In a grayscale image, how can I lighten all pixels that are darker than 50% gray to 50% gray without changing any of the other pixels?
For example, this image:
should become this image:
I have tried using both the levels tool and the histogram. In the levels tool, I only managed to shift all pixel values, including those that are lighter than 50% gray:
In the historgram, I'm unable to draw an edge and the curve always curves around the midpoint:
Is there an easier solution?