音乐褪色，在和淡入淡出效果。

Music fades in and fades out.

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您可以添加淡入淡出效果，使音频音轨的声音逐渐变大或变小，您还可以添加所有此类的特殊音效。

You can add fading effects, where the audio track gradually gets louder or quieter, or you can add special sound effects of all kinds.

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不仅如此，SVG的标记还可用于动态改变这些属性，因此可以沿着路径移动图形对象或者实现淡入淡出效果。

But why stop there? SVG also has tags that you can use to animate these properties, so you can move a graphics object along a path or fade it in or out.

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