|
|
Posted by larry on 10/22/06 17:09
iulian.ilea wrote:
> See this: http://www.fpdf.org/en/script/script5.php if you want to
> generate EAN13. The same algorithm I used in an ASP page and it worked.
> I printed the code on a laser printer and I it was readable from
> different scanners.
>
> I read above that maybe it will not be readable if the printed page is
> resized to fit the page. I THINK (I'm not sure) that will work because
> if an image with width of 250 is resized to 290 also the white and
> black stripes are resized equally. ...And THEORETICALLY it can be read.
>
> If you want to generate CODE 39, POSTNET, i25 barcodes:
> http://www.fpdf.org/en/script/index.php. Use the algorithm, you don't
> have to create pdf.
I was just posting from experience, that with a web based app you
mileage may vary - ultimately depending on the client. An example
would be one of the Linux epson drivers I've used does a wierd
dithering pattern when it prints bitmap images and totally screws up
barcodes (others are fine).
As for resizing, it also depends on the driver, the same scaling
algorithm that causes moire effects in dithered images can potentially
mess up barcode results. For the 250 to 290 that means 40 extra pixels
are inserted somewhere in your image width, the variation between thin
and thick bars (at least in code 3 of 9) is 1 to 3 (3 thin widths-1
thick) So if the browser fudges the image size there may be a problem
(as it is dealing wi ~72 dpi), if it gives it to the printer to resize
(~300dpi+) then it may be ok. You might have good results with a big
bitmap of of code scaled down to fit instead of the opposite as there
are more pixels to work with when printing)
And fpdf is great! (though watch for glitches on reading with IE, read
the FAQ)
Larry
Navigation:
[Reply to this message]
|