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Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.
Convert Image to ASCII Art in Python
Convert any image to ASCII art by resizing, converting to grayscale, and mapping pixel brightness to characters using Pillow.
from PIL import Image
import sys
ASCII_CHARS = "@%#*+=-:. "
def resize_image(image, new_width=100):
"""Resize image maintaining aspect ratio."""
width, height = image.size
ratio = height / width
new_height = int(new_width * ratio * 0.55) # 0.55 adjusts for font aspect ratio
return image.resize((…How to Convert Images Between Formats in Python
Use the Pillow library to open an image from one file format and save it to another, with error handling for missing files or conversion issues.
from PIL import Image
import sys
def convert_image_format(input_path, output_path):
try:
img = Image.open(input_path)
img.save(output_path)
print(f"Converted {input_path} to {output_path}")
except FileNotFoundError:
print(f"Error: File {input_path} not found")
sys.exit(…How to Generate Beautiful QR Codes with Embedded Logos in Python
Generate a high-error-correction QR code and paste a logo image in the center to create a branded, scannable QR code.
import qrcode
from PIL import Image
def generate_qr_with_logo(data, logo_path, output_path):
qr = qrcode.QRCode(
version=1,
error_correction=qrcode.constants.ERROR_CORRECT_H,
box_size=10,
border=4,
)
qr.add_data(data)
qr.make(fit=True)
qr_img = qr.make_image(fill_c…Automatically Generate Charts from CSV Files with One Command
Read a CSV file with headers, extract the first two numeric columns, and save a matplotlib line chart as a PNG image.
import csv
import sys
from pathlib import Path
import matplotlib.pyplot as plt
def generate_chart(csv_path: str) -> None:
"""Read a CSV file with headers and plot the first two numeric columns."""
data = []
with open(csv_path, 'r', newline='') as f:
reader = csv.reader(f)
headers = next(re…Create Mock Watermarked Image Bytes in Python Without PIL
Builds a mock image-like byte stream with an embedded watermark using only stdlib modules, for testing pipelines without PIL.
from io import BytesIO
import zlib
import struct
def create_watermarked_bytes(width: int, height: int, watermark: bytes) -> bytes:
"""Create a mock image-like byte stream with a watermark (no PIL)."""
header = struct.pack("<2I", width, height)
payload = watermark * max(1, (width * height // max(1, len(wa…Detect and Remove Blurry Images in Python with OpenCV
Automatically scan a directory of images, detect blur using Laplacian variance, and remove blurry images with a dry-run option for safety.
from pathlib import Path
import cv2
import numpy as np
def is_blurry(image_path, threshold=100.0):
"""
Detect if an image is blurry using Laplacian variance.
Returns True if blurry, False otherwise.
"""
img = cv2.imread(str(image_path), cv2.IMREAD_GRAYSCALE)
if img is None:
return True…Download Images from a Web Page Automatically in Python
Scrape all images from a webpage, filter by extension, and save them to a local folder using requests and BeautifulSoup.
import requests
from bs4 import BeautifulSoup
from urllib.parse import urljoin
import os
def download_images(url, output_folder="downloaded_images"):
"""Download all images from a given URL."""
os.makedirs(output_folder, exist_ok=True)
response = requests.get(url)
response.raise_for_status()
…Find Broken Image References Across a Website in Python
Crawl internal pages of a website, collect all image source URLs, then check each with HEAD requests to report any that return HTTP 4xx or connection errors.
import requests
from urllib.parse import urljoin, urlparse
from bs4 import BeautifulSoup
from concurrent.futures import ThreadPoolExecutor, as_completed
def find_all_links(base_url, max_pages=50):
visited, to_visit = set(), {base_url}
while to_visit and len(visited) < max_pages:
url = to_visit.pop()
…How to Batch Resize Images in Python with pathlib and Pillow
Batch resize all JPG images from a source folder and save to a destination folder using pathlib and Pillow.
from pathlib import Path
from PIL import Image
def batch_resize_images(src_dir: str, dest_dir: str, size: tuple[int, int] = (800, 600)) -> None:
src_path = Path(src_dir)
dest_path = Path(dest_dir)
dest_path.mkdir(parents=True, exist_ok=True)
for img_path in src_path.glob("*.jpg"):
if not …How to Build a Docker Image Tag Script in Python
Generate consistent Docker image tags from service names and versions with automatic normalization.
#!/usr/bin/env python3
"""Mock script for building docker image tags."""
def build_tag(service_name: str, version: str, registry: str = "docker.io") -> str:
"""Construct a docker image tag."""
safe_name = service_name.lower().replace("_", "-")
return f"{registry}/{safe_name}:{version}"
if __name__ == "…How to Create a File Organizer That Sorts Files Automatically in Python
A Python script that scans a given folder, categorizes files by extension (Images, Documents, Audio, Video, Archives, Misc), and moves them into subfolders automatically.
import os
import shutil
from pathlib import Path
FILE_CATEGORIES = {
"Images": [".jpg", ".jpeg", ".png", ".gif", ".bmp"],
"Documents": [".pdf", ".docx", ".txt", ".csv", ".xlsx"],
"Audio": [".mp3", ".wav", ".flac", ".aac"],
"Video": [".mp4", ".mkv", ".avi", ".mov"],
"Archives": [".zip", ".tar", ".g…How to Detect Unused Images in a Project with Python
A Python script that scans a website project folder, identifies all image files, and checks HTML/CSS/JS files to find which images are never referenced.
