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Show HN: API for detecting people, cars, and everyday objects in images

dextrorobotics.com

21–30 of 74 posts

Re: Show HN: API for detecting people, cars, and everyday objects in images

#21

Tried detecting Airplanes on this image with 18 airplanes, but it only detected 4 of them. https://lh3.ggpht.com/-GbPgbhUtmnE/UH0p3VmMWoI/AAAAAAAAApM/u...

The browser demo page says "Dextro supports up to 4 objects to be detected concurrently when used via the full API.", I think that's the problem.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#22
post #10

As a long time CV enthusiast, I applaude the tech and the way you guys make it "just work". However for any serious application I feel a few things are missing: - your pricing won't work for video (even at only 5fps) - I can't really use the data without a confidence level of detection. Because for some applications I'd rather discard a bouding box that is below a threshold I set. Other than that, congrats for the gr…

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.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#23

Failed completely for me across a half dozen tries. I wonder how cheaply you could get results via Mechanical Turk. I bet you could get much more accurate results for a very low price but with some added latency.

One to two cents a task. Anytime you have a language agnostic task (identifying/classifying objects, etc), the tasks can be done very cheaply. Just make sure you do triplicate validation.

Language dependent/creative tasks run much higher (smaller worker pool, more brain power needed).

Re: Show HN: API for detecting people, cars, and everyday objects in images

#24
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.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#25
post #21

Tried detecting Airplanes on this image with 18 airplanes, but it only detected 4 of them. https://lh3.ggpht.com/-GbPgbhUtmnE/UH0p3VmMWoI/AAAAAAAAApM/u...

The browser demo page says "Dextro supports up to 4 objects to be detected concurrently when used via the full API.", I think that's the problem.

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.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#26
post #3

Did a few tests and it works pretty well! No false positives at least. Any plans to increase the number of objects you can search for at once? Very interested in using this but I'd want to be able to scan for ~20 objects.

Yes! Scanning for more than 4 objects at once (which is currently supported) is something that we definitely want to enable in the future. The only constraint is the number of GPU machines we can afford.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#27
I have been tinkering with a similar side project which you can read about here:

http://artificial-intelligence-projects.com/augmented-realit...

It's still in the development stage because I can only fiddle with it when I have the time and impetus to do so. Criticisms/comments welcome.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#28
This reminds me of how my visual psychology professor was attempting to help those with poor vision 15 years ago, but didn't appear to get anywhere with at the time.

The idea was a simple (but clever) one - use virtual reality to segment the world into solid blocks of identified objects. The solid blocks are identifiable to those with poor vision in a way that the real world is not.

Essentially this meant processing an image, identifying items e.g. cars, fences, roads etc and then colouring them solid. So instead of a confusing scene of blur, you have a blurred but still identifiable scene of a solid strip of grey for the road, a solid blob of red for the car, another solid yellow stip for a fence etc. A poorly sighted person could still identify from this something that made sense in a way that they couldn't in the real world.

What was required was an input, real time visual processing and then display back to the user - all of which was fantasy 15 year ago.

However, attempt this today with a visual feed, real time processing like this, and then near instantaneous display of the results back to the person with e.g. google glass, and you might have a viable way to show the world categorised in a visual way that will help those with poor vision. Interesting times.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#29
post #23

Failed completely for me across a half dozen tries. I wonder how cheaply you could get results via Mechanical Turk. I bet you could get much more accurate results for a very low price but with some added latency.

One to two cents a task. Anytime you have a language agnostic task (identifying/classifying objects, etc), the tasks can be done very cheaply. Just make sure you do triplicate validation. Language dependent/creative tasks run much higher (smaller worker pool, more brain power needed).

I've never used mechanical turk before and don't understand what you mean by language agnostic. I'd want someone to tell me that it's a "car" and not a 汽車. And I'd want to give the instructions for the task in English.

Re: Show HN: API for detecting people, cars, and everyday objects in images

#30
Wow, I just tried this image of faces:

http://3rdarm.biz/images/2010/02/faces.jpg

It got almost all of them but so many errors. It can't detect sheeps either.

I was really impressed at first, but as I tried out more and more images, it became apparent that the api isn't mature enough for one or two cents worth of money. There is a 90% of the algorithm detect the image correctly, but sometimes it doesn't detect the entire object. For example, I used another image of two jets, but it only found one of them even though the jets were identical, but one was smaller than the other.

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