display image in smaller size

Hi all,

Is it possible that display an image (smaller than actual width and height) in datalist without affect the image quality its actual height and width ?

for example :

i got an image (image1, height = 500px and width = 450px)

but when i display it in datalist, i wan its height = 200px, width = 175px

i wonder if i directly set the image height = 200px, width = 175px(in datalist), its quality will be affected or not ?

i am sure that if the actual image (height and width) is smaller.....then for sure its quality will be affected...

thanks
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