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

techcrunch.com

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

#101

Post by jpap »

gosu wrote: post #96
jpap wrote: post #95

Earlier quoted context omitted.

@gosu, despite what Josh wrote, you can traverse your pointer across any part of the living photo online. :-) Love that you picked up on the expressions! It wasn't until I got the photos out of the app was I fascinated by the same thing. I really can't wait to enable this functionality for everyone soon. :-) More elaborate mouse movements are possible, only in HTML5 full screen mode; required to "capture" the mouse (…

facepalm What was happening is that I was trying to keep the mouse in the control strip, and it would go off the right side of the image. Thanks a lot, Josh. Edit: By the way, the fullscreen functionality isn't launching. But I do have a weird browser (conkeror on xulrunner 22.0).

haha, no worries.

In the app, you need to start with your finger near the thumbnail strip. (But can move it away for fine-grained scrubbing if you wish.)

It's no surprise that the learned behavior is transferring to the web viewer.

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

#103

Post by jpap »

chacham15 wrote: post #99

It looks great but I have a few questions/comments. 1. What is the difference in quality between using this and the video capture mode? I.e. if what I really want is a high quality video, would this get me a better result than the built in programs? 2. Seeing as how you've done all this work (and how Android apps can be compiled from C) how difficult is it to port this to Android so that the rest of us can get in on…

1. It really depends on what you're after: are you looking for a video sequence that plays back, or an individual still? Video is better for the former, SnappyCam for the latter.

2. It's a lot of work, hinted at in another thread here on HN. The entire "app" build on top of the JPEG codec needs to be built from scratch; new artwork is required, etc.

3. I just tried it from another machine and works for me.

My backend API is being hammered at the moment, which is awesome, but it doesn't appear to be overloaded. (Gotta love NodeJS!)

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

#104

Post by jpap »

pdog wrote: post #89
jpap wrote: post #64

Earlier quoted context omitted.

Thanks mate---comments like yours make my day. :-) I'm not actually planning on creating a new niche social network. I think, given the vastness of some of the ones that've emerged of late, it would be more fruitful to leverage the ones that exist today. Can't wait for you to see it!

Given that niche social/mobile networks for short videos are so hot right now (ie. Vine, Instagram Video), it might be more fruitful for you to plan on creating a new one.

The Cinemagram guys started off down that path, an Instagram clone for animated GIF cinemagraphs, then quickly pivoted toward short videos to compete with Vine and Instagram on similar territory.

I'm still not convinced. :-)

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

#105

Post by jpap »

est wrote: post #67
jpap wrote: post #62

Earlier quoted context omitted.

I thought the app was pretty cool, just super slow to save out the JPEGs. That's one of the reasons I spent a lot of time to make sure SnappyCam could compress these images, thumbnails and Exif metadata included, at a ridiculous speed.

Yes, SnappyCam has a faster algorithm advantage. Android on the other hand, has more open and better hardware, e.g. larger full-res camera, much larger RAM, faster external storage or even OTG, more CPU/GPU cores. In theory if SnappyCam is full ported to Android you can make it faster than 8M pixels @ 20fps

The possibilities are exciting for sure! :-)

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

#106

Post by binarycrusader »

jpap wrote: post #21
0x09 wrote: post #13

Earlier quoted context omitted.

So the summary is "JPEG encoder written in assembly with NEON instructions saves images faster than Apple's encoder." That's a cool feat and is a little damning for Accelerate.framework, although the way techcrunch writes it I expected a new kind of fast cosine transform.

Don't forget that SnappyCam pumps both CPU cores when available. The actual DCT algorithm created and used in the app is different to the typical AAN (Arai, Agui, Nakajima) DCT algorithm that's used in JPEG codecs, at least all the ones I've seen. It's all about doing as little work as possible to achieve the end result. That's why there's so much asm implementation, with carefully chosen NEON instructions for each s…

One of my colleagues at work (Bart Smaalders) is known for the saying (paraphrasing?): "The easiest way to go faster is to do less work."

Well done on realising something that seems obvious in retrospect, but most people still miss.

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

#107

Post by jpap »

gandalfu wrote: post #87
jpap wrote: post #79

Earlier quoted context omitted.

haha, yes, if only it pays to be lazy. :) Sometimes doing "less work" means more up-front planning and thinking. Not a bad thing necessarily. Interesting on the native camera adjustment. SnappyCam will use the "low light boost" high ISO capabilities of the camera. I'll have a play around with it. Otherwise, does the continuous flash help you much?

The continuous flash didn't fire. I'm running the stock settings.

Oh, it's a manual flash.

Enabling that automatically is an interesting problem in itself: I'd have to estimate the light level based on the camera preview... or perhaps from the preview metadata.

Will think about how that might be done. Thanks for the thought. :-)

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

#108

Post by Myrth »

jpap wrote: post #98
wingspan wrote: post #94

Earlier quoted context omitted.

It also doesn't work for me in Chrome on Win8. It does work in IE10, though.

It shudders me to think that IE won over Chrome. :( I saw an issue also reported on here earlier today a few days ago. Sounds to me like a (new) canvas bug in Chrome. There are unfortunately several workarounds for browser bugs in the HTML5 viewer. The AS3 Flash port was surprisingly very solid. I can't wait to share more info on that when it's time for another major release.

Chrome 28 on Win8 here - works great, thank you for making it! Even though I personally can't use it since I'm on Android.

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

#109

Post by jpap »

dschleef wrote: post #102

This kind of functionality is standard on OMAP4 devices.

ARM actually publishes reference code under the library name "OpenMAX" for their mobile processors.

I've read ARM's source code and found they they too use the AAN algorithm for the DCT. (They provide a tonne of code for other multimedia related stuff too.)

I learned a lot from their code, even though my implementation is completely different and original.

I would also dare to say that my asm source is maintainable. I had a very hard time understanding their code as it wasn't very well documented or laid out... but nevertheless a valuable learning tool.

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

#110

Post by Myrth »

> To put the speed in perspective, SnappyCam is about 4X faster than the normal iPhone 5 Camera app, and more than twice as quick as the Samsung Galaxy S4′s 7.5 shots per second.

Does it mean that S4's hardware is faster than iPhone 5 given they're using similar algorithms, and if you'd make the same app for Android it could get even better results?

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