What kind of pictures are usually hung in hospitals?

Flowers, landscapes and other works are usually hung in hospitals. Of course, it is not limited to these. The main principles are warmth and sunshine. Tones are mainly blue and warm yellow tones that make patients feel calm. The content should be some landscapes, flower oil paintings, flower-and-bird Chinese paintings, and some photographs can also be hung. If it is an oil painting, it can be realistic and freehand, but it can't have too strong emotions in it. The contrast is milder.