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WHAT THIS IS:

This program is a proof of concept for a UPC code reader based which uses the
 built in camera in series 60 devices.

BASIC DEMO:
- Print out the included test_upc.gif.  It will need to be about 6" wide.
- Install and run the included SIS file on your phone.
- Hold the test image about 8 inches away, under bright lighting without
        any shadows falling on it
- Make sure the whole barcode is visible and that there is only white space on
        the left and right sides
- Hold steady
- If the app crashes (it seems to every 20 seconds, i'm still working on this),
        restart.
- If you wish scan real UPC codes you will need to buy Nokia's CC-49 Macro Lens
        Expansys appears to be a good source of these in a number of countries.
        Your mileage may vary.   The built in camera can't focus on objects
        closer than about 5cm.  A regulation sized UPC code won't provide enough
        data to decode at that distance.

HOW IT WORKS:
- The program sets up a timer (PeriodicRunner.cpp) to either take a picture
        (when the phone is in use) or read an image file (on the simulator) every
        so often.  Currently this doesn't allow the app to be as responsive as
        it could be.
- The timers trigger the userdraw drawing function in BarcrAppview.cpp
- The first several events trigger the program to power the camera on, then
        set the lighting and quality modes (normal lighting, high quality), and
        then finally to start taking pictures.  Every time a picture is completed,
        another one is scheduled.
- Once a picture is available, it is run through a processing algorithm
- The processing algorithm only evaluates a 1 pixel band through the middle of
        the picture.  This is done so that no resizing, or aspect ratio
        correction are needed.
- The processing algorithm's first pass determines the average light and dark
        values of the image (the two most common values which are more than 20
        values apart on a 255 color greyscale range).  The average of that value
        then becomes the threshhold point.
- The processing algorithm makes its second pass, to locate the guard pattern.
- Starting from x position 0, a counter is incremented while it is finding light
        values (those above the threshhold point).  Once it hits a dark value,
        it keeps going until it finds another light value.  It does this to find        
	an alternating pattern of dark,light,dark of bars that are approximately
        the same length.  This is the left hand side guard pattern.
- Once the left hand side guard pattern has been identified, the right hand side
        pattern is searched for by searching from the right end of the image.
- When the guard patterns are identified, the average bar size is compared
        against the number of pixels between the guard patterns to see if
        we're likely to have a good match.
- If a good match is found, each digit is iterated on based on approximate start
        point, which is calculated from the end of the guard pattern and the bar
        width.
- Each digit is read and then compared to known bit patterns.  If there is no
        exact match for a number, the read is aborted.
- If the whole UPC is read without any errors, the final value is set on the
        class instance.
- The screen update function (called periodically) detects that a final value has
        been read, and stops calling the camera functions.  It displays the value.