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[THEME MUSIC]

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>> DAVID J. MALAN: Can you hear me, world?

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So in next week's episode we'll
talk about microphone technology.

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But for now, let's begin.

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Hello, world, we are
back, as is my voice.

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And this is CS50 Live.

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>> And boy, do we have a good
show for you this week.

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In particular, we've
got the Heartbleed bug

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that's been all over the news of
late, some stories from students,

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a trip to Vegas, a behind
the scenes tour of Dropbox.

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And I'm hearing, yes, CS50's
own Ramon Galvin is back.

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CS50's Ramon Galvin is in
the studio again today.

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>> But first, some desk lamps.

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Of course desk lamps have been a bit
of a thing this semester in CS50.

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And you may recall Ahmad,
from a previous episode, who

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submitted a video
making his case for why

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he'd like to receive
his own CS50 desk lamp.

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Well, we sent a desk
lamp ultimately to Ahmad.

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And he kindly sent us
this photo of himself

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in Pakistan with a CS50 desk lamp.

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>> Meanwhile, you may recall Lamp
Story, submitted by Eggers in Latvia.

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We sent over a desk
lamp to Latvia as well.

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And pictured here is that desk lamp.

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Finally, you may recall Philip
who didn't just submit a photo,

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but also submitted a video
via which to thank us

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for his desk lamp, which we
sent all the way to Germany.

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Let's take a look.

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>> PHILLIP: Hi.

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Dear David, and dear all of
you amazing people at CS50.

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I'm Phil and I want to thank you
so much for this incredible gift.

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It is unbelievable to
me that you actually

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sent this all the way
over here to Germany.

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But you know what?

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Why don't I thank you personally?

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>> Hey, David, I want to thank you
so much for this CS50 desk lamp.

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You can not imagine
what this means to me.

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>> DAVID J. MALAN: Desk lamp?

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>> PHILLIP: Right.

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OK, I'm going to leave,
but, yeah, thanks.

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DAVID J. MALAN: Now, two of your
classmates actually traveled

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to us to have a chat of late.

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In particular, Amy from Massachusetts
and Jack from Dublin, Ireland,

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came all the way to Sanders Theater
to sit down and talk about CS50

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past and present.

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>> This is Sanders Theater.

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So this is where CS50's
lectures are held.

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Thanks so much for coming to campus.

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Shall we start with the introductions?

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I'm David.

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>> AMY: I'm Amy.

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I work on the web and I
live here in Cambridge.

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>> JACK: I'm Jack and I'm
from Dublin, Ireland.

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I'm a junior in high school.

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>> DAVID J. MALAN: And what brings you here
today in particular from so far away?

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JACK: For a visit to Boston.

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>> AMY: How has CS50 evolved
as you've been teaching it?

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>> DAVID J. MALAN: It's definitely
gotten more dramatic over the years.

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We've been filming since 2007, so
we can literally go back in time

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and watch past years, first
lectures in particular.

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And I think the first lecture
in 2007 was pretty much

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me, coming out in front of the class.

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Saying, hello, this is CS50.

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And we dove into the day's material.

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>> All right, so welcome
to Computer Science 50,

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Introduction to Computer Science 1.

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My name is David Malin and I
will be your instructor this--

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>> Now there's music.

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The lights go down.

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We drop down a huge screen.

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There may or may not be
Muppets in a given year.

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And it's funny, because this
has all happened very gradually

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over the years, just a
little bit more each year.

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But the delta, now, between the
first year and the last year

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is actually rather atrocious, just how
different the first five minutes are.

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>> AMY: I'm curious, what do you see
as the differences between the edX

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version and the live course?

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>> DAVID J. MALAN: So curricularly
and technologically CS50

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on campus and CS50x off campus
are fundamentally the same.

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What does differ between the
two is the level of support

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that we're able to provide.

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Even though CS50 has a huge team of
some 100 teaching fellows, course

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assistants, myself, and
our production team--

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we can just barely keep up
with the 700 students on campus

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and the 150 Extension School students
who are local or online themselves.

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So for CS50x, we simply don't have
the support structure of office hours,

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for instance, four nights
a week for several hours.

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JACK: And what do you guys talk about in
office hours that will be different to,

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say, what you have on lectures,
or on sections, or shorts?

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DAVID J. MALAN: On campus
office hours are really

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opportunities for students to
pose questions, one on one,

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with a member of the teaching staff
or even a classmate of theirs nearby.

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And generally wrestle with bugs
that they're having in their codes.

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>> AMY: I think Reddit kind of gives
a reasonable facsimile of an office

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hours.

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>> DAVID J. MALAN: Agreed, agreed.

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I've been really impressed,
though, with the Reddit community

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and the newcomers to
the group, too-- just

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how eager and hopeful people have been.

