Hey folks!

I'm pretty much a newbie with Inkscape, and have lots of fun with it so far. However, I've been trying to do this simple act of adjusting the brightness of a bitmap (which was originally a jpg image). I found out that you have to use the "Modulate" feature under Effects > Raster to do that. But when I apply the settings, the image goes black! I used the "Live Preview" feature to see if the values I entered made it so. Even at the default of 1.0 for Brightness and Saturation still made it black. Gosh, have I missed an obvious step? For now I'm using the "Colourize" function to do the brightness thing.

Am using version 0.46, and the image is a small water texture. I know i've got other ways to change the brightness of the bitmap (like using other software to do it before importing), but I'm a little curious as to why the Modulate feature causes the image to be black.

Looking forward for your responses. Thanks in advanced! =) My apologies if this question has been answered before.

I've never touched this feature before, but looking at it now it seems a little confusing and doesn't seem to work properly.

I found that no matter what hue value I set, the hue seems to rotate 180 degrees. Also, the default values for brightness and saturation should be 100 each--at this value you should see the image with no changes.

Now here's the catch, you can't use a value above 100 to make the image brighter. You can only go down from 100 to make your image darker (which is why 1 gives you black). This is true for saturation as well.

Until this is fixed, you might like to edit your jpg in another program first.

Oh, 100 is the normal level? Figures.. I thought the 1.0 was a relative value

Thanks for the reply, microUgly! Hopefully they'll fix this in the next version.

Looking at http://screencasters.heathenx.org I saw the "Modulate" feature working as expected!
At the contrary I get the black picture mentioned above (Windows PC, tried both stable and development releases).

How did they make it working in the screencast? What is the trick?
Is a bit annoying to exit Inkscape to make a quick adjustment like brightness or contrast...

Thanks in advance!

Without actually watching the screencast, I can say that it might be because he was using an older version of Inkscape, or the feature works correctly on whatever OS he was running (Ubuntu?) and not yours.

Honestly, rather than trying to get this to work in Inkscape, you should download the open source graphics editor, the Gimp.

I don't really know why you get black blocks, but most problems with effects I had where because some dependecies where not met. Perhaps you need (lib)imagemagick installed?

With Inkscape 0.47 it will be possible to right click on any bitmap and select from menu "Edit externaly" option, which will "transfer" bitmap to Gimp. There you could do anything you want with the bitmap and after saving it, your changes will be automaticly visible in Inkscape. This funcionality is already available in SVN and it sooo handy, although has one annoying bug which I hope will be fixed soon.

I just tried installing imagemagick but it makes no difference.

I have Gimp installed and tried the "Edit externally" feature, too, but no luck: I get an "Invalid argument" message in status bar and nothing happens.

Sad these little things don't work well, I guess they wouldn't demand much time to get it right.

Just open the bitmap up in gimp, then save and open in Inkscape.

OK, so an adequate answer is: hide not working features.

Theoretically, since it's open source, some random dude can code his own fix using that framework.

Carrozza wrote:I guess they wouldn't demand much time to get it right.

Sounds like you just put up your hand. We look forward to your patch

OK, got it, it's open source so "learn python and do it yourself"; well at the moment I prefer to create skin graphics.

I asked only because I saw this specific feature working in that video and thought it could be a little setting wrong in my install.

Nevermind, keep up the good work, Inkscapers!