Welcome to the Vergecast, the flagship podcast of Looking for Naked Singles. I'm your host, Allison Johnson, and that makes sense in this context. I promise it is a Sudoku thing. And on today's episode, I'm talking to a couple of world champion puzzle solvers who started their own YouTube channel where they solve a Sudoku every day. They're ridiculously hard and surprisingly fun to watch. After that, I'm talking to Mark Levoy, who's one of the pioneers of computational photography and really just phone camera technology in general. We're going to talk about his new camera app called Project Indigo. That's all coming up right after the break.
All right, we're back. I am joined by two very special guests. Simon Anthony. Hi, Simon.
And Mark Goodliffe. Hey, Mark.
They are puzzle champions, but more importantly, the hosts of a YouTube channel called Cracking the Cryptic. And I guess I'll let you guys explain what that is, what you do there. Simon, maybe can you give our listeners a quick rundown if they're not familiar?
I can, but it'll sound mad.
Cracking the Cryptic is a YouTube channel where we solve variant Sudoku puzzles sort of live on camera a couple of times each day. And the channel's been going now for about 8 years and it's become like really quite popular. So we have about 650,000 subscribers now and the average length of a video is perhaps 45 minutes to an hour. So people are spending time with us every day having a go at these puzzles and then watching us attempt them. And because it's live, it's all of the mistakes, you know, all of the poor thinking is there, but in the end hopefully we solve the puzzle and that's what we do. And we each post a video every day and in addition to that there's a weekly cryptic crossword masterclass as well and we solve Wordle every day as well. So there's a lot of content and it keeps us very busy.
I really appreciate the Wordle videos. They make me feel, they usually make me feel better. Like, okay, this wasn't as easy as I thought it was. And if you could explain really quickly. So, I discovered your channel because I got into Sudoku. But I am more familiar with, I think, what you call classic Sudoku. Could you explain just the basics of classic Sudoku if people are not familiar, but also how it escalates from there and the kind of puzzles that you guys tackle.
Sure thing. So in normal Sudoku you get a grid of 9 by 9 cells and you have to put the digits 1 to 9 once each in every row, every column, and then there'll be nine 3x3 boxes in the whole 9 by 9 grid and each of those 3x3 boxes mustn't have a repeated digit either. And that's the game that I think most of us were familiar with when it first came to the West, I suppose, which was in the early 2000s. And variant Sudoku takes that and sort of turns it up to 11. So you might have extra graphics in the grid. There might be a thermometer wending its way through the grid and you'll have to increase the digits along the thermometer from the bulb end. And then it can get crazier and crazier from there. We've got puzzles now where there's a rat in the grid that has to get to a cupcake going along certain pathways. We've got puzzles where most of the grid is covered in fog and you can't see it. But when you get a correct digit, some of the fog will clear and so the puzzle is revealed to you gradually. And these puzzles have all been handmade. So they're very, very different to most people's experience of Sudoku, which will be on the back of newspapers. All of those puzzles are made by computers. Whereas the moment you solve a puzzle that's been created by one of these fantastic human brains, it's a different experience altogether. And I think that's why the channel has become popular, is people are suddenly seeing just the art that can be found in the puzzle form.
I find that so interesting because maybe one of the things I do when I get into a thing is be like, how is this made? I want to take it apart, you know. So maybe if you could talk a little bit about how you mentioned a lot of classic Sudokus are computer-generated. Were they always like that? Is this like a recent thing? And how can you tell the difference, you know?
Well, I mean, originally the puzzle was invented in Japan by a company there called Nikoli, which is a wonderful place of innovation and all of their puzzles are handmade. But when the puzzle came to the West, it was Wayne Gould originally, I think, a New Zealander who invented a computer program that could just churn out zillions and zillions of puzzles and he managed to sell it to many of the newspapers in the Western world. And so it just became accepted that, you know, you could have computer puzzles and everyone seemed fine with that because they'd never experienced anything different. Whereas when you solve a Nikoli classic Sudoku, so the classic Sudokus that you were originally used to, Allison, you know, when you solve one of these Nikoli puzzles, it's completely different because the constructor has built into the puzzle sort of a trail of breadcrumbs and you can feel what they want you to find at the particular points and there's normally some really beautiful logic packed in there which you just don't find in the machine-generated puzzles. So, yeah, it's a big difference.
