Engineering and Developers Blog
What's happening with engineering and developers at YouTube
YouTube now defaults to HTML5 <video>
Tuesday, January 27, 2015
Four years ago, we wrote about YouTube’s
early support for the HTML5 <video> tag
and how it performed compared to Flash. At the time, there were limitations that held it back from becoming our preferred platform for video delivery. Most critically, HTML5 lacked support for Adaptive Bitrate (ABR) that lets us show you more videos with less buffering.
Over the last four years, we’ve worked with browser vendors and the broader community to close those gaps, and now, YouTube uses HTML5 <video> by default in Chrome, IE 11, Safari 8 and in beta versions of Firefox.
The benefits of HTML5 extend beyond web browsers, and it's now also used in smart TVs and other streaming devices. Here are a few key technologies that have enabled this critical step forward:
MediaSource Extensions
Adaptive Bitrate (ABR) streaming is critical for providing a quality video experience for viewers - allowing us to quickly and seamlessly adjust resolution and bitrate in the face of changing network conditions. ABR has reduced buffering by more than 50 percent globally and as much as 80 percent on heavily-congested networks. MediaSource Extensions also enable live streaming in game consoles like Xbox and PS4, on devices like Chromecast and in web browsers.
VP9 video codec
HTML5 lets you take advantage of the open VP9 codec, which gives you higher quality video resolution with an average bandwidth reduction of 35 percent. These smaller files allow more people to access 4K and HD at 60FPS -- and videos start 15-80 percent faster. We've already served hundreds of billions of VP9 videos, and you can look for more about VP9 in a future post.
Encrypted Media Extensions
and Common Encryption
In the past, the choice of delivery platform (Flash, Silverlight, etc) and content protection technology (Access, PlayReady) were tightly linked, as content protection was deeply integrated into the delivery platform and even the file format. Encrypted Media Extensions separate the work of content protection from delivery, enabling content providers like YouTube to use a single HTML5 video player across a wide range of platforms. Combined with Common Encryption, we can support multiple content protection technologies on different platforms with a single set of assets, making YouTube play faster and smoother.
WebRTC
YouTube enables everyone to share their videos with the world, whether uploading pre-recorded videos or
broadcasting live
. WebRTC allows us to build on the same technology that enables
plugin-free Google Hangouts
to provide broadcasting tools from within the browser.
Fullscreen
Using the new fullscreen APIs in HTML5, YouTube is able to provide an immersive fullscreen viewing experience (perfect for those
4K videos
), all with standard HTML UI.
Moving to <iframe> embeds
Given the progress we've made with HTML5 <video>, we’re now defaulting to the HTML5 player on the web. We're also deprecating the "old style" of Flash <object> embeds and our Flash API. We encourage all embedders to use the
<iframe> API
, which can intelligently use whichever technology the client supports.
These advancements have benefitted not just YouTube’s community, but the entire industry. Other content providers like Netflix and Vimeo, as well as companies like Microsoft and Apple have embraced HTML5 and been key contributors to its success. By providing an open standard platform, HTML5 has also enabled new classes of devices like Chromebooks and Chromecast. You can support HTML5 by using the
<iframe> API
everywhere you embed YouTube videos on the web.
Richard Leider, Engineering Manager, recently watched,
“Ex Hex - Waterfall.”
Behind the Tube
Monday, January 26, 2015
A billion people watch zillions of hours of YouTube video on devices all over the world. Underneath the hood, the magic that makes YouTube isn’t really magic at all—it’s serious engineering at unparalleled scale.
To bring you closer to the people and projects that make YouTube tick, we’re launching the YouTube Engineering and Developers Blog. About once a month, expect to see behind-the-scenes explanations, tools and tips for developers, and explanations of the most fundamental and interesting technical challenges at YouTube.
We look forward to hearing what you think about these topics, so please let us know in the comments or with a video!
Posted by the YouTube team
Labels
.net
360
acceleration
access control
accessibility
actionscript
activities
activity
android
announcements
apis
app engine
appengine
apps script
as2
as3
atom
authentication
authorization
authsub
best practices
blackops
blur faces
bootcamp
captions
categories
channels
charts
chrome
chromeless
client library
clientlibraries
clientlogin
code
color
comments
compositing
create
curation
custom player
decommission
default
deprecation
devs
direct
discovery
docs
Documentation RSS
dotnet
education
embed
embedding
events
extension
feeds
flash
format
friendactivity
friends
fun
gears
google developers live
google group
googlegamedev
googleio
html5
https
iframe
insight
io12
io2011
ios
iphone
irc
issue tracker
java
javascript
json
json-c
jsonc
knight
legacy
Live Streaming API
LiveBroadcasts API
logo
machine learning
mashups
media:keywords keywords tags metadata
metadata
mobile
mozilla
NAB 2016
news
oauth
oauth2
office hours
open source
partial
partial response
partial update
partners
patch
php
player
playlists
policy
previews
pubsubhubbub
push
python
quota
rails
releases
rendering
reports
responses
resumable
ruby
samples
sandbox
shortform
ssl https certificate staging stage
stack overflow
stage video
staging
standard feeds
storify
storyful
subscription
sup
Super Chat API
survey
tdd
theme
tos
tutorials
updates
uploads
v2
v3
video
video files
video transcoding
virtual reality
voting
VR
watch history
watchlater
webvtt
youtube
youtube api
YouTube Data API
youtube developers live
youtube direct
YouTube live
YouTube Reporting API
ytd
Archive
2017
Nov
Sep
Aug
Mar
Jan
2016
Nov
Oct
Aug
May
Apr
2015
Dec
Nov
Oct
May
Apr
Mar
Jan
2014
Oct
Sep
Aug
May
Mar
2013
Dec
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
2012
Dec
Nov
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2011
Dec
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2010
Dec
Nov
Oct
Sep
Jul
Jun
May
Apr
Mar
Feb
Jan
2009
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
Jan
2008
Dec
Nov
Oct
Sep
Aug
Jul
Jun
May
Apr
Mar
Feb
2007
Dec
Nov
Aug
Jun
May
Feed
YouTube
on
Follow @youtubedev
