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jluan

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Hey guys, I'm David, one of the founders of Dextro. Happy to answer any questions about how we got this to work technically!

At a high level, here's how we did it: 1) We're using the Twitter Streaming API to find every publicly accessible live-stream. 2) We extract the live stream using a version of PhantomJS that still supports Flash. 3) Each live stream is being sent to Dextro's livestream API endpoint, which streams back chunked JSON of what's happening in the stream in real time. (Check out some low level outputs at http://b.fastcompany.net/multisite_files/fastcompany/imageca...) 4) The results are aggregated and sent on a pub/sub socket to each client.

A background task crunches the live data into the "most viewed" and "most streamed" aggregate stats.

/======================================

Dextro - Senior Distributed Systems Engineer (NYC full-time)

=======================================/

// What we do

Dextro is a venture-backed AI-as-a-service company building an API that makes it easy for developers to search, filter, and gather actionable statistics over photo and video datasets — without knowing any computer vision or machine learning. Our technology powers the next generation of vision-enabled apps, robots, smart devices, and data analytics tools.

// Who we are

We are a small, highly technical team of vision engineers and researchers from the UPenn GRASP Lab, IIT Delhi, Microsoft, and iRobot. Python, CUDA, C++, and Ruby are our core languages. We have 10^~14 FLOPS of compute on-site regularly being maxed out by experiments and performance testing.

// Who you are

This is primarily a distributed systems and web services developer role but you will have computer vision responsibilities. Though we expect significant backend dev experience, you will learn the vision that you need on the job.

// More information

Check out more info at dextro.co/jobs and shoot us an email at jobs [] dextro.co if you're interested.

Yes! General tagging of videos with all possible tags is great for media discovery, but we've built our system with data analysis in mind. We want to be useful for those who want to analyze photo and video datasets when they already know what their query is.

We've found that most of the value is in the latter. For example, our system helps answer:

  1) on a publisher video server, which videos were about automotive?
     Can we package those ads off to car brands?
  2) how many people took photos of my brand's product on instagram
     after our marketing campaign?
  3) what were pedestrian traffic patterns like outside 
     our store based on the CCTV system?

/======================================

Dextro - Senior Backend Engineer (NYC full-time)

=======================================/

// What we do

Dextro is a venture-backed AI-as-a-service company building an API that recognizes brands, objects, and scenes in photos, videos, and live streams. Our technology powers the next generation of vision-enabled apps, robots, smart devices, and data analytics tools.

// Who we are

We are a small, highly technical team of vision engineers and researchers from the UPenn GRASP Lab, IIT Delhi, Microsoft, and iRobot. Python, CUDA, C++, and Ruby are our core languages. We have 10^~14 FLOPS of compute on-site regularly being maxed out by experiments and performance testing.

// Who you are

This is primarily a distributed systems and web services developer role but you will have computer vision responsibilities. Though we expect significant backend dev experience, you will learn the vision that you need on the job.

// More information

Check out more info at dextro.co/jobs and shoot me an email at jobs [] dextro.co if you're interested!

Dextro - Backend Engineering (NYC full-time)

===========================

Dextro is a venture-backed AI-as-a-service company building an API that recognizes brands, objects, and scenes in photos, videos, and live streams. Our technology powers the next generation of vision-enabled apps, robots, smart devices, and data analytics tools.

We are a small, highly technical team of vision engineers and researchers from the UPenn GRASP Lab, IIT Delhi, Microsoft, and iRobot. Python, CUDA, C++, and Ruby are our core languages. We have 10^~14 FLOPS of compute on-site regularly being maxed out by experiments and performance testing.

This is primarily a distributed systems and web services developer role but you will have computer vision responsibilities. Though we expect significant backend dev experience, you will learn the vision that you need on the job.

We would be open to H1B visa and/or remote for the very best candidates.

Check out more info at dextro.co/jobs and shoot me an email at jobs [] dextro.co if you're interested!