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And Reddit definitely lends itself
better, I think, to posting of code

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and having threaded discussions.

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>> JACK: And do you think
people should try,

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if they know they're
doing something wrong

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or it's like, they've implemented--
spent too much time on it,

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think they should stop and start again?

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Or look for help?

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Or how should they--

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>> DAVID J. MALAN: Take a break, minimally.

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Sometimes, especially for me at least,
as your stress level starts to rise you

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start hacking away and copying
and pasting, forgetting

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what you've already tried.

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It's just time to go to
sleep, or go take a jog,

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or go shower, and just
kind of get some distance.

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And this has happened
many, many times to me

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where I'll be lying there in bed
even, or even driving to work,

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or walking somewhere, kind
of debugging in my head.

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>> And only once you have that distance
and a lot less stress on your shoulders,

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I think, can you realize,
like, oh, I'm an idiot.

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I forgot to call this function,
or initialize some variable.

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>> So as a little surprise if you'd like
to take a look under your CS50 seat

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cushion, a little something awaits you.

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Those were good looks.

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Did we get those looks?

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>> Under their seat cushions, of
course, was a bit more Dropbox space.

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Now you may recall we recently
traveled to Saint Louis, Missouri,

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where we had a unique opportunity
to actually blow glass

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at the Third Degree Glass factory.

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Our host for the day made
this beautiful bowl of glass

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by spinning and spinning it until
you got this beautiful wavy effect.

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And this now lives in our
offices here in Cambridge.

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>> I, on the other hand, made
this big ball of orange glass

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that now sits on my desk.

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But we were in Saint Louis, of
course, for the CS50 hackathon

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in Saint Louis with Launchcode,
where we had an opportunity

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to sit down with a number of your
classmates and hear their CS50 stories.

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>> EZRA: Once I saw computer
coding and the kind of-- that's

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the career that I want to be in.

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And I think that I would
be very good at it.

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>> CHARLES: Well, I've been
job hunting for a while.

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Bachelor of Science,
biomedical engineering.

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It hasn't been going too well.

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So I thought maybe I'd look
into a different field.

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>> KIMBERLY: In Green Bay, Wisconsin
I was a school counselor.

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And I really knew I
wanted to change careers.

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>> SAM: I've heard a lot of
people saying, like, everyone

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should learn how to code.

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Everyone should be exposed to it.

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And before I was just kind
of like, eh, whatever.

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>> AUSTIN: I had taken a semester off.

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And I'm now doing the CS50x program.

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>> KELLI: It's very accessible
to anyone at all.

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>> LEANNE: I've been a
developer in the past.

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But I had a situation and I wanted
to kind of increase my confidence,

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and I wanted to learn
C, and I wanted to learn

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PHP, which I saw that CS50 was teaching.

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AUSTIN: People are really helpful.

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There's definitely more
of a community than you

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would think from an online course.

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>> KELLI: I'm working on my problem
set five, that I just started.

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So I get to do a little forensics.

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>> CHARLES: It has been challenging.

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It's definitely meant
to stretch your limits.

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I'm working on problem set five.

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>> KIMBERLY: My classmate and I are
working on our final project.

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>> SAM: I'm working on my final project.

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I've got two other people working
with me, we're the tri-force of power.

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>> LEANNE: I'm attempting to work on
an iOS app that is a calendar agenda

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application that I wanted to create,
just for my own use, to start out with.

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>> AUSTIN: My final project is
going to be a website that

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is an image and visual repository.

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Basically it's going to have
a listing of helpful phrases

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and sign language for medical personnel.

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>> EZRA: Let's say my final project
was a puppet doing a dance,

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and they asked me, can you make this
puppet to do this dance twice as fast?

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I would be able to go to my code, change
it, save it, compile it, upload it,

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and show them right away that
I can-- that not only did I

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make this final project, I understand.

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I can tweak it however
they want me to tweak it.

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>> CHARLES: I figure once I get
my final project completed

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and some potential
employers have a chance

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to look at that they'll have a
better assessment of whether they

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think I'll be a good fit for them.

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SAM: Now I'm very confident and I'm
learning new stuff all the time.

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And it's great.

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It's changed my life.

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>> EZRA: This is really
hard material, especially

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if you're doing this and also
working, and maybe also have a family,

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and maybe also have children,
and maybe also have a mortgage.

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But it's so worth it if
you just put the effort in.

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What you get out is so much more
valuable than the time that you put in.

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DAVID J. MALAN: And
now, this week in tech.

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Odds are you've heard of
the so-called Heartbleed

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bug, which has affected web
servers throughout the world.

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But what is this bug, exactly?

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Well, turns out that many web
servers run software called open

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SSL, where SSL of course
is Secure Sockets Layer.

