imageutil

Image processing utilities supporting decode/encode, resize, crop, rotate, flip, filters, effects, watermark, composite, and histogram analysis.

Features

• Decode/Encode: JPEG, PNG, GIF, BMP, TIFF, WebP (decode only)
• Resize: nearest-neighbor, bilinear, CatmullRom, Lanczos, fit-with-padding
• Crop: rectangular, center, smart, aspect-ratio (9-grid anchor), circular, rounded corners
• Rotate 90/180/270, flip horizontal/vertical
• Adjust: brightness, contrast, gamma, saturation, hue, color temperature, tint
• Filters: box blur, gaussian blur, sharpen, edge detect (Sobel), emboss
• Effects: invert, sepia, posterize, threshold
• Watermark: image overlay (center/bottom-right/tiled) and text watermark
• Composite: blend modes, border, padding
• Info: dimensions, format detection, histogram and statistics

Key types

• Format -- image format (FormatJPEG, FormatPNG, FormatGIF, FormatBMP, FormatTIFF, FormatWebP)

Key functions

• DecodeFile(path), Decode(r), FromBytes(data) -- load images
• SaveJPEG, SavePNG, SaveByExtension -- write images
• ResizeBilinear, ResizeLanczos, ResizeNearest, Thumbnail, Fit
• Crop, CropCenter, CropSmart, CropToRatio, CircleCrop, RoundCorners
• Rotate90, FlipH, FlipV, Grayscale
• GaussianBlur, Sharpen, EdgeDetect, Invert, Sepia
• AddWatermark, AddTextWatermark
• FormatFromExtension(ext), ImageInfo(img)

Quick start

import (
    "image"
    "github.com/LingByte/ling-base/common/imageutil"
)

img, _, err := imageutil.DecodeFile("input.png")
if err != nil {
    log.Fatal(err)
}
resized := imageutil.ResizeLanczos(img, 200, 0) // width=200, auto height
rounded := imageutil.RoundCorners(resized, 24)
_ = imageutil.SaveJPEG(rounded, "output.jpg", 85)

License

MIT