图片水印

复制from PIL import Image, ImageDraw, ImageFont

# 文字水印：平铺 + 透明度
img = Image.open('input.jpg').convert('RGBA')
overlay = Image.new('RGBA', img.size, (0, 0, 0, 0))
draw = ImageDraw.Draw(overlay)
font = ImageFont.truetype('arial.ttf', 36)

# 半透明灰色文字
text = 'Watermark'
fill = (128, 128, 128, 60)  # RGBA，A=60/255

# 平铺：每 200px 重复
for y in range(0, img.height, 200):
    for x in range(0, img.width, 200):
        draw.text((x, y), text, font=font, fill=fill)

result = Image.alpha_composite(img, overlay)
result.save('output.png')

复制package main

import (
	"image"
	"image/color"
	"image/draw"
	"image/jpeg"
	"image/png"
	"log"
	"os"
	"golang.org/x/image/font"
	"golang.org/x/image/font/basicfont"
	"golang.org/x/image/math/fixed"
)

func main() {
	src, err := os.Open("input.jpg")
	if err != nil {
		log.Fatal(err)
	}
	defer src.Close()

	img, _, err := image.Decode(src)
	if err != nil {
		log.Fatal(err)
	}

	// 创建半透明覆盖层
	overlay := image.NewRGBA(img.Bounds())
	draw.Draw(overlay, overlay.Bounds(), img, image.Point{}, draw.Src)

	// 平铺文字水印（简化：仅左上角一个）
	col := color.RGBA{128, 128, 128, 60}
	point := fixed.Point26_6{fixed.I(50), fixed.I(100)}
	d := &font.Drawer{
		Dst:  overlay,
		Src:  image.NewUniform(col),
		Face: basicfont.Face7x13,
		Dot:  point,
	}
	d.DrawString("Watermark")

	out, _ := os.Create("output.png")
	defer out.Close()
	png.Encode(out, overlay)
}

复制const { createCanvas, loadImage, registerFont } = require('canvas');
const fs = require('fs');

async function addWatermark() {
  const img = await loadImage('input.jpg');
  const canvas = createCanvas(img.width, img.height);
  const ctx = canvas.getContext('2d');

  // 绘制原图
  ctx.drawImage(img, 0, 0);

  // 文字水印：平铺 + 透明度
  ctx.font = '36px Arial';
  ctx.fillStyle = 'rgba(128, 128, 128, 0.24)';  // 60/255 ≈ 0.24
  ctx.textAlign = 'left';

  const text = 'Watermark';
  for (let y = 0; y < img.height; y += 200) {
    for (let x = 0; x < img.width; x += 200) {
      ctx.fillText(text, x, y);
    }
  }

  const buffer = canvas.toBuffer('image/png');
  fs.writeFileSync('output.png', buffer);
}

addWatermark().catch(console.error);