
Prisma: neural-style instagram filters - volodia
http://thenextweb.com/apps/2016/07/08/prisma-app-mindblowing/#gref
======
cloudwalking
I found it interesting that all of the rendering is done server side. If you
turn your phone into airplane mode, the app no longer works. I suppose it
makes sense -- a server provides more flexibility in how you do the heavy
lifting (is it in fact a neural network?).

~~~
qubex
It always irks me when I discover that an ’app’ for an apparently
’computational’ (and localisable) task is nothing but a client for logic that
resides and runs elsewhere: it means that the idea of having a free-standing
program is an illusion and _that if something happens to the company the app
will stop working_ rather than merely become abandonware.

So yes, it might make sense, but it is at some level disappointing.

~~~
Asooka
Eh.. in this particular case it really makes sense to do it server-side. A
beefy core i7 can take a couple of hours to do the style transfer and you
ideally want a farm of GPUs to handle the client requests. Doing it client-
side on the phone would absolutely drain your entire battery and take half a
day or more.

~~~
iverjo
They are probably using a newer approach, where they pre-train a neural
network and use forward propagation only. With this technique, applying the
effect can take less than one second. See
[https://github.com/DmitryUlyanov/texture_nets](https://github.com/DmitryUlyanov/texture_nets)
for more details. You can also try it here:
[http://turbo.deepart.io/](http://turbo.deepart.io/)

------
rayalez
There's an excellent website, [http://deepart.io](http://deepart.io), it does
the same thing, and allows you to upload your own image to use as a style.

------
matthewrudy
It's really great that someone is productising this technology so quickly.

It was only a few months ago that this involved grabbing a repo off github,
and working out how to process it yourself.

Now I'm seeing this stuff being posted by non-technical friends on my facebook
feed.

I want to see how well the video works, as it seems that's only been solved
recently.

[http://arxiv.org/abs/1604.08610](http://arxiv.org/abs/1604.08610)
[https://www.youtube.com/watch?v=Uxax5EKg0zA](https://www.youtube.com/watch?v=Uxax5EKg0zA)

------
j2kun
IIRC you only get to choose from a fixed set of styles to process your image,
right? Then they're probably using this algorithm to precompute the style
model and seriously speed up rendering:
[http://arxiv.org/abs/1603.08155](http://arxiv.org/abs/1603.08155)

------
kirtant
I am really amazed by the results on the article! Eagerly waiting for Android
version! There is also one open-source lib like this
[https://github.com/jcjohnson/neural-
style](https://github.com/jcjohnson/neural-style)