Dextro

Backend Web Engineer Intern

www.dextrorobotics.com

Dextro is seeking summer interns to join our small team of computer vision engineers from iRobot, Microsoft, UPenn GRASP Lab, and Yale. Dextro, founded in 2011, is a cloud service that recognizes objects in photos and videos with the goal of turning a picture into its thousand words. We have several enterprise partnerships and work with hundreds of makers and hackers; our only HN post spent a day as #1.

Requirements:

  * Interest in teaching mobile devices, robots, and webapps new tricks.
  * Interest in helping computers interface with the unstructured real world.
  * Desire to work with the whole gamut of technologies,
       and the desire to learn what you don’t know.
  * Hunger. Both for success, and for meals with the team.

  * Must be highly proficient with either Python or both Rails and Ruby.
       Must be willing to learn the other.
  * Must be comfortable working and scripting in a Linux command line environment.
  * Bonus: proficiency in JavaScript and frontend web design, or 
       skill and interest in designing high-performance backend cloud infrastructure.
If you’re good at backend web development and are also interested in vision, we’ll make sure you’ll get to learn on the job.

Logistics:

  * $5000
  * 12 weeks
  * Breakfast and lunch provided
Interested? Email David Luan at david.luan [[]] dextrorobotics.com

Hey tunnuz and limejuice, sorry to hear we only picked up on 4 of the planes. We've biased our service towards precision rather than recall; thus, we try to be wrong about detected objects as little of the time as possible at the expense of perhaps missing a few object instances.

I want to clarify: the 4 object concurrent detection refers to 4 classes of objects. On the Experiment page, you can only choose one class to detect on (whether that is person, bottles, cars, etc). However, by using the API, you can simultaneously search for cars, planes, people, and motorcycles, for example.

Hey everybody, OP here. Thanks for the great feedback! We're really happy that so many people have checked this out.

One thing that I want to mention: our service was built favoring Precision over Recall; we reasoned that we'd rather have a low number of false positives and make sure that when we do report a detection, that it actually is one. Thus, our service may occasionally miss instances.

I'm going to implement a button on the Experiment page that lets you flag a detection as something that we need to work on; we will use your feedback to improve the accuracy.

Hey steeve, thanks for the really kind feedback! We're aware of the video pricing issue, and it's something that we're thinking hard to come up with a solution to for makers and developers.

In the meantime, if you want to experiment with Dextro for video, shoot us an email at team@dextrorobotics.com and we will hook you up!

With regard to confidence level, that's something that we provide the enterprise-class service with; if this is a critical feature, we can potentially offer it to everyone as well.

I don't think the point you make contradicts Steve Blank's at all; to me, Blank's thesis is that startups in the Valley no longer choose to pursue truly disruptive technological innovation because our ecosystem now almost exclusively rewards areas such as social media, where you have to run as fast as you can just to stay where you are, to the detriment of "hard tech" such as biotech, robotics, and the semiconductors of old.

If I'm not mistaken, a decent chunk of expense for commercial airlines is in fees to have a gate and terminal area for their aircraft. Here, they will probably fly out of the general aviation section of airports, where they'll get charged a small ramp fee at most.

Is it just me or is it ironic that Apple almost exclusively sells glossy screens, but writes this:

Eye strain refers to ocular fatigue, eye discomfort and headaches associated from intensive use of the eyes. Common causes include:

glare on the computer screen

Find a big problem, identify a basis for its vector space, and build that basis.

My opinion is that all "small problems with simple solutions" that have become successful were actually cases of big problems masquerading as small ones.

To my cranky old self, the overbearing similarity between this product (aimed at productivity) and services like Twitter and Facebook (aimed at fun), combined with the overly cheery, flippant color scheme, make it difficult for me to take my work in &! seriously and actually get things done.

This is incredible in terms of helping push the technology envelope further, but I'm afraid it's just going to be used in the short term by Android handset OEMs as another selling point to tout in the spec wars. I wish that they would focus on the end-to-end user experience more, rather than putting their own brand of lipstick on Android and trying to win a pointless spec arms race.

I have to disagree on this one -- Yale's policy actually really sucks. I am currently taking time off, and was told that not only must I take course credits from an outside school to get readmitted from a personal withdrawal, but also have to go through an abridged re-application process. A lot of time commitments and question marks there.