How to create text annotation over a place of subplot

I'm trying to draw the statistics section but I couldn't do it.

% figure 
    figure, subplot(2,3,1), imshow(I), title('Original');
    subplot(2,3,2), plot(x,y,'LineWidth', 3), axis([0 255 0 255]), title('Transformation function: I = I+128'), axis square;
    subplot(2,3,3), imshow(I1), title('I+128'); %display
    subplot(2,3,4), imhist(I), title('Original Histogram');
    subplot(2,3,5), annotation('textbox','String',str)
    subplot(2,3,6), imhist(I1), title('Modified Histogram');

The annotation part is not working like i want and gives this output

Answer 1

[Star Strider]

In the documentation Create Text Box Annotation, the textbox can take a dim vector that describes the size and location of the textbox. Experiment with those values to create the correct size and position for it.

Alternatively, use a text object in the specific subplot. That might be easier.