Hi Asiye,
As per my understanding, your question is about the loss of image resolution while downscaling. Down scaling an image always leads to loss of image resolution as you lose some of the original image data.
However, there are interpolation methods which you can use to improve the image resolution. Example: Bilinear, bicubic, nearest etc.
I = imread('img.jpg');
J = imresize(I,0.4,'nearest');
You can also define a custom interpolation kernel and then resize images using the custom kernel. Here is the documentation to Create and Compare Resizing Interpolation Kernels
