Machine Learning is quite a buzzword these days and we have witnessed how quickly Microsoft and other vendors have made progress in this area. Just couple of years back Microsoft had no product or tool in this space and today they have closer to a dozen. Recently Microsoft has integrated Machine Learning into SQL Server and Dynamics CRM, it is slowly becoming core to its product line.
I would not be surprised if machine learning becomes a mandatory skill for most of the development jobs in the next decade.
How Image Recognition can help CRM?
Attaching documents is a common feature asked for in many CRM projects where customers can complete an application form and then upload scanned copies to support their application. Think of invoices, receipts, certificates, licenses, etc. As of now there is no way that Dynamics CRM can detect if the scan that a customer is uploading is a picture of a license, or beach or a car.
What if Dynamics CRM can detect and recognise the scanned image and tell the user that it is expecting a license not a Dilbert on the beach.
Source: Ol.v!er [H2vPk] – Flickr
Wouldn’t it be great?
Although there are some Image engines that can tell you what an uploaded picture contains but there isn’t any engine or tool (as per my knowledge) that can tell whether an upload document is a license or not. This is because there are only subtle differences between scanned copies of various documents.
In this blog series I will build and demonstrate an approach to have this kind of image recognition capability with our favourite Dynamics CRM and we will use a branch of machine learning called Deep Learning that is very good at tasks related to Computer Vision. I would not be delving into the concepts of Deep Learning (there are numerous posts and videos on the internet) but will try to cover the major building block in this whirlwind tour.
Australian Identity Documents
I will take a real business case which is ubiquitous in many online applications in Australia where a customer is asked to provide a scan of their Australian ID as a proof. For our blog we will use the following Australian IDs
|1) Victoria Driver’s License||
|2) Australian Visa||
|3) Medicare card||
Note: Because of their sensitive nature I would only be exposing sample documents in this blog
The expectation is that the system can tell if the user is attaching a scanned copy of their Australian Visa when the record type is Australian Visa. So we will validate the image based on its content.
Good thing about deep learning based systems is that the detection algorithms do not rely on exact colour, resolution and placement but rather on pattern and feature matching. I got pretty good results when I built this system which I will share in later posts.
Deep Learning based systems use a concept of neural networks to train themselves and to perform their tasks. There are many kinds of neural networks and the one that does the job for us is the Convolutional Neural Network. CNNs are good at image related tasks.
In order to train a CNN from scratch you need lot of hardware and computing power and I do not have that. So I will be using a partially trained network and customise it for our specific task i.e. to identify the images of those 3 types of Australian IDs.
Let us cover the building blocks of our solution
TensorFlow is an open source framework for Deep Learning and we will be using it to train our engine.
TensorFlow comes in many platforms but we will use its Python version.
Once our model is trained we will deploy it online as web service and CRM can query that. I would not be posting the integration code here as I have already posted code to integrate Dynamics CRM with Machine Learning web services in my other blog
Let us start by training an image recognition model that can classify an image e.g. a scanned copy and tell if it is an Australian ID e.g. driving license or visa scan, etc.
We will use an approach called Transfer Learning. In this approach you take an existing Convolutional Neural Network and retrain its last few layers. Think of it this way that you have already got a network that can detect differences of aeroplane from a dog but you need to retrain it to pick more subtle differences i.e. the difference between a scanned invoice and a scanned passport.
TensorFlow is based on the concept of a tensor which is a mathematical vector that contains the features of an image. We will grab the penultimate layer of tensors and retrain it with some sample images of a Medicare card, an Australian Visa and Victoria’s Driver license.
Once the model is trained we will use a simple Support Vector Machine classify and predict the likelihood of the uploaded image to be an Australian ID. The output of the SVC classifier will a predicted class along with a likelihood probability e.g.
|(Visa, 0.83)||Model thinks 83% the image is that of an Australian Visa|
|(Medicare, 0.89)||89%, it is a Medicare|
|(License, 0.45)||45% it is a license|
If the confidence percentage is low it means that image is not in the class of our interest e.g. in the last example the uploaded image is most likely not a license. As a rule of thumb, a probability of 0.80 is good mark for the prediction to be reliable.
Below are the screenshots of the samples that I used as a training for my image classification model. As you can see images differ in terms of angles, positioning, colours, etc. system can still learn based on important properties and disregard irrelevant properties.
|Victoria Driver’s License
The training procedure involves categorising all the training images into a folder which is a named after their class. As you can see in the screenshots above, the windows folders are named after the class i.e. DriversLicense, Medicare and Visa
We then iterate over all these images and pass them to the penultimate layer of TensorFlow which gives us a feature tensor (a 2048 dimensional array of that image), we then label the image with its respective class.
Support Vector Machine
Once we have the feature tensor and label of every image, our training dataset is complete and we feed it to a Support Vector Machine and train the model. To save time, I pickled the model so that it can be reused for all predictions.
I know some of this terminology may be new to you but in the next post I will explain the architecture and some sample code that generates the predictions. Then it will start falling in place. See you then.
In the previous two instalments I have been explaining the image recognition system that I built to recognise Australian IDs and discussed how our traditional CRM can benefit from such intelligent capabilities.
In this post I will cover the Architecture and share some sample code
As you can see above there are basically two major pillars of the system
B) CRM ecosystem
Python is used to build the model using TensorFlow, then the compiled version of the trained model is deployed to an online webservice that should be able to accept binary contents like image data.
On the CRM ecosystem side, user can upload the image in a web portal or directly from CRM based on the scenario, then we need to pass it to the model and get the score.
Below is an excerpt of the source code from one of the unit tests that will give you glimpse of what happens under the hood on Python side of the fence. This is just one class for introductory purposes, not the entire source code.
The purpose of the above stub is to test the prediction class ClassifyAustralianID with a sample image L5.jpg which is below. As we can see it is a driving license.
Running this image against the model gives us this output
It means the model says, it is 93% sure that the input image matches the Driving License class. In my testing I found anything above 80% was the correct prediction
i.e. the confidence percentage for the below images was low because they do not belong to one of our classes (Drivers License, Visa or Medicare), which is the expected output
Image recognition is a field of budding research and getting a lot of attention these days because of driverless cars, robots, etc. This little proof of concept gave me a lot of insight into how things work behind the scenes and it was a great experience to create such a smart system. The world of machine learning is very interesting!!
Hope you enjoyed the blog.