|If you are just starting to use the Digit-Eyes products,
to learn about scanning.
Q. Where will I find UPC codes?
A. UPC codes are typically located where humans will not
find them. They are oblong, typically at least one
half inch / 1 cm in height and at least three times as
long as they are tall. You will find the bar codes are often
They will almost always be within 4 inches of the bottom of
the object because that is typically the maximum scan height
of a supermarket scanner.
- on boxes: away from the side that is opened.
- on cans with wrapped labels: adjacent to the seam
where the labels are joined
- on jars with a single label: as far away from the center
portion of the label as possible.
- on jars with two labels: on the back label
(typically the front label will be larger and may be more
elaborate in shape; back labels are typically smaller and
- on packages that are rectangular with small sides:
on the longer of the two small sides.
Q. What about soda cans and things that don't
have obvious labels?
A. It can be difficult to locate codes on items that are
round and that have continuous wrap labels or where the bar
code is part of the printing, as on a soda can. In this
case, it is typically necessary to scan the entire label
surface. We've found it convenient to do this by bracing the
bottom of the phone on a table and putting the can in front of
it. When the phone is scanning, it makes ticking noises. Each
time that there is a tick, turn the can 1/4 turn in front of
the camera. We have found that it rarely takes all four turns
to get a scan.
Q. Any tricks for scanning UPC / EAN codes?
A. When you are starting out, you should definitely try
sheets. These let you become familiar with the use of the
After getting comfortable with the practice exercises, try
a real item and start with a box. Initially, you will probably
find that it is usually easier to hold the phone steady and
turn the item slowly in front of it. One of our
customers reports that he got great results by using a holder
from his wife's plate collection, putting the phone in it and
turning the item in front of it. After you have more a
feel for the process, you'll probably want to transition to
holding the phone in your hand, but a hands-free approach can
be very useful when putting the groceries away!
Helpful Hint: If you are having
problems with the object, we recommend rotating it 90
degrees; the bar codes can be scanned from any angle and
rotating the object will cause the autofocus on the camera
Q. Where will I find the Digit-Eyes codes?
A. The Digit-Eyes codes are printed on address
labels before being stuck on the item that they label.
The labels can be quickly and easily found by touch; since you
are the person who sticks them on the item, you can put them
anyplace that seems convenient.
Q. Any tricks for scanning Digit-Eyes codes?
A. The codes will be captured faster if they are
relatively "square" to the phone. The camera
is in the upper right back of the iPhone or iPod when you are
holding the phone with the "home" button at the
bottom and facing you. Locate the code by touch
and put the lens of the camera on the code with the top and
right edges of the phone lined up with the top and right edges
of the label. Start the scanning operation and
lift the phone away from the code. It will make
the ticking noise until it recognizes the code. At that
time it will beep and vibrate to alert you that it has found
the code and is processing it. After identifying
the code, Digit-Eyes will either play the recorded content or
voice the text, if the label was pre-recorded or if it
includes text; otherwise, it will just invite you to record.
Some people find that aligning one of their fingers with
the camera and using it "point" to the code while
scanning is a helpful way to make sure the phone stays
aligned, but you will probably not need to do this after
you've had a little bit of practice.
Helpful hint: if VoiceOver persists in talking to you
with instructions when you want to record, you can quiet it
with a two-finger double tap.
Q. Does the orientation of the code or label
A. No. Digit-Eyes can read any code in any
Q. How far away should the camera be from the
item being scanned?
A. The answer to this question depends on which kind of
equipment you have: iPhone 3GS, iPhone 4/4S or iPad. All these
devices work fine, but we've found that the cameras behave
Generally for UPC codes and the standard Digit-Eyes tags,
- the 3GS works well about the distance of your hand (4 -
6 inches / 10 - 15 cm.) away. A quick way to gauge
this is by putting the edge of one hand on the object you
are scanning and putting your thumb in the
air. Touch your thumb with your camera hand
and you'll be about 6 inches / 12 cm from the
object. If you are using some of the very
large (4 - 8 inch / 10 - 20 cm) labels, you will need to
scan from a distance of about 36 inches / 1 meter.
