montage concatenate with null:

[sebunger]

Hi,

I'm trying to combine a number of images with equal dimensions into a single image by concatenating them without border or any decorations. However, sometimes I need to leave some of the tiles blank. I've tried this command line, but it seems to behave oddly (and contrary to documentation):

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montage -mode concatenate -tile 2x2 rose: rose: null: rose: im_example.png

I expected an image with 3 roses and a white field in the bottom left. however, I get this:



Am I doing something wrong or is this a bug?

Thanks for your help,
Seb

[fmw42]

It seems to work this way:

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montage -tile 2x2 -geometry 70x46+0+0 rose: rose: null: rose: result.png

but oddly, if you leave off the WxH, I get your same result

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montage -tile 2x2 -geometry +0+0 rose: rose: null: rose: result.png

I suspect that without the WxH, montage does not know what size to make null: and so skips it.


Also if you leave off the geometry, it works fine, but you get lots of white space

Code: Select all

montage -tile 2x2 rose: rose: null: rose: result.png

[sebunger]

Yes, those are my exact results. The problem is that I don't necessarily know the geometry of the individual images, only that they are the same. I guess I could query that information and then use it in my script, but according to my understanding of the docs I thought it should work. Hence my post here.