居中,裁剪,适合视频背景(在iframe中)到父元素

时间:2017-05-30 22:51:12

标签: jquery html css video iframe

给出以下标记:

<div class="viewport">
    <iframe src="youtube.com/blabla"></iframe>
</div>

以下css:

.viewport {
    height: 100vh;
    width: 100%;
}

iframe {
    position: absolute;
}

鉴于以下事实:

  • 在iframe中播放的视频的宽高比为16:9

是否有可能编写一个脚本,将iframe拉伸到大于父级的大小,以便iframe溢出,隐藏黑条?(是的,我知道它也会裁剪部分内容视频,但没关系)

以下是脚本必须解决的两个示例:

wide tall

在第一张图片中,黑条位于左侧和右侧。为了解决这个问题,脚本会将iframe拉伸得更宽更高,从而将视频拉伸到内部,直到黑条消失为止。我们丢失了视频的顶部和底部,但没关系。在第二张图片中,黑条位于顶部和底部,我们需要拉伸它并丢失视频的边缘。

这是我的注释尝试,但遗憾的是,代码并未涵盖所有情况。一旦我的视口的宽高比超过~2.1,黑条就会回来。随意废弃我的脚本。

    var block = $('.viewport');
    var block_h = block.outerHeight();
    var block_w = block.outerWidth();

    var ratio = block_w / block_h;

    // If viewport is landscape (black bars on left/right)
    if( ratio >= 1.77777778 ) {
        var video_w = (block_h * 16) / 9; // Get width of video within iframe
        var total_black_bar_w = block_w - video_w; // Black bar total width
        var new_iframe_w = (block_w + total_black_bar_w); // New width of the iframe needed to stretch the video wide enough to hide the black bars
        var adjustment_percentage = new_iframe_w / block_w; // If we adjusted the width by 10% for example, then we also need to apply that percentage to the height

        var new_iframe_h = (block_h * adjustment_percentage) + 30;

        var pull_left = total_black_bar_w / 2; // how far to pull left to center the iframe outside of the parent container
        var pull_top = (new_iframe_h - block_h) / 2; // same for top
    }
    // Portrait viewport (black bars on top/bottom)
    else {
        var video_h = (block_w * 9) / 16;
        var total_black_bar_h = block_h - video_h;
        var new_iframe_h = (block_h + total_black_bar_h);
        var adjustment_percentage = new_iframe_h / block_h;

        var new_iframe_w = (block_w * adjustment_percentage) + 30;

        var pull_left = total_black_bar_w / 2;
        var pull_top = (new_iframe_h - block_h) / 2;
    }

    block.find('iframe').css({
        'width': new_iframe_w,
        'height': new_iframe_h,
        'left': '-' + pull_left + 'px',
        'top': '-' + pull_top + 'px'
    });

1 个答案:

答案 0 :(得分:2)

它实际上比你的代码更简单。

始终保持iframe的比例,但只需调整整个事物(实际比例)以填充视口。

使用css定位/变换将其居中。

以下是一个较小视口(带红色边框)的示例,因此您可以看到它的实际效果。

jQuery(function($) {
  var viewport = $('.viewport'),
    frame = viewport.find('iframe'),
    frameRatio = 16 / 9;

  $(window).on('resize', function() {
    var width = viewport.outerWidth(),
      height = viewport.outerHeight(),
      ratio = width / height,
      targetWidth = width,
      targetHeight = height;

    if (ratio > frameRatio) {
      // viewport is wider than video
      // correct the height
      targetHeight = width / frameRatio;
    } else {
      // viewport is taller than video
      // correct the width
      targetWidth = height * frameRatio;
    }

    frame.css({
      width: targetWidth,
      height: targetHeight
    });
  }).trigger('resize');
});
.viewport {
  height: 50vh;
  width: 50vw;
  position: relative;
  border: 1px solid red;
  margin: 10% 25%;
}

iframe {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: -1;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<div class="viewport">
  <iframe src="//www.youtube.com/embed/1La4QzGeaaQ?autoplay=1"></iframe>
</div>

http://jsfiddle.net/agrxtwn7/embedded/上看到它(转到结果),因为似乎SO阻止了youtube嵌入播放