Viewer Plugins

Help & Support
1

  1. In Viewer > Plugins my understanding is that 'MultiView' is a catch all, so that if no other viewer is configured for, e.g., .pdf files the MultiView will view them. Is that right?

  2. In Viewer > Plugins the Plugin entitled "ActiveC + Preview + Web" has a subtitle which is suffixed ("catch all"). Does "catch all" mean that if no other viewer is configured for, e.g., .pdf files then the "ActiveX....." plugin will view them? In other words, is "ActiveX..." the first catch all, and then MultiView the catch all of last resort?

  3. If I 'configure' the "ActiveX...." viewer there are, amongst others, a list of "Preview Handlers" and two Generic ActiveX, one 32-bit and the other 64-bit. I understand the Preview Handlers, but:
    i) What are the Generic ActiveX items for?
    ii) Why is there one for 32 bit and 64 bit?
    iii) When I add the e.g. .pdf file extension to a preview handler, it removes it from whatever previous preview handler was handling pdfs. But how come I can assign a ..pdf to a 32 bit preview handler AND the Generic ActiveX 64-bit thing?
    iv) If I remove the .pdf extension from all of the preview handlers, and assign it to the Generic ActiveX 32-bit thing what should be previewing it?

2

  1. Yes, if the plugin is able to. MultiView requires some 3rd party viewer DLLs which don't come with Opus, but can be used if they are installed.

  2. Catch-all basically means the plugin handles a lot of file types, usually as a proxy for various third party viewers that weren't written specifically for Opus, and that it would not normally be the first choice if an Opus-specific viewer was available for the same format.

  3. A "Preview Handler is a newer, more refined type of ActiveX control specifically designed to be used in the preview panes of File Explorer, Microsoft Outlook, and similar programs, which Opus can also use via this plugin. "Generic ActiveX" components are a more general/basic thing which may be able to do something similar (but usually not in as good a way), or may do something completely different.

    Most Generic ActiveX controls that are useful for viewing files were written with the intention of being used within Internet Explorer. Some work better when actually hosted by Internet Explorer rather than something else, which is why there's also an option to view things with IE sandwiched between Opus and the control, acting as a proxy.

    In the plugin, Generic ActiveX depends entirely on the registry to provide a mapping from file types to the control to use. Whether it works for PDF depends on whether an ActiveX control in your system is registered to handle PDF (and also whether some other PDF software installed or updated later has messed up the registry settings; PDF software is notorious for messing up other PDF software's registry settings, and generally not being written carefully or with a mind to coexisting).

    Preview Handlers also get their default list of files from the registry, and can be messed up by other software, but the way the assignment is defined is better, and that allows us to show a list of viewers and types, and also let you edit that list if you want to move things around or correct missing extensions. Any changes made there are local to Opus and don't affect the registry or other things which use Preview Handlers. The aim is to let you override things without affecting other software, and also in a way which can be exported as part of your Opus config.

    In terms of Generic ActiveX vs Preview Handlers, Preview Handlers are usually best, if one is available for the format you have. That's not always true though; just a general rule.

Whatever you view PDF files with, you'll need to have a suitable PDF viewer installed. Most good, modern PDF viewers include a Preview Handler.

3

Thanks.

If anyone cares, I stumbled upon a way to manipulate PDFs directly in the Dopus viewer. Install Phantom Standard 32 bit, elect to install only the shell extensions (I also installed the ifilter but I think that's irrelevant). Within Dopus, within config of "ActiveX + Preview + Office...etc" check the Generic ActiveX 32-bit option, and add to it the .pdf file extension. View a pdf file, right click, uncheck 'read mode' and from there you can highlight, add text etc. You can also search text. The downside is i) I think you can only save copies, not an amended original ii) it's not the fastest pdf previewer i've used.

1 Like