Optimal Techniques for Server Based Image Processing

When it comes to server-based image processing, businesses have options that can help accelerate data retrieval and cut down on processing time. ECM system approaches today concentrate the storage and indexing of data on the server and leave viewing, editing and annotation to be done on the client using a variety of document viewers. This has been the traditional approach for ECM vendors because they hand off the task of installing and maintaining the document viewer to the client.

The problem with this approach is that it requires the installation of software on multiple boxes. This is time consuming and expensive and it incurs ongoing costs, as it will be necessary to provide ongoing maintenance for each client.  Maintaining individual clients can be further complicated by other programs which users have installed; the IT department doesn’t necessarily know which applications exist on each individual client.  

As customers look for greater ease of use and faster performance, newer systems are now adding enhancements like page extraction on the server. This feature eliminates the downloads of large documents to the client and enhances overall system security by restricting the data that needs to be downloaded.  Additionally, by rendering all documents to one common format, clients can operate using one universal viewer rather than a multitude of them.

Traditionally an ECM system pulls a large document from the repository and then downloads it in its entirety to the client, where viewing or processing will occur.  This approach incurs multiple performance and cost penalties:

  • Large documents require lengthy downloads.
  • The user will need to pre-install and maintain a viewing application or download an ActiveX component, or download an applet, before the document is brought down. 
  • A powerful client viewer is required to display and annotate the larger and more complex document downloads. 
  • Companies risk a loss of security as entire documents are downloaded over the web and then stored on a client that may not be secure.

Today the most modern vendors promote limiting downloads to single pages.  This is done by extracting pages or images from within multipage documents on the server.  One big advantage of this approach is expedited performance: Users will only need to download the page(s) they need and the server can support multiple users on a client system simultaneously. The server also provides more memory and a powerful processor making it a more reliable viewing and processing option then multiple individual clients. It is also easier to maintain a single server. 

There are some additional efficiency considerations that a well-designed product can offer.  When large documents are decompressed to be manipulated, they require large buffers for the data.  In the past, defining and creating the properly-sized buffer was a hit or miss affair because differing document types require different buffer sizes.  New technology can determine the correct buffer size automatically, thereby conserving memory for other server processes and making operation smoother and more efficient. With this capability, the system no longer needs to allocate excessive amounts of memory or write routines to calculate the amounts needed.

Some new systems allow document rendering to occur completely in memory, eliminating the need to save and retrieve from disk.  One obvious benefit of complete memory operation is the accelerated rendering and extraction speed.  Additionally, because memory permits access by multiple processes simultaneously (rendering, processing and converting),  these features can serve multiple users simultaneously. One server can support multiple CPUs and multiple processes, while a disk can only be accessed by one process at a time.

Businesses that are looking to expedite image retrieval and processing  should consider the benefits of server-based rendering and/or page extraction performed all in memory. These capabilities can be built into content management systems easily, by utilizing a client/server viewer or a quality imaging SDK, adding value to the system and streamlining overall document workflow.