文于止墨

显示音频波形

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文止墨
于 , ,

Audio Visualizer

等待上传…
查看代码
HTML
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Audio Visualizer Pro</title>
    <style>
        /* 全局重置与字体 */
        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        body {
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
            height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            /* 深色渐变背景 */
            background: linear-gradient(135deg, #0f0c29, #302b63, #24243e);
            color: #fff;
            overflow: hidden;
        }

        /* 玻璃拟态卡片容器 */
        .glass-card {
            background: rgba(255, 255, 255, 0.05);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 20px;
            padding: 40px;
            width: 90%;
            max-width: 800px;
            box-shadow: 0 15px 35px rgba(0, 0, 0, 0.6);
            display: flex;
            flex-direction: column;
            align-items: center;
            transition: transform 0.3s ease;
        }

        .glass-card:hover {
            transform: translateY(-5px);
        }

        h1 {
            font-weight: 200;
            letter-spacing: 2px;
            margin-bottom: 30px;
            text-transform: uppercase;
            background: linear-gradient(to right, #00c6ff, #0072ff);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            font-size: 1.8rem;
        }

        /* 自定义文件上传按钮 */
        .upload-btn-wrapper {
            position: relative;
            overflow: hidden;
            display: inline-block;
            margin-bottom: 25px;
        }

        .btn {
            border: 2px solid #00c6ff;
            color: #00c6ff;
            background-color: transparent;
            padding: 12px 30px;
            border-radius: 50px;
            font-size: 16px;
            font-weight: bold;
            cursor: pointer;
            transition: all 0.3s ease;
            text-transform: uppercase;
            letter-spacing: 1px;
            box-shadow: 0 0 10px rgba(0, 198, 255, 0.1);
        }

        .btn:hover {
            background-color: #00c6ff;
            color: #0f0c29;
            box-shadow: 0 0 20px rgba(0, 198, 255, 0.6);
        }

        .upload-btn-wrapper input[type=file] {
            font-size: 100px;
            position: absolute;
            left: 0;
            top: 0;
            opacity: 0;
            cursor: pointer;
            height: 100%;
            width: 100%;
        }

        /* 音频播放器美化 (尽可能) */
        audio {
            width: 100%;
            margin-bottom: 25px;
            border-radius: 10px;
            opacity: 0.9;
        }
        
        /* 去除 Chrome 默认播放器背景，使其更融合 (部分浏览器有效) */
        audio::-webkit-media-controls-panel {
            background-color: #e6e6e6;
        }

        /* Canvas 样式 */
        .canvas-container {
            width: 100%;
            position: relative;
            border-radius: 12px;
            overflow: hidden;
            border: 1px solid rgba(255,255,255,0.05);
            background: rgba(0,0,0,0.3);
            box-shadow: inset 0 0 30px rgba(0,0,0,0.8);
        }

        canvas {
            display: block;
            width: 100%;
            height: 250px;
        }

        /* 状态文字 */
        .status {
            margin-top: 15px;
            font-size: 0.9rem;
            color: rgba(255, 255, 255, 0.6);
            min-height: 20px;
        }
        
        /* 正在播放时的动画效果 */
        .playing-indicator {
            display: inline-block;
            width: 8px;
            height: 8px;
            background-color: #00ff88;
            border-radius: 50%;
            margin-right: 8px;
            box-shadow: 0 0 10px #00ff88;
            animation: pulse 1.5s infinite;
            opacity: 0;
        }
        
        .playing .playing-indicator {
            opacity: 1;
        }

        @keyframes pulse {
            0% { transform: scale(0.95); opacity: 0.7; }
            50% { transform: scale(1.2); opacity: 1; }
            100% { transform: scale(0.95); opacity: 0.7; }
        }
    </style>
</head>
<body>

    <div class="glass-card">
        <h1>Audio Visualizer</h1>
        
        <div class="upload-btn-wrapper">
            <button class="btn">选择音乐文件</button>
            <input type="file" id="fileInput" accept="audio/*" />
        </div>
        