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And this is the technology that
encrypts traffic between a web browser,

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or client, and a web server.

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Now unfortunately, in
December of 2011, a programmer

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introduced an accidental bug into
the source code for open SSL.

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>> And open SSL unfortunately is
used in so many other products,

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among them the Apache
web server, and others,

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that are hugely popular on the
internet for hosting websites.

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The result of this was that the
following attack is possible.

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As part of open SSL there's a
so-called heartbeat feature,

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whereby a client like a browser
can send a message or a payload,

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which is really just a string,
like hello, to a server.

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And in addition to that
payload it sends a number

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which should be the
length of that payload.

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In the case of hello, it should be five.

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>> Unfortunately, the bug in
open SSL operated as follows.

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It ignored that number.

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And so if you-- rather,
it trusted that number.

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So if you, the client, sent a message
like hello, and not the number 5

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but the number 100, what would happen
is that the server would blindly

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respond to that payload by
echoing back not only hello,

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those 5 bytes, but 95 additional
bytes thereby trusting

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that you were telling the truth when you
said that the payload was in fact 100

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bytes.

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Now why is that problematic?

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>> Well, you may recall
from CS50, of course,

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from memory management that
on the stack and the heap

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are remnants of data paths, when you've
called a function, used a variable,

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those values stay in memory even
if you're no longer actively using

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those chunks of memory.

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So when the server responds not with 5
bites but with 100 bytes, 95 of which

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are not technically supposed
to go back to the client,

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those 95 bytes could contain
passwords, or the server's

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security certificates, or the servers
secret keys, so to speak, all of which

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are used for encryption.

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00:11:46,610 --> 00:11:49,380
>> And so ultimately your
information could be handed back

236
00:11:49,380 --> 00:11:52,157
to some random adversary
on the internet simply

237
00:11:52,157 --> 00:11:54,240
because your password, or
credit card information,

238
00:11:54,240 --> 00:11:56,120
or something else that's
sensitive happened

239
00:11:56,120 --> 00:11:59,620
to be in the web server's memory
at that particular location.

240
00:11:59,620 --> 00:12:01,630
Now this was a big
deal, because this bug

241
00:12:01,630 --> 00:12:03,690
affected web servers
throughout the world.

242
00:12:03,690 --> 00:12:08,480
Among them Amazon Web Services, Box,
Dropbox, Etsy, Flickr, GitHub, Gmail,

243
00:12:08,480 --> 00:12:11,950
Go Daddy, Google, Instagram,
Minecraft, Netflix, OKCupid, Pinterest,

244
00:12:11,950 --> 00:12:15,760
SoundCloud, Tumblr, Twitter,
Venmo, Wikipedia, WordPress, Yahoo,

245
00:12:15,760 --> 00:12:19,030
YouTube-- and those are just
the companies, just some

246
00:12:19,030 --> 00:12:22,720
of the companies that actually disclosed
that their servers had been running

247
00:12:22,720 --> 00:12:26,560
the afflicted software and had
only recently, as this past week,

248
00:12:26,560 --> 00:12:27,790
been updated.

249
00:12:27,790 --> 00:12:31,450
>> Now it turns out the fix, in source code
for, this Heartbleed bug is actually

250
00:12:31,450 --> 00:12:32,530
remarkably simple.

251
00:12:32,530 --> 00:12:35,710
It pretty much boils down
to these two lines of code.

252
00:12:35,710 --> 00:12:39,030
If payload is greater than
the actual length, return 0.

253
00:12:39,030 --> 00:12:42,680
Do not return some
potentially disclosing bits.

254
00:12:42,680 --> 00:12:45,839
Now in reality the lines of
code were a little more complex.

255
00:12:45,839 --> 00:12:47,130
It looked a bit more like this.

256
00:12:47,130 --> 00:12:48,720
But this is just some
additional arithmetic

257
00:12:48,720 --> 00:12:50,428
and there were a few
other lines of code,

258
00:12:50,428 --> 00:12:52,530
but the fix really was that simple.

259
00:12:52,530 --> 00:12:54,470
>> And so if you've never
believed in lectures

260
00:12:54,470 --> 00:12:57,660
when we say that you should always
check the boundaries of your array

261
00:12:57,660 --> 00:13:00,170
and make sure to check the
lengths of any chunk of memory

262
00:13:00,170 --> 00:13:03,880
before blindly traversing
through your computer's memory,

263
00:13:03,880 --> 00:13:05,320
this is what can happen.

264
00:13:05,320 --> 00:13:08,954
And truly it's been a
globally impactful bug.

265
00:13:08,954 --> 00:13:11,620
Now what can you yourself do to
learn more and protect yourself?

