當前位置:
首頁 >
前端技术
> javascript
>内容正文
javascript
JavaScript 清除图片背景颜色 使之透明
生活随笔
收集整理的這篇文章主要介紹了
JavaScript 清除图片背景颜色 使之透明
小編覺得挺不錯的,現在分享給大家,幫大家做個參考.
主要JS
/**清除圖片背景顏色 **/ function removeImgBg(img) {//背景顏色 白色const rgba = [255, 255, 255, 255];// 容差大小const tolerance = 60;var imgData = null;const [r0, g0, b0, a0] = rgba;var r, g, b, a;const canvas = document.createElement('canvas');const context = canvas.getContext('2d');const w = img.width;const h = img.height;canvas.width = w;canvas.height = h;context.drawImage(img, 0, 0);imgData = context.getImageData(0, 0, w, h);for (let i = 0; i < imgData.data.length; i += 4) {r = imgData.data[i];g = imgData.data[i + 1];b = imgData.data[i + 2];a = imgData.data[i + 3];const t = Math.sqrt((r - r0) ** 2 + (g - g0) ** 2 + (b - b0) ** 2 + (a - a0) ** 2);if (t <= tolerance) {imgData.data[i] = 0;imgData.data[i + 1] = 0;imgData.data[i + 2] = 0;imgData.data[i + 3] = 0;}}context.putImageData(imgData, 0, 0);const newBase64 = canvas.toDataURL('image/png');img.src = newBase64; }測試示例:
<!DOCTYPE html> <html><head><title> new document </title><meta name="generator" content="editplus" /><meta name="author" content="" /><meta name="keywords" content="" /><meta name="description" content="" /><style>html,body {background: #c7bbbb;text-align: center;}</style> </head><body><img id="img"src='https://img-blog.csdnimg.cn/2022020110394629157.png'><script>setTimeout(() => {removeImgBg(document.getElementById('img'));}, 3000);/**清除圖片背景顏色 **/function removeImgBg(img) {//背景顏色 白色const rgba = [255, 255, 255, 255];// 容差大小const tolerance = 60;var imgData = null;const [r0, g0, b0, a0] = rgba;var r, g, b, a;const canvas = document.createElement('canvas');const context = canvas.getContext('2d');const w = img.width;const h = img.height;canvas.width = w;canvas.height = h;context.drawImage(img, 0, 0);imgData = context.getImageData(0, 0, w, h);for (let i = 0; i < imgData.data.length; i += 4) {r = imgData.data[i];g = imgData.data[i + 1];b = imgData.data[i + 2];a = imgData.data[i + 3];const t = Math.sqrt((r - r0) ** 2 + (g - g0) ** 2 + (b - b0) ** 2 + (a - a0) ** 2);if (t <= tolerance) {imgData.data[i] = 0;imgData.data[i + 1] = 0;imgData.data[i + 2] = 0;imgData.data[i + 3] = 0;}}context.putImageData(imgData, 0, 0);const newBase64 = canvas.toDataURL('image/png');img.src = newBase64;}</script> </body></html>清除前:?
清除后:?
總結
以上是生活随笔為你收集整理的JavaScript 清除图片背景颜色 使之透明的全部內容,希望文章能夠幫你解決所遇到的問題。
- 上一篇: HTML 元素内部添加预加载
- 下一篇: [转]HTTP/3 未来可期?