Android Tutorial Barcode Scanning Observations

I have done some extensive barcode testing the last few days using a device with an 8 megapixel camera. I would like to share my obervations and hope many of you can debate, corroborate or add to them:

1. Dark black or blue bars on white paper (high contrast) is preferable.
2. Barcode must be on a perfectly flat surface without any undulations or even the slightest wrinkle.
3. For a one inch long barcode (I used code 128), placing the camera 4 to 5 inches away was the most I could get it to scan.
4. Barcode can be laminated with a transparent layer of tape.
5. Must have perfect overhead and surrounding lighting and no shadows.
6. Positioning and holding the camera must be very steady.
7. Always check the barcode scanned as a wrong barcode can be displayed and may surprise you.
8. Create barcodes with the highest quality print possible.
9. Commercially produced barcodes seem to work better than those from a printer.
10. Avoid barcodes generated from a copy. Originals work better.
11. Barcode scanning via a phone camera is no match for a laser scanner.

 

[carlospc]

Thanks for your observations!
Are you using a library to read barcodes?

Cheers!!!

 

[BarrySumpter]

Absolute Champion!

Thanks so much for posting your findings.

 

[Jost aus Soest]

Thanks a lot!

What does it mean "Always check the barcode scanned as a wrong barcode can be displayed and may surprise you"?
How do you do this by code?

 

[Penko]

Maybe he means to check it manually to verify it's okay.

 

[imbault]

Are you using a BA4 Library or an intent to the app "barcode Scanner"
Thks

Patrick

 

[mb1793]

is there a way i could pair a qr barcode with an image i have stored in my database ?

 

[colboy]

I work extensively with barcodes, so though I would add my responses based on my experience.

1. Dark black or blue bars on white paper (high contrast) is preferable.
Definitely black on white is the best option.

2. Barcode must be on a perfectly flat surface without any undulations or
even the slightest wrinkle.
Again flat is best.

3. For a one inch long barcode (I used code 128), placing the camera 4 to
5 inches away was the most I could get it to scan.
4-5 inches is pretty good for a camera. With laser scanners I've seen up to 13 feet, though this requires a much larger barcode.

4. Barcode can be laminated with a transparent layer of tape.
Laminating is usually OK, but can degrade performance of a poorly printed barcode

5. Must have perfect overhead and surrounding lighting and no shadows.
Never had any problems with a camera, other than low light.

6. Positioning and holding the camera must be very steady.
Once of the perils of camera scanning. A laser scanner always scans in an instant of a second and in my experience a camera always in excess of several seconds.

7. Always check the barcode scanned as a wrong barcode can be
displayed and may surprise you.
This should never happen with modern barcodes. Symbology 2 of 5 is terrible for this, but Code 128 and 39 this should never happen. These codes were built with check digits to prevent this.

8. Create barcodes with the highest quality print possible.
Anything more than 300dpi is probably overkill. The best barcode printers are usually 300dpi, with 200dpi as the norm. That being said some newer, higher dpi printers have just been launched.

9. Commercially produced barcodes seem to work better than those from a
printer.
I think you'd be hard pushed to tell the difference between a 300dpi laser print and a professional grade printed barcode.

10. Avoid barcodes generated from a copy. Originals work better.
Originals are always better, but you can generally produce a copy of a copy of a copy and still get a fairly reliable scan, if the original is good.

11. Barcode scanning via a phone camera is no match for a laser scanner.
Definitely, but then the cheapest new laser scanner is usually $300. If you need to scan a lot of codes in the course of a day, laser is the only way to go.

Hope this has been helpful.

Colin