Characteristics of Bitmap Data: Bitmap data can take up many rooms. A CMYK A-4 size picture which is optimized for medium quality printing (150 lpi) takes up 40 Mage Bytes. Compressions can decrees the size of the file.
The image along with the enlargement demonstrated one of the major disadvantages of bitmap images as: one time they are enlarged so much, they look blocky and unnatural. But decreasing a picture too much also has a bad affect as it loses sharpness.