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Pixar in a Box – Khan Academy

pixarinabox.org

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Re: Pixar in a Box – Khan Academy

#51

Post by lighttower »

merpnderp wrote: post #42
drewblaisdell wrote: post #6

Earlier quoted context omitted.

Not a comment about this specifically, but I'm a big fan of your other courses on Khan Academy. They changed the way I think about the world. I can't overstate how grateful I am that you created them. Everyone should check out these lessons: Journey into cryptography: https://www.khanacademy.org/computing/computer-science/crypt... Journey into information theory: https://www.khanacademy.org/computing/computer-science…

I can't believe you just posted this. I had a 5 hour drive this morning and listened to nearly all the cryptography lectures during it.

Hey. Is there a way to extract the audio so I can listen to it from my phone? The links above point to flash content that I can't access on mobile

Re: Pixar in a Box – Khan Academy

#53

Post by lqdc13 »

wbhart wrote: post #16
Paul_S wrote: post #11

Earlier quoted context omitted.

I'm trying out different videos and I can't find ANY instructional content in them - I mean in terms of technical information, something applied that you can learn and use. It feels like watching a TED talk and not a Khan academy lecture!

I just watched the first two sequences of videos and so far they have shown how to compute midpoints of lines and how to compute the coordinates of points on parabolic arcs given three arbitrary control points, including how to prove the identities involved. They then explain how this is used in practice to generate the shape of a blade of grass. Is this not the kind of technical information you were expecting to fin…

I guess it would be great if there was some sort of application that let you apply these techniques and actually see the results.

Otherwise, it's like reading the theory section of documentation without getting to use the program.

Re: Pixar in a Box – Khan Academy

#54

Post by ryanmonroe »

lighttower wrote: post #51
merpnderp wrote: post #42

Earlier quoted context omitted.

I can't believe you just posted this. I had a 5 hour drive this morning and listened to nearly all the cryptography lectures during it.

Hey. Is there a way to extract the audio so I can listen to it from my phone? The links above point to flash content that I can't access on mobile

There are lots of websites that will extract mp3s from youtube videos which you'll find if you just google "youtube to mp3". There are also browser extensions which do this. Here's one:

http://www.video2mp3.net/extension.php

Re: Pixar in a Box – Khan Academy

#56

Post by Xunxi »

lighttower wrote: post #51
merpnderp wrote: post #42

Earlier quoted context omitted.

I can't believe you just posted this. I had a 5 hour drive this morning and listened to nearly all the cryptography lectures during it.

Hey. Is there a way to extract the audio so I can listen to it from my phone? The links above point to flash content that I can't access on mobile

If its android you can try this http://www.snaptube.in/

I use it for everything including X rated content from adult sites

Re: Pixar in a Box – Khan Academy

#57

Post by britcruise »

lqdc13 wrote: post #53
wbhart wrote: post #16

Earlier quoted context omitted.

I just watched the first two sequences of videos and so far they have shown how to compute midpoints of lines and how to compute the coordinates of points on parabolic arcs given three arbitrary control points, including how to prove the identities involved. They then explain how this is used in practice to generate the shape of a blade of grass. Is this not the kind of technical information you were expecting to fin…

I guess it would be great if there was some sort of application that let you apply these techniques and actually see the results. Otherwise, it's like reading the theory section of documentation without getting to use the program.

All of our lessons give you interactive tools to create and experiment with in various ways. For example this one is fun: https://www.khanacademy.org/partner-content/pixar/modeling-c...

Re: Pixar in a Box – Khan Academy

#58

Post by alangpierce »

merpnderp wrote: post #42
drewblaisdell wrote: post #6

Earlier quoted context omitted.

Not a comment about this specifically, but I'm a big fan of your other courses on Khan Academy. They changed the way I think about the world. I can't overstate how grateful I am that you created them. Everyone should check out these lessons: Journey into cryptography: https://www.khanacademy.org/computing/computer-science/crypt... Journey into information theory: https://www.khanacademy.org/computing/computer-science…

I can't believe you just posted this. I had a 5 hour drive this morning and listened to nearly all the cryptography lectures during it.

I'm a developer at Khan Academy (currently working on the upcoming Android app), and it's cool to see that there's real interest in that kind of use case! In our hackathon a few weeks ago I wrote an audio-only Khan Academy app that lets you listen to any video or the text-to-speech of any article and is controlled completely through voice commands. Unfortunately it's not quite at a point where other people can use it, but maybe I'll take the time to actually productionize it. :-)

Here's the code if you're curious:

https://github.com/alangpierce/Audicademy

And there's a feature-incomplete web version that lets you navigate to any video and play it (requires a recent version of Chrome):

https://audicademy.appspot.com

Re: Pixar in a Box – Khan Academy

#59

Post by a_e_k »

tbabb wrote: post #36
ska wrote: post #27

Earlier quoted context omitted.

Isn't that complimentary to what I said though? You could presumably get the same result by just path tracing the whole thing, so all you've gained is speed at the cost memory. I didn't mean speed hack in a pejorative way. I understand why you might want to do this in practice, but it still doesn't seem to be that important to teach as an introduction.

The difference between Reyes and path tracing is this: - Reyes batches camera-visible geometry into grids of micropolygons and microvoxels. These micro-elements are then shaded using any method you please (which, in the case of Pixar movies since Monsters University, has been raytraced physically based illumination). The micropolygons are projected to the image plane and stochastically sampled, much more akin to trad…

All good points. I'd also add:

* Discarding data when finishing a bucket means that you have to produce final-quality pixels before moving on. Path tracing allows the renderer to produce an initial, crude pass over the pixels and then refine from there. This leads to quicker initial feedback and makes interactivity possible.

* Object instancing is much more practical with ray tracing.

* Before hybrid REYES/ray tracing, you'd have to bake out shadow maps and other passes before you could get to the beauty render. Even with ray tracing you might still be baking point clouds for GI. With path tracing you can do it all with one render pass.

Re: Pixar in a Box – Khan Academy

#60

Post by vertis »

alangpierce wrote: post #58
merpnderp wrote: post #42

Earlier quoted context omitted.

I can't believe you just posted this. I had a 5 hour drive this morning and listened to nearly all the cryptography lectures during it.

I'm a developer at Khan Academy (currently working on the upcoming Android app), and it's cool to see that there's real interest in that kind of use case! In our hackathon a few weeks ago I wrote an audio-only Khan Academy app that lets you listen to any video or the text-to-speech of any article and is controlled completely through voice commands. Unfortunately it's not quite at a point where other people can use it…

Audio only is a big thing for me. Commuting to work is a key learning time, and mostly audio is the only workable option.
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