Yeah, when we started the channel, we were mainly solving classic Sudokus from, say, the New York Times or something and they would all be computer-generated and they would often have a very standard kind of trick to get them done and we would go through that. But then gradually as we got going, we wondered would it be interesting to show people the sort of variant Sudokus from world championships that we'd experienced that were a bit more interesting in a way. And unbelievably this whole community grew up watching these puzzles, watching these videos and going, oh no, that's really interesting Sudoku. And I think almost all the setters that we feature on the channel now, and we basically take submissions from people as a good puzzle to do on the channel, almost all of them grew up, learned about variant Sudoku from our channel. So it's marvelously organic in a way.
Yeah. I was wondering if you could talk a little bit about the community because I think there's an interesting moment, you know, with any kind of creator on the web, you know, whether you run a website or a channel, where we're sort of discovering just the real value to having a community and that's kind of what people want. So, how do people connect with you? You mentioned they suggest puzzles, but how else are you interacting with your community?
Well, it's one of the things that happened to us. You have to bear in mind, we're sort of middle-aged guys. We're not tapped into things like Discord. But when the channel started to get bigger, we got approached by some people who watched it who said that you really should have a Discord channel associated with your YouTube channel. And we were like, oh, that sounds good. And they said, oh, we'll take on the sort of role of setting it up for you. And we thought that that would be nice. I think there are now nearly 40,000 people in this Discord server. And all trading ideas, all solving puzzles for each other, trying to push forward the boundaries of what's possible in Sudoku. I mean, I shudder to think what the combined IQ is of the people on there, but there is some serious weaponry in terms of intellectual firepower. And one of the lovely things about Cracking the Cryptic is that actually the community is remarkably kind. It's something we've always encouraged, you know, kind comments, positivity, and people really seem to take that to heart. And I think most of the internet now is probably a place where blood pressure gets raised, whereas Cracking the Cryptic is a place where it sort of gets calmed a bit. And it's attracted people to it who are in general very decent and normally very bright as well. So we get a lot of impostor syndrome, at least I do.
Oh my gosh. I mean having to solve everything live and kind of be on your feet like that. Is it a challenge every day? Do you get kind of nervous? How does it...
It is daunting. It is a worry that you sit down in front of a puzzle and if it goes wrong, I mean, if it goes completely wrong and you can't solve it, we don't have to put up a video. So there's always that get-out. But that's kind of a rarity, I think, for both of us. And most of the time, if you do make a mistake, well, you have to kind of backtrack and find it and work out what you did wrong. And people are very generous about that as well. I think as Simon said, the levels of kindness are very high and the great setters and theory creators seem very keen to still interact with us even though I suspect we've been revealed as not the great brains that people maybe thought we were at the beginning. But it is just a pleasure to deal with almost everybody on the site through Discord, in the comments. We get emails. We put our email address out every day and we get hundreds of emails. As I say, puzzle suggestions, but also lots of general comment. I think we were amazed at the beginning when it started to grow and people would tell us something like, oh, I fall asleep to you every night. And we weren't sure whether that was a compliment or an insult. But gradually there was a period, and it's probably still ongoing, where we get about one email a day about how we've seriously helped someone's mental health, you know, from extreme levels of stress sometimes. And we've had at least three doctors tell us that they would have given up their course, but the calm logic that we allowed them to see enabled them to keep going in their studies. And it's just an amazing thing to have that kind of impact with no thought or plan of doing so.
Yeah. It kind of strikes me as like solving a puzzle is a pretty solitary activity. I mean, it kind of has to be unless you're doing a jigsaw puzzle with your friends or something. And sort of personal in a way. Like when I sit down to do Wordle every morning, I feel a little embarrassed to like show other people my guesses. You know, it's sort of like when you're ordering a pizza on the phone and I don't want anyone else to hear me like working this out. So I wonder if there's an element of just it feels like you're exposing something a little bit and people are connecting to that in a way where it resonates, I guess.
I think there's definitely something to that. I mean, it is nerve-wracking to actually solve and because all of the thinking you're doing is live. I mean, I still get this shot of adrenaline if I have to do mental arithmetic because some of the arithmetic we have to do, you know, you could be multiplying some reasonably big two-digit numbers or something like that or you might be having to find the prime factors of something that's not trivial. And you're sort of there thinking people are going to be watching me thinking he's so stupid. Why can't he do it more quickly? And you know, you've got this devil on your shoulder the whole time chirping away about how you're being dumb. And you have to ignore him because he's just a very annoying creature. But he's definitely there.
