Need Help on: Resistor Scan Project

[AR-Droid]

Hi everyone,
I am creating an application that processes Pictures of Resistors taken with SmartPhone Camera and then provide us the resistor values directly. For this I need several groups of resistor pictures from different sources so that I can understand (or at least try to understand) the quality and clarity of different smartphone cameras, their different resolutions, the lighting and different resistors normally used by people and so on. Use only smartphone cameras to take pictures and dont do any colour corrections.

If you would like to help then go ahead. Take some Resistor pictures with your Smartphone Camera and upload them.
It will only take a minute or two.

Please follow the procedures below for taking photos:

1. Picture's Background: Pictures with white background only are needed. Just take an empty white paper and put some resistors on it.
   
2. Resistor type: Use common resistor types only (1/2 or 1/4 watt that everybody normally uses with breadboards). Use only 4 colour band (3 for values + 1 for tolerance - gold) resistors with a beige or any similar white-like background colour (This resistor background colour is the recommended one; any other colour is also OK if you dont have that colour). A sample picture of resistors with beige background is shown below.
3. Resistor arrangement: Well, particularly nothing! Just put resistors in some random positions may be with one overlapping the other but make sure that all colour bands of all resistors are visible and not hindered by metal part of other resistors. Feel free to use more number of resistors.
   
4. Camera Lighting & Options: Dont use zoom (Zoom out fully if you are zoomed in). Dont take pictures with flash(set flash mode to off in options). Instead use some adequate lighting that doesn't make the picture too dark or too bright.
5. Positioning Camera and taking pictures: Try to move your phone as near as possible to the resistors. If you move too near you can notice that your camera's cannot autofocus the picture. If that happens move your camera a little above. And now take 2 or 3 pictures with different resistors.

Uploading the pictures taken:

( Uploading the pictures in your reply itself is not possible as there are image size, width and height restrictions in electronicspoint website and your pictures will be really big)​

After taking the pictures, upload it in any image site(such as imgur, flicker) or online storage(dropbox etc.,) as you wish but make sure that it is publicly available.
For anonymous uploading & sharing, please use this site's upload feature publicdomainpictures.net which shares your images in public domain i.e., anybody can use it. (Of course, uploading to it first requires signing up but your information is not shared with anyone).

Then share the list of IMAGE URLs in your REPLY. Also add the Megapixels of your camera.

Thank you for your time.

 

[davenn]

hi there

others have been here doing/asking the same thing

sorry but I am not interested in signing up to some other image site

Dave

 

[Gryd3]

hi there

others have been here doing/asking the same thing

sorry but I am not interested in signing up to some other image site

Dave

I don't blame you.
But for the sake of helping AR-Droid I would like to recommend a feature in your app to provide real-time feedback of which resistor it is currently focusing on. Take a look at some QR code apps and make not of how they put a box around the code they are scanning. This feedback will allow the user to adjust the camera angle/lighting/etc. in real time to get a good enough picture for your app to function.
Control the user, make them give you a decent picture. If a brown looks like a black and your app picks the wrong value, there could be a bit of a sh*t storm. You can't rely on your users providing good enough pics without feedback.

 

[shrtrnd]

I'm wondering how much longer they'll be using color bands. With the improved marking systems any more, I'm seeing more and more values being printed on the resistors.
Most of those using the European printed marking system.

 

[AR-Droid]

hi there

others have been here doing/asking the same thing

sorry but I am not interested in signing up to some other image site

Dave

Thanks for explaining your concern dave but there is a solution for this.
Imgur.com is providing an anonymous upload feature which does not even require you to sign up with your mail.
Open imgur.com --> Click the Image Upload button on the top left. --> Upload an image and thats it.
You will be given a unique URL link which you can post here. Uploading like this wont even post your image in the public gallery also.
If you are too concerned, here is a little info from Terms of Service of Imgur
About images you upload (from imgur.com/tos)
You can upload images anonymously and share them online with only the people you choose to share them with. If you make them publicly available, they may be featured in the gallery. This means that if you upload an image to share with your friend, only your friend will be able to access it online.

 

[AR-Droid]

I don't blame you.
But for the sake of helping AR-Droid I would like to recommend a feature in your app to provide real-time feedback of which resistor it is currently focusing on. Take a look at some QR code apps and make not of how they put a box around the code they are scanning. This feedback will allow the user to adjust the camera angle/lighting/etc. in real time to get a good enough picture for your app to function.
Control the user, make them give you a decent picture. If a brown looks like a black and your app picks the wrong value, there could be a bit of a sh*t storm. You can't rely on your users providing good enough pics without feedback.

I am gonna go through the concepts you have told one by one. First I think you slightly misunderstood the concept as you quoted "which resistor it is currently focusing on". It focuses at every single resistor on the photo. Also I developed a feature of putting a rectangular box(real-time feedback). But sorry it will be viewed only when the app launches as I have not completed the entire thing. Although I am thinking of a server based 'beta' version which will arrive soon. I accept your fact that controlling the user to give us decent pics is a great idea especially with brown/black problem. I have algorithms to tackle lighting source variations (in position & brightness) but the results are good enough even without using them. For angle, the smartphone is parallel to the paper or resistor pile.
Expecting your reply soon.

 

[Gryd3]

AR-Droid. This is not a sales site. Although the process you are envisioning does not require a sign-up, pushing the pros of the service to Davenn makes it sound like a sales plot.
The terms of service for Electronics Point could classify this as Spam and lock the topic.