266
00:13:11,620 --> 00:13:14,390
Well, head to heartbleed.com,
which is a terrific website that

267
00:13:14,390 --> 00:13:18,280
explains in a bit more detail exactly
what the threat is, how folks have

268
00:13:18,280 --> 00:13:20,317
responded, what
software's been affected,

269
00:13:20,317 --> 00:13:21,650
and how you can defend yourself.

270
00:13:21,650 --> 00:13:25,210
But it pretty much boils down
to this-- change your passwords,

271
00:13:25,210 --> 00:13:27,585
arguably on most any
website you know if unsure

272
00:13:27,585 --> 00:13:29,460
whether that particular
website was affected.

273
00:13:29,460 --> 00:13:31,560
>> Because one of the scariest
things about this bug

274
00:13:31,560 --> 00:13:33,530
is that it's not so much auditable.

275
00:13:33,530 --> 00:13:36,580
It's not clear if, even
over the past two years,

276
00:13:36,580 --> 00:13:39,890
a server was vulnerable, if your
information was indeed compromised.

277
00:13:39,890 --> 00:13:42,120
So as is the case
generally with security,

278
00:13:42,120 --> 00:13:45,350
the best approach is paranoia
and change any passwords

279
00:13:45,350 --> 00:13:48,320
on websites that are
particularly sensitive to you.

280
00:13:48,320 --> 00:13:50,990
But head to that URL there
for even more detail.

281
00:13:50,990 --> 00:13:53,750
>> Now in other news, Mark
Zuckerberg recently posted this.

282
00:13:53,750 --> 00:13:55,470
I'm excited to announce
that we've agreed

283
00:13:55,470 --> 00:13:59,260
to acquire Oculus VR, the leader
in virtual reality technology.

284
00:13:59,260 --> 00:14:01,640
Now virtual reality is
an interesting thing

285
00:14:01,640 --> 00:14:03,557
that's beginning to gain
a bit more traction.

286
00:14:03,557 --> 00:14:05,640
It generally involves
putting on a pair of goggles

287
00:14:05,640 --> 00:14:08,960
that might look like these inside
of which are a pair of lenses that

288
00:14:08,960 --> 00:14:12,335
allow you to see a computer screen
right up close to your face.

289
00:14:12,335 --> 00:14:15,210
And on that computer screen could
be anything, the inside of a house,

290
00:14:15,210 --> 00:14:18,540
the outside of the house, a
virtual world inside of a game.

291
00:14:18,540 --> 00:14:22,260
And the result is an incredibly
immersive opportunity

292
00:14:22,260 --> 00:14:25,594
to feel as though you're actually
someplace that you're actually not.

293
00:14:25,594 --> 00:14:27,510
I, for instance, might
be in a conference room

294
00:14:27,510 --> 00:14:31,230
when really I think I'm in
a Tron-like virtual world.

295
00:14:31,230 --> 00:14:32,790
And indeed, I had an opportunity.

296
00:14:32,790 --> 00:14:35,623
I haven't personally played with
Oculus, but I did visit our friends

297
00:14:35,623 --> 00:14:38,270
in Seattle, Washington,
recently at Valve software, who

298
00:14:38,270 --> 00:14:40,860
were working on a very
similar VR technology.

299
00:14:40,860 --> 00:14:43,140
And I was very fortunate
to have the opportunity

300
00:14:43,140 --> 00:14:47,630
to put on their pair of
goggles for 60 seconds of this.

301
00:14:47,630 --> 00:15:48,240
>> [MUSIC PLAYING]

302
00:15:48,240 --> 00:15:51,190
>> Now, CS50's own Dan Coffey
also had an opportunity

303
00:15:51,190 --> 00:15:53,590
to take a trip recently to
Mountain View, California,

304
00:15:53,590 --> 00:15:56,360
where he sat down with our
friends at Dropbox, among them

305
00:15:56,360 --> 00:15:59,710
CS50's own former head teaching
fellow Thomas Carriero,

306
00:15:59,710 --> 00:16:02,140
who's been responsible for
all of that Dropbox space

307
00:16:02,140 --> 00:16:03,740
underneath your seat cushions.

308
00:16:03,740 --> 00:16:07,100
Thomas very kindly opened the doors
of Dropbox and gave us an exclusive

309
00:16:07,100 --> 00:16:10,600
behind the scenes of what
it's like to work at Dropbox

310
00:16:10,600 --> 00:16:14,685
and daresay live at Dropbox.

311
00:16:14,685 --> 00:16:19,040
>> THOMAS CARRIERO: Hi, I'm Thomas
Carriero, former CS50 head TF.

312
00:16:19,040 --> 00:16:21,980
We're here at the Dropbox headquarters
in San Francisco, California.

313
00:16:21,980 --> 00:16:22,490
Welcome.

314
00:16:22,490 --> 00:16:23,490
I'm going to show you on a tour.

