Multithreaded Filtering
To ensure multithreaded filter processes are thread-safe, you must create a unique Filter context for every thread by instantiating a Filter object. In addition, threads must not share context objects, and the same context object must be used for all API calls in the same thread. Creating a context object for every thread does not affect performance because the context object uses minimal resources.
For example, your code should have the following logic in a thread:
Filter objFilter = new Filter("YOUR_KEYVIEW_LICENSE");
objFilter.FilterDirectory = m_filterDirectory;
objFilter.SetInputSource(infile);
objFilter.GetDocFormatInfo();
if (objFilter.CanFilter() == true)
objFilter.FilterTo(outfile);
objFilter.ShutdownFilter();