Contrast & Brightness filter effect feature

Is there any way to adjust the contrast of an image in OmniGraffle? I’m also interested in other classically available adjustments like brightness, exposure, sharpness, saturation, etc. If contrast is available then I’m sure those are too.

I understand that OmniGraffle isn’t primarily an image editing app, but even apps like Microsoft Word have this feature, and that’s a word processor app, so I imagine OmniGraffle has some way. If it doesn’t have it, OmniGraffle already has the engine built in to do so (see B&W filter below), so hopefully this would be an easy feature request to implement:

I did find a solution for achieving B&W / desaturation at the links below, as well as a variety of what I’d think are rarely needed effects compared to contrast etc. But it doesn’t seem like classic contrast and similar adjustments are available? Nor the ability to adjust the amount of the effect.

https://support.omnigroup.com/documentation/omnigraffle/ios/3.19/en/blend-and-filter-types/
Applying a color mask to change underlying image?
Convert image to black and white - #4 by fjordaan

I think this is what you want:

  • select your image
  • open the Inspector
  • scroll down to Image and Opacity
  • you can either type in a number or use the slider to adjust

Thanks, but I don’t think that’s contrast control, unless I’m using it incorrectly. Opacity just controls how transparent it is, that’s different from contrast (or brightness etc). If the entry field accepted a value above 100%, like let’s say 200%, then maybe it would’ve behaved as contrast increase, but it doesn’t go above 100% for me to test.

But that makes me realize, there’s an image section under the Inspector, so yet another and better place Omni could add contrast/brightness/etc controls with a slider. Something like these controls from Preview.app:

Nothing like that. About all you might be able to do is apply some filters over your image…but I don’t think that is what you want either.

I’d be fine with that, but all of the filters are odd / rarely used / 2nd order, especially in comparison to the basic effects I’m looking for. Also, there doesn’t seem to be a way to adjust the degree of those filters, unless I’m missing something.

I have only used them a little toi help with some color changes of layers so someone with more experience will have to chime in to help.