JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://content.jwplatform.com/libraries/ntEbmj0B.js"></script>
<div class="block">
  <div class="videoWrapper">
    <iframe id="vimeo_player" src="https://player.vimeo.com/video/181644714?autoplay=1&loop=1&player_id=vimeo_player&title=0&byline=0&portrait=0" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
  </div>

  <div class="block">
    <div class="videoWrapper">
      <iframe id="vimeo_player" src="https://player.vimeo.com/video/181644714?autoplay=1&loop=1&player_id=vimeo_player&title=0&byline=0&portrait=0" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
    </div>


    <div class="block">
      <div class="videoWrapper">
        <iframe id="vimeo_player" src="https://player.vimeo.com/video/181644714?autoplay=1&loop=1&player_id=vimeo_player&title=0&byline=0&portrait=0" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
      </div>


      <div class="block">
        <div class="videoWrapper">
          <iframe id="vimeo_player" src="https://player.vimeo.com/video/181644714?autoplay=1&loop=1&player_id=vimeo_player&title=0&byline=0&portrait=0" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
        </div>


        <div class="block">
          <div class="videoWrapper">
            <iframe id="vimeo_player" src="https://player.vimeo.com/video/181644714?autoplay=1&loop=1&player_id=vimeo_player&title=0&byline=0&portrait=0" width="640" height="360" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe>
          </div>

          <div class="block">
            <div class="videoWrapper">
              <iframe id="vimeo_player" src="https://player.vimeo.com/video/181644714?autoplay=1&loop=1&player_id=vimeo_player&title=0&byline=0&portrait=0" width="640" height="360" frameborder="0"...

CSS

.block {
  width: 100%;
  padding-top: 200px;
  padding-bottom: 200px;
  height: 100%;
}

.videoWrapper {}

JavaScript

function onScrollVideo() {
  updateVideo();
}

function updateVideo() {

  var windowHeight = $(window).height(),

    gridTop = 200,
    gridBottom = 1000;

  $('.jwplayer').each(function() {
    var thisTop = $(this).offset().top - $(window).scrollTop(),
      playerID = $(this).prop('id');

    if (thisTop > gridTop && (thisTop + $(this).height()) < gridBottom) {
      jwplayer(playerID).play();

    } else {
      jwplayer(playerID).pause(true);

    }

  });

}
window.addEventListener('scroll', onScrollVideo, false);