Basic QR Code Generator — lets-plot

A QR (Quick Response) code visualization that encodes text or URL data into a square matrix barcode pattern. QR codes are two-dimensional barcodes that store information in a grid of black and white squares, readable by smartphones and dedicated scanners. This visualization is useful for generating scannable codes for quick data sharing and mobile access.

Basic QR Code Generator rendered with lets-plot

Python source (lets-plot)

""" anyplot.ai
qrcode-basic: Basic QR Code Generator
Library: letsplot 4.10.1 | Python 3.13.14
Quality: 86/100 | Updated: 2026-06-24
"""

import os

import pandas as pd
import qrcode
from lets_plot import (
    LetsPlot,
    aes,
    coord_fixed,
    element_rect,
    element_text,
    geom_raster,
    ggplot,
    ggsave,
    ggsize,
    labs,
    scale_fill_identity,
    theme,
    theme_void,
)


LetsPlot.setup_html()

# Theme-adaptive chrome tokens (Imprint palette)
THEME = os.getenv("ANYPLOT_THEME", "light")
PAGE_BG = "#FAF8F1" if THEME == "light" else "#1A1A17"
INK = "#1A1A17" if THEME == "light" else "#F0EFE8"
INK_SOFT = "#4A4A44" if THEME == "light" else "#B8B7B0"
INK_MUTED = "#6B6A63" if THEME == "light" else "#A8A79F"

# Generate QR code data
content = "https://pyplots.ai"
qr = qrcode.QRCode(version=1, error_correction=qrcode.constants.ERROR_CORRECT_M, box_size=1, border=4)
qr.add_data(content)
qr.make(fit=True)

# Convert QR matrix to dataframe — fill column used directly by scale_fill_identity
matrix = qr.get_matrix()
size = len(matrix)
rows = []
for y, row in enumerate(matrix):
    for x, cell in enumerate(row):
        rows.append({"x": x, "y": size - 1 - y, "fill": INK if cell else PAGE_BG})
df = pd.DataFrame(rows)

# Title length: 46 chars — shorter than 67-char baseline, use default 16px
title = "qrcode-basic · python · letsplot · anyplot.ai"

# Plot — square canvas: ggsize(600, 600) × scale=4 → 2400×2400 px (hard rule)
plot = (
    ggplot(df, aes(x="x", y="y", fill="fill"))
    + geom_raster()
    + scale_fill_identity()
    + coord_fixed()
    + labs(
        title=title,
        subtitle=f"Encoded: {content}  |  Error Correction: M (15%)",
        caption=f"Version {qr.version}  ·  {size}×{size} modules  ·  ECC Level M (15%)",
    )
    + ggsize(600, 600)
    + theme_void()
    + theme(
        plot_title=element_text(size=16, hjust=0.5, face="bold", color=INK),
        plot_subtitle=element_text(size=10, hjust=0.5, color=INK_SOFT),
        plot_caption=element_text(size=8, hjust=0.5, color=INK_MUTED),
        plot_background=element_rect(fill=PAGE_BG, color="#009E73", size=3),
        panel_background=element_rect(fill=PAGE_BG, color=PAGE_BG),
    )
)

# Save — square 2400×2400 px (PNG + HTML for interactive library)
ggsave(plot, f"plot-{THEME}.png", path=".", scale=4)
ggsave(plot, f"plot-{THEME}.html", path=".")

Part of Basic QR Code Generator on anyplot.ai.

Basic QR Code Generator — lets-plot

Python source (lets-plot)

Other implementations