GP SoftwareTwitter
Opus FAQsManualCommandsObjects

Problem with 1bit TIFFs in Viewer

I wasnt sure what to call these images - they are completely black/white - NOT greyscale; 1bit TIFF files.

The DOpus 10 viewer seems to just show a thumbnail. Other viewers including windows default viewer are able to display these images correctly.

I attach three files:

Note in the preview I can only see two files - I cant see the sample file- it looks like the forum has the same problem as the viewer :slight_smile:
I'll try just leaving the sample as an attachment

~ as it looks in windows default viewer @ 100%
~ as it looks in DOpus viewer (says 800% but that's 800% of the thumbnail I presume)
~ a cropped version of the file viewed



unfortunately the sample file doesnt even show as an attachment.
I tried adding it to imageshack but it converts it to png :confused:

It's not so much the forum as that no web browser can display TIFF images so when the forum puts it on the page the browser doesn't know what to do with it.

Zip it and attach the zip.

[quote="leo"]It's not so much the forum as that no web browser can display TIFF images so when the forum puts it on the page the browser doesn't know what to do with it.

Zip it and attach the zip.[/quote]

thanks Leo -
zipped & attached:
Ryland.zip (11.5 KB)

It turns out this is by-design.

The TIFF file has its resolution set to 600 DPI, and (presumably to deal with very high-res scanned faxes; it was requested many years ago although we're stuggling to remember exactly why) Opus scales 1-bit TIFF images to 72 DPI.

Re-saving the TIFF set to 72 DPI makes it view fine in Opus. (The filesize also increased, which I think is just Photoshop adding a load of metadata or not compressing the data as well. At least, it looks like the same pixels in Photoshop for both images so I don't think it's actually enlarged the image.)

file2.zip (18.5 KB)

[quote="leo"]It turns out this is by-design.

The TIFF file has its resolution set to 600 DPI, and (presumably to deal with very high-res scanned faxes; it was requested many years ago although we're stuggling to remember exactly why) Opus scales 1-bit TIFF images to 72 DPI.

Re-saving the TIFF set to 72 DPI makes it view fine in Opus. (The filesize also increased, which I think is just Photoshop adding a load of metadata or not compressing the data as well. At least, it looks like the same pixels in Photoshop for both images so I don't think it's actually enlarged the image.)[/quote]
Unfortunately changing the image resolution is not an option for me (I'd just have to change it back again after) - do you think is there any chance this 'fix' could be made optional ?
Or should I apply through official channels ?

I dont remember this being the case in Opus previously, but it is years since I worked with images like this. I'm just starting a job where I have to work with a lot of these hi-res tiff images (amongst various other filetypes) but I need a file manager - not an image management programme...

Is it possible this was requested cause the computers at the time couldn't cope with a full A4 page TIFF at hi-resolution ? That can be a problem with colour, or greyscale imagse, but it should not be a problem with 1 bit images (even with a not very new 'office' computer)

Or could it be related to the Opus viewer itself - have you seen the Image Viewer Zoom post I made?
The viewer has problems zooming into images that other viewers handle without a problem:

I doubt it's either of those things as it's only done for 1-bit tiff (not things that are more memory intensive), and they would be zoomed out not in.

Send a feature request via the official channel and it might happen. Probably depends if anyone can remember why it's how it is, but the Windows viewer and Photoshop displaying things without scaling certainly makes a case that Opus should do the same.

I doubt it's either of those things as it's only done for 1-bit tiff (not things that are more memory intensive), and they would be zoomed out not in.
true

Send a feature request via the official channel and it might happen. Probably depends if anyone can remember why it's how it is, but the Windows viewer and Photoshop displaying things without scaling certainly makes a case that Opus should do the same.
will do,
thanks as ever :thumbsup:

IIUC, it seems the forum is now where I make an official bug-report/request (I have connected my regristration with my forum account).

Rather than start a new thread about this, I would refer to the OP and note that a file for testing is in post #4

is that okay in the "official" sense? or should I start a new thread?
Thanks in advance.

That's done for the next release.

:thumbsup:

thanks!