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Google AMP - Video

Amp-video in amp is a standard html5 video used to play direct video embeds. In this chapter, let us understand how to work with and use amp-video.

To work with amp-video we need to add following script −

<script async custom-element = "amp-video" 
   src = "https://cdn.ampproject.org/v0/amp-video-0.1.js">
</script>

Amp-video has src attribute which has the video resource to be loaded, which is lazily loaded by amp at runtime. Besides, all the features are almost same as html5 video tag.

The following are the nodes that are to be added to amp video −

Source − You can add different media files to be played using this tag.

Track − This tag lets you enable the subtitles for the video.

Placeholder − This placeholder tag will show content before the video starts.

Fallback − This tag will be called when the browser does not support HTML5 video.

Format of amp-video tag

The format for amp-video tag is shown here −

<amp-video controls width = "640" height = "360" 
   layout = "responsive" poster = "images/videoposter.png">
   <source src = "video/bunny.webm" type = "video/webm" />
   <source src = "video/samplevideo.mp4" type = "video/mp4" />
   
   <span fallback>
      <p>This browser does not support the video element.</p>
   </span>
</amp-video>

Let us understand amp-video using a working example as shown below −

Example

<!doctype html>
<html amp lang = "en">
   <head>
      <meta charset = "utf-8">
      <script async src = "https://cdn.ampproject.org/v0.js"></script>
      <title>Google AMP - Amp Video</title>
      <pnk rel = "canonical" href =  "http://example.ampproject.org/article-metadata.html">
      <meta name = "viewport" content = "width = device-width, minimum-scale = 1,initial-scale=1">

      <style amp-boilerplate>
         body {
            -webkit-animation:
            -amp-start 8s steps(1,end) 0s 1 normal both;-moz-animation:
            -amp-start 8s steps(1,end) 0s 1 normal both;-ms-animation:
            -amp-start 8s steps(1,end) 0s 1 normal both;animation:
            -amp-start 8s steps(1,end) 0s 1 normal both}
         @-webkit-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@-moz-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@-ms-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@-o-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}
      </style>
      <noscript>
         <style amp-boilerplate>
            body {
               -webkit-animation:none;
               -moz-animation:none;
               -ms-animation:none;
               animation:none
            }
         </style>
      </noscript>

      <script async custom-element = "amp-video" 
         src = "https://cdn.ampproject.org/v0/amp-video-0.1.js">
      </script>
   </head>
   <body>
      <h3>Google AMP - Amp Video</h3>
      <amp-video controls
         width = "640"
         height = "360"
         layout = "responsive"
         poster = "images/videoposter.png">
         <source src = "video/bunny.webm" type = "video/webm" />
         <source src = "video/samplevideo.mp4" type = "video/mp4" />
         
         <span fallback>
            <p>This browser does not support the video element.</p>
         </span>
      </amp-video>
   </body>
</html>

Output

The output of the code given above is as shown below −

Attributes Available for amp-video

The attributes available for amp-video are psted in the table here −

Sr.No	Attributes & Description
1	src If the <source> node is not present, then src has to be specified and it has be https:// url.
2	poster The poster takes img url which is displayed before the video starts.
3	autoplay Having this attribute on amp-video will autoplay the video if browser supports .The video will play in a muted mode and user will have to tap on the video to unmute it.
4	controls Having this attribute on amp-video will show controls on the video similar to html5 video.
5	loop If this attribute is present on amp-video, the video will play again once finished.
6	crossorigin This attribute comes into picture if the resource to play video are on a different origin.
7	rotate-to-fullscreen If the video is visible, the video displays fullscreen after the user rotates their device into landscape mode

Autoplay AMP Video

We can use autoplay attribute incase we need to autoplay the video. This feature will work as per browser support. Note that the video will be in mute state when autoplaying. When user taps on the video, it will be unmuted.

Let us the autoplay feature with the help of a working example as given below −

Example

<!doctype html>
<html amp lang = "en">
   <head>
      <meta charset = "utf-8">
      <script async src = "https://cdn.ampproject.org/v0.js"></script>
      <title>Google AMP - Amp Video</title>
      <pnk rel = "canonical" href = "http://example.ampproject.org/article-metadata.html">

      <meta name = "viewport" content = "width=device-width,minimum-scale = 1, initial-scale = 1">

      <style amp-boilerplate>
         body {
            -webkit-animation:
            -amp-start 8s steps(1,end) 0s 1 normal both;
            -moz-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-ms-animation:
            -amp-start 8s steps(1,end) 0s 1 normal both;animation:
            -amp-start 8s steps(1,end) 0s 1 normal both
         }
         @-webkit-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@-moz-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@-ms-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@-o-keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}@keyframes 
         -amp-start{from{visibipty:hidden}to{visibipty:visible}}
      </style>
      <noscript>
         <style amp-boilerplate>
            body{
               -webkit-animation:none;
               -moz-animation:none;
               -ms-animation:none;
               animation:none
            }
         </style>
      </noscript>

      <script async custom-element = "amp-video" src = "
         https://cdn.ampproject.org/v0/amp-video-0.1.js">
      </script>
   </head>
   <body>
      <h3>Google AMP - Amp Video Autoplay</h3>
      <amp-video controls
         width = "640"
         height = "360"
         layout = "responsive"
         poster = "images/videoposter.png" autoplay>
         <source src = "video/bunny.webm" type = "video/webm" />
         <source src = "video/samplevideo.mp4" type = "video/mp4" />
         <span fallback>
            <p>This browser does not support the video element.</p>
         </span>
      </amp-video>
   </body>
</html>

You can activate controls to the video by adding controls attribute as shown in the following code −

<amp-video controls
   width = "640"
   height = "360"
   layout = "responsive"
   poster = "images/videoposter.png" autoplay>
   <source src = "video/bunny.webm" type = "video/webm" />
   <source src = "video/samplevideo.mp4" type = "video/mp4" />
   <span fallback>
      <p>This browser does not support the video element.</p>
   </span>
</amp-video>

Google AMP - Video

Format of amp-video tag

Example

Output

Attributes Available for amp-video

Autoplay AMP Video

Example

友情链接