Yeah, we also have different strengths. I think, Allison, sometimes I marvel at Simon's instinct for a break-in in a puzzle that's complicated to start. And I just can't see how he's honing in on the right spots as he so often does. He's, I understand, jealous of my sort of basic Sudoku mechanics and maybe some of that mental arithmetic as well. But you know, these are the skills that I think are trivial whereas he has skills that, you know, I can sit in front of a really hard puzzle for 20 minutes, half an hour, 40 minutes just not knowing what to do and it just feels dreadful in a way. But you learn over time that if you keep worrying away at it, you can. And this is very important to remember that the constructors are setting you a puzzle that they want you to have fun with and struggle with but they want you to get there. So there is this trail of logic to find and when you do light on it, you get this wonderful epiphany and I think that's what keeps people coming back to the channel is watching those moments where you suddenly understand something and that's joyful.
No, hang on. Maybe it's... No, it is the same. If that's a six, I can't put a one here. And this is a six in box five, which puts a one here. So, you can't put a one either side of it. So, here we go. So, now I know that there's a six in this domino, which means this is not a six. This is a six, which means this is a one, this is a two, and we are cooking with gas all of a sudden.
Yeah. And I kind of see, I don't know if I'm just like keying into this because I've been interested in Sudoku. But there's a lot of like puzzles seem to be having a moment. Like I know a friend of mine is addicted to the puzzles in the LinkedIn app and like opens LinkedIn every day. And I'm sure there's an element of they've discovered, you know, they can keep people coming back every day and get those like daily user numbers up. But what do you think that says about like maybe our moment culturally or what puzzles are doing for people?
I think there's a lot to unpack there. I mean, I think LinkedIn has really, it dodges most office firewalls, of course, which means that it's absolutely brilliant if you enjoy having a few minutes out every day. A lot of puzzle websites tend to be blocked from my experience, but LinkedIn probably won't be. So that's a good thing. But I also sense that there is being a bit geeky or nerdy, which I've been throughout my life. I mean, same. Yeah. I've never been cool, popular. I mean, my sister has relished throughout my life, you know, telling me how useless I am in all social situations. But now it just feels, I don't know whether it's AI or, you know, computer programming becoming, you know, it's everywhere, isn't it? So necessary for so many parts of life. But it feels like, or the popularity of things like escape rooms as well.
Or maybe it's the mindfulness that comes with doing puzzles, as you've found. You sort of, when you actually have to focus on a puzzle, you're taken away from maybe the worries of life for a few minutes. You have to focus on what you're doing or you probably won't get very far. And it brings a calmness and maybe people value that in this day and age more than they perhaps would have done 15, 20 years ago.
I think the way you expressed it, Allison, is absolutely right. Puzzles are having their moment. But in a way what it is, is I think people are in this moment discovering puzzles and finding out how much fun they are. I come from, originally before Sudoku, from a world of cryptic crosswords and people have often asked me why, you know, why are you doing, or now it's obvious, but in the old days they would ask me why are you doing this old man's pursuit and I was saying well it's not, doesn't have to be. Basically once you find the joy of cryptic crosswords there's no reason ever to stop doing them and people don't. And therefore the average age tends to skew older than for pursuits that people will give up when they've had their fill. But you don't do that. And I think it's true about Sudoku as well. People stay with it. Even if they don't stay with our channel, I think they stay with Sudoku and with puzzles. And it's, you know, we've been part perhaps of leading people to discover puzzles. And that's great. And I think it's more that people are sort of free to enjoy them now rather than that they hadn't thought of them before.
I'm curious actually about kind of the tools you use in your puzzles because I think maybe Simon, you mentioned in a video that you sort of prefer puzzles that you can just think through and there are tools that exist for super hard Sudoku that like help you math your way out of it. I don't know. Can you kind of talk me through like the tools you do and don't use when you are solving puzzles?
Yeah, I mean I think we both use computers obviously because we're recording something we're doing on a computer. We have some great software that's been created by Sven Nusbaum which is very, very good. It allows us to employ some techniques that are much harder to do if you've just got a pencil. So, for example, we can color in cells. Or we could even draw lines through cells. And when we're solving these harder puzzles, things like that, they're pretty useful. The software even, I mean, we don't use it, but it'll allow you to compute all the different ways of adding up to 25 with four digits. It'll actually give you a list of all the ways that you can do that. So if you don't like doing the arithmetic, you can still access the puzzle. But I think as with anything, what you find is you build up your own personal tool of, I don't know, tricks, techniques, and you cycle through those. And that only really comes with experience. And I guess now Mark and I have a lot of experience. So we've got something like 4,000 videos now. Mark, I was...
