Display a video from a Blob Javascript

<video autoplay controls poster="../images/poster.jpg" preload="metadata">Your browser does not support the video element</video>
<script src="js/main.js"></script>

js/main.js:

'use strict';

/* globals FileError */

// get video file via XHR
// store with File API
// read Blob from File API and set as video src using createObjectUrl()
// play video

var video = document.querySelector('video');

function getVideo(fileEntry) {
  get('../video/chrome.webm', function(uInt8Array) {
    var blob = new Blob([uInt8Array], {
      type: 'video/webm'
    });
    writeToFile(fileEntry, blob);
  });
}

function get(url, callback) {
  var xhr = new XMLHttpRequest();
  xhr.open('GET', url, true);
  xhr.responseType = 'arraybuffer';
  xhr.send();

  xhr.onload = function() {
    if (xhr.status !== 200) {
      alert('Unexpected status code ' + xhr.status + ' for ' + url);
      return false;
    }
    callback(new Uint8Array(xhr.response));
  };
}

// code adapted from HTML5 Rocks article by Eric Bidelman
// http://www.html5rocks.com/en/tutorials/file/filesystem/

// init a FileSystem
// create a file
// write to the file
// read from the file

window.requestFileSystem =
window.requestFileSystem || window.webkitRequestFileSystem;

window.requestFileSystem(window.TEMPORARY, 5 * 1024 * 1024, // 5MB
  handleInitSuccess, handleError);

function handleInitSuccess(fileSystem) {
  window.fileSystem = fileSystem;
  log('Initiated FileSystem: ' + fileSystem.name);
  createFile('video.webm');
}

function createFile(fullPath) {
  window.fileSystem.root.getFile(fullPath, {
    create: true
    /* exclusive: true */
  },
  function(fileEntry) {
    log('Created file: ' + fileEntry.fullPath);
    getVideo(fileEntry);
  }, handleError);
}

function writeToFile(fileEntry, blob) {
  // Create a FileWriter object for fileEntry
  fileEntry.createWriter(function(fileWriter) {
    fileWriter.onwriteend = function() {
      // read from file
      log('Wrote to file ' + fileEntry.fullPath);
      readFromFile(fileEntry.fullPath);
    };
    fileWriter.onerror = function(e) {
      log('Write failed: ' + e.toString());
    };
    // Create a new Blob and write it to file
    fileWriter.write(blob);
  }, handleError);
}

function readFromFile(fullPath) {
  window.fileSystem.root.getFile(fullPath, {}, function(fileEntry) {
    // Get a File object representing the file
    // then use FileReader to read its contents
    fileEntry.file(function(file) {
      var reader = new FileReader();
      reader.onloadend = function() {
        // video.src = this.result;
        video.src = URL.createObjectURL(new Blob([this.result]));
      };
      // reader.readAsDataURL(file);
      reader.readAsArrayBuffer(file);
    }, handleError);
  }, handleError);
}

function handleError(e) {
  switch (e.code) {
  case FileError.QUOTA_EXCEEDED_ERR:
    log('QUOTA_EXCEEDED_ERR');
    break;
  case FileError.NOT_FOUND_ERR:
    log('NOT_FOUND_ERR');
    break;
  case FileError.SECURITY_ERR:
    log('SECURITY_ERR');
    break;
  case FileError.INVALID_MODIFICATION_ERR:
    log('INVALID_MODIFICATION_ERR');
    break;
  case FileError.INVALID_STATE_ERR:
    log('INVALID_STATE_ERR');
    break;
  default:
    log('Unknown error');
    break;
  }
}

var data = document.getElementById('data');

function log(text) {
  data.innerHTML += text + '<br />';
}

document.querySelector('video').addEventListener('loadedmetadata', function() {
  var fileName = this.currentSrc.replace(/^.*[\\\/]/, '');
  document.querySelector('#videoSrc').innerHTML = 'currentSrc: ' + fileName +
  '<br /> videoWidth: ' + this.videoWidth + 'px<br /> videoHeight: ' + this
  .videoHeight + 'px';
});

Reference:

http://stackoverflow.com/questions/14317179/display-a-video-from-a-blob-javascript

http://simpl.info/video/offline/

https://github.com/samdutton/simpl/blob/gh-pages/video/offline/index.html