Legacy ImageMagick Discussions Archive

Hello Support,

1. We use the ENHANCE tab to brighten and the function works fine.
2. Then we use the EFFECTS tab to sharpen and the sharpen function works fine.
3. However, after using the EFFECTS tab to sharpen, our image is no longer brightened that we did with the EFFECTS tab.

UPDATE: The Sharpen function in the EFFECTS tab actually darkens the image, whether or not any other tabs or functions are used. Version 7.00

UPDATE #2: The above issue still persists with PNG image files. The issue does not affect JPG image files.

Any assistance would be appreciated.

Thank you for your time and consideration.

ArtView

I see no such problem when using http://www.imagemagick.org/MagickStudio ... Studio.cgi. I am on Mac OSX. It does not darken when using -gamma then -sharpen with the defaults or even just -sharpen.

UPDATE #2: The above issue still persists with PNG image files. The issue does not affect JPG image files.

It still does not darken for me with a 128x128 zelda3.png file. Try this one:




Does it happen for all PNG files?

Thank you for your reply.

Tested your image zelda3.png and all is well, there is no darkening the image when using the EFFECTS tab -sharpen. Also tested other PNG files, per your inquiry, and all is well, with the following exception:

when editing video, and a snapshot is taken of a frame, a PNG file is created. All PNG files created from the video editing software I am using, experience the darkening effect when using IM - EFFECTS tab - sharpening. Strange but true.

The work around is to use an interim step and save the PNG file (created by the video editing software) as a JPG file, then upload to IM for changes. Then all is well, no darkening effect.

Any comments or observations would be appreciated.

Again, thank you for your time and interest.

ArtView

Post an example of the PNG file that does not work. We can review it to see what the issue might be. You can upload the file to some free hosting service (that does not change the format) such as dropbox (public folder) and put the URL here.