flash (you can also get it as a Safari extension here) and set it's prefs to allow downloading of the .flv which will have the added convenience of downloading the video as an H.264 if the site hosting the video supports that. Extracting the audio from the H.264 is straightforward after that.
Once you do download a vanilla .flv though you very well may find that VisualHub can't convert it to anything (*cries a little*), so you need to try some other options like this one. If it's a .swf you can try this.
TIP ON DOWNLOADING THE VIDEO FILE:
An easy built-in way is to find it in the Activity Window (Command + Option + A) of Safari and Option-Double-Click it.
Macosxhints' hint + comments can be broken down into this list of methods.
01) Open it in VLC.
02) Hit Shift+Command+W to open the "Streaming/Export Wizard" window.
03) Hit the "Transcode/Save to file" Radio Button.
04) Hit "Next" (Return)
05) Hit the "Existing playlist item" Radio Button.
06) Select the file to extract the audio from, from the list.
07) Hit "Next" (Return)
08) Tick the "Transcode audio" tick box.
09) For the Codec Pulldown select FLAC (you can really choose whatever is best for you here depending on your needs, Uncompressed may be quite useful.)
10) Hit "Next" (Return)
11) Confirm "RAW" is selected.
12) Hit "Next" (Return)
13) Choose... where to save the file file to.
14) Open the saved audio file in whatever audio editing tool you enjoy. The hint suggests Audacity.
- Use iExtractMP3. FREE. (Didn't try because it's last update was 12-05-08)
- Use RichFLV. FREE. (Didn't try it because it requires Adobe Air)
- Use ffmpegX. FREE. (You very likely already have this installed. It's a bit out of date though)
- Use SWFTools. FREE. (Installing is a bit complex and using the app itself is a little tricky)
- Use Miro Video Converter. FREE. (I've mentioned this one before. Can occasionally be handy, check it out.)
- Use Browser Extentions. (There are too many to list here)
- Use FLV Crunch. FREE (If you haven't tried this app you should give it a whirl)
- Use MediaConverter.org. FREE (It's a website that does conversion for you. I haven't used it much)
Using QuickTimeX and QuickTime Player 7:
01) Open it in QTX. (ymmv)
02) Export it to something QT7 can open.
03) Open it in QT7 and Export... it as audio. (Export Sound to AIFF or whatever your choice is)
04) Optionally, use the semi-hidden Extract audio function: With movie open hit Command + J for the Properties Window, click on the "Sound Track" you want, tap the Extract button at the top left of the window and then Save As... or Export... the resultant window to whatever you fancy. Notice the dot in the center of the close window widget, that means it's not saved.
(Terminal Madness Alert!)
00) Install FFMPEG (likely you already have this installed if you read this blog)
01) Fire up the Terminal and enter:
ffmpeg -i yourFLVfile.flv -acodec copy namethissomething.mp3
You can drag the file to be transcoded into the Terminal to find it's path. Likewise, you can drag the folder you want it outputted (that's a word?) into the Termainal as well to set the path to it.
Type: ffmpeg -i
Hit space bar
Drag in file to be transcoded
Hit space bar
Type: -acodec copy
Hit space bar
Drag in location for output file.
You can really do this with most files, not only .flv's, btw.
01) Open the file in Handbrake (ymmv).
02) Export it as .mp4.
03) Extract it with QuickTime Player 7 (or even Garageband if you don't have QT7 installed or whatever app you like.) People tend to forget Garageband can do some neat stuff with audio.
Using TubeTV and Switch (free version):
I haven't tried this method not just because TubeTV is old (circa 2008) but mainly because other methods are simpler and have more options. I didn't like this line at TubeTV's site: "High quality video conversions using the H.264 codec are performed with QuickTime® and Perian." Why not just use Perian then to begin with?
TubeTV is here.
Free version of Switch is here.
Using MPEG Streamclip: (thanks to reader "andthatallthereistoit")
01) Open the .flv in MPEGStream Clip. (ymmv depending on the type of .flv)
02) File > Export Audio.