Search found 457 matches

by GreenKoopa
2010-11-08T02:31:03-07:00
Forum: Users
Topic: How to extract part of dvd cover image
Replies: 6
Views: 12265

Re: How to extract part of dvd cover image

This sounds like a task easily accomplished using ImageMagick. Check out: ImageMagick v6 Examples > Cutting and Bordering > Crop a Percentage of an Image ImageMagick: Command-line Options > -gravity and -crop If you still can't get it to work, let me know what you have tried and what didn't happen t...
by GreenKoopa
2010-11-07T16:59:39-07:00
Forum: Users
Topic: -fx advice
Replies: 7
Views: 12959

Re: -fx advice

I'm using ImageMagick 6.6.1-1 2010-04-04 Q16 (w/ OpenMP) on an older computer. Most things are very fast, but png compression with quality=90 does take a minute. My image is the result of a modular diff (-compose subtract -composite), so yes I'm rolling the max white value (65535) back to black. Pho...
by GreenKoopa
2010-11-07T15:59:49-07:00
Forum: Users
Topic: grayscale desaturate under a color profile
Replies: 3
Views: 9182

Re: grayscale desaturate under a color profile

I achieved the grayscaling results I wanted by setting a -profile and then using a second -profile to cause a conversion. My hangup was that I somehow didn't realize that grayscale profiles existed. None were on my computer, I had to generate one using Photoshop. My question concerning what operatio...
by GreenKoopa
2010-11-07T15:49:22-07:00
Forum: Users
Topic: -fx advice
Replies: 7
Views: 12959

-fx advice

-fx "(u.r < 0.00002 || u.r > 0.99999) && (u.g < 0.00002 || u.g > 0.99999) && (u.b < 0.00002 || u.b > 0.99999) ? #000 : u" 19 minutes for a 6 megapixel image. Is that normal or am I structuring my expression poorly? This expression simply filters some noise from my image. Each pixel is independent of...
by GreenKoopa
2010-11-05T04:56:23-07:00
Forum: Users
Topic: grayscale desaturate under a color profile
Replies: 3
Views: 9182

Re: grayscale desaturate under a color profile

I think I have concluded the -colorspace operator is not affected by the current -profile . But then how is RGB converted to Gray, Lab, etc. without being well defined (primaries, white point, and such)? If not -colorspace, does -profile impact any operator other than subsequent -profile by triggeri...
by GreenKoopa
2010-11-05T01:32:11-07:00
Forum: Users
Topic: grayscale desaturate under a color profile
Replies: 3
Views: 9182

Re: grayscale desaturate under a color profile

BTW, the images I begin with are in the ProPhoto colorspace and it will hopefully end as a b&w process print . Of course it is also a bit of intellectual curiosity. I've culled luminance , luminosity , relative luminance , luma , intensity, lightness ( HSL ), brightness ( HSB ), Y (various colorspac...
by GreenKoopa
2010-11-04T17:50:25-07:00
Forum: Users
Topic: grayscale desaturate under a color profile
Replies: 3
Views: 9182

grayscale desaturate under a color profile

I have a color image I would like to convert to grayscale. Of course I can use "-colorspace Gray" or "-modulate 100,0", or specify my own channel weightings using numerous methods. But doesn't the color management profile have something to say about this? Does anyone know a gray scale or desaturate ...