High contrast black&white

Questions and postings pertaining to the usage of ImageMagick regardless of the interface. This includes the command-line utilities, as well as the C and C++ APIs. Usage questions are like "How do I use ImageMagick to create drop shadows?".
Post Reply
PlinkPloink
Posts: 1
Joined: 2013-10-26T02:46:13-07:00
Authentication code: 6789

High contrast black&white

Post by PlinkPloink »

Hi everyone,

I'm looking for help on using ImageMagick for converting colour/grayscale images to more intense black/white.
A bit of the look i'm trying to get is this: http://www.wowitsalightbulb.com/photogr ... otographs/ and http://inspirationhut.net/inspiration/i ... n-stavars/

I did read a lot of documentation and used google for some examples but I just cant find a way to apply it with ImageMagick. When I convert my images to grayscale then the amounts 'colors' from pure white to pure black is pretty big. I don't know how its called but I think tonal range ? But for the look I'm trying to achieve I think I need less tonal range... But correct my if I'm wrong! :)

So is there a way in ImageMagick to limit the tonal range? I'm not looking for pure black and pure white but for for example split the range from pure white to pure black in 10 steps ? I use ImageMagick from the commandline version: ImageMagick 6.8.7-0 2013-09-19 Q16
snibgo
Posts: 12159
Joined: 2010-01-23T23:01:33-07:00
Authentication code: 1151
Location: England, UK

Re: High contrast black&white

Post by snibgo »

You can easily limit the tonal range, with "+level". But I don't think that's what you want.

IM contains a large range of tools for manipulating monochrome images: adjusting tones, contrast, lightening and darkening (dodging and burning) with masks, as so on.

However, it isn't interactive. This means that unless you know what effect you want, and how the tools work, it isn't easy.

Gimp has many similar tools, and is interactive. This make it much easier to "play", to discover what is possible and how. Gimp is only 8-bit, which is a major limitation for monochrome, but you can learn a lot with it, and very much faster than using IM.
snibgo's IM pages: im.snibgo.com
User avatar
fmw42
Posts: 25562
Joined: 2007-07-02T17:14:51-07:00
Authentication code: 1152
Location: Sunnyvale, California, USA

Re: High contrast black&white

Post by fmw42 »

If you use Photoshop or GIMP to get what you want and then have a lot of photos to process the same way (exact same commands and values), then you can do that with IM. You can either experiment to find equivalent operations (and we can probabaly help if you can provide and input and output example). Or you can transfer the characteristics of the change from PS or GIMP using a HALD image and the in IM use the hald image with -hald-clut to apply it to all the images you need.

Of course if each image needs different processing, then you are better working with an interactive tool.

You can also experiment with the interactive Jqmagick online at http://jqmagick.imagemagick.org/
Post Reply