- If you have the iPhone 4, you'll find that you can scan
at distances that range between 4 and 12 inches / 10 / 30
- If you have the iPad or iPhone 4S, both of which have
very good camera, the distances will range from between 4
and 20 inches / 10 / 50 cm.
- The scan distance on the iPhone 5 and the 4th genration
iPod will typically extend from 4 to 24 inches.
- The scan distance on the iPhone 5s and the 6 genration
iPod will typically extend from 4 to 30 inches.
Q. How much light is needed to scan?
A. The cameras on the the iPhones and iPad will read bar
codes in the same type of light that sighted people use for
reading. If you have an iPhone 4 or or later
model, Digit-Eyes will simply use the flash if it finds that
there is not enough light to scan. The iPhone 3gs and iPad do
not have a flash, so in this case, Digit-Eyes will warn you if
there is not enough light for it to be able to get a good
scan. As a general rule, cameras work better when there
is more light.
Q. Is reflection or shadow a problem?
A. Not generally. Bar codes are recognized
by the difference between light and dark, which is perceptible
to the camera in most cases. However, if you are
in a very extreme light environment, there are a couple of
possible issues. Please note that these are not common
- In extremely bright light and with very smooth surfaces,
the contrast may be such that the camera "sees"
a white reflection instead of the label.
- Likewise if you are in a very bright area and casting a
shadow on the label, it is possible that the
"light" portion of the label in shadow does not
appear very different to the camera from the dark portion
that is not in shadow.
If you are in doubt or having a lot of trouble, just turn
around; this will generally change the lighting environment
enough that the problem will be solved.
Q. Are there any tricks for getting the
autofocus to work?
A. We have found that the camera works best when you are
holding fairly still or when you are slowly moving the camera
away from the object (or the object away from the camera).
Q. This seems a little complicated. Does
it get easier?
A. Yes. Like any tool, there is a learning
curve. You will initially find using the text and voice
labels easier because it is simple to locate them by
touch. After you have used the Digit-Eyes for a day or
two, you'll find that it has become a habit and you won't
think about it any more.
Helpful Hint: If you are putting
groceries away and want to make the UPC codes easier to find
later, put a piece of scotch tape over it. Digit-Eyes will
easly read through the tape later and it is easy to find by
Q. Does it matter if the code is flat?
A. Not a lot, but if the camera can't manage to capture
an image of the whole label, Digit-Eyes won't be able to
resolve it. We'd suggest starting by flattening a couple
of wrappers and scanning them. Then move on to objects with
less regular surfaces.
Q. Curved surfaces seem harder to scan
A. You are correct; they are. This is because
there is some optical distortion because of the depth of the
curve. If you are having problems, try rotating either
the object or the phone (slowly) 90 degrees.
Q. Is the camera on the iPhone 4/4S and the
iPad different from that on the 3GS? How about the iPhone 5
and the 5th generation iPod? If so, how does this affect
A. Yes, the cameras are quite different.
- The camera on the 3GS is a 3-megapixel camera with
autofocus but no flash.
- The camera on the 4 is a 5-megapixel camera that has
flash built in and has considerably quicker autofocus
- The iPhone 5 has an 8-megapixel camera that works better
than the earlier cameras in low light situations.
The practical result is that you'll find that capturing the
bar code using an iPhone 6 is faster than on an iPhone 5, that capture on an iPhone 5 is
faster than on an iPhone 4 and
that capturing on an iPhone 4 is faster than with an iPhone
3GS. You'll also be able to capture codes from farther
away with the later phones because they have better cameras.
Please note, however, that Digit-Eyes was completely
developed and tested using the 3GS. As a result, the
Digit-Eyes app works excellently on all Apple platforms later than the iPhone 3Gs (June, 2010).
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