        <audio id="audioPlayer" controls></audio>
        
        <div class="canvas-container">
            <canvas id="waveformCanvas"></canvas>
        </div>
        
        <div class="status" id="statusText">
            <span class="playing-indicator"></span><span id="textContent">等待上传...</span>
        </div>
    </div>

    <script>
        const fileInput = document.getElementById('fileInput');
        const audioPlayer = document.getElementById('audioPlayer');
        const canvas = document.getElementById('waveformCanvas');
        const ctx = canvas.getContext('2d');
        const statusTextContent = document.getElementById('textContent');
        const statusContainer = document.getElementById('statusText');

        let audioContext;
        let analyser;
        let source;
        let isInitialized = false;
        let animationId;

        function resizeCanvas() {
            canvas.width = canvas.parentElement.offsetWidth;
            canvas.height = canvas.parentElement.offsetHeight;
        }
        window.addEventListener('resize', resizeCanvas);
        resizeCanvas();

        function initAudioContext() {
            if (isInitialized) return;
            const AudioContext = window.AudioContext || window.webkitAudioContext;
            audioContext = new AudioContext();
            analyser = audioContext.createAnalyser();
            
            // 增加 FFT 大小以获得更平滑的波形
            analyser.fftSize = 2048; 
            
            source = audioContext.createMediaElementSource(audioPlayer);
            source.connect(analyser);
            analyser.connect(audioContext.destination);
            isInitialized = true;
        }

        fileInput.addEventListener('change', function(e) {
            const file = e.target.files[0];
            if (!file) return;

            const fileURL = URL.createObjectURL(file);
            audioPlayer.src = fileURL;
            statusTextContent.textContent = `正在播放: ${file.name}`;
            
            initAudioContext();
            
            if (audioContext.state === 'suspended') {
                audioContext.resume();
            }

            audioPlayer.play()
                .then(() => {
                    statusContainer.classList.add('playing');
                })
                .catch(err => {
                    console.log("Auto-play blocked");
                    statusTextContent.textContent = `准备就绪: ${file.name} (请点击播放)`;
                });

            // 如果之前有动画循环，先取消，防止叠加
            if(animationId) cancelAnimationFrame(animationId);
            drawWaveform();
        });

        audioPlayer.addEventListener('pause', () => {
            statusContainer.classList.remove('playing');
        });
        
        audioPlayer.addEventListener('play', () => {
            statusContainer.classList.add('playing');
            if (audioContext && audioContext.state === 'suspended') {
                audioContext.resume();
            }
        });

        function drawWaveform() {
            animationId = requestAnimationFrame(drawWaveform);

            if (!isInitialized) return;

            const bufferLength = analyser.fftSize;
            const dataArray = new Uint8Array(bufferLength);
            analyser.getByteTimeDomainData(dataArray);

            // 1. 清除画布，带一点透明度以产生"拖影"效果 (可选，这里用全清)
            ctx.clearRect(0, 0, canvas.width, canvas.height);

            // 2. 创建绚丽的线性渐变
            const gradient = ctx.createLinearGradient(0, 0, canvas.width, 0);
            gradient.addColorStop(0, '#00c6ff');    // 亮蓝
            gradient.addColorStop(0.5, '#0072ff');  // 深蓝
            gradient.addColorStop(1, '#00ff88');    // 荧光绿

            ctx.lineWidth = 3; // 线条加粗
            ctx.strokeStyle = gradient;
            
            // 3. 添加发光效果 (Glow Effect)
            ctx.shadowBlur = 10;
            ctx.shadowColor = "rgba(0, 198, 255, 0.5)";

            ctx.beginPath();

            const sliceWidth = canvas.width * 1.0 / bufferLength;
            let x = 0;

            for(let i = 0; i < bufferLength; i++) {
                const v = dataArray[i] / 128.0;
                const y = v * canvas.height / 2;

                // 使用贝塞尔曲线使波形更平滑
                if(i === 0) {
                    ctx.moveTo(x, y);
                } else {
                    // 简单的线性连接，对于高 fftSize 已经足够平滑
                    // 如果需要极致平滑可以使用 quadraticCurveTo
                    ctx.lineTo(x, y);
                }

                x += sliceWidth;
            }

            ctx.lineTo(canvas.width, canvas.height / 2);
            ctx.stroke();
            
