feat: add image watermark

2026-03-07 22:14:29 +08:00
parent 25d3b7d847
commit b091ad73d6
5 changed files with 455 additions and 0 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+node_modules/
 # ---> macOS
 # General
 .DS_Store
--- a/image-watermark/deno.json
+++ b/image-watermark/deno.json
@@ -0,0 +1,12 @@
+{
+  "tasks": {
+    "dev": "deno run --watch main.ts",
+    "watermark": "deno run --allow-read --allow-write --allow-env --allow-ffi main.ts",
+    "test": "deno test --allow-read --allow-write --allow-env --allow-ffi"
+  },
+  "nodeModulesDir": "auto",
+  "imports": {
+    "@std/assert": "jsr:@std/assert@1",
+    "sharp": "npm:sharp@^0.33.0"
+  }
+}
--- a/image-watermark/deno.lock
+++ b/image-watermark/deno.lock
@@ -0,0 +1,260 @@
+{
+  "version": "5",
+  "specifiers": {
+    "jsr:@std/assert@1": "1.0.13",
+    "jsr:@std/cli@*": "1.0.27",
+    "jsr:@std/internal@^1.0.6": "1.0.12",
+    "npm:sharp@0.33": "0.33.5"
+  },
+  "jsr": {
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+      "dependencies": [
+        "jsr:@std/internal"
+      ]
+    },
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+    },
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+    }
+  },
+  "npm": {
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+      "dependencies": [
+        "tslib"
+      ]
+    },
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+      "optionalDependencies": [
+        "@img/sharp-libvips-darwin-arm64"
+      ],
+      "os": ["darwin"],
+      "cpu": ["arm64"]
+    },
+    "@img/sharp-darwin-x64@0.33.5": {
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+      "optionalDependencies": [
+        "@img/sharp-libvips-darwin-x64"
+      ],
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+      "cpu": ["x64"]
+    },
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+      "cpu": ["x64"]
+    },
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+      "cpu": ["arm64"]
+    },
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+      "cpu": ["x64"]
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+        "@img/sharp-libvips-linuxmusl-x64"
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+      "dependencies": [
+        "@emnapi/runtime"
+      ],
+      "cpu": ["wasm32"]
+    },
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+      "os": ["win32"],
+      "cpu": ["x64"]
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+        "color",
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+        "@img/sharp-libvips-linux-s390x",
+        "@img/sharp-libvips-linux-x64",
+        "@img/sharp-libvips-linuxmusl-arm64",
+        "@img/sharp-libvips-linuxmusl-x64",
+        "@img/sharp-linux-arm",
+        "@img/sharp-linux-arm64",
+        "@img/sharp-linux-s390x",
+        "@img/sharp-linux-x64",
+        "@img/sharp-linuxmusl-arm64",
+        "@img/sharp-linuxmusl-x64",
+        "@img/sharp-wasm32",
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+    }
+  },
+  "remote": {
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+    "https://deno.land/x/imagescript@1.3.0/utils/wasm/svg.js": "f5c8a9d1977b51a7c07549ceb6bbbaca9497321a193f28b3dc229a42d91bcf14",
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+    "https://deno.land/x/imagescript@1.3.0/v2/ops/blur.mjs": "80716f1ffab8a2aeb54a036f583bf51a2b9dd37e005adc000add803df8e8a12f",
+    "https://deno.land/x/imagescript@1.3.0/v2/ops/color.mjs": "5e72cdcbf97dc939a2795223f01e3cb0544c0c56b03ea2aa026050df58348814",
+    "https://deno.land/x/imagescript@1.3.0/v2/ops/crop.mjs": "69431fa6f687fd9f0c31eff0ec27d7ac925275005e53a37f0c3fab4cc4d9a9ea",
+    "https://deno.land/x/imagescript@1.3.0/v2/ops/fill.mjs": "cf1b9488314753fbc9ebf03410ac74c2a34ea5a69fb6892cd6e8366cd1930d93",
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+    "https://deno.land/x/imagescript@1.3.0/v2/ops/resize.mjs": "814e78ebce8eaf8f1f918688db7b52a141405e06a36ed4b25d04413d69e7d17b",
+    "https://deno.land/x/imagescript@1.3.0/v2/ops/rotate.mjs": "a1b65616717bd2eed8db406affea3263b4674dada46b56441ef38167a187455d",
+    "https://deno.land/x/imagescript@1.3.0/v2/util/mem.mjs": "4968d400dae069b4bf0ef4767c1802fd2cc7d15d90eda4cfadf5b4cd19b96c6d"
+  },
+  "workspace": {
+    "dependencies": [
+      "jsr:@std/assert@1",
+      "npm:sharp@0.33"
+    ]
+  }
+}
--- a/image-watermark/main.ts
+++ b/image-watermark/main.ts
@@ -0,0 +1,133 @@
+#!/usr/bin/env -S deno run -A
+
+import sharp from "sharp";
+import { Buffer } from "node:buffer";
+import {parseArgs} from "jsr:@std/cli/parse-args";
+
+export interface WatermarkOptions {
+  /** 水印文字 */
+  text: string;
