Audio input to mp3 or wav file on USB Flash Drive?

I want to build a device which can take in an audio signal and store it as a wav or mp3 on a USB Flash Drive.

After searching i found some basic info.Please correct if i am wrong.

To be able to connect USB Flash Drive,I need a microcontroller with USB Host capability.

I found this for USB Host capability
http://www.circuitsathome.com/mcu/arduino-usb-host-part-3-descriptors

For audio processing I found
http://interface.khm.de/index.php/lab/experiments/arduino-realtime-audio-processing/

I am not sure on how begin.
Which microcontroller or development board should I use ?
Is it possible to do both mp3 or wav recording of an audio signal and storing on USB Flash Drive using a single microcontroller?If yes ,how do i go about doing it?

If storing on USB Flash Drive is complicated I don't mind using SD/MMC cards.

Please guide me.

Regards
BBalegere

The audio processing in that link is affecting the audio data. It is not converting the audio data to MP3 or wav format.

Do you know how to do that? Can you do it fast enough to keep up with the incoming audio data?

By the time you buy an Arduino, a USB Host shield, a microphone and audio amplifier, and batteries to power it all, it will be bigger and more expensive than buying a recorder.

If mp3 recording is not feasible,i don't mind wav recording.

Is wav file recording feasible?
If yes how do I do about doing it?

another case of arduino not being right for the job

I think MP3 encoding can be achieved on an ARM processor, using https://datatype.helixcommunity.org/

check out http://embdev.net/articles/ARM_MP3/AAC_Player which does decoding using the same software

You can use another ARM chip with USB host capability if you want to use USB mass storage disks instead, I think a LPC1768 may be a good starting point as opposed to the AT91SAM7, try a mbed

Don't know how close to your requirements this might be, but I couldn't resist it at that price, so I ordered one a week ago. Hasn't arrived yet so I can't give you a review.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=120663407599&ssPageName=STRK:MEWNX:IT

Lefty