Invisible schrieb:

>> http://www.herdsoft.com/ti/davinci4/examples/barcodecgi.cgi is 
>> convinced that it is a "Code 39" (aka "Code 3 of 9") barcode, and 
>> indeed correctly reads it as "UKM11001L3".
> 
> Really? (I can't even tell what language that page is in.)

That's German of course :-)

>> BTW, Wolfram is doing a poor job at generating Code 39 barcodes, as it 
>> uses different bar widths for the "frame" than for the "payload".
>>
>> (The Code 39 frame is usually interpreted as a leading and trailing 
>> asterisk (*) character, as it uses the same bar sequence.)
> 
> I especially love the way the bar widths don't appear to be multiples of 
> each other. I almost wonder if the image has been scaled down by 
> rounding each bar to a whole number of pixels, so some "thin" bars are 3 
> pixels and some are 4... It's very districting!

It is less surprising once you know that Code39 doesn't have fixed bar 
width ratios - just "narrow" and "wide" black and white bars (with each 
character having 3 "wide" and 6 "narrow" bars, and characters separated 
by another white bar; don't know if that is mandatorily narrow, though 
it seems common).


> Indeed, clicking on "PDF" and enlarging the image seems to make the 
> problem go away... How annoying!

Why not get one of those many Code39 TrueType fonts out there?

... or write a POV-Ray SDL script to generate barcode images :-)

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