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Groupdocs Signature App Queries

Dear Sales,

We are evaluating various software/components for our Invoicing/procurement application being developed in C# .net core. Groupdocs Signature App is promising and we are evaluating it and need some clarification.

Groupdocs Signature App Queries…

Upload an image
Can we flatten the images so that when converted back to word etc they are not editable separately.

Draw image
a. Using mouse
b. type (Using various fonts)?
Protect with Digital Certificate
a. Can we use Digital certificates installed on local machine
b. Can we use certificate stored and HSM devices hosted in cloud by AWS, Microsoft etc
QR code
Can we replace your code and access our QR code hosted on our server.

Hi, @netgains

Thank you for your interest in our product. Let me share few concepts that could help you to find the best approach for your solution.
GroupDocs Signature App is a free demo to show simple operations with the Signature library.
The back end/server side code uses our product GroupDocs Signature for .Net / Java
You may find some demo here

and additional examples here

All these examples could be found on GitHub here

So back to your question.

  1. Upload an image. Signature can add image to document to any page with specified settings (like location, size, page number, opacity, alignment on page, some extra effects like borders, shadows etc).
    Library does not provide parsing images to words but there’s ability to add Text Signatures to documents as images
    So you do not have to convert text /string to image library will do it automatically and this text can not be grabbed from document.

  2. Draw image on Front-end. There are Front-End and Back-end solution. You may use some demo hand written images and pass them to the server side to receive document with hand-written signature in it.

  3. Protecting with Digital Certificate.
    Signature uses pfx files as Digital Certificates. Pfx will is enough to digitally sign document (PDF / Words/Excel/Presentation). You may pass any pfx from any location. The only thing you have to implement on server side receving PFX data from AWS / KeyVault etc. Currently Signature does not support this feature due to various authentication implementation.

  4. QR Code.
    You may pass any QR code from various location,
    Library will generate barcode and QR-code of any supported type

See more examples how Signature allows to encrypt any data to your QR-code

For your .Net core Web App you can use on server side our library Signature for .Net

To implement some Front-end samples you also can use some implementation from here

Please share if I was able to clarify your questions and maybe you need more details from my side?

Thank you!

We are going through the sample codes and checking out the features. I am not sure if I was able to communicate my requirement properly so writing them again.

  1. Draw Signatures:
    Drawing signature is always a challenge using mouse. So why not give option to type name and signaure fonts like Electronic Signatures in a PDF | PSPDFKit ( › blog › electronic-signatures-on-pdf)

  2. Digital Signature
    User will not be comfortable uploading Digital Signature. How do we access Signatures stored on HSM device etc? is GroupDocs.Signature-for-.NET-MVC solution for it?

  3. QR code
    We have internal API which can generate beautiful QR codes with logos, background and colors. Is it possible to integrate the same in GroupDocs.Signature?



Hi, Rishikeshj

Thank you for further clarifications.

  1. The GroupDocs.Signature App Demo is an online demonstration of GroupDocs.Signature for .NET abilities and features. One of them is hand-made signature drawing as an example of your implementation. Near future we will provide the same functionality as you shared to enter text with special fonts to mimic the hand-written signature.

Besides that, the server side could be found below to do the same

There’s the ability to pass Text Signature and adjust it with additional options like Font, Size, Colors, Backgrounds, Effects etc.

So you may pass names like ‘John Smith’ with required Font etc to obtain Text Signature on the document. This signature can be generated as native text or like an image on a document page.

  1. Using Digital Certificates.

The server side library creates Digital Signatures for the documents using the PFX certificate files.
So the server-side part expects the PFX file/stream/bytes to be passed to the library (with the password of the private key).
At this moment the GroupDocs.Signature API product doesn’t support communication with exact devices due to a variety of SDK / specifications.
In your case the approach could be as follows.

  • your server side code / front-end code accesses the HSM device to obtain the certificate. Please be aware that a digital certificate should be with a private/public key - this is the only way for proper digital signing. Having this certificate (as Stream/ bytes buffer / file) you pass it to the Signature library.
  1. QR-Code.

Having generated QR-Code as an image (in any format) you can pass it to the GroupDocs.Signature product as an Image signature object.

Besides that, GroupDocs.Signature for .Net/Java also can generate any QR-code.

So it’s easy to integrate your QR code images to the GroupDocs.Signature App

Rishikeshj, trying to help you with our product,

it seems that the main misunderstanding between your questions and my answers is related to basic principles using the Signature products.

This Demo contains Server Side (Back-end BE) that serves REST API communication with the Front-End UI part.

Server part implements low level document processing. Like adding signatures of various types to the document based on the passed options from Front-End UI.

So, the GroupDocs.Signature for .NET is a server side library that accepts document and signature options and returns output document (stream/file).

As an alternative solution we have GroupDocs Signature for Cloud - this is a REST-full API that can serve your Front-End application.

So summarize your questions, App is a demonstration of Signature for .NET/Java abilities.

There are following parts that will help you to build your solutions

  1. GroupDocs.Signature for .NET/Java - server side solutions

  2. GroupDocs Signature Cloud - document eSign REST API based solution

  3. GroupDocs Signature Free App, front-end samples like GroupDocs.Signature for MVC - are demonstrations of how to use solutions from points 1 and 2.