Saturday, 8 June 2013

Image Capture Component for Web Applications


I am working on a project, which requires acquiring images from scanners in a web browser. I am curious to know if HTML5 / CSS3 in any way help accomplishing this feature or if there are any javascript libraries out there so that the implementation can work across all browsers. Or else, you may suggest various other options available for me to meet this need.

By: Anonymous


The HTML5 and CSS3 specifications are all about presentation and thus will be able to detect output devices like print, tv, handheld devices, etc, but there isn't any support for input devices like image scanner or camera. Interacting with such devices can however be achieved using javascript and browser specific ActiveX, Browser Plugin or an Applet. There are many third party libraries with varying capabilities and support for a multitude of programming languages, which can be wrapped within an appropriate component and then use Javascript to interact with it.

I have personally used the EZTwain Library for the windows platform by building a Visual Basic based ActiveX component earlier on and later using VB.NET based library and used it within IE successfully. This library however has support for very many programming languages including C++ and Java. Its usage can be extended across various other browsers by wrapping it within an appropriate component. EZ Twain seems to be reasonably priced and comes with royalty free runtime distribution.

If you are a hardcore programmer, this Code Project Article is worth a look, where the author demonstrates building a C++ wrapper using the TWAIN_32.DLL which used to be distributed by Microsoft in earlier versions of Windows. In later versions of Windows (Windows XP SP1 and later), Microsoft has Windows Image Acquisition Automation Layer, which is worth exploring.

ByteScout Scan SDK is another free (FreeBSD License) library for .NET based applications which can also be explored for its extensibility into other environments. Dynamsoft has an image capture suite with pre-built and ready to consume components for various browsers, but carries a hefty price tag though.

The following are few other Tool kits that are worth exploring.

LeadTools Twain SDK
Acusoft's ImageGear for .NET
Victor Image Processing Library

Almost all of the solutions above are targeted at Windows platform. If you are expecting your solution to work on Non windows platform, you should look for similar libraries and build similar wrapper components for the target browser / platform combination.