Either set height property in codebehind .cs file

BCSBarcodeCtrl1.Width = 1;

Or add a tag directly

< img src="barcodesoft.ashx?s=code39&W=2

< img src="barcodesoft.ashx?s=code39ext&w=3

int width

Default value of width property is in pixel.
You can set it to whatever value you want.
This value sets the width of the entire bar code.

You can also setup width property through URL by setting "W":
<img src="Barcodesoft.ashx?s=code39&TEXT=1234&w=200>