Ruby Requires Chilkat v11.7.0+

QR Code with a Text Caption

See more QR Code Examples

Demonstrates printing a line of text under a QR code, such as the order number or the address the code holds, so that a person can read it too. render.text turns the caption on and gives its value, which is printable ASCII and is drawn in a built-in font that needs no font files. The caption can go above or below the symbol, be aligned left, center or right, and be scaled. Ruby

require 'chilkat'

success = false

#  This example requires the Chilkat API to have been previously unlocked.
#  See Global Unlock Sample for sample code.

json = Chilkat::CkJsonObject.new()
json.UpdateString("payload.text","https://www.chilkatsoft.com/order/12345")
json.UpdateInt("render.moduleSize",6)

#  The caption.  It need not be the same as the text in the QR code.
json.UpdateBool("render.text.enabled",true)
json.UpdateString("render.text.value","ORDER 12345")
#  position is "below" (the default) or "above".  alignment is "center" (the default), "left" or "right".
json.UpdateString("render.text.position","below")
#  Each dot of the caption's font is drawn this many pixels wide.
json.UpdateInt("render.text.scale",3)

json.UpdateString("output.path","qa_output/qr_caption.png")
json.UpdateBool("output.overwrite",true)
json.UpdateString("output.return","none")

fmt = Chilkat::CkFormats.new()
jsonOut = Chilkat::CkJsonObject.new()
success = fmt.QrCode("generate",json,jsonOut)
if (success == false)
    print fmt.lastErrorText() + "\n";
    exit
end

print "caption: " + jsonOut.stringOf("measurements[0].text") + "\n";
print "caption scale: " + jsonOut.IntOf("measurements[0].textScale").to_s() + "\n";
print "height added for the caption: " + jsonOut.IntOf("measurements[0].textBandPx").to_s() + " pixels" + "\n";
print "image: " + jsonOut.IntOf("measurements[0].canvasWidth").to_s() + " x " + jsonOut.IntOf("measurements[0].canvasHeight").to_s() + " pixels" + "\n";

#  The image written to qa_output/qr_caption.png:

#  

#  Sample output:

#  caption: ORDER 12345
#  caption scale: 3
#  height added for the caption: 21 pixels
#  image: 222 x 243 pixels