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Justin Uberti
Works at Google
Attended University of Virginia
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Justin Uberti

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A first version of the MediaStream Recording API is now available in Chrome 47. This is an early experimental version, but if you're interested in this API you can start playing with it. 

You need: 
- Chrome 47, current dev channel
- Enable experimental Web Platform features under chrome://flags

Demo page:

Current limitations:
- Only supports video, working on adding audio support.
- Only tested on locally sourced MediaStreams
- No internal buffering or configurable Blob interval, encoded data handed back frame by frame
- VP8, hard coded bit rate (VP9 being worked on this quarter)

This is an API with lots of different applications, so we'd love to hear your feedback on what features you think are important to add.
Record Real-Time video and play it back or download as file.
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Loretta Cheeks's profile photo
Justin, I sent you an email at the address on your blog. I look forward to your response.

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Justin Uberti

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Come join Google and Microsoft WebRTCers at the Seattle WebRTC Meetup on April 14!
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Didn't see Microsoft inside the link. Am I missing something?
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A rundown of the many great open source projects that the Chrome team works on (including WebRTC).
Today, I'd like to share with you some remarkable open-source projects the chromium team has been contributing to over the years. This non-exhaustive list is divided into chromium-owned projects and those the team has contributed to.


ANGLE - Almost Native Graphics Layer Engine

Blink - Web rendering engine forked from WebKit

BoringSSL - Crypto and SSL stack derived from OpenSSL

Chrome DevTools - Set of web authoring and debugging tools

Chrome OS BIOS U-Boot replacement - Coreboot payload for booting the system super fast

Chrome OS BIOS Verified Boot

ChromeDriver - WebDriver for Chrome

Chromium Embedded Controller

Chromoting - Remotely control a distant machine

cld2 - Compact Language Detector 2

DOM Distiller - Reader mode on Chrome

GN - Meta-build system that generates NinjaBuild files

google-breakpad - Multi-platform crash reporting system

grit-i18n - Google Resource and Internationalization Tool

GYP - Generate Your Projects

hterm - Cross browser xterm compatible terminal emulator

Native Client - Sandbox for running compiled C and C++ code in the browser

open-vdiff - Open Source VCDIFF delta compression implementation

PDFium - PDF rendering engine

Platform2 - Group of system services that make up the Chromium OS platform

Sanitiser for OpenType - parse and serialize OpenType files

Servo - Debug board used for Chromium OS test and development                                       

Skia - 2D graphic library for drawing text, geometries, and images

Swarming - Distribute tasks fast and efficiently in a heterogeneous fleet of bots

Syzygy - Windows binary transformation/optimization/instrumentation toolchain

Trace-Viewer - Frontend for chrome://tracing and Android systrace

V8 -  JavaScript engine

Web Page Replay - Record live Web pages and use them for local performance testing

WebM - video/audio compression/decompression/container libraries

WebRTC - Web-based real-time communication


Apache Cordova - build native mobile apps using Web technologies
BlueZ - Official Linux Bluetooth protocol stack

Buildbot - Continuous Integration Framework

Clang - C/C++ language family compiler based on LLVM

Coreboot - fast and flexible Open Source firmware

Dart -  Web programming language

Das U-Boot source code - the Universal Boot Loader

FFmpeg - multimedia library

Gentoo Linux

ICU - International Components for Unicode

LLVM - Compiler infrastructure project

LevelDB - key-value storage library

Linux Kernel

Mesa 3D - OpenGL graphics library

modemmanager-next - Broadband modem support daemon

Ninja - Build system with a focus on speed

NSS - Mozilla's Networking and Cryptography library

Selenium - Tool for automated testing of webapps across many browsers
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Justin Uberti

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Lots of nice #webrtc improvements coming in Chrome 42.
Chrome 42 was just cut and is going to beta.