+  /** 字体大小 (默认 24) */
+  fontSize?: number;
+  /** 字体颜色 (默认白色，格式：#FFFFFF 或 rgba) */
+  color?: string;
+  /** 背景颜色 (默认透明，格式：#00000080 或 rgba) */
+  backgroundColor?: string;
+  /** 背景内边距 (默认 5) */
+  backgroundPadding?: number;
+  /** 距离右边距的像素 (默认 10) */
+  marginRight?: number;
+  /** 距离底边距的像素 (默认 10) */
+  marginBottom?: number;
+  /** 输出路径 (默认在原文件名后添加 _watermarked) */
+  outputPath?: string;
+}
+
+/**
+ * 在图片右下角添加文字水印
+ * @param inputPath 输入图片路径
+ * @param options 水印选项
+ */
+export async function addWatermark(
+  inputPath: string,
+  options: WatermarkOptions,
+): Promise<void> {
+  const {
+    text,
+    fontSize = 24,
+    color = "black",
+    backgroundColor,
+    backgroundPadding = 5,
+    marginRight = 10,
+    marginBottom = 10,
+  } = options;
+
+  let outputPath = options.outputPath;
+  if (!outputPath) {
+    const lastDot = inputPath.lastIndexOf(".");
+    outputPath = lastDot !== -1
+      ? `${inputPath.slice(0, lastDot)}_watermarked${inputPath.slice(lastDot)}`
+      : `${inputPath}_watermarked`;
+  }
+
+  // 获取原图信息
+  const metadata = await sharp(inputPath).metadata();
+  const width = metadata.width!;
+  const height = metadata.height!;
+
+  // 估算文字宽度（使用更精确的系数，根据常见字体调整）
+  // sans-serif 字体在 SVG 中的平均宽度系数约为 0.5-0.6
+  const textWidth = Math.ceil(text.length * fontSize * 0.55);
+  const textHeight = Math.ceil(fontSize * 0.9);
+
+  // 背景矩形尺寸
+  const bgWidth = textWidth + backgroundPadding * 2;
+  const bgHeight = textHeight + backgroundPadding * 2;
+
+  // 文字和背景位置（右下角对齐）
+  // text-anchor="end" 意味着文字的右边缘在指定的 x 坐标
+  const textX = width - marginRight - 20;
+  const textY = height - marginBottom;
+  
+  // 背景矩形的左上角坐标
+  // 背景右边缘与文字右边缘对齐
+  const rectX = textX - bgWidth + 20;
+  const rectY = textY - bgHeight + backgroundPadding + 2;
+
+  // 创建最终 SVG 水印
+  const svg = `<svg width="${width}" height="${height}" xmlns="http://www.w3.org/2000/svg">
+    ${backgroundColor ? `<rect x="${rectX}" y="${rectY}" width="${bgWidth}" height="${bgHeight}" fill="${backgroundColor}" rx="4"/>` : ""}
+    <text x="${textX}" y="${textY}" font-family="sans-serif" font-size="${fontSize}" fill="${color}" text-anchor="end" dominant-baseline="alphabetic">${escapeXml(text)}</text>
+  </svg>`;
+
+  // 将 SVG 水印叠加到原图
+  await sharp(inputPath)
+    .composite([
+      {
+        input: Buffer.from(svg),
+        top: 0,
+        left: 0,
+      },
+    ])
+    .toFile(outputPath);
+
+  console.log(`Added watermark: ${outputPath}`);
+}
+
+/**
+ * 转义 XML 特殊字符
+ */
+function escapeXml(str: string): string {
+  return str
+    .replace(/&/g, "&amp;")
+    .replace(/</g, "&lt;")
+    .replace(/>/g, "&gt;")
+    .replace(/"/g, "&quot;")
+    .replace(/'/g, "&apos;");
+}
+
+if (import.meta.main) {
+  const flags = parseArgs(Deno.args, {
+      boolean: ["help"],
+      string: ["watermark"],
+  });
+
+  const watermarkText = flags.watermark;
+  const imagePaths = flags._;
+
+  if (!watermarkText || imagePaths.length == 0) {
+    console.log("Usage: deno run -A main.ts --watermark 'watermark' <FILES>");
+    console.log("Example: deno run -A main.ts --watermark '© 2026 MyName' image.jpg");
+    Deno.exit(1);
+  }
+
+  for (const imagePath of imagePaths) {
+    await addWatermark(imagePath+'', {
+      fontSize: 32,
+      text: watermarkText,
+      color: 'black',
+      backgroundPadding: 2,
+      backgroundColor: 'white' 
+    });
+  }
+}
--- a/image-watermark/main_test.ts
+++ b/image-watermark/main_test.ts
@@ -0,0 +1,49 @@
+import { assertEquals } from "@std/assert";
+import { addWatermark } from "./main.ts";
+
+Deno.test("addWatermark - should add watermark to image", async () => {
+  const { default: sharp } = await import("sharp");
+  
+  // 创建测试图片 (200x200 红色方块)
+  const testImagePath = "/tmp/test_image.png";
+  await sharp({
+    create: {
+      width: 200,
+      height: 200,
+      channels: 3,
+      background: { r: 255, g: 0, b: 0 },
+    },
+  }).png().toFile(testImagePath);
+  
+  const outputPath = "/tmp/test_image_watermarked.png";
+  
+  try {
+    // 添加水印（带背景色）
+    await addWatermark(testImagePath, {
+      text: "Test Watermark",
+      fontSize: 16,
+      color: "white",
+      backgroundColor: "#80000000",
+      backgroundPadding: 5,
+      marginRight: 10,
+      marginBottom: 10,
+      outputPath,
+    });
+    
+    // 验证输出文件存在
+    const stat = await Deno.stat(outputPath);
+    assertEquals(stat.isFile, true);
+  } finally {
+    // 清理
+    try {
+      await Deno.remove(testImagePath);
+    } catch {
+      // Ignore
+    }
+    try {
+      await Deno.remove(outputPath);
+    } catch {
+      // Ignore
+    }
+  }
+});