Legacy ImageMagick Discussions Archive

snibgo wrote:

eg bottom pixel 50% transparent (ergo 50% opaque)
top pixel 50% transparent (ergo 50% opaque)
result i want: 0% transparent, 100 opaque.

Make the bottom pixel opaque. Job done.

Thanks Snibgo and all others who helped here.

cool, thanks for help, i have got it to work like this make wizard jpg curl http://www.imagemagick.org/image/wizard.png > wizard.png convert wizard.png wizard.jpg make 1 gradient convert -size 1468x1104 gradient:'white-black' -rotate 90 -set colorspace RGB -colorspace gray -gamma 2.2 r2l.jpg make 2 ...

Have you tried convert ORIGINAL.JPG -alpha set -channel a -evaluate set 50% +channel PNG32:IMAGE_ALPHA.PNG fmw42, thank you, that would work for a flat, constant 50%, but I need to create graduated fades as masks. My example was just trying to solve 50% for convenience. I need to solve for every ...

thanks for taking the time to help. silly me regarding the IM version etc. I'm am using 6.8.0-7 from macports. Unfortunately I can't use the 50% transparency you suggest, because what I'm actually trying to do is create a black-grey-white graduated fade to be used as the alpha. For example on image ...

Hello all I am trying to get 50% transparency using an alpha mask. I have created a grey jpg for my alpha that uses rgb 127 values. I am using this technique: convert ORIGINAL.JPG -background none -alpha Off GREY.JPG -compose CopyOpacity -composite PNG32:IMAGE_ALPHA.PNG But the grey i use is not ...

thank you anthony

Thank you bonzo and fmw42 for taking the time to help me.

fmw42 I have got that shell script working. I am going to abandon the perl script. I will mess around with it now and hopefully come up with the results i am after.

Thank you once again.

Nope Bonzo, I see none. My perl script is exactly the same as this one, bar the path to perl
http://www.imagemagick.org/Usage/script ... _curves.pl

Hello all I am battling with the im_fx_curves.pl script provided on the imagemagick site. this is a perl script that allows you to make adjustments similar to photoshop curves: http://www.imagemagick.org/Usage/scripts/im_fx_curves.pl the only modification I have made to the script is changing the ...