315
00:16:23,490 --> 00:16:24,031
Come with me.

316
00:16:24,031 --> 00:16:26,700

317
00:16:26,700 --> 00:16:27,200
Cool.

318
00:16:27,200 --> 00:16:30,030
So this balloon right here,
this green check mark,

319
00:16:30,030 --> 00:16:34,020
is the balloon that we put on your
desk when you first join the company.

320
00:16:34,020 --> 00:16:37,900
And the idea is that the balloon
will stay kind of up there as long

321
00:16:37,900 --> 00:16:38,790
as you're a new hire.

322
00:16:38,790 --> 00:16:42,618
So the balloon of course loses
helium over time and by the time

323
00:16:42,618 --> 00:16:47,420
the balloon is dead
you're no longer a noob.

324
00:16:47,420 --> 00:16:51,460
This takes a couple of months to
happen because these are really, really

325
00:16:51,460 --> 00:16:52,560
expensive balloons.

326
00:16:52,560 --> 00:16:57,800
We think we might keep the green check
mark balloon business in business.

327
00:16:57,800 --> 00:17:00,230
>> Cool, so this right here is AT&T Park.

328
00:17:00,230 --> 00:17:02,530
This is where the San
Francisco Giants play.

329
00:17:02,530 --> 00:17:08,190
We actually have a Dropbox box suite,
one of our other awesome amenities,

330
00:17:08,190 --> 00:17:09,170
just across the way.

331
00:17:09,170 --> 00:17:11,479
So I'm standing by this
really cool light display.

332
00:17:11,479 --> 00:17:13,770
So what's going on here is
we're getting real time data

333
00:17:13,770 --> 00:17:16,950
about what's happening
in our Mailbox app.

334
00:17:16,950 --> 00:17:19,960
Each of the colors corresponds
to a different action.

335
00:17:19,960 --> 00:17:23,060
>> And so as users are doing
these actions, these lights

336
00:17:23,060 --> 00:17:26,619
are lighting up with those colors to
kind of let us know what's going on.

337
00:17:26,619 --> 00:17:30,960
Sometimes if stuff is going wrong, the
colors will all start to be one color

338
00:17:30,960 --> 00:17:33,219
and we know that something
bad is happening.

339
00:17:33,219 --> 00:17:34,968
So this is kind of one
of the ways that we

340
00:17:34,968 --> 00:17:36,676
keep track of what's
going on in Mailbox.

341
00:17:36,676 --> 00:17:39,500

342
00:17:39,500 --> 00:17:42,250
>> Cool, so let's see what's
for dinner tonight.

343
00:17:42,250 --> 00:17:46,750
Looks like we have eight hour
smoked beef brisket right here.

344
00:17:46,750 --> 00:17:49,310
And right here is my favorite
station, the Indian station.

345
00:17:49,310 --> 00:17:53,500
It's an open face samosa chop today.

346
00:17:53,500 --> 00:17:55,290
Well, I guess that was
my favorite station

347
00:17:55,290 --> 00:17:57,150
but this is my other favorite station.

348
00:17:57,150 --> 00:17:58,440
>> This is the pizza station.

349
00:17:58,440 --> 00:18:02,180
So they always make different kinds of
pizza with our pizza oven right there.

350
00:18:02,180 --> 00:18:06,330
Looks like they're making a Sicilian
pizza, which is one of my favorites.

351
00:18:06,330 --> 00:18:10,210
All right, so the chef told me
that they are freshly made Ho Hos.

352
00:18:10,210 --> 00:18:13,100
I told him I was going to wait
until after I'd eaten my dinner

353
00:18:13,100 --> 00:18:15,350
but I'm definitely going to
have one of those tonight.

354
00:18:15,350 --> 00:18:19,323
OK, I'm going to have mine now.

355
00:18:19,323 --> 00:18:19,823
Real good.

356
00:18:19,823 --> 00:18:23,290

357
00:18:23,290 --> 00:18:26,690
>> So this is kind of the bonus station
that's outside of the tech shop.

358
00:18:26,690 --> 00:18:29,850
For lunch we have Mexican
food here and sushi here.

359
00:18:29,850 --> 00:18:34,050
And for dinner we have
some kind meat delicious.

360
00:18:34,050 --> 00:18:37,340
Looks like roasted pork loin tonight.

361
00:18:37,340 --> 00:18:40,785
Get a close up on that.

362
00:18:40,785 --> 00:18:42,160
Cool, so this is our design area.

363
00:18:42,160 --> 00:18:44,810
This is where we design
a bunch of the products.

364
00:18:44,810 --> 00:18:47,480
We have lots of fun
poster boards and stuff,

365
00:18:47,480 --> 00:18:50,320
with kind of all the mocks
that we're working on.

