Camera focus/exposure/zoom advice.

[Nathan Kellert]

I need some advice on how to configure the camera. What my client needs me to do is create an application geared towards scanning for tiny barcods. Were talking like 1/8."  Sean already answered a question similar to this here. Which pointed me to some great info.

http://stackoverflow.com/questions/8714899/zxing-autofocus-issue

My question is since I know that my device is going to be looking for smaller barcodes. What are some good steps I can take to help the camera find and focus these barcodes. I already know scanning them is possible. However, it took me forever because if the camera did focus the barcode it would only be for a split second which wasnt long eanough for the scan and then it would focus back out. 

Do I mess with optical zoom? Do I need to mess with the exposure at all? Should I set a manual focus? What do you guys think? As always I love the support on this site. 

-Nathan

[Nathan Kellert]

Also was just thinking about it. All of the tiny barcodes are black circular stickers. Perhapse there is a way to get android to recognize its shape and focus on it the same way the facial recognition works? Just an Idea. I really am kind of lost at where to start. 

[Sean Owen]

I would probably not change anything and let it continue to focus normally. You could try 'macro' mode, or setting the focus to minimum distance, but I think it will not work as well. The barcode needs to stay at least far enough to be in focus. So you can change the UI to make sure the user does that -- make the scan area appear to be smaller, for example.

Zoom makes sense, but digital zoom can cause image problems. Your devices don't have optical zoom. Exposure should not be a factor I think, but sure you can play with it. The Android app tends to over-expose to scan in dark conditions, but, will under-expose when the front-light is on, to even out the light level.