Add a Barcode to Your Own Form

You need the PixelBinary download and a PDF editor that can do three things: add form fields, use an installed font in a field, and add JavaScript to the document. The steps below name the places in Adobe Acrobat Pro; other editors have the same settings under other names.

1. Install the fonts

Unzip the download and install both files in the fonts folder (on Windows: right-click > Install). Restart your PDF editor so it sees them.

Font	A filled square is	Used by
PixelBinary-010101	1.0 × 1.0 of the font size	Adobe Acrobat and Acrobat Reader
PixelBinary Tall135	1.35 × 1.35 of the font size	Viewers built on pdf.js (Firefox, DocuWrit)

2. The field people type into

Any text field will do. In this guide it is called Text.

3. Two fields where the barcode goes

Add a text field named QR where the barcode should appear, 200 × 200 points (about 2.8 inches or 7 cm square):

Setting	Value	In Acrobat Pro
Read only	on	General tab
Multi-line	on	Options tab
Scroll long text, check spelling	off	Options tab
Font	PixelBinary-010101	Appearance tab
Font size	any fixed size, for example 5 (the script changes it; not “Auto”)	Appearance tab
Border and fill colour	none	Appearance tab
Alignment	left	Options tab

Then add a second field of the same size in exactly the same place, named QRTall, with the same settings except: font PixelBinary Tall135, font size 2. Leave it empty.

The names are yours to choose, but the second field must be the first name plus Tall. Why two fields: see Which PDF programs run it.

4. Add the script to the document

Open PixelBinary-script.js from the download in a text editor and copy all of it. In Acrobat Pro open the JavaScript tool (All tools > Use JavaScript; in older versions Tools > JavaScript), choose Document JavaScripts, type a name such as PixelBinary, choose Add, replace everything Acrobat put into the editor with what you copied, and confirm.

5. Redraw the barcode when the text changes

Open the properties of the field Text. On the Validate tab choose Run custom validation script and enter one line:

For a	Script
QR code	PixelBinary.show(this, "QR", PixelBinary.qr(event.value));
Data Matrix code	PixelBinary.show(this, "QR", PixelBinary.datamatrix(event.value));

"QR" is the name of your barcode field. Save the form, type something into Text and leave the field: the barcode appears.

Good to know

• Size. The script picks the largest font size at which the whole code fits. It assumes fields of 200 points: for another size, change box: 196 near the top of the glue part of the script to your field size less 4.
• Longer texts make smaller squares. Keep the text short, or make the field bigger. The example limits the text to 200 characters; set a character limit on your own text field too.
• White margin. The script adds the empty margin a scanner needs. Do not put anything right against the field.
• A barcode from several fields. Build the text yourself: PixelBinary.show(this, "QR", PixelBinary.qr(this.getField("Name").value + "|" + this.getField("ID").value)); — put the line into the Validate script of each field involved, using event.value for the field the script belongs to.
• Starting barcode. A new form shows a barcode only after the text has been changed once. Type the starting text and save the form before you hand it out.
• Scan it. Before you rely on a form, scan what it produces with the scanner or the phone that will be used.

Next: Which PDF programs run it.