Zoom to Selection

[jsc37227]

Don't scold me if this has already been discussed - I couldn't find anything that matched exactly. It's also why I am posting here and not in the bug report area - I may be doing something wrong.

Used to be that if I dragged a selection then clicked within the selection, the image would zoom to that selection area, with whatever the magnification happened to be. Now, with 4.23, the zoomed area is rarely centered in the selection box - I have to scroll to where I wanted to be centered.

This is for ccitt group 4 b&w tiff images, starting from "F" fit to window, with resampling, and with "center image in window" checked.

Generally, the old versions would zoom to the selection without resampling, and I'd hit the grey+ key to resample at a slightly higher magnification.

The problem I am having now with 4.23 (4.20 may have been similar, I don't remember exactly when this started), is that the zoom to selection is way off. I've tried clicking different corners of the selection box, but nothing seems to matter.

Is there a new trick to make this work?

[Mij]

Yes I think I see what you mean. Select say a small square area in the middle of the image and then click in it to zoom. The area you selected is now not in the centre of the screen, but off to the right. It seems that it zooms about the left hand edge of the box not the centre of it.

[Frank]

May be it's one of these following options:

• the option "Center image in window" to find in program menu of IrfanView in: \View\Display options (window mode)\
• the option "Center window when loading new image" to find in program menu of IrfanView in: \Options\Properties/Settings...\Misc. 2\
• the "Zoom options" to find in program menu of IrfanView in: \Options\Properties/Settings...\Viewing\

see:

(Click to view full size!)

[jsc37227]

"Center image in window" doesn't seem to make a difference on this issue.

"Center window when viewing new image" also no affect on this issue. (New window just comes up centered on the screen.)

I've got Zoom step at 5% and "fixed values" checked. Not sure why this would have any impact.

To tell you the truth, there is some randomness about it. Sometimes the zoomed image is mostly centered on the selection, but many times it zooms off to the left quite a bit.

It used to be quite reliable at centering your selection, but I think starting with 4.20 (maybe earlier) it's been a nuisance.

[Skippybox]

I feel like we've been down this road before. We know IrfanView is poor with selection accuracy, so what can we expect? Perhaps the randomness you talk of jsc37227 is why seeing the problem can be difficult. Most images do look centered (although, should we assume they are supposed to be?), but I would agree that others aren't. I don't even think that it is just to the left either. I would say it occurs in other, maybe, all directions.

[Mij]

This one is driving me nuts. I have been using the attached image, setting the selection box to either the red or the blue square and clicking inside the selection to zoom.
Sometimes it ends up central, sometimes off to the right, sometimes bottom right. I cannot find a consistent pattern.

[Skippybox]

Now you see what I'm talking about. Apparently, there is quite a bit of voodoo in IrfanView!