Is there a way I can resize, crop, and center an image using html/css only? (img tag or css sprite)

For example if I have a 500x500 pixel image,

1. I want to resize that to a 250x250 pixel image

2. I want to make the actual visible image to be 100x100, but still have the scale of a 250x250 sized image.

3. I want the center of the image to be at a location x,y.

Is that possible with only html/css, if not, how do you propose I go about it with javascript?

Edit - ????:

For (2), say my scaled image is now 200x200, and I want my visible image to be 100x100: So I guess what I mean is I want the scale and resolution of the image to be 200x200 but I want the visible image to be 100x100 or in other words the visible image would be at coordinates x,y: 0,0; 0,100; 100,0; 100,100; of the 200x200 image. Sorry, but I'm not good at explaining this.