I want to track my physical Movement through iphone within my office using my office map.The map will show all rooms of my office.for example,if i move from administraion block to another block, i have to move one icon from administraion block to another block on the map.in other words, the icon should move as i move within office.is it possible to do in iphone SDK?any help please?
Can't really see how this can be done, most offices have terrible GPS reception. Thus using GPS is out of the questions, als it will not be precise enough.
You could try using bluetooth although it very limited in iOS and you would have to place bluetooth dongles every wehe.
My guess it can't be done with the precision that you need.
Related
What should I do if the compass on two or more different devices give me different headings? I tried to calibrate the compass on devices but anyway sometimes they show me differents headings.
Since the iPhone compass "works just like a magnetic-needle compass":
The accuracy of digital compass headings can be affected by magnetic or other environmental interference, including interference caused by proximity to the magnets contained in the iPhone earbuds. The compass may need to be calibrated from time to time (Apple: iPhone and iPad: Calibrating Compass).
You have several options for fixing the compass:
Follow the directions! Move the device in a figure eight motion. However, this looks like it isn't working for you.
"[d]isregard the message to calibrate". Some areas have more magnetic interference than others, like in a car because of its dashboard. You can just leave it alone because "[t]he device will eventually recalibrate after several turns. Note that it may need to periodically recalibrate while you are driving, depending on the level of magnetic interference present."
Reboot (Not the "Slide to Power Off" reboot). Hold the power button and home button until the Apple logo appears.
I'm pretty sure those are your options. There may be more, so I'll do more research.
If you just want to see which compass is wrong, get a real compass and compare it to the headings on the two iPhones. Which ever one it matches up with, the other phone is wrong. If you don't have a real compass, you can follow this tutorial to make a homemade one (which is more fun)!
Hope this helps!
Well, if 2 iOS devices give you 2 different readings then at least one of them has uncalibrated hardware. So is this a hardware question? I don't think there is much to do in terms of the program, especially if you have no idea what the exact skew is.
while in graduate school for biomedical eng I developed a device we called a "vein finder". It was a simple device that was good enough for our eng school to patent.
I think it would be very very easy to use the iphone camera to develop an iphone app whereby MD's/ nurses/EMT's could use the app to easily identify peripherial veins that are not visible to the naked eye. This would be invaluable in starting IV's and giving bedside medications. The vein finder was esp helpful for patients in shock who had poor venous filling and therefore didn't have veins that "popped into view" with a tourniquet.
It would require using the iphone light at specific wavelengths... anybody have any idea if that is possible?
I don't think you have any control over the flash light that illuminates images. You can only turn it on and off. I also doubt you would be able to get the specific wavelengths you need.
My suggestion would be to look into building a peripheral light device which plugs in to the headphone jack for power and has the necessary functions for emitting light at different wavelengths. That way, you would be able to get the exact result you require.
You may also need to look into the camera itself, as it may not have the ability to capture the light at the wavelengths you may require. Hope that Helps!
Do you mean overlaying veins over the picture on the camera? It would be easy if the veins are always in the same place... What would your imagined procedure be for using this app?
EDIT: You can not manipulate the iPhone light for different frequencies; you can only turn it on and off. You would need to get a separate external light for that.
To work around the fact that you can't set the wavelength of the built in light, you should use an external light along with the iOS device.
Apologies for massive necro!
The LED light of the iPhone is not the problem - most white light sources contain IR or near-IR (in fact they are made up from the entire visible spectrum). Daylight works very well too.
The problem is the receiver. Most camera lenses, including smartphones, have an IR filter - thus cutting out the useful part of the spectrum. All we need is a digital camera with IR filter removed, that has a viewfinder (where you'll see the veins).
I need to create an iPhone simple view that, based on the location of the user in the world, points the person to a never-changing Long/Lat location.
Is it possible to know this from the iPhone API?
Any examples?
This is possible on the current (3GS) iPhone, but not on earlier versions (which did not have a compass). The APIs that you'll need to use are in the CoreLocation.framework.
Search the app store for "mecca" and you'll turn up many, many applications that do exactly what you're asking about. You'll also find several applications that let you drop a pin anywhere on the map and have the app point you to it.