            // 重置阴影，避免影响性能或其他绘制
            ctx.shadowBlur = 0;
        }
    </script>
</body>
</html>

下面的做法可以在用户同意后共享系统音频。由于涉及到屏幕共享，尽管此页面并不会向任何人（包括我）发送用户信息，但笔者认为仅给出代码比较好。

查看代码
HTML
<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>System Audio Visualizer</title>
    <style>
        /* --- 保持赛博朋克风格 --- */
        * { box-sizing: border-box; margin: 0; padding: 0; user-select: none; }
        
        body {
            font-family: 'Inter', sans-serif;
            height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            background: radial-gradient(circle at center, #000000 0%, #1a0b2e 100%);
            color: #fff;
            overflow: hidden;
        }

        .glass-card {
            background: rgba(255, 255, 255, 0.02);
            backdrop-filter: blur(20px);
            border: 1px solid rgba(255, 255, 255, 0.1);
            border-radius: 30px;
            padding: 40px;
            width: 90%;
            max-width: 700px;
            box-shadow: 0 0 80px rgba(138, 43, 226, 0.2);
            display: flex;
            flex-direction: column;
            align-items: center;
            text-align: center;
        }

        h1 {
            font-weight: 700;
            letter-spacing: 2px;
            margin-bottom: 10px;
            background: linear-gradient(to right, #ff00cc, #333399);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            text-transform: uppercase;
        }
        
        p.subtitle {
            color: #888;
            font-size: 0.9rem;
            margin-bottom: 30px;
        }

        /* 捕获按钮 */
        .capture-btn {
            background: linear-gradient(45deg, #ff00cc, #333399);
            border: none;
            padding: 15px 40px;
            border-radius: 50px;
            color: white;
            font-size: 1rem;
            font-weight: bold;
            cursor: pointer;
            box-shadow: 0 0 20px rgba(255, 0, 204, 0.4);
            transition: all 0.3s;
            margin-bottom: 20px;
        }

        .capture-btn:hover {
            transform: scale(1.05);
            box-shadow: 0 0 40px rgba(255, 0, 204, 0.6);
        }
        
        .capture-btn:disabled {
            background: #444;
            box-shadow: none;
            cursor: not-allowed;
            transform: none;
        }

        /* Canvas 容器 */
        .canvas-container {
            width: 100%;
            height: 250px;
            background: #000;
            border-radius: 16px;
            border: 1px solid rgba(255,255,255,0.1);
            box-shadow: inset 0 0 30px rgba(0,0,0,0.9);
            overflow: hidden;
            position: relative;
        }
        
        /* 网格背景 */
        .canvas-container::before {
            content: '';
            position: absolute;
            top: 0; left: 0; width: 100%; height: 100%;
            background: 
                linear-gradient(rgba(255,0,204,0.1) 1px, transparent 1px),
                linear-gradient(90deg, rgba(255,0,204,0.1) 1px, transparent 1px);
            background-size: 40px 40px;
            pointer-events: none;
        }

        canvas { width: 100%; height: 100%; }

        .status-text {
            margin-top: 20px;
            color: #aaa;
            font-size: 0.85rem;
        }
        
        .warn { color: #ff9900; }
    </style>
</head>
<body>

    <div class="glass-card">
        <h1>System Audio Visualizer</h1>
        <p class="subtitle">可视化电脑上的任何声音 (YouTube, Spotify 等)</p>
        
        <div class="canvas-container">
            <canvas id="waveformCanvas"></canvas>
        </div>

        <div class="status-text" id="statusText">准备就绪</div>
        <div class="status-text" id="statusText1">请选择共享整个屏幕，并勾选【分享系统音频】。</div>

