A standard EAN-13 barcode visualization commonly used for retail products worldwide. The plot renders a scannable linear barcode encoding a 13-digit number with proper bar widths, guard patterns, and human-readable digits. This visualization is essential for product identification, inventory management, and point-of-sale systems.
""" anyplot.ai
barcode-ean13: EAN-13 Barcode
Library: matplotlib 3.10.9 | Python 3.13.13
Quality: 87/100 | Updated: 2026-05-21
"""
import os
import sys
sys.path = sys.path[1:] # prevent this file from shadowing the installed matplotlib package
import matplotlib.patches as patches
import matplotlib.pyplot as plt
# Theme
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"
# EAN-13 encoding tables
L_CODES = {
"0": "0001101",
"1": "0011001",
"2": "0010011",
"3": "0111101",
"4": "0100011",
"5": "0110001",
"6": "0101111",
"7": "0111011",
"8": "0110111",
"9": "0001011",
}
G_CODES = {
"0": "0100111",
"1": "0110011",
"2": "0011011",
"3": "0100001",
"4": "0011101",
"5": "0111001",
"6": "0000101",
"7": "0010001",
"8": "0001001",
"9": "0010111",
}
R_CODES = {
"0": "1110010",
"1": "1100110",
"2": "1101100",
"3": "1000010",
"4": "1011100",
"5": "1001110",
"6": "1010000",
"7": "1000100",
"8": "1001000",
"9": "1110100",
}
FIRST_DIGIT_PATTERN = {
"0": "LLLLLL",
"1": "LLGLGG",
"2": "LLGGLG",
"3": "LLGGGL",
"4": "LGLLGG",
"5": "LGGLLG",
"6": "LGGGLL",
"7": "LGLGLG",
"8": "LGLGGL",
"9": "LGGLGL",
}
# Data — 12-digit input; check digit auto-calculated
input_code = "400638133393"
total = sum(int(d) * (1 if i % 2 == 0 else 3) for i, d in enumerate(input_code))
check_digit = str((10 - (total % 10)) % 10)
full_code = input_code + check_digit # → "4006381333931"
ean_formatted = f"{full_code[0]} {full_code[1:7]} {full_code[7:]}" # "4 006381 333931"
# Encode EAN-13 bit pattern
lg_pattern = FIRST_DIGIT_PATTERN[full_code[0]]
barcode_pattern = "101" # start guard
for i, digit in enumerate(full_code[1:7]):
barcode_pattern += L_CODES[digit] if lg_pattern[i] == "L" else G_CODES[digit]
barcode_pattern += "01010" # center guard
for digit in full_code[7:13]:
barcode_pattern += R_CODES[digit]
barcode_pattern += "101" # end guard
# Guard bar bit indices: start (0–2), center (45–49), end (92–94)
guard_positions = set(range(3)) | set(range(45, 50)) | set(range(92, 95))
# Layout (data units — 1 unit = 1 module width)
quiet_zone = 9
start_x = quiet_zone
start_y = 7.0
bar_height = 14.0
guard_height = 17.0
total_modules = len(barcode_pattern) # 95
# Plot
fig, ax = plt.subplots(figsize=(8, 4.5), dpi=400, facecolor=PAGE_BG)
ax.set_facecolor(PAGE_BG)
# Draw barcode bars
for i, bit in enumerate(barcode_pattern):
if bit == "1":
is_guard = i in guard_positions
h = guard_height if is_guard else bar_height
y0 = start_y if is_guard else start_y + (guard_height - bar_height)
ax.add_patch(patches.Rectangle((start_x + i, y0), 1, h, linewidth=0, edgecolor="none", facecolor=INK))
# Style — human-readable digits below bars
digit_y = start_y - 0.5
digit_fs = 10
# First digit — sits outside the left quiet zone
ax.text(
start_x - 3.5,
digit_y,
full_code[0],
fontsize=digit_fs,
ha="center",
va="top",
fontfamily="monospace",
fontweight="bold",
color=INK,
)
# Left-side digits (positions 1–6); each digit spans 7 modules, after 3-bit start guard
for i, digit in enumerate(full_code[1:7]):
dx = start_x + 3 + (i + 0.5) * 7
ax.text(
dx,
digit_y,
digit,
fontsize=digit_fs,
ha="center",
va="top",
fontfamily="monospace",
fontweight="bold",
color=INK,
)
# Right-side digits (positions 7–12); start after start(3)+left(42)+center(5)=50 modules
for i, digit in enumerate(full_code[7:13]):
dx = start_x + 50 + (i + 0.5) * 7
ax.text(
dx,
digit_y,
digit,
fontsize=digit_fs,
ha="center",
va="top",
fontfamily="monospace",
fontweight="bold",
color=INK,
)
# Section labels — barcode anatomy guide below digit row
# Country (1–3): first digit at x=5.5, digits 2–3 at x=15.5, 22.5 → center=14.0
# Manufacturer (4–8): left digits 4–7 at x=29.5..50.5, right digit 8 at x=62.5 → center=46.0
# Product (9–12): right digits 9–12 at x=69.5..90.5 → center=80.0
# Check (13): right digit 13 at x=97.5
sections = [("Country (1–3)", 14.0), ("Manufacturer (4–8)", 46.0), ("Product (9–12)", 80.0), ("Check (13)", 97.5)]
for label, cx in sections:
ax.text(cx, digit_y - 2.0, label, fontsize=7, ha="center", va="top", color=INK_SOFT)
# Axis bounds and clean presentation
x_max = start_x + total_modules + quiet_zone # 9 + 95 + 9 = 113
y_max = start_y + guard_height + 5.0
ax.set_xlim(0, x_max)
ax.set_ylim(3.5, y_max)
ax.axis("off")
# Title
ax.text(
start_x + total_modules / 2,
start_y + guard_height + 2.0,
"barcode-ean13 · python · matplotlib · anyplot.ai",
fontsize=12,
ha="center",
va="bottom",
fontweight="medium",
color=INK,
)
# EAN-13 grouping format caption
ax.text(
start_x + total_modules / 2,
start_y + guard_height + 0.5,
ean_formatted,
fontsize=9,
ha="center",
va="bottom",
fontfamily="monospace",
color=INK_SOFT,
)
# Save
fig.subplots_adjust(left=0.03, right=0.97, top=0.97, bottom=0.03)
plt.savefig(f"plot-{THEME}.png", dpi=400, facecolor=PAGE_BG)
Part of EAN-13 Barcode on anyplot.ai.