[Google Cloud Vision OCR] .Net assembly to use ocr functions
Forge component by Aurelio Junior
Published on 04 Apr 2019


I have tested your tools online and it satisfies my needed. I will explain my scenario.
I have a lot of images (pictures) and they contains some texts i need to extract and save it on a database..

Your tools is exactly what i need, because it extract the real text that recognize and associate the info to these images..

Is there an externall .dll file that may i use in my development environment (i can use Windev 22 or Visual Studio 2017).

In case you want to reply me by e-mail : gmspano@<remove>tiscali.it

Thanks in advance

Rank: #118

Hi Gianni,

You can download the extension, open it in Integration Studio and then select "Edit Source Code" to open the project in Visual Studio. From there, you can use the whole project as it is or extract only the code that interests you.

Rank: #61385

Hello Aurelio

I have installed Integration Studio and downloaded the GooglecloudVisionOCR.oap file.
How to load the .oap file?? Is this the extension file?

Please, let me know how to proceed because i'm new user with Integration Studio and i only need to extract the function that allow me to read texts from images as your program does.

Please, can you help me?
Thanks in advance


p.s In case you want to send me some stuff, use my email : gmspano at tiscali dot it.

I don't think Google Cloud Vision OCR component have .NET assembly in it.

Google Cloud Vision OCR is accessible using REST API, and I think that component use REST API instead of .NET assembly.

Google "Cloud" by definition is not something that done in client side (.NET assembly), instead it is done in cloud (aka Google server).

You need to pay for such service, and all works is done in Google owned server.

There is no .NET assembly that can make Google Cloud Vision OCR works on your own server.

Rank: #118

Hi Gianni,

Sorry, I assumed you were already familiar with OutSystems.

You can open the .oap file with any file compactor (I use 7zip). Inside it, there's a file called GoogleCloudVisionOCR.xif, which is the actual extension file that you need. Extract it and open it in Integration Studio. If you get a prompt to connect to an OutSystems environment, just discard it. Then click on the button highlighted bellow:

You'll probably get a message asking you to define Integration Studio options. Select Yes and, in the ".NET" tab, fill in the path to Visual Studio in your machine (the devenv.exe executable). You should now be able to open the project in Visual Studio.

Let me know if you need any further help.

@Harlin: you're partially right. Google Cloud Vision is indeed a REST API. However, the extension I built uses Google's .NET assembly which allows you to easily call the API from .NET applications. Also, the extension itself is a .NET assembly. So you have two .NET assemblies between your OutSystems application and Google's REST API.

Rank: #61385

Hello Aurelio

Thank your for your reply.

I have been able to load the project and see the source code.
it is a bit too hard to me!! i'm not a c# developer despite i can "read" the statements.

As i told you i need to load a lot of postal cards with images in front and some informations about the location of the pictures on its back. These stuff come from a customer. I'm developing an application to use on an Android tabled and create a sort of catalog.
These informations must be loaded and saved in a database.
I did a little test using your online tool and it seem to satisfy my needed.
Please, is it possible to create a library to include in my Windev environment (i can use .net assemblies) and pass to it two parameters: pathname of the picture and a array of string that contains the information read from the back of the postal card?? (like, city, location, code..a max of 10 elements) or a txt file autocreate using the same image name?
Or if it is possible to create an executable always passing the pathname and create a txt file using the same image's name with a ".txt" extension with the information as above.

Thanks in advance.


Rank: #1271


I have a question: May I use this for get data from PDF file? If answer is yes, how? ; else : any recommendation?

Best Regards 

Rank: #118

Hi Edgardo,

Not in its current state. I think Google's Cloud Vision does have functionality to read text from pdf files, but I'd have to incorporate the functionality into the extension, and finding time to work on this has been very difficult :).

Hi Aurelio,
I need to implement Google cloud vision OCRon mobile platform. But when I opened the .NET code, I found these errors. I have posted several times but still didn't fix. Please help to fix.

*attached a screenshot.


Rank: #118

Hi Tanijn,

Did you change the project's references? Make sure you have this reference:

Rank: #118

That might be the reason why you're having issues with the references. Try opening the project by clicking this button in Integration Studio:

If you get the message saying that the options are not correctly defined, go to Edit/Options and enter the .NET options as below. Be aware that the paths might be different for you, depending on where you installed Visual Studio.

Hi Aurelio,

That worked. Thank you so much.

I have another query, how and where will I apply the API key in the .Net code? I couldn't trace that. Actually, I am new in Outsystems. I have the API key from GCS. I have to implement an OCR for my application.