A few months ago Google added a few little options to Slides through your Google Drive that let you crop and add borders. Today they have announced, and added, the ability to fine tune the image in slides a little more.
With the new editing options you can adjust the transparency, brightness and contrast of your included image. You can also recolor the image to make it better match the Slides as well. One step closer to having all the tools needed in one app for creation and editing. I imagine this editing feature will find its way to other Drive applications in time. Pop into Slides on your desktop or laptop and check it out.
Source: Google Via 9to5Google