Ratio Crop
This module adds an image style effect that crops images to a specific aspect ratio without resizing them. Instead of fixed pixel dimensions, you define a ratio, and the excess parts of the image are cropped away to maintain that ratio. This is useful for creating images of varying sizes that share the same proportions.
This module provides an image style effect that crops image to predefined ratio without resizing it. So, instead of setting width and height parameters in pixels as you would for core crop effect, you need to set up an aspect ratio, and the protruding dimension will be cropped, keeping another dimension intact. This way you can get images of different sizes with same aspect ratio (which can be useful, eg, for some zoom gallery).
There are more sophisticated modules such as Image Widget Crop or Focal Point which provide widgets with control over every single image.