Hi,
Am I right in thinking that Opus only supports older pspimage files at present? Most of mine were saved with PaintShop Pro XII, and while Opus can display thumbnails for them it just reports 'is invalid or not a recognized picture format' when I try and open them in the Viewer. Files saved with older versions of PaintShop open fine but as more and more of my files are being updated as I work on them, it's becoming a problem!
We could probably add support for it if the format is documented somewhere, or if a library exists for it, but after a quick search I could not find anything about pspimage, only about the older psp format.
Also, and alternatively, if the makers of PSP have provided a Preview Handler for viewing the images in Windows Explorer then that should also work in Opus.
It's an interesting question 
I've realised I should have been clearer: Opus' Viewer can display not only .psp files but also .pspimage files saved by older versions of PSP, so presumably there's at least some support for it. There doesn't seem to be a Preview Handler available.
.psp and .pspimage are different formats.
I think .pspimage files can be saved in a way which is compatible with the older format and older versions of PSP itself, which may be why some of them work.
You may be right. Having had a look inside a "PSP9-compatible" pspimage, it appears to have been saved as a v7 file rather than a v9 as I'd expect, and pspimage was introduced in v8. Presumably it's actually now a .psp file with an incorrect extension.
So far I haven't found anything other than PSP itself which can load pspimage files. I assume Opus is relying on the shell-extension for the thumbnailing?
I may be misremembering but I think that since Corel acquired PSP changes to the file format specification have not been documented. I believe we tried contacting Corel at one point to see if the specifications were available and apart from wanting us to pay for a support contract they were not at all interested in being helpful.
That sounds depressingly plausible 
Superficially the file-formats appear similar, but comparing a .psp and a .pspimage of the same data (a single raster layer) there's clearly been a change in the way the bitmap data is encoded.
Ok, I'm admitting defeat I shall just have to use PaintShop to open .pspimage files. Unfortunately Opus seems convinced that they are image-files and insists on trying to open them with the Viewer.
I have explicitly set the 'Open' action for the .pspimage filetype to use PaintShop, and I have removed .pspimage from the Images File Type Group, but to no avail. Can someone please tell me what I'm missing?
Try changing the .pspimage filetype's Left Double-Click event so that it runs PSP with {filepath$} as the argument.
(You want the Events tab when editing the filetype. Don't get lost looking in the Actions tab. The stuff on the Events tab is specific to Opus, and will override everything else within Opus.)
You could also turn off Preferences / File Operations / Double-click on Files / Use internal picture viewer for but that would affect lots of other things that you probably still want to open in the viewer.
Thanks - that did it. I'm still unclear why Opus continues to believe that a .pspimage file is an Image, though.
It's probably recognising the header at the start of the file as a .PSP image, then passing that to the viewer which will only later realise it cannot decode the full file because it's not really in .PSP format.
So there's no way to change the configuration, then - it's built-in?
Would it be worth changing the code to use the associated program as a fallback if the viewer can't handle a particular file? It would certainly be preferable to getting an error message