Performance Performance Performance. And lots of bug fixes.!topic/discuss-webrtc/PwuzgUypYos
M42. Summary. Chrome 42 is a performance-focused build. The WebRTC team, along with many other Chrome component teams, have made performance improvements a priority for this release. For example, improved GPU performance significantly on Windows, ...
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Cool #AutoAwesome.
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Reshared because awesome.
Kids, don't try this at home: it's almost certainly not a good idea. But for those of you who are interested in physics, note several important points:

(1) The rocket fires under water: that works because it's a true rocket, carrying both fuel and oxidizer on board and not using air at all. The shape of the nozzle is also important, since water has an amazing ability to absorb heat and thus quench combustion; a caul around the nozzle keeps the water from getting at the ignition point from the sides.

(2) The primary explosion creates a roughly circular set of cracks. Those lead to "big" cracks opening up in the ice, as existing seams and weaknesses get expanded. 

(3) Note that the circular cracks become hexagonal (matching the big cracks) as you move outwards. What's happening is that the inner cracks happen first, and then those start the big cracks, which actually spread faster than the round ones, basically moving at the speed of sound in ice. By the time the last round cracks are forming, they're forming in ice that already has hexagonal cracks in it.

(4) Water is an incompressible fluid, which means that the shock waves are going to hit things under water very, very hard. This is likely to be lethal to anything underwater and nearby, and is how dynamite fishing works. The reasons why that's a terrible idea (and is therefore illegal nearly everywhere) are hopefully obvious.

(5) That said, watching things explode underwater is pretty cool.

h/t +Kee Hinckley 
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Sam Dutton's profile photo
Excellent! I remember something similar on the River Murray in South Australia many years ago. No ice though :).
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Slides from the Introduction to ICE presentation that +Emil Ivov, Brandon Williams, Pal Martinsen, and I gave today.
IETF_ICE_intro (Dallas 92)Introductory Session to IETF ICE/TURN/STUN set of RFCs IETF 92
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+Justin Uberti why isn't allo released here in south Africa yet but it released in other parts the country and in other countries 
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USB-C. 100W power, 10 Gbps bandwidth, 4K resolution, and USB. Finally, one connector to rule them all.
We've been poring over Apple's change to the 8.4mm by 2.6mm USB Type C standard since we got tipped the design of the new MacBook late last year. It is a big change for Apple and puts the future of...
John Kirsopp's profile photoGreg Miernicki's profile photo
20Gbps actually 😉
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Pretty amazing WebRTC demo. Scroll your browser just by moving your hand in the air, courtesy of WebRTC/Web Audio.
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WebRTC release notes for Chrome 41.
Chrome 41 is going to Beta this week. We worked very hard on performance (CPU and RAM) and stability for this one.

Filling issues on with
=> complete details,
=> testing if it exists on canary
=> example repro cases
=> chrome://webrtc-internals and AEC dumps
=> wireshark traces

are the best ways to help us help you make it even faster and better.

Read all about the M41 goodness here:!topic/discuss-webrtc/aGsdjGtjIQA
M41. Main things to pay attention to: Opus FEC is now enabled by default. Several performance improvements in Chrome; much less RAM used per PeerConnection, and video capturing and rendering is more CPU efficient. Improvements to iOS arm64 builds. Features: ...
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The first of what will surely be a long list of WebRTC announcements from network operators. When I talk to operators, it's pretty clear that WebRTC isn't some future consideration - they are all reworking their infrastructure to support WebRTC, and doing it now.
During its annual Developer Summit held the day before CES officially begins, AT&T announced it will be the first carrier in the US to support Web Real-Time Communication, known as WebRTC. The...
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For carriers it's more about building gateway that will connect WebRTC-clients to their IMS infrastructure.
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Trained Professional
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Brief work history: Tech Lead for WebRTC, Google+ Hangouts, Gmail Call Phone, Google Video Chat, AOL Instant Messenger
  • University of Virginia
    Mathematics, 1992 - 1995
Tech Lead, Google Real-time Communications
  • Google
    Tech Lead, 2006 - present
  • AOL
    Chief Architect, 1997 - 2006
  • IFusion Com
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