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Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

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31–40 of 262 posts

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#32
post #30

Why not have a deferred compressor? I assume that just straight-up saving the raw data in memory would be much faster than compressing every frame as you get it. Couldn't you get significant FPS increases (given that you still had free space/memory available)?

Actually, I do both on dual core devices.

One core is dedicated to host the capture/buffer, the other will encode shots in the background.

When you see the big circle percent animation, both cores are dedicated to compression to clear the encoder queue so you can take back to back living photos quickly.

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#33
post #31

Looks like they've an instagram-type site set up too. http://snappyc.am/2LdRMF28U0 http://snappyc.am/4HHxyCad7D http://snappyc.am/3G3i6QCJUk

Nice find! It's going to form part of the Facebook Timeline integration that's coming soon... as well as embeds, though Josh already linked to the "press samples" page in the article. :-)

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#36
post #32
post #30

Why not have a deferred compressor? I assume that just straight-up saving the raw data in memory would be much faster than compressing every frame as you get it. Couldn't you get significant FPS increases (given that you still had free space/memory available)?

Actually, I do both on dual core devices. One core is dedicated to host the capture/buffer, the other will encode shots in the background. When you see the big circle percent animation, both cores are dedicated to compression to clear the encoder queue so you can take back to back living photos quickly.

Very cool :) Thanks for the quick reply.

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#37
I'm interested to know how their method compares to how dedicated digital cameras and DSLRs do it? are cameras running dedicated hardware/firmware to achieve the same result? Or have they optimised their software in the same way that SnappyCam has done it?

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#38
post #16

Earlier quoted context omitted.

You are right on the loss: it's purposefully introduced as a quantization step after performing the DCT, and before losslessly compressing the resulting coefficients with Huffman and encoding to the final JPEG bitstream. Despite all of that, JPEG has now become computationally tractable. I remember the days where it took tens of seconds to encode a JPEG on a commodity machine. Now, with the help of SIMD, we can encod…

It's just bizarre that you would be doing the complete JPEG process at the instant you get the image from the sensor. As you note, there are a plethora of steps that JPEG performs, from color space conversion, to DCT transformation (essentially a gigantic matrix multiplication), Huffman coding, quantization, arithmetic coding and encoding as JPEG bitstream. The only reason would be that you are pressed for memory or…

Oh, I actually do both---see the other thread on the topic.

I buffer as much as possible, while also encoding on any other cores that are available.

There's a reason why a "simple camera app" can total some 80 kLOC. :)

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#39
post #35

This is quite remarkable. I just tested it and works even better than advertised. I hope you become rich and famous for this. And I really hope there's not a hidden gotcha I haven't seen yet.

Thanks! :D I'm just very happy to have more people try the app.

It's been a hard slog working 7 day weeks for just over two years now. Feels great to receive some kind of recognition for the work.

Re: Scientific Breakthrough Lets SnappyCam App Take 20 Full-Res Photos Per Second

#40
post #25

I have a feeling that soon SnappyLabs is going to have Apple knocking on their door with a very nice offer. Kudos to them, sounds like they deserve it.

Thanks!

I just hope Apple's engineers don't get pissed off by the press. SnappyCam is built on their hardware, which can do remarkable things.

Though we as app developers don't get access to a lot of their smarts, e.g. hardware JPEG codecs, I'm sure there's even more innovation in their work that often goes unacknowledged.

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