We are working a project for a client that is requesting barcodes no wider than 2.5 inches. The codes are comprised of 15 digit numbers, which, when using the suggested scale of "2.0" produces a barcode that is over 4 inches long. In order to get it down to the client spec, setting the scale to 1.3 shrinks it down to the specified size, but is not readable (as is expdected per the warning).

According to this page, http://www.adams1.com/39code.html, 15-digit barcodes should be readable as small as 1.65", but this is assuming we can set the width of the narrowest bar element to 7.5 mils.

Is a code that small even possible with this module?

Comments

mat miller’s picture

mat miller commented

Do you obliged to use Code 39? Any other linear barcode is not applied, like Code 128? Because Code 39 is discrete, so the intercharactergap will make the width of barcode image wider.

NathanSS’s picture

NathanSS commented

I'm doing a research for Code 39 and just run into this.

There is actually detailed description for Code 39 barcode sizing in ISO IEC 16388 Code 39 bar code symbology specification. The size is control a few aspects like module size, intercharacter gap, quiet zone(margins), etc.
In brief, you can get the minimum width of a Code 39 barcode with this formula:

Wmin= ( 13C + 45 ) X

C stands for the encoding character number, which is 15 in your case, W is the minimum Code 39 barcode width. From this simple equation, you will have your proper X (module width).

Regards,
Cathy

tr’s picture

tr commented
Issue summary: View changes
Status: Active » Closed (outdated)

Drupal 6 is long out of support.

This module is no longer supported. I suggest you try using the Barcodes module instead (https://www.drupal.org/project/barcodes)

Barcodes is very similar to this module, and is supported for Drupal 7, 8, and 9.