Hmmm, the shut down function could 'or' up multiple algorithms. The motion detection on a wide view could reveal how fast a hand is approaching, if too fast to always avoid a descending tool, shut down. A stationary hand holding the material would be much more common though. Many materials, textiles for example, are punched with a foot operated switch without clamping and both hands are often in danger. Even the operators, who's limbs are in danger, despise safety devices that interfere with their work. I can't count the times that I've seen disabled safety devices. That's what I like about an out of the way camera or a light level detector being the decision maker.

I have a potential application where I want an iPads camera to view an industrial process. Real time images then get processed and a yes/no decision is made. I would then need to output that decision via the lighting cable to a circuit that closes a real world relay to divert a part on a conveyor belt.

Does Pythonista allow real time access to the IPad camera. Can I control the frame rate of the camera?
Does Pythonista allow real time input/output across the lighting cable?

Here's my Dropbox link to some still photos of a hand under laser cross hairs.
https://www.dropbox.com/sh/gi6rej7mqa7edz4/AAD5WcHp8hXVt132peINxIUHa?dl=0
If anybody's interested I would email you copies.

Maybe the computer language or speed of processing is initially not as important as the logic of analyzing individual frames.

I've decided that I'll probably never make a bunch of money with my idea and in keeping with the concept of open source and with the existence of guys like you all; here it is.

It's an industrial worker safety issue. There always seems to be a trade off between worker safety and worker productivity. I've noticed one instance where drastic improvements can be made without that trade off.

You are all probably familiar with the relative new laser line cross hairs that can be added to drill presses for under $20.00. Also appropriate for punch presses and such. The machines they are added to mostly manipulate flat material stock. The laser lines are of a very distinctive color for the given laser. The lines are very straight lines... Until a human hand enters the field of vission. Then the laser lines trace out the top curvature of the hands and/or fingers. So if imagine processing detects anything but 'straight laser lines' machine operation could be prevented. The speed at which a hand enters the field of vision and the time it takes to stop the descent of hand mangling tooling would be crucial. World wide this could save many hands and fingers! It could also increase productivity! While there would be many problems along the way to a commercial version, such as UL lab approval and/or other safety standards one has to start someplace. I'm thinking the proper starting place is with old dogs and new toys.

Wow!
It's good to know I'm not the only old dog out here tinkering with the stuff of young'ings. I've noticed that young guys often miss really cheap and simple upgrades to old machinery. Like wire wrapping up a hard wired TTL Logic replacement for complex relay logic. It shrinks down the physical size of relay logic so that many new functions can be added without increasing the size of the old electrical box. Interfacing denounced input switches and real world output power is the only tricky part and the old relays can be repurposed to do that for many newly added functions. The parts cost for such an upgrade can be very low! I've upgraded several WWII machines so that they compete nicely with newer super expensive industrial ladder logic machines.

By the time I can actually complete my project in full the IPad Air 2 might just be the obsolete cheapo device I'm looking for.

I like the sound of mteep's coment:

"The iPad hardware, particularly the Air 2, could most likely do whatever computer vision processing you need blazingly fast on the GPU if properly coded. But this would be a lot easier to develop in Swift or Objective-C in Xcode."

So... The learning curve of another language? I started coding in machine language on an IBM machine in 1965. You had to input the boot program with binary paddle switches every time you started it up. If I remember correctly it was an IBM 1620. Then in Fortran followed by C. There were hundreds of people like me with physics, math and engineering books at the left elbow and boxes and boxes of IBM punch cards under foot. Industry needed subroutines for everything! When the 8080 8bit processor came out I built my first computer from a Digital Group kit. it was back to machine language. Then basic, then C and C++ as the 8080 evolved to drive a real desktop. That fun ended as the pins on processors got so numerous and so tiny you needed multilayer boards, flow soldering and expensive stuff to check timing diagrams. I've been into and out of coding since those years. But current devices now offer so much power in such a small package I just can't resist tinkering with them. Pythonista seemed perfect! I repair and modify exotic machines for small manufactures now and I've used Pythonista to analyze and model processes and machines that were not doing what was wanted. Pythonista has served me well so far, mainly just scientific and statistical stuff, no web programming.

Now programming languages have evolved to a level that has passed me by. I would like to work in a language that is most similar to C++ and one that can be compiled into machine code for speed. Ive often found it easier to write my own foundations rather than decipher packaged software. But the foundations are now so extensive that approach is flawed.

Finally, I have a real question:
Which programming language has the clearest documentation with extensive examples? Swift? Xcode? Or another. What machines can they be run on. And a wild guess as to the cost of obtaining and maintaining the development suite.

So, I thought I posted this earlier today, but it's not there now. Don't know if I didn't complete the posting or if it was removed because of some rules I'm unaware of. Anyway, here goes again.

Using the new method of the Image module I can creat what I want. I can combine images using the paste method. I can display the combined images in the council with the show() method.

But I want to display the images using the draw method of ui.View.

Is there a simple way to do this without first saving the images to disc?

mteep,
There are industrial tools that use BLE to wirelessly connect to sensors.
Although not an imaging application this link is particularly interesting in that it makes full use of a lot of other cell phone features.
http://defelsko.com/smartlink/smartlink.htm

Thanks dgelessus,

I was afraid of that but thought it worth asking. It seems like the lightning cable is connected to a fairly standard 'serial port' that can be written to, somehow. My application has strict cost, space and weight requirements. I'm eventually hoping to use outdated cell phones. Guess I'll have to search for a young NASA kid into robotics. I'm also looking into the Rasberry but it has no display screen, requires a box and requires a separate unit as the web cam. Cell phones would be the perfect machine, if only they can be modified to do the job. They could even call somebody if they detected a malfunction.

I don't 'spose there's any body from Apples hardware section on this board?

Thanks JonB.
This works.
There is some strange scaling going on if my ui.View has a width and/or height different from that of the pil Image. I don't understand that part of it yet but you've moved me well along my way. Thanks!