I think it may be 5,000 now.
Yeah. Yeah. There's a back catalog.
Yeah, it is. You do build up a lot of experience and it's often very helpful. And yet still every few months something completely new is kind of forced in upon us by a brilliant constructor and we learn something totally new, even sometimes about a basic Sudoku grid, that it must have some property that we didn't know before. And that's, you know, I still think in some ways this is the dawn of Sudoku, which is brilliant.
Yeah, Mark's right. I mean there was a mad thing we discovered the other day for the first time which is sort of if you imagine that you've checkerboarded your Sudoku, the sort of internal checkerboard you've created, any digit you put in that has to appear an even number of times in that internal checkerboard. Which it's like, why is that true? And yet sort of geometrically, mathematically it is true, but we didn't know it. I didn't know it before I did that puzzle. It was completely, it's like it's a truth that exists underneath the surface of the puzzle. It's not going to help you solve a classic Sudoku, but it's there and it's just sitting there like a mathematical truth. It's extraordinary.
Yeah. There is something really satisfying, I think, in discovering new layers of something you've been enjoying. I do want to touch on a puzzle you did. And this was, I guess, went viral. We wrote about it on The Verge. This was the Miracle Sudoku. Is it right? Can you, and Simon, you solved this one. Can you describe what this puzzle was and kind of how it went?
Well, I can, I mean, but really it was Mark's fault. So what happened was we got sent a puzzle by a constructor called Mitchell Lee. And the very unusual thing at the time about this puzzle was it looked like a normal Sudoku except rather than having several digits in the grid, there were only two digits in the grid. There was a one and a two and that was it. And Mark sent me an email and said, it would be good if you opened this live on camera. So, I took him at his word, set up my machine, loaded it, having started the recording, and was faced with this. At that time, it just looked stupid. I thought he'd just done it as a joke. And so, I very nearly, thank goodness I didn't, I very nearly turned off the webcam and sort of called him in high dudgeon. But no, I could see one thing at the start that I could possibly do. And so I did the thing and then just, it was amazing. After, you know, a few more steps, I could see something else. And it was one of those puzzles where you sort of, it was like a snowball, you know, starting an avalanche. All of a sudden, this pattern emerged and at the end I did solve it. Let me just see if I can put that in there. Let's see what we get. Right. He's got to be joking. There is no way that this... Well, it might have a unique solution, but it's not going to be findable by a human being. I suspect this is going to be a short video because he is trolling me. I think the reason it was popular was just my sheer astonishment that this could exist, that you could, yeah, that somebody had had the idea, that somebody had made it, and also that this impossibility was actually solved in about 25 minutes. It was just bizarre. It was bizarre.
Exactly my finding when I tried it before Simon had seen it.
Yeah. And something, if people aren't familiar with the channel, you can solve along with these puzzles. So that's exactly what I did, you know, watched you get started with it and then yeah, you look at it, you're like, there's no way this could be solvable. But I saw you, you know, go through the first kind of steps and tried it on my own and it, you know, I had to like rewind a couple times and see what you were doing. But it's so cool to kind of go on that journey with you where I'm like, oh my god, I am solving this. Yeah, it just, I had a lot of fun with it.
Yeah. I mean, it was remarkable. I mean, we got emails from all over the world as a result of that. It was like a moment where, you know, they say everybody has their 15 or five minutes of fame. It was like that spotlight suddenly turned on us for just a scintilla of time and you sort of got a bit of the glare of a little bit of publicity and it was very enjoyable because it was so brief and unexpected.
Yeah. And a positive, I think, you know, if people are discovering it and having like a joyful moment of like, I can't believe I just watched this 25-minute-long video, which is I think interesting. And you kind of touched on this, I think, that your videos are long, like, you know, comparatively in the age of like certainly TikTok where you watch for a few seconds and scroll on. Can you talk a little bit about why you think you're able to enjoy, you know, having such a long amount of time to show what you're doing and talk about what you're doing.