366
00:18:50,320 --> 00:18:53,380
We also have along the
ground a bunch of the mocks

367
00:18:53,380 --> 00:18:56,130
that we've been working
on over the years.

368
00:18:56,130 --> 00:18:58,490
So you can get a close
up of that in a second.

369
00:18:58,490 --> 00:19:01,550
>> But this sign is one of my
favorite things about Dropbox.

370
00:19:01,550 --> 00:19:03,650
So this sign actually
came from the old office.

371
00:19:03,650 --> 00:19:05,520
And our slogan is, it just works.

372
00:19:05,520 --> 00:19:10,310
But if you look closely, there's
a subliminal message in the sign.

373
00:19:10,310 --> 00:19:14,630
>> So one of my favorite parts about
Dropbox are these vending machines.

374
00:19:14,630 --> 00:19:17,630
Instead of having chips or
soda or anything like that,

375
00:19:17,630 --> 00:19:19,270
we actually have electronics.

376
00:19:19,270 --> 00:19:24,360
So if you need a new trackpad, or
a new keyboard, or some headphones,

377
00:19:24,360 --> 00:19:27,160
all you need to do is swipe
your badge right here.

378
00:19:27,160 --> 00:19:30,140
Type in the number and then
the out comes your electronics.

379
00:19:30,140 --> 00:19:30,780
Pretty awesome.

380
00:19:30,780 --> 00:19:33,029
Thanks so much for joining
me on this tour of Dropbox.

381
00:19:33,029 --> 00:19:35,230
It's been really fun showing you around.

382
00:19:35,230 --> 00:19:37,800
>> I'm going to close this out
with the way we close out

383
00:19:37,800 --> 00:19:40,000
all of our all hands meetings.

384
00:19:40,000 --> 00:19:41,690
This is a special chant we do.

385
00:19:41,690 --> 00:19:44,050
Can I get some help here?

386
00:19:44,050 --> 00:19:47,800
One, two, three-- Dropbox!

387
00:19:47,800 --> 00:19:49,370
It's usually much cooler than that.

388
00:19:49,370 --> 00:19:57,986

389
00:19:57,986 --> 00:20:00,110
DAVID J. MALAN: Now if
you'd like to visit Dropbox,

390
00:20:00,110 --> 00:20:04,570
head to Mountain View, California, hop
on Route 101 north to San Francisco,

391
00:20:04,570 --> 00:20:06,110
where they actually are.

392
00:20:06,110 --> 00:20:07,930
Now we've also had an
opportunity recently

393
00:20:07,930 --> 00:20:11,160
to travel to Las Vegas,
Nevada for the NAB show,

394
00:20:11,160 --> 00:20:13,390
the National Association
for Broadcasters show,

395
00:20:13,390 --> 00:20:16,160
which brings together some
100,000 people interested

396
00:20:16,160 --> 00:20:18,770
in audio and video and
technology more generally

397
00:20:18,770 --> 00:20:21,160
to talk about the very
latest and greatest.

398
00:20:21,160 --> 00:20:24,175
>> CS50's own Ramon Galvin took
this trip and brought with him

399
00:20:24,175 --> 00:20:28,816
a camera crew in order to this
footage from the show's floor.

400
00:20:28,816 --> 00:20:29,941
RAMON GALVIN: Hello, world.

401
00:20:29,941 --> 00:20:31,785
OK, I got it.

402
00:20:31,785 --> 00:20:32,710
Hello, world.

403
00:20:32,710 --> 00:20:34,634
Do I have to say my name?

404
00:20:34,634 --> 00:20:37,474
>> CAMERAMAN: Correspondent in the field .

405
00:20:37,474 --> 00:20:39,390
RAMON GALVIN: Can I get
a lower third of that?

406
00:20:39,390 --> 00:20:43,329
Correspondent in field.

407
00:20:43,329 --> 00:20:44,689
>> CAMERAMAN: Senior.

408
00:20:44,689 --> 00:20:45,814
RAMON GALVIN: There you go.

409
00:20:45,814 --> 00:20:53,280

410
00:20:53,280 --> 00:20:55,632
I know, but I have to
do it. [INAUDIBLE].

411
00:20:55,632 --> 00:21:08,082

412
00:21:08,082 --> 00:21:09,078
I'm clueless.

413
00:21:09,078 --> 00:21:14,580

414
00:21:14,580 --> 00:21:16,474
>> Now's my prima donna pose.

415
00:21:16,474 --> 00:21:35,397

416
00:21:35,397 --> 00:21:37,230
DAVID J. MALAN: And
they keep mentioning 4K.

417
00:21:37,230 --> 00:21:40,080
What is 4K exactly?

418
00:21:40,080 --> 00:21:42,884
>> RAMON GALVIN: That's a
really good question.

