pillow-image-editor

Pillow Image Editor

Programmatic image editing via Pillow (PIL fork). Pillow 10.4+ is installed in the system Python.

When to use

• Resize / crop / rotate / flip / transpose
• Format conversion (PNG, JPEG, WebP, GIF, AVIF, TIFF, BMP)
• Compression / quality tuning / file-size reduction
• Filters: blur, sharpen, edge detection, emboss, contour
• Adjustments: brightness, contrast, saturation, color balance
• Compositing: paste, alpha blend, transparency, masks
• Annotation: draw text, shapes, lines, watermarks, logos
• EXIF: read, strip, or preserve metadata
• Thumbnails, ICO/favicon generation, sprite sheets
• Batch processing a folder of images

For generating images from prompts, prefer gemini-imagegen or kie-ai. This skill is for deterministic pixel-level edits to existing files.

Quick start

Pillow is already installed. Import like this:

from PIL import Image, ImageDraw, ImageFilter, ImageOps, ImageEnhance, ImageFont, ExifTags

Minimal operations

# Resize (preserve aspect ratio, fit within box)
img = Image.open("in.jpg")
img.thumbnail((1200, 1200))  # modifies in place, keeps aspect
img.save("out.jpg", quality=85, optimize=True)

# Hard resize to exact dimensions
img.resize((800, 600), Image.Resampling.LANCZOS).save("out.png")

# Crop (left, upper, right, lower)
img.crop((100, 50, 900, 650)).save("cropped.png")

# Rotate / flip
img.rotate(90, expand=True).save("rotated.png")
ImageOps.mirror(img).save("flipped_horizontal.png")
ImageOps.flip(img).save("flipped_vertical.png")

# Convert format / color mode
Image.open("in.png").convert("RGB").save("out.jpg", quality=90)  # drop alpha for JPEG

Filters & adjustments

from PIL import ImageFilter, ImageEnhance

img.filter(ImageFilter.GaussianBlur(radius=5))
img.filter(ImageFilter.UnsharpMask(radius=2, percent=150, threshold=3))
img.filter(ImageFilter.FIND_EDGES)

ImageEnhance.Brightness(img).enhance(1.2)   # >1 brighter, <1 darker
ImageEnhance.Contrast(img).enhance(1.5)
ImageEnhance.Color(img).enhance(0.0)        # 0.0 = grayscale, 1.0 = original
ImageEnhance.Sharpness(img).enhance(2.0)