Why are my digital photograph files so huge while photos on other Web sites are much smaller?
If you are designing a Web site , sending digital photographs as e-mail attachments or trying to pack as many images on a floppy disk as possible, the size of each image is important. What you want to do is shrink the file size to as few bytes as possible without hurting the image quality. Most Web sites that publish photographs use the JPEG (pronounced “jay-peg”) format for their images. JPEG is a popular format for two reasons: • It has good compression characteristics on photographic data. • It lets you adjust the amount of compression. Sites like BBCi and CNN.com adjust the compression ratio to shrink the file size. Most image-handling programs let you tweak the JPEG compression ratio in one way or another. For example, Paint Shop Pro lets you adjust the compression ratio on a scale from 1 to 99, with 1 offering the best image quality and lowest compression ratio and 99 offering the lowest quality and highest compression. The following images give you some sense of the effect that