        <br>

        <button class="capture-btn" id="startBtn">开始捕获系统音频</button>
    </div>

    <script>
        const startBtn = document.getElementById('startBtn');
        const canvas = document.getElementById('waveformCanvas');
        const ctx = canvas.getContext('2d');
        const statusText = document.getElementById('statusText');

        let audioContext;
        let analyser;
        let source;
        let animationId;
        let stream; // 保存媒体流以便停止

        // 调整画布大小
        function resizeCanvas() {
            canvas.width = canvas.parentElement.offsetWidth;
            canvas.height = canvas.parentElement.offsetHeight;
        }
        window.addEventListener('resize', resizeCanvas);
        resizeCanvas();

        startBtn.addEventListener('click', async () => {
            try {
                // 1. 请求屏幕共享，并强制要求音频
                stream = await navigator.mediaDevices.getDisplayMedia({
                    video: true, // 必须请求视频才能拿到系统音频（这是浏览器的限制）
                    audio: {
                        echoCancellation: false, // 关闭回声消除以获得更原始的音乐
                        noiseSuppression: false,
                        autoGainControl: false
                    }
                });

                // 2. 检查用户是否真的分享了音频
                const audioTracks = stream.getAudioTracks();
                if (audioTracks.length === 0) {
                    statusText.innerHTML = "<span class='warn'>❌ 未检测到音频！请刷新页面重试，并务必勾选【分享系统音频】。</span>";
                    // 停止所有轨道关闭共享图标
                    stream.getTracks().forEach(track => track.stop());
                    return;
                }

                statusText.textContent = "正在监听系统音频... (请在其他软件播放音乐)";
                startBtn.disabled = true;
                startBtn.textContent = "正在运行";

                // 3. 初始化 AudioContext
                if (!audioContext) {
                    audioContext = new (window.AudioContext || window.webkitAudioContext)();
                } else if (audioContext.state === 'suspended') {
                    audioContext.resume();
                }

                analyser = audioContext.createAnalyser();
                analyser.fftSize = 2048;

                // 4. 创建媒体流源
                source = audioContext.createMediaStreamSource(stream);
                source.connect(analyser);
                
                // ⚠️ 重要：不要连接到 destination (source.connect(audioContext.destination))
                // 因为声音本身就是系统发出的，如果这里再播放一次，会造成严重的重叠或回声。

                // 5. 监听流结束事件（比如用户点击了浏览器自带的“停止共享”）
                stream.getVideoTracks()[0].onended = () => {
                    statusText.textContent = "捕获已停止";
                    startBtn.disabled = false;
                    startBtn.textContent = "开始捕获系统音频";
                    cancelAnimationFrame(animationId);
                    ctx.clearRect(0, 0, canvas.width, canvas.height);
                };

                // 6. 开始绘图
                drawWaveform();

            } catch (err) {
                console.error("Error: " + err);
                statusText.textContent = "取消或发生错误: " + err.message;
            }
        });

        function drawWaveform() {
            animationId = requestAnimationFrame(drawWaveform);

            const bufferLength = analyser.fftSize;
            const dataArray = new Uint8Array(bufferLength);
            analyser.getByteTimeDomainData(dataArray);

            ctx.clearRect(0, 0, canvas.width, canvas.height);

            // 紫色系渐变
            const gradient = ctx.createLinearGradient(0, 0, canvas.width, 0);
            gradient.addColorStop(0, '#ff00cc');
            gradient.addColorStop(1, '#333399');

            ctx.lineWidth = 2.5;
            ctx.strokeStyle = gradient;
            ctx.shadowBlur = 15;
            ctx.shadowColor = "#ff00cc";

            ctx.beginPath();
            const sliceWidth = canvas.width * 1.0 / bufferLength;
            let x = 0;

            for(let i = 0; i < bufferLength; i++) {
                const v = dataArray[i] / 128.0;
                const y = v * canvas.height / 2;

                if(i === 0) ctx.moveTo(x, y);
                else ctx.lineTo(x, y);

                x += sliceWidth;
            }

            ctx.lineTo(canvas.width, canvas.height / 2);
            ctx.stroke();
            ctx.shadowBlur = 0;
        }
    </script>
</body>
</html>

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