419
00:21:42,884 --> 00:21:43,550
Very basically--

420
00:21:43,550 --> 00:21:46,017
>> DAVID J. MALAN: Cut to
a clip explaining 4K.

421
00:21:46,017 --> 00:21:53,472

422
00:21:53,472 --> 00:21:54,410
Hello, world.

423
00:21:54,410 --> 00:21:55,749
My name is David Malan.

424
00:21:55,749 --> 00:21:57,040
RAMON GALVIN: I'm Ramon Galvin.

425
00:21:57,040 --> 00:21:59,225
DAVID J. MALAN: And we're here
at NAP, the National Association

426
00:21:59,225 --> 00:22:01,620
of Broadcasters conference
in Las Vegas, Nevada.

427
00:22:01,620 --> 00:22:02,680
But why are we here?

428
00:22:02,680 --> 00:22:03,804
RAMON GALVIN: I don't know.

429
00:22:03,804 --> 00:22:05,270
I don't know, David.

430
00:22:05,270 --> 00:22:07,040
>> DAVID J. MALAN: That was pretty good.

431
00:22:07,040 --> 00:22:08,270
Is this usable?

432
00:22:08,270 --> 00:22:10,572
>> RAMON GALVIN: Probably not.

433
00:22:10,572 --> 00:22:12,655
DAVID J. MALAN: We're back,
as is CS50's own Ramon

434
00:22:12,655 --> 00:22:16,010
Galvin, who you may recall
from last week's episode.

435
00:22:16,010 --> 00:22:17,820
Ramon, so glad you are indeed back.

436
00:22:17,820 --> 00:22:19,230
>> RAMON GALVIN: I'm glad I
still have a job, David.

437
00:22:19,230 --> 00:22:21,105
>> DAVID J. MALAN: So let's
address the elephant

438
00:22:21,105 --> 00:22:22,980
that was in the room in
Las Vegas, namely 4K.

439
00:22:22,980 --> 00:22:25,820
I've heard about this in the context
of TVs and computer monitors,

440
00:22:25,820 --> 00:22:27,490
but what is 4K?

441
00:22:27,490 --> 00:22:28,970
>> RAMON GALVIN: So it's a resolution.

442
00:22:28,970 --> 00:22:31,570
Whenever you're watching a
walk through video or a lecture

443
00:22:31,570 --> 00:22:33,670
you get what we call 1080p video.

444
00:22:33,670 --> 00:22:37,605
What that means that the
video is 1,000 pixels tall.

445
00:22:37,605 --> 00:22:38,680
>> DAVID J. MALAN: Or 1080.

446
00:22:38,680 --> 00:22:39,596
>> RAMON GALVIN: Or 1080.

447
00:22:39,596 --> 00:22:42,620
Or roughly 2,000 pixels wide.

448
00:22:42,620 --> 00:22:49,329
Now 4K is 4,000 pixels wide, roughly,
and roughly 2,000 pixels tall.

449
00:22:49,329 --> 00:22:50,120
DAVID J. MALAN: OK.

450
00:22:50,120 --> 00:22:53,950
So that's kind of like having
a grid of four 1080p monitors

451
00:22:53,950 --> 00:22:55,040
right in front of you.

452
00:22:55,040 --> 00:22:55,956
>> RAMON GALVIN: Exactly.

453
00:22:55,956 --> 00:22:59,310
DAVID J. MALAN: OK, so that's all
fine and good but why is this useful?

454
00:22:59,310 --> 00:23:01,325
>> RAMON GALVIN: I'm glad I asked you
to ask me that question, David.

455
00:23:01,325 --> 00:23:03,080
>> DAVID J. MALAN: It's
on the teleprompter.

456
00:23:03,080 --> 00:23:04,996
>> RAMON GALVIN: So there's
a documentarian named

457
00:23:04,996 --> 00:23:08,180
Errol Morris that actually
makes use of 4K technology.

458
00:23:08,180 --> 00:23:10,820
Ordinarily to shoot an
interview, which he usually does,

459
00:23:10,820 --> 00:23:14,100
he would have to either use multiple
cameras to get a zoomed in shot

460
00:23:14,100 --> 00:23:17,290
or a zoomed out shot, or
shoot the interview twice

461
00:23:17,290 --> 00:23:19,850
to get the same zoomed
in, zoomed out shot.

462
00:23:19,850 --> 00:23:25,890
However, now he's using a 4K
camera to shoot one huge 4K shot.

463
00:23:25,890 --> 00:23:30,157
And then when he's editing,
artificially cropping that shot.

464
00:23:30,157 --> 00:23:31,990
DAVID J. MALAN: And
zooming in, essentially,

465
00:23:31,990 --> 00:23:35,600
to give you still 1080p but only
some of the pixels from the 4K image.