I've recently written code that does almost exactly what you describe.
Here's what you ned to do:
Calculate a heading from your current location to your target location. You should use "great circle" calculations, so they show a correct heading even when the destination is over the horizon. I found code (in Javascript) at this link to show me how to do this:
http://www.movable-type.co.uk/scripts/latlong.html
You want the section titled "bearing"
That code uses javascript library routines like "math.sin(x)" You can pretty much just delete the "math." part, and the trig functions work as is.
That will give you your bearing in radians.
You then need to get your compass heading (if on a 3Gs phone), convert it to radians, and use the compass heading to correct for the orientation of the phone. If you're running on a 3G, you can skip the compass heading and show the bearing based on North being at the top of the phone, and let the user orient their phone towards North themselves.
Duncan C
I saw at least 6 apps in AppStore that take photos when detect motion (i.e. a kind of Spy stuff). Does anybody know what is a general way to do such thing using iPhone SDK?
I guess their apps take photos each X seconds and compare current image with previous to determine if there any difference (read "motion"). Any better ideas?
Thank you!
You could probably also use the microphone to detect noise. That's actually how many security system motion detectors work - but they listen in on ultrasonic sound waves. The success of this greatly depends on the iPhone's mic sensitivity and what sort of API access you have to the signal. If the mic's not sensitive enough, listening for regular human-hearing-range noise might be good enough for your needs (although this isn't "true" motion-detection).
As for images - look into using some sort of string-edit-distance algorithm, but for images. Something that takes a picture every X amount of time, and compares it to the previous image taken. If the images are too different (edit distance too big), then the alarm sounds. This will account for slow changes in daylight, and will probably work better than taking a single reference image at the beginning of the surveillance period and then comparing all other images to that.
If you combine these two methods (image and sound), it may get you what you need.
You could have the phone detect light changes meaning using the sensor at the top front of the phone. I just don't know how you would access that part of the phone
I think you've about got it figured out- the phone probably keeps images where the delta between image B and image A is over some predefined threshold.
You'd have to find an image library written in Objective-C in order to do the analysis.
I have this application. I wrote a library for Delphi 10 years ago but the analysis is the same.
The point is to make a matrix from whole the screen, e.g. 25x25, and then make an average color for each cell. After that, compare the R,G,B,H,S,V of average color from one picture to another and, if the difference is more than set, you have motion.
In my application I use fragment shader to show motion in real time. Any question, feel free to ask ;)
I am trying to write a game. That game uses tilt effect, but i don't know how to test it on Iphone Simulator 3.0.
I search it on internet, but the result is zero. How can i...?
Short answer: You can't, not directly. You have to use a real device.
Longer answer: You could subclass UIAccelerometer and do as you like. You could simulate input, or write a client and server pair that sends acceleration information from a real device to your app running in the simulator, or from your Macbook's accelerometer if you fancy waving your laptop around.
Try https://code.google.com/p/accelerometer-simulator/. It does the same thing as iSimulate -- it sends accelerometer events from the phone to your computer -- but it's free and open source.
There's an application in the AppStore called iSimulate which lets you feed an actual device's accelerometer inputs into the sim. You do need to have a device for testing.
ON a related note, you can also capture accelerometer data from safari running on your iphone/ipad
See this demo http://www.webdigi.co.uk/blog/2012/using-an-ios-device-to-control-a-game-on-your-browser/
Just saw this when asking a similar question - you can actually set the interface orientation now in the new xcode, so even though you can't 'tilt' it directly, you can make it to where it only supports landscape - then it will load the landscape view in the emulator! :D
From: http://developer.apple.com/library/ios/#documentation/IDEs/Conceptual/iOS_Simulator_Guide/InteractingwiththeiOSSimulator/InteractingwiththeiOSSimulator.html
Place the pointer where you want the rotation to occur.
Hold down the Option key.
Move the circles that represent finger touches to the start position.
Move the center of the pinch target by holding down the Shift key, moving the circles to the desired center position, and releasing the Shift key.
Hold down the mouse button, rotate the circles to the end position, and release the Option key.