I’m linking this back to a post I made a few months ago:  Jarvis from Iron Man It was a popular post apparently.  So far it has 38 comments from people wanting a similar system.  Unfortunately I haven’t been able to do anything with it, but the people in the comments section seem to have a pretty good grasp on things.  “PhysicistJedi” posted a link to a deviant art screencap,  Which reminded me of some applescripts that could be used to get the data using xml and rss feeds (I think… will have to dig up those links).  One of the things I was mostly interested in the whole Jarvis thing was the speech recognition.  Now, I’ve made applescripts to run speech recognition things before.  On macs there’s speech recognition built in, and after making a script for some of my favorite itunes playlists, I can say outloud “Computer play five star” and my computer will start playing my five star music.  This is problematic though because now that the computer has started playing the music it can’t hear me.  Herein lies the speech recognition problem.  For one of my many side projects (I have quite a few unfortunately) I want to try and fix that.

It may be a hardware limitation, but (theoretically at least) it should be possible to subtract the computer’s own audio from the input.  Going back to basics… sound is transmitted through the air in waves.  And just like in water they are susceptible to constructive and destructive interference.  So if you have two waves with a certain frequency, say 5 Hz, each travelling in opposite directions, and both of the same intensity… depending on how they are lined up (or in phase) with each other you get interference.  If the peaks for both of the waves overlap you get constructive interference, which causes the amplitude of the waves to double.  BUT if they are perfectly out-of-line (the peaks of one wave line up with the troughs of the other) you get DESTRUCTIVE interference, and in this particular case the waves cancel out completely.  If you were standing between the two (and could physically hear 5 Hz), if they were out-of-phase you wouldn’t hear anything.

Now, how does this apply to speech recognition?  The computer knows what it is outputting to the speakers, and most computers (mine at least) have a microphone.  If you could simultaneously take the output audio and subtract the input (mic) audio, given some calibration and applying the correct offset… anything that the mic picks up that the computer is not outputting should be heard clearly by the computer.  So… if (in the application I write) I tell my computer to play the five star playlist (it starts), but then I decide I want the volume turned down, or it to stop… I should be able to say just that, and it should happen.

In sound-cards I think this is referred to as full-duplex.  That’s when a sound card can record and output audio simultaneously.  So mine should be capable.

To-do:

• Access the output audio (by frequency, unless there’s an easier way I don’t know about…yet… as an example display the waveform or frequency distribution)
• Access the input audio (mic, same as above)
• Make an audio input filter that takes these two and subtracts the difference
• Apply different calibrations to make this work correctly (phase offset, amplification, etc)
• Figure out that pesky speech recognition thing (hopefully plug into the pre-existing system).

Some of the other projects (related to this) that I’d eventually like to work on:

• Home automation stuff using my macs
• Multi-touch display (http://nuigroup.com/)
• Artificial Intelligence to tie the above projects together
• Making my own version of this:  NanoBrewMaster Home Brew Station (should allow me to track what ingredients, timings, temperatures, etc I use… tie this into the home automation stuff)

And a neat idea I thought up and might toy around with is doing something with LEDs… the idea being you could hang it on a wall in your bedroom somewhere… it’s computer controlled, and it would simulate a sunrise (might make getting up in the morning easier).  If I don’t… I could just put a light on a timer… haha.  The sunrise effect would be cool though.

I just said I’m going to be saving up for a house… and here I go spending $200 (hopefully less) in a weekend going to Whistler.  FAIL

This is one of those things that I’m actually split on.  Part of me wants to go (really wants to go)… and part of me wants to stay (really wants to stay).  I just paid off last months credit card bill so I have no cash on hand (I bought my Macbook Air last month, not sure where the rest of the money went though… rent here in Bremerton probably…).  Part of the reason why I’m in Seattle and not San Diego is to go snowboarding… and with 7 weeks down having not gone it’s about time.  After this I’m done.  Not spending any more money.  I’m eating ramen from now on.  Seriously.

Website update:  I added some more menu options, now there’s a link to my Flickr account and a link to TV reviews (figure I’d add those in with the rest of them).  I’ll probably post per-episode reviews for some shows.  I also made a post for everything I own, media-wise.  So you’ll see on the Movie/Games/TV pages that there’s the box art for the stuff I own up there, along with a list of everything I own.  Took me a couple hours to put everything up there, cause I had to do it by hand.  I also integrated my Xbox gamertag into the theme of the Games page.  It syncs with the microsoft server that hosts it.  Pretty cool I think.  Oh, and the music page displays the album art from my last.fm account.

Per usual, I’m on the ferry heading to Seattle at the moment, where Ron and some other people will be picking me up to goto Whistler.  I’m also bringing my camera and tripod so hopefully I can take some sweet pictures.  Hopefully we’re staying somewhere nice with a view (and cheap, cough)