have you already tried doing this process?
You can tune up your photos in the Gallery app in a number of ways, including altering the brightness, contrast, colours, size, and adding effects.
From the Home screen touch Apps 
> Gallery 
and open a photo. Touch the photo and then touch More options 
> Studio > Photo studio to edit the photo.
The following options are available:
 | Enhance: One-touch photo enhancement adjusts contrast, brightness and other settings to improve the quality of the photo. |  | Adjustment: Open tools to Rotate,Crop, or Resize the photo. |
 | Tone: Add colour enhancements, such as Brightness, Contrast and Hue. |  | Effect: Add various stylised effects, such as Vignette, Vintage, Grayscale and Sepia. |
 | Portrait: Make adjustments to facial features, such as Remove red eye, Brighten face and Airbrush. |  | Decoration: Add decorations, such as a Sticker, a Frame and Drawing. |
Touch Undo 
to reverse the most recent edit made to the photo or touch Redo 
to reverse the last Undo step. Touch Cancel 
to disregard all changes made in edit mode. Touch Save 
to save your changes. A new file will be created and the original file will be left untouched
if in any case this is still not working, you can call the customer service of Samsung because this is more about the phone itself. :
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