#How to use wolfram mathematica 10 update#
#How to use wolfram mathematica 10 software#

The one pointing towards the Pentagon on 911 couldn’t even capture the plane or rocket (whatever theory you believe in) using even more frames per second.

#How to use wolfram mathematica 10 software#

Most professional motion-detection software uses at least 5 frames per second. Plenty of time to get in, steal or break something, and disappear (or momentarily hide beneath the desk or somewhere else off camera). However, if this is supposed to be used as a practical application, I’d caution a few things: a) 15 seconds is a lot of time. (OK, not really!) Not bad for a couple dozen lines of code! Later that night I get the following emails. This gives me 60 seconds to leave the room and then runs the task every 15 seconds, keeping a 4 minute buffer of background images. I might want to run overnight computations at the same time, or have other events happen periodically, so instead I program a scheduled interrupt (another new capability) that will suspend any running Mathematica program, run this command, and then return to the program. I could use an infinite loop, but that would lock my Mathematica completely.

#How to use wolfram mathematica 10 update#

We want to update the store regularly, so that lasting changes such as an item being taken from the scene or placed there, or the sun setting, do not produce repeated alerts.įinally, we need to call the function repeatedly. Next I want to check the current scene against a time lagged store of what the image should look like. I ignore the case of over 70,000 pixels, as I don’t want an alarm when someone turns off the office lights and the entire image changes. If the size of the biggest change is more than 1,000 pixels, then we will call that an intruder event, and we will use the SendMail command to send me email to tell me about it together with the highlighted changed image. Now I can create a function that tests and acts on the result of the scene changes. Had the coffee cup been removed or another added, we would see a second smaller component listed as well. In this case there has been one scene change of over 37,000 pixels. Secondly, we can use it as a measure of the amount that has changed.

I will use it to darken the rest of the image by 75% and add a white line around the edge of the changed area. We can use this simplified scene-change image in two important ways.įirstly, we can use it to highlight what has changed in an image. So let’s put those steps together into a function. This is all we need to detect an intruder. Now we clump together these differences by filling in gaps of 10 pixels or less. I have applied this to the maximum difference out of all the color channels, since we want a change in color to be as important as an overall change in brightness. I don’t care how different they are, so I will apply a threshold. This image is black where there was no difference between the images. As a quick way to deal with that, I first blur both images slightly. My camera isn’t very good, so there is a bit of noise. ImageDifference gives us a pixel-by-pixel absolute difference between the two images. Let’s get some test images using the webcam on my laptop.Īnd again, but with a couple of seconds to hide from the camera:

Time to build some office security using Mathematica Home Edition!įirst, I am going to make use of an imminent new Mathematica command CurrentImage, which will import a real-time image from a video device. Ever since I wrote the “ Doing Spy Stuff with Mathematica” blog post, I have had a feeling that I am being watched.