An image rendering method for a computer product coupled to a display apparatus may include rendering an entire display region of the display apparatus with a first rendering mode to generate a first rendering mode sample image, determining a target region in the entire display region, rendering the target region with a second rendering mode to generate a second rendering mode sample image, and transmitting data of the first rendering mode sample image and the second rendering mode sample image. The second rendering mode comprises at least a value of an image rendering feature that is higher than that of the first rendering mode.