And we thought that people would just want to see the technique, would just want the lesson. And then we kind of thought, well, they won't want to watch the rest of the solve. That's just filling in the numbers. And we would try things like speeding it up or putting music to it. And they got really annoyed. They said, no, no, no, no. We want to see you solve it till the end.
And it is, I think it's what you said earlier, that people want to come on the journey of the solve and they want to be part of it all the way. Some people treat it like sport, like a spectator sport, and until you put the last digit in, the final whistle doesn't blow. So, it's still going. And that extends into the longer videos. I mean, Simon's done videos. Is it three hours you've done now, Simon?
No, I've done four hours 10 minutes is the longest puzzle.
And you'd think, oh, that can't be popular because how can it possibly be the case that anybody would want to watch a man solve a Sudoku puzzle for longer than the extended edition of Return of the King or something. It cannot be right. And yet it's one of our most popular videos of recent times. People get invested in it. And then in fact on that video is one of my favorite comments underneath the video that we've ever had, which was from a guy and he said, 15 years ago I watched the whole of the Twilight series with my girlfriend on the condition that one day she would watch something of my choice without complaint. Tonight's the night.
Oh my gosh. I love that. Yeah, personally I'd rather watch four hours of puzzle solving, but yeah, I can see how that trade was made.
Incredibly, those long videos get more average watch time percentage than the shorter ones. It just defies belief, but people do enjoy the... I think they love seeing us challenged. They love the struggle because they're being challenged as well at the same time. And you know, it's to an extent of seeing what the human brain can achieve, and I'm talking about the constructors more than us, but there's us as well.
Well, thank you so much for joining me. This was a delight and I hope people will check out Cracking the Cryptic on YouTube. And I'm going to be seeing you again soon because I'm going to be watching your videos.
Thank you. Thanks, Allison. It's been a pleasure.
Yeah, absolutely lovely. Thanks, Allison.
We need to take another break. When we come back, we're going to be talking to Mark Levoy about his new camera app, Project Indigo. It's coming right up.
Welcome back. I am joined by someone who for a portion of our audience will not need an introduction, but we'll do one anyway. I'm here with Mark Levoy. Hey, Mark.
Thanks for joining. Mark Levoy is a professor emeritus of computer science at Stanford. But right now, and what we're going to be talking about, he is a VP and fellow at Adobe where he has been working on a new camera app. Also known to a lot of people in our audience in particular for his work on Google Pixel camera for many years. So thank you for joining me.
So, I was wondering if you could give us maybe a shortened version of your bio. There's a lot of interesting stuff on there, you know, some of which I just touched on. But then catch us up a little bit on what you've been doing since you've been at Adobe.
Shortened version of the bio. Well, so I seem to have wandered from topic to topic roughly every 10 years. So, in the 70s I worked on computer-assisted cartoon animation at Cornell. In the 80s, I worked on medical imaging at University of North Carolina. And then at Stanford in the 1990s, I worked on three-dimensional scanning, including the Digital Michelangelo project. In the 2000s, I worked on light fields and camera arrays. Built some big camera arrays at Stanford. And in the 2010s, largely at Google, I worked on computational photography, including, as you said, for the Pixel phone.
Yeah. And you joined Adobe in 2020, is that right?
Right. During the height of the pandemic.
Ah, an interesting time to switch jobs. I did it, too.
Yeah. So I think, and you spoke to our editor-in-chief, Nilay Patel, around that time and the stated goal was to create a universal camera app. And it's been five years since then, you've released that camera app called Project Indigo. Can you give people the quick elevator pitch if they're not familiar with it? I know a lot of our audience is.
Depends how long the elevator is. So the basic idea there is there are a number of limitations of most smartphone camera apps. There's a smartphone look that a lot of people don't like that might look okay on the small screen or in bad lighting but don't look okay if you look at that same image large. It's very bright. It's contrasty. The shadows have been raised a lot. The edges are very sharp. The saturation is boosted. It's a certain look. As I said, it might look fine on your screen, but not if you're trying to make something larger out of it or even look at it on a large screen. Another issue with most smartphone camera apps is they don't offer much in the way of manual control. Some of the third-party apps do, but then they don't offer the third thing, which is computational photography. So by computational photography, I mean combining multiple images to make a better quality image regardless of the look. So we wanted to combine all three of those things: a more natural look, full manual controls, and the best computational photography the state of the art allows. We also wanted to release some fun stuff on the side. So we have synthetic long exposure. We have removing window reflections, which also ships in Lightroom and Camera Raw.