import os
import re
from pathlib import Path
def find_unused_images(project_path):
image_exts = {'.png', '.jpg', '.jpeg', '.gif', '.svg', '.webp'}
used_images = set()
all_images = set()
# Find all image files
for root, _, files in os.walk(project_path):
for file in files:
…How to Generate Thumbnails While Maintaining Aspect Ratio in Python
Resize images to fit within maximum dimensions while preserving the original aspect ratio using Pillow (PIL).
from PIL import Image
def thumbnail_with_aspect_ratio(image_path, output_path, max_width, max_height):
with Image.open(image_path) as img:
# Get original dimensions
width, height = img.size
# Calculate scaling ratio to fit within max dimensions
ratio = min(max_width / width, max_h…How to Generate a QR Code in Python
Generate a QR code image from a URL string using the qrcode library and save it as a PNG file.
import qrcode
# Data to encode
data = "https://www.example.com"
# Create QR code instance
qr = qrcode.QRCode(
version=1,
error_correction=qrcode.constants.ERROR_CORRECT_L,
box_size=10,
border=4,
)
# Add data to QR code
qr.add_data(data)
qr.make(fit=True)
# Create an image from the QR code
img = qr.…How to Hash Duplicate Photos and Delete Copies in Python
This script hashes image files in a directory using SHA-256 and deletes duplicate copies while keeping the first occurrence, ideal for cleaning up photo libraries.
from pathlib import Path
import hashlib
def file_hash(path, chunk_size=8192):
hasher = hashlib.sha256()
with open(path, "rb") as f:
for chunk in iter(lambda: f.read(chunk_size), b""):
hasher.update(chunk)
return hasher.hexdigest()
def delete_duplicate_photos(directory):
directory …How to Resize Hundreds of Images in Batch with Python
Resize every image in a folder to a target size using Pillow, creating a new subfolder for processed files.
import os
from PIL import Image
def resize_images_in_batch(directory, output_size=(800, 600)):
if not os.path.exists(directory):
print(f"Directory {directory} does not exist.")
return
output_dir = os.path.join(directory, "resized")
os.makedirs(output_dir, exist_ok=True)
for filename in…How to Strip EXIF Metadata from Images in Python
Remove EXIF metadata from image bytes using Pillow, with a mock JPEG generator for testing.
from PIL import Image
from PIL.ExifTags import TAGS
from io import BytesIO
import struct
def strip_exif(image_bytes, remove_metadata=True):
"""Remove EXIF metadata from image bytes."""
img = Image.open(BytesIO(image_bytes))
if remove_metadata:
# Clear all metadata
img.info.clear()
# Sa…How to Watch a Folder and Convert New Images in Python
Watch a folder for new files and mock-convert images by copying and renaming them in an output directory.
import time
import hashlib
from pathlib import Path
from datetime import datetime
def mock_convert_image(source: Path, dest_dir: Path) -> Path:
"""Mock image conversion: copy bytes and add .converted suffix."""
dest = dest_dir / f"{source.stem}.converted{source.suffix}"
dest.write_bytes(source.read_bytes(…How to automatically organize your Downloads folder by file type in Python
This script scans the Downloads folder and moves files into sub-folders based on their extensions (e.g., Images, Documents, Videos).
import os
import shutil
from pathlib import Path
def organize_downloads_folder(downloads_path=None):
if downloads_path is None:
downloads_path = str(Path.home() / "Downloads")
if not os.path.exists(downloads_path):
print(f"Path {downloads_path} does not exist.")
return
fi…How to Generate a Mock devcontainer.json Config in Python
Build a reproducible devcontainer.json file with Python, composing name, image, extensions, forwarded ports, and a post-create command as a dict.
import json
from pathlib import Path
def create_devcontainer_config(
image: str = "mcr.microsoft.com/devcontainers/python:3.11",
name: str = "python-dev-container",
ports: list[int] | None = None,
post_create: str | None = None,
) -> dict:
config = {
"name": name,
"image": image,
…Generate a docker-compose.yml with mock services in Python
Build a docker-compose.yml string from a Python dict of service names and images, then write it to a file.
import yaml
from pathlib import Path
def generate_mock_compose(services: dict) -> str:
compose = {
"version": "3.9",
"services": {}
}
for name, image in services.items():
compose["services"][name] = {
"image": image,
"container_name": f"mock-{name}",
…How to Build a Mock Trivy Image Scan Gate in Python
Simulate a Trivy image scan and enforce a security gate that fails the pipeline when vulnerabilities meet or exceed a severity threshold.
import json
import sys
def mock_trivy_scan(image_name, severity_threshold="HIGH"):
"""Simulate a Trivy image scan result."""
mock_vulnerabilities = [
{"ID": "CVE-2023-1234", "Severity": "HIGH", "Package": "openssl", "FixedVersion": "3.0.9"},
{"ID": "CVE-2024-5678", "Severity": "CRITICAL", "Pa…How to Mock Docker Image Non-Root User in Python
This Python class simulates Docker image layers and inspects whether the final user is a non-root user, returning UID, GID, and security status.
from pathlib import Path
class DockerImageMock:
def __init__(self, name, tag):
self.name = name
self.tag = tag
self.layers = []
self.user = "root"
def add_file(self, path, content):
self.layers.append({"file": path, "content": content})
def set_user(self, usernam…How to Mock Image Signing Cost in Python
Create a deterministic mock signing cost calculator that predicts resource usage for image signatures before real signing infrastructure is staged.
import math
import struct
def sign_image_cost(image_signature: bytes) -> int:
"""Deterministic mock signing cost based on image signature bytes."""
if not image_signature:
raise ValueError("Empty image signature")
digest = 0
for byte in image_signature:
digest = (digest * 31 + byte) &…Browse by section
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