466
00:23:35,600 --> 00:23:38,720
>> RAMON GALVIN: Exactly, giving
him multiple camera shots

467
00:23:38,720 --> 00:23:40,262
out of that one original camera shot.

468
00:23:40,262 --> 00:23:41,428
DAVID J. MALAN: Interesting.

469
00:23:41,428 --> 00:23:43,370
So how could we make
use of this for CS50?

470
00:23:43,370 --> 00:23:46,160
>> RAMON GALVIN: I'm glad you asked
me that question, too, David.

471
00:23:46,160 --> 00:23:50,500
Because I shot the walk through
videos with Zamyla last semester.

472
00:23:50,500 --> 00:23:53,015
And for those videos we would
have to run through the walk

473
00:23:53,015 --> 00:23:55,240
through once with a zoomed out shot.

474
00:23:55,240 --> 00:23:59,390
And then I'd have to adjust the
camera to get a zoomed in shot.

475
00:23:59,390 --> 00:24:03,130
And then we'd run through it again,
running through it two times.

476
00:24:03,130 --> 00:24:05,484
With a 4K camera we can cut
our production time in half.

477
00:24:05,484 --> 00:24:06,400
DAVID J. MALAN: I see.

478
00:24:06,400 --> 00:24:09,244
So that should be quite exciting
for us, then, this fall.

479
00:24:09,244 --> 00:24:10,160
RAMON GALVIN: Exactly.

480
00:24:10,160 --> 00:24:11,200
DAVID J. MALAN: Well, from
the looks of the video

481
00:24:11,200 --> 00:24:13,660
it sounds like it was a
pretty exhausting trip.

482
00:24:13,660 --> 00:24:16,307
It sounds like you didn't
really have much time to relax.

483
00:24:16,307 --> 00:24:17,390
RAMON GALVIN: Not one bit.

484
00:24:17,390 --> 00:24:20,084

485
00:24:20,084 --> 00:24:22,000
DAVID J. MALAN: Well,
that's it for CS50 Live.

486
00:24:22,000 --> 00:24:23,830
Thanks so much to this
week's contributors.

487
00:24:23,830 --> 00:24:25,870
Thanks so much to the
team behind the camera.

488
00:24:25,870 --> 00:24:27,880
Thanks so much to our correspondent--

489
00:24:27,880 --> 00:24:28,755
RAMON GALVIN: Senior.

490
00:24:28,755 --> 00:24:30,880
DAVID J. MALAN: Senior
correspondent in the field.

491
00:24:30,880 --> 00:24:32,880
This was CS50.

492
00:24:32,880 --> 00:24:35,480
>> RAMON GALVIN: And this is
something, I don't know what.

493
00:24:35,480 --> 00:24:38,030
>> DAVID J. MALAN: It was
our dress rehearsal.

494
00:24:38,030 --> 00:24:39,230
So that all sounds great.

495
00:24:39,230 --> 00:24:42,030
Bigger TVs, more
pixels, more resolution.

496
00:24:42,030 --> 00:24:43,740
But why is this actually useful?

497
00:24:43,740 --> 00:24:45,240
>> RAMON GALVIN: I'm glad you
asked that question, David.

498
00:24:45,240 --> 00:24:48,110
>> DAVID J. MALAN: I'm glad you asked--
I'm glad I asked you to ask me that.

499
00:24:48,110 --> 00:24:50,060
>> RAMON GALVIN: No, I say I'm
glad you asked me the question.

500
00:24:50,060 --> 00:24:52,220
And then you say, well
it's in the prompter.

501
00:24:52,220 --> 00:24:54,149
I'm glad I asked you to
ask me that question.

502
00:24:54,149 --> 00:24:56,190
DAVID J. MALAN: Well, it's
in the prompter there.

503
00:24:56,190 --> 00:24:56,870
RAMON GALVIN: I'm glad you--

504
00:24:56,870 --> 00:24:57,840
DAVID J. MALAN: I think it's
funnier if you just say,

505
00:24:57,840 --> 00:24:59,852
I'm glad I asked you to
ask me that question.

506
00:24:59,852 --> 00:25:02,060
Because it's kind of a play
on what you would expect.

507
00:25:02,060 --> 00:25:02,990
>> RAMON GALVIN: OK.

508
00:25:02,990 --> 00:25:05,750
I'm glad you asked me to
ask that question, David.

509
00:25:05,750 --> 00:25:06,780
There's a documentarian.

510
00:25:06,780 --> 00:25:08,738
>> DAVID J. MALAN: I'm glad
I asked you to ask me.

511
00:25:08,738 --> 00:25:11,600
RAMON GALVIN: I'm glad I asked
you to ask me that question.

512
00:25:11,600 --> 00:25:39,627
>> [MUSIC-  CAKE, "THE DISTANCE"]