📅  最后修改于: 2023-12-03 15:41:34.010000             🧑  作者: Mango
如果想要在网页中展示视频,有时会考虑将视频作为背景,那么如何在这种情况下实现视频缩放呢?
一般情况下,如果想要对图片进行缩放处理,可以使用CSS中的background-size属性,但是对于视频来说,这个属性是无效的。
一种解决方法是使用JavaScript来控制视频的大小和位置。具体实现步骤如下:
<video id="video" autoplay loop muted>
<source src="video.mp4" type="video/mp4">
</video>
#video {
position: fixed;
top: 0;
left: 0;
z-index: -1;
width: 100%;
height: 100%;
}
var video = document.getElementById('video');
function resizeVideo() {
var windowWidth = window.innerWidth;
var windowHeight = window.innerHeight;
var videoAspect = 1920 / 1080; // 视频宽高比为16:9
var windowAspect = windowWidth / windowHeight;
var scale = windowAspect > videoAspect ? windowHeight / 1080 : windowWidth / 1920;
var videoWidth = 1920 * scale;
var videoHeight = 1080 * scale;
video.style.width = videoWidth + 'px';
video.style.height = videoHeight + 'px';
video.style.left = (windowWidth - videoWidth) / 2 + 'px';
video.style.top = (windowHeight - videoHeight) / 2 + 'px';
}
window.addEventListener('resize', resizeVideo);
resizeVideo();
代码片段如下:
```html
<video id="video" autoplay loop muted>
<source src="video.mp4" type="video/mp4">
</video>
#video {
position: fixed;
top: 0;
left: 0;
z-index: -1;
width: 100%;
height: 100%;
}
var video = document.getElementById('video');
function resizeVideo() {
var windowWidth = window.innerWidth;
var windowHeight = window.innerHeight;
var videoAspect = 1920 / 1080; // 视频宽高比为16:9
var windowAspect = windowWidth / windowHeight;
var scale = windowAspect > videoAspect ? windowHeight / 1080 : windowWidth / 1920;
var videoWidth = 1920 * scale;
var videoHeight = 1080 * scale;
video.style.width = videoWidth + 'px';
video.style.height = videoHeight + 'px';
video.style.left = (windowWidth - videoWidth) / 2 + 'px';
video.style.top = (windowHeight - videoHeight) / 2 + 'px';
}
window.addEventListener('resize', resizeVideo);
resizeVideo();