In part 1 of this blog series I had Microsoft’s Computer Vision analyze my avatar. Today I would like to ask Mr. Watson from IBM to do the same.

Setup

Same as last time, modern JavaScript and a modern browser.

Getting started with Watson APIs takes a few more steps but it’s still very intuitive. Once you’re all set with Bluemix account, you can provision the service you need and let it see your images.

API

IBM had two vision APIs. AlchemyVision has been recently merged with the Visual Recognition. If you use the original Alchemy endpoint, you will receive the following notice in the JSON response: THIS API FUNCTIONALITY IS DEPRECATED AND HAS BEEN MIGRATED TO WATSON VISUAL RECOGNITION. THIS API WILL BE DISABLED ON MAY 19, 2017.

The new unified API is a little weird. Similar to the computer vision from Microsoft, it can process binary images or can go after an image by its URL. Both need to be submitted as multipart/form-data though. Here’s an exampel from the API reference:

It’s the first HTTP API that I’ve seen where I would be asked to supply JSON parameters as a file upload. You guys? Anyway. Thanks to the Blob object I can emulate multipart file upload directly from JavaScript.

Another puzzling bit is the version parameter. There’s a v3 in the URL but you also need to supply a release date of the version of the API you want to use. Trying without it gives me 400 Bad Request. There’s no version on the service instance that I provisioned so I just rolled with what’s in the API reference. It worked.

I also couldn’t use fetch with this endpoint. This time it’s not on Watson though. My browser would happily send Accept-Encoding with gzip in it and IBM’s nginx would gladly zip up the response. Chrome dev tools can deal with it but fetch apparently can’t. I get SyntaxError: Unexpected end of input at SyntaxError (native) when calling .json() on the response object.

Not sending Accept-Encoding would help but it’s one of the headers you can’t set. I had to resort to good old XHR.

And Here We Go

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// my avatar
const image = 'http://media.licdn.com/mpr/mpr/shrinknp_400_400/p/7/000/22b/22b/32f088c.jpg';

const key = '<use-your-own-key>';
const url = `http://gateway-a.watsonplatform.net/visual-recognition/api/v3/classify?api_key=${key}&version=2016-05-20`;

const parameters = JSON.stringify({
    'url': image,
    'classifier_ids': ['default'],
    'owners': ['IBM'],
    'threshold': 0.2
});

const data = new FormData();
data.append('parameters', new Blob([parameters], {'type': 'application/json'}));

const request = new XMLHttpRequest();

request.onload = function () {
    const data = JSON.parse(request.response);
    const tags = data.images[0].classifiers[0].classes;

    const describe = (tag) => `${tag.class}, ${Math.round(tag.score*100)}%`;

    console.log(tags.map(describe));
};

request.open('POST', url, true);
request.send(data);

The response from Watson?

Person, 100%

Yep. That’s it. That’s all the built-in classifier could tell me. You can train your own classifier(s) but they all appear to be basic. No feature detection that would allow to describe images. I tried to see all classes in the default classifier but the discovery endpoint returns 404 for default. I guess I will have to check back later ;)

I have more computer vision APIs to try. Stay tuned!

I’ve been actively looking at machine learning lately. Fascinating applications in day to day live! Often unexpected. Always amazing. More and more accessible every day. Google’s Motion Stills blew me away the other day. Classification of motion vectors and biased estimation models (in a temporal consistent manner, no less) - a lot of science and novel ideas in a free consumer mobile app. Enabled and powered by machine learning.

You have probably noticed a new breed of APIs popping up all over the web. Some simply call it Machine Learning APIs, others call it Cognitive Services, some simply call it Watson. Pre-trained models operationalized with an API layer and APIs to train your own.

This blog post series offers you a short tour of these new machine learning powered APIs. I am going to start with Vision and today I am tasting Microsoft Cogntive Services (aka Project Oxford).

Setup

I am going to use JavaScript and my browser. These are all HTTP APIs so I should be able to just talk to them with very little overhead or ceremonies. Besides, since the intent is to taste (and test) the APIs, I figured I would also take the latest JavaScript and browser APIs for a spin. No transpilation. No polyfills. No external dependencies. Hence a fair warning: the examples are likely to only work in latest evergreen browsers. I am using connect serve-static as my web server (here’s how).

Let’s see how much a computer vision can see in my avatar.

Describe

According to the documentation, the Describe endpoint generates a description of an image in human readable language with complete sentences. The description is based on a collection of content tags, which are also returned by the operation.

Getting started is just a few clicks and API reference is very transparent. Here we go:

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const explain = function(what, confidence) {
    return `${what} with ${Math.round(confidence*100)}% confidence`;    
};

// my avatar
const image = 'http://media.licdn.com/mpr/mpr/shrinknp_400_400/p/7/000/22b/22b/32f088c.jpg';

// Microsoft: Describe
const url = 'https://api.projectoxford.ai/vision/v1.0/describe?maxCandidates=3';
const key = '<use-your-own-key> ';

fetch(url, {
    method: 'POST',
    headers: new Headers({
        'Content-Type': 'application/json',
        'Ocp-Apim-Subscription-Key': key
    }),
    body: JSON.stringify({
        'url': image
    })
}).then(function(response) {
    return response.json();
}).then(function({description: {captions, tags}}) {
    console.log(captions.map((c) => explain(c.text, c.confidence)));
    console.log(tags);
});

Very straightforward with no surprises. Everything just worked. Here’s what the Describe API sees in my avatar:

A man holding a cell phone (19% confidence)
A man holding a phone (17% confidence)
A young man holding a cell phone (12% confidence)

It definitely sees a man. It’s not sure whether a man is young. It probably doesn’t know what a microphone is but it vaguely remembers that phones used to look like this:

Here are all the tags:

["person", "man", "indoor", "holding", "looking", "cellphone", "hand", "phone", "young", "laptop", "sitting", "standing", "table", "boy", "computer", "shirt", "using", "brush", "red", "blue", "people"]

Tags

Another API endpoint can report tags and also provide the level of confidence in each. I sent the same request to /vision/v1.0/tag and here’s what I got back:

person (100%)
man (95%)
indoor (94%)
microphone (22%)

I wonder why microphone wasn’t detected by the Describe endpoint. I would expect that Describe gets the tags from Tag and then uses language generation algorytms to build the description. Apparently not.

Analyze

One more API endpoint that can process an image from many angles at once. It will report the most likely description and will send down the tags. You can also ask it to detect faces and more. I asked for Description, Tags, and Categories. This one does feel like an aggregation. I got the same set of tags as I got from Tags, same most likely description (with a cell phone) and a longer list of tags as I got from Describe. The category was identified as:

people_young with 81% confidence

Summary

Microsoft Vision API allows you to see one image at a time. You can either upload the binary or point it at a publicly accessible URL. Depending on what you’re after you can get different results. I am still puzzled by the difference in reported tags. It’s capable of working with domain models to do more specialized detection but right now has only one trained - celebrities. I am sure Microsoft will deploy more and will likely let you train your own. I don’t know when but I know that there are other vision APIs that do so.

Next time I will talk to Mr. Watson. Stay tuned!