Legacy ImageMagick Discussions Archive

But I want to start the first cut at the bottom of the image, not at the top. How can I do this? Adding "-flip" before and after the "-crop" operation seems to work: convert -flip -crop 800x1200 -flip input.png output_%d.png How can I set, that it only takes 3 images and after t...

why do you think the gamma chuck in redundant? Like the "-define" documentation says: " As a special case, if the sRGB chunk is excluded and the gAMA chunk is included, the gAMA chunk will only be written if gamma is not 1/2.2, since most decoders assume sRGB and gamma=1/2.2 when no ...

That works, thanks.

But why does "montage -strip" not do it it in the first place? Is it a bug? The montage option summary does list -strip as a supported option.

Even with the "-strip" option, "montage" outputs a PNG with a redundant gAMA chunk: $ montage rose: -strip PNG:- | identify -verbose - | grep 'png:' png:bKGD: chunk was found (see Background color, above) png:cHRM: chunk was found (see Chromaticity, above) png:gAMA: gamma=0.45454...

Good to know, thanks!

But "-distort" is responsible for extending the virtual canvas in this strange way, isn't it?
Is it supposed to do that?

That seems to work in my case, thanks!

I'm still a little worried about the "-distort resize" behavior though, since I don't understand why it happens.

This command: convert netscape: -distort resize 100x100! -flatten x.png Results in this image for me: https://i.imgur.com/xDN0n8d.png Note the image size of 102x102, and a 2px green border on the bottom and right egde. When I run the same command with " -resize " instead of " -distort...

fmw42, I ended up using your approach, and it is working well. But I have a follow-up question: Why do you do this... \( -clone 0 -alpha extract \) \( -clone 1 -scale x1! -scale $dim! \) -delete 0 instead of just this? -alpha extract \( -clone 0 -scale x1! -scale $dim! \) It seems to work just as we...

Understood, thanks.

PS: I didn't realize that IM 7 is already in beta. Nice!

Thanks for the reply fmw42! What would you consider the advantages of this method? (From what I can see, the text output is easier for the shell script to parse than with my method, but in return it needs one extra convert call - to get the original image dimensions. Would it be possible to avoid th...

Consider an input image that was created by horizontally appending three opaque rectangular images on a transparent background, for example: convert \( logo: -resize 35% \) rose: granite: -background Transparent -gravity North +append input.png http://i.imgur.com/ijeNZWb.png The problem Given an ima...

Huh, you're right, it does work. No idea what I did wrong when I tried it yesterday... :oops: Thanks for responding! You could add a little -fuzz XX% in case some values are not quite at gray2. But in principle, you commands should work. I'm not replacing gray2 pixels, I'm replacing a range of pixel...

I'm trying to darken and blur a grayscale PNG image, and then replace all pixels which are darker than gray2, with gray2. This works fine: convert a.png -level 0%,85% -blur 0x5 b.png convert b.png -black-threshold '2%' c.png convert c.png -fill gray2 -opaque black d.png However if I try to combine t...

Anyways, you're right that this fuzzy " compare -subimage-search " is very slow. If I were to add the additional assumptions that... each occurrence of the search image inside the source image is a pixel-perfect copy of the original search image (except of course for pixels which are trans...