占位图生成

复制from PIL import Image, ImageDraw, ImageFont

# 生成 400x200 占位图，背景色 #3498db，文字 "400x200" 白色
width, height = 400, 200
bg_color = "#3498db"
text_color = "white"
text = f"{width}x{height}"

img = Image.new("RGB", (width, height), bg_color)
draw = ImageDraw.Draw(img)

# 使用默认字体，居中绘制文字
bbox = draw.textbbox((0, 0), text)
tw, th = bbox[2] - bbox[0], bbox[3] - bbox[1]
x = (width - tw) // 2
y = (height - th) // 2
draw.text((x, y), text, fill=text_color)

img.save("placeholder.png")
print("已生成 placeholder.png")

复制package main

import (
	"image"
	"image/color"
	"image/draw"
	"image/png"
	"log"
	"os"
)

func main() {
	width, height := 400, 200
	bg := color.RGBA{52, 152, 219, 255} // #3498db

	img := image.NewRGBA(image.Rect(0, 0, width, height))
	draw.Draw(img, img.Bounds(), &image.Uniform{bg}, image.Point{}, draw.Src)

	f, err := os.Create("placeholder.png")
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	if err := png.Encode(f, img); err != nil {
		log.Fatal(err)
	}
	log.Println("已生成 placeholder.png")
}

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

const width = 400;
const height = 200;
const canvas = createCanvas(width, height);
const ctx = canvas.getContext('2d');

// 填充背景
ctx.fillStyle = '#3498db';
ctx.fillRect(0, 0, width, height);

// 绘制居中文字
ctx.fillStyle = 'white';
ctx.font = '24px sans-serif';
const text = `${width}x${height}`;
const metrics = ctx.measureText(text);
const x = (width - metrics.width) / 2;
const y = (height + 24) / 2; // 近似垂直居中
ctx.fillText(text, x, y);

const buffer = canvas.toBuffer('image/png');
fs.writeFileSync('placeholder.png', buffer);
console.log('已生成 placeholder.png');