Search found 43 matches
- 2015-05-13T03:32:59-07:00
- Forum: Users
- Topic: Making a new 16-bit Lab color
- Replies: 5
- Views: 4745
Re: Making a new 16-bit Lab color
After trying out your advice, I can conclude two things: * Using decimal precision does indeed work, so I can reach my desired values by using (0,-0.87109,0.79067) * As alluded to above, negative values do seem to work (for a & b channels, at least) in non-HDRI mode If you use -colorspace lab an...
- 2015-05-13T01:35:51-07:00
- Forum: Users
- Topic: Making a new 16-bit Lab color
- Replies: 5
- Views: 4745
Re: Making a new 16-bit Lab color
That's very helpful, thanks! I'll use that format instead. Just out of curiosity, how come my second line (0,-2,2) works with negative values, when I'm not in HDRI mode?
- 2015-05-12T11:18:51-07:00
- Forum: Users
- Topic: Making a new 16-bit Lab color
- Replies: 5
- Views: 4745
Making a new 16-bit Lab color
Version: ImageMagick 6.9.0-10 Q16 x64 Hi, I'm having trouble setting the canvas a very specific color. The line I want to use would look like this: convert -depth 16 -size 2700x5120 -colorspace lab xc:"lab(0,-223,204)" output.tif But that produces the following 16-bit Lab values: 0,16256,1...
- 2015-04-28T08:50:50-07:00
- Forum: Users
- Topic: Issue with resize percentage (DDS)
- Replies: 3
- Views: 4155
Re: Issue with resize percentage (DDS)
Also, is your -filter aimed at the -resize command? If so, it should appear before, not after:
Code: Select all
mogrify *.dds -filter Mitchell -resize 50%% -sharpen 1 *.dds
- 2015-04-28T08:29:49-07:00
- Forum: Users
- Topic: Photoshop color conversion vs IM color conversion
- Replies: 3
- Views: 3372
Re: Photoshop color conversion vs IM color conversion
The solution for matching PS was: convert input.tif -profile myprofile.icc -intent relative -black-point-compensation -profile sRGB.icc output.tif even though in PS I had converted from myprofile.icc to sRGB via Perceptual intent! When I wrote: If I use -black-point-compensation and -intent options ...
- 2015-04-28T05:21:52-07:00
- Forum: Users
- Topic: Photoshop color conversion vs IM color conversion
- Replies: 3
- Views: 3372
Photoshop color conversion vs IM color conversion
Version: ImageMagick 6.9.0-10 Q16 x64 I have created an ICC profile that I apply to my images. I use this command to apply it to my TIFF files (hitherto without profile): convert input.tif -profile myprofile.icc output.tif When I open output.tif in Photoshop, Photoshop notices the profile and displa...
- 2015-03-20T05:28:06-07:00
- Forum: Users
- Topic: Average location
- Replies: 1
- Views: 2024
Average location
I'm trying to use ImageMagick to find the location of a calibration target in an image. I've written enough code to output a b&w (i.e. bilevel, not grayscale) image, which looks like a small black square on a giant white background. I've used the following code to find the location of the all of...
- 2015-03-20T05:11:13-07:00
- Forum: Users
- Topic: Photoshop blending mode "Darker color"?
- Replies: 2
- Views: 3709
Re: Photoshop blending mode "Darker color"?
Darker color compares RGB (total) from image A and with RGB (total) from image B and chooses the pixel with the lower total value. This way, no new colors appear in the composited image. This is different from "Darken" which does this on a per channel basis, often creating colors that were...
- 2015-03-12T09:03:41-07:00
- Forum: Users
- Topic: LAB channels don't behave during threshold
- Replies: 3
- Views: 4047
Re: LAB channels don't behave during threshold
@Snibgo - thanks very much for your answers. I didn't realise PNG didn't support Lab, so tricking imagemagick didn't cross my mind. Great solution!
- 2015-02-26T10:56:54-07:00
- Forum: Users
- Topic: Threshold & separate outputs a bilevel rather than a grayscale
- Replies: 4
- Views: 4276
Re: Threshold & separate outputs a bilevel rather than a grayscale
I've tried:
to no avail, by the way.
Code: Select all
convert input.png -colorspace lab -channel G -separate -threshold 50% -channel G -separate -type grayscale output.png
- 2015-02-26T10:40:18-07:00
- Forum: Users
- Topic: Threshold & separate outputs a bilevel rather than a grayscale
- Replies: 4
- Views: 4276
Threshold & separate outputs a bilevel rather than a grayscale
When I threshold a channel and then use -separate to save only this channel, the image I get is in 'bilevel' mode (acording to identify), rather than grayscale. I use this line: convert input.png -colorspace lab -channel G -separate -threshold 50% -channel G -separate output.png And obviously I'm ex...
- 2015-02-26T08:54:08-07:00
- Forum: Users
- Topic: LAB channels don't behave during threshold
- Replies: 3
- Views: 4047
Re: LAB channels don't behave during threshold
Turns out I needed to -separate again:
Thought I'd leave this here for anyone else confused by separating channels.
Code: Select all
convert input.png -colorspace lab -channel G -separate -threshold 50% -channel G -separate output.png
- 2015-02-26T08:43:20-07:00
- Forum: Users
- Topic: LAB channels don't behave during threshold
- Replies: 3
- Views: 4047
LAB channels don't behave during threshold
I'm having trouble getting the result I want while using ImageMagick 6.8.9-5 Q16 x64 on Windows 7 64bit via Cygwin. I want to take an input image, convert it to LAB colorspace, apply a threshold on the 'A' channel, and output this as a grayscale (more specifically black&white, as a threshold sho...