I'm new to html5 programming and was thinking of building an html5 app for iphone. I was wondering if there was any information in the API about sensing temperature on touch in the api? My app depends on the temperature of ones finger when they touch the screen. Is there anyway to measure this? IF not, is there a way to measure the amount of pressure applied to the screen?
Thanks!
Room temperature: Yes.
The temperature of your thumb on the iPhone screen: no.
The pressure of your thumb on the screen: also no.
Remember - the iPhone "touch" works on capacitance, not "mechanical pressure".
Related
Hello and welcome to my first question on stackoverflow.
I have found an app in the AppStore called „heart rate free“ the app tracks the pulse rate with the camera on the phone. To measure to pulse you have to put your finger onto the camera when the flashlight is turned on. I compared the readings with my Apple Watch and it’s seems legit (I wore my watch after the measurements)
My question:
How is the app programmed to measure the pulse when the camera sees only a red point?
And is it possible to build this with a webcam and python?
screenshot of the app
I couldn't find an answer to this question, and looking at Apples own apps like iMovie on iOS, the video picker does not offer a slow motion option on the iPhone 5S.
The image picker offers very little control over the video. If you are willing to dive deeper into the APIs you can use AVFoundation to capture your video and manipulate the camera properties as you see fit.
iOS 7 introduces a new AVCaptureDeviceFormat class that will give you the maximum and minimum supported frame-rates for the capture device, and you can use these to set a custom frame rate on the camera itself. I don't have an iPhone 5S to hand so I can't actually verify whether this API goes all the way down to 120FPS.
I want to implement a Metal Detector app which will react to a magnetic field in the phones surroundings.
How do I read the magnetic field readings from the magnetometer on the iPhone? Does anyone have sample code for accessing the magnetometer readings directly?
Thanks!
I would recommend you look at the O'Reilly book called iOS Sensor that is coming out. They have an entire chapter (6) on the magnetometer and a sample app.
iOS Sensor Programming
Apple Sample Code for Reading the Raw Values from the Magnetometer
No. You can't.
UPDATE : there is no metal detecting components in iPhone. However, there is a magnetometer available since iPhone 3GS. The Compass App makes use of the sensor to detect direction. It just reads magnetic North, but not reading magnetic fields surrounding. Therefore, you can't make a metal detector with it.
Physics Fact: Metal does not generate magnetic fields. Magnets do.
p.s. correct me if I am wrong.
There is already an app which does this. Check this and this blog.
This is what the description says,
The app has an adjustable sensitivity and makes an audible sound
signal if the sensitivity reaches a medium level. The phone needs to
be shook once to be calibrated if you intend to use the device again.
The app makes use of the magnetometer on the iPhone to find
interference with the compass to detect metal objects. Just hover the
backside of your mobile, the area under the camera, over the metal and
the app should find the metal and there should be an increase in
sensitivity.
However I am not sure if it is a fake app or it can be really done this way. Try downloading that and check it yourself. It is a free app.
In an iPhone App, I have to implement a feature such that user can make video through iPhone app and digitally zoom it also. Digital zoom feature should work while making videos. Any ideas how can I implement this?
Check out wikipedia. Bilinear is common because its fast (but the results are low quality).
I know this has been asked before, but the answers that I see are 2 years back. So I'll rephrase the question: are there any new power management APIs in iOS4 that I can take advantage of to turn off the screen?
-Overlaying a black view on top of an existing view still drives the screen's backlight and refresh rate.
Can I let the device screen timeout normally and then run my app in the background? I need to collect accelerometer data.
Thank you!
As far as I know you can't collect accelerometer data while the phone is locked. Also there are no power management APIs.
I found this for you tho where they give a trick of using proximity sensor but that doesn't seem like a reasonable solution. Enable iPhone accelerometer while screen is locked