Python Requires Chilkat v11.7.0+

Get the Modules of a QR Code (Bit Matrix)

See more QR Code Examples

Demonstrates getting the QR code itself, as a grid of dark and light modules, to draw with something other than the built-in PNG and SVG output: on a canvas, in a PDF, on a display, or with a label printer language. With output.includeModuleData the response has symbols[0].moduleData, a bit matrix with one bit per module, each row starting on a new byte, most significant bit first, 1 for dark. The quiet zone is not part of the matrix. The example prints the symbol using two characters per module. Chilkat2-Python

import sys
import chilkat2

success = False

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

json = chilkat2.JsonObject()
json.UpdateString("payload.text","CHILKAT")
json.UpdateBool("output.includeModuleData",True)

fmt = chilkat2.Formats()
jsonOut = chilkat2.JsonObject()
success = fmt.QrCode("generate",json,jsonOut)
if (success == False):
    print(fmt.LastErrorText)
    sys.exit()

width = jsonOut.IntOf("symbols[0].moduleData.width")
height = jsonOut.IntOf("symbols[0].moduleData.height")
rowBytes = jsonOut.IntOf("symbols[0].moduleData.rowBytes")
print("kind: " + jsonOut.StringOf("symbols[0].moduleData.kind"))
print("modules: " + str(width) + " x " + str(height) + ", " + str(rowBytes) + " bytes per row")

# The matrix is height rows of rowBytes bytes.
bd = chilkat2.BinData()
success = bd.AppendEncoded(jsonOut.StringOf("symbols[0].moduleData.bytesBase64"),"base64")
if (success == False):
    print(bd.LastErrorText)
    sys.exit()

sbRow = chilkat2.StringBuilder()

mask = 128
for row in range(0,height):
    sbRow.Clear()
    for col in range(0,width):
        # The module at (col,row) is a bit of the byte at (row * rowBytes) + (col / 8).
        # The leftmost module of each byte is its most significant bit.
        if ((col % 8) == 0):
            mask = 128

        b = bd.GetByte((row * rowBytes) + (col / 8))
        if (((b / mask) % 2) == 1):
            sbRow.Append("##")
        else:
            sbRow.Append("  ")

        mask = mask / 2

    print(sbRow.GetAsString())

# The same symbol as the PNG that the call also returned:

# 

# Sample output:

# kind: bitMatrix
# modules: 21 x 21, 3 bytes per row
# ##############              ##############
# ##          ##      ####    ##          ##
# ##  ######  ##  ##  ####    ##  ######  ##
# ##  ######  ##  ##          ##  ######  ##
# ##  ######  ##  ##  ##  ##  ##  ######  ##
# ##          ##  ####  ##    ##          ##
# ##############  ##  ##  ##  ##############
#                 ####
# ##  ##########      ####    ##########
#     ####          ##  ########    ######
# ####  ########    ####  ##  ####      ####
#       ##  ##      ############    ####  ##
#   ######  ####  ######  ##    ##  ##
#                 ##  ##  ##    ##  ##    ##
# ##############        ##  ##    ##      ##
# ##          ##  ##  ##        ######  ####
# ##  ######  ##  ####  ##  ##    ##
# ##  ######  ##  ##  ############    ##
# ##  ######  ##  ##      ##  ####  ##
# ##          ##    ##  ########          ##
# ##############  ##      ##      ######