MMDT1021 Chapter 5 Notes - page 3

JPEG graphic images.

photo
File name: landcompress1.jpg
File size: 97K

The image with the lowest compression of 1.

photo
File name: landprogressive.jpg
File size: 92K

If you had a slow connection, you would notice that at first the image would be blocky and unclear.  As the image keeps loading, the image will become clearer.

photo
File name: landcompress15.jpg
File size: 29K

The image with a compression of 15.  Notice that the file size has been significantly reduced and the image quality is still very good.

photo
File name: landcompress30.jpg
File size: 19K

The image with a compression of 30.  Notice that the file size has been reduced further and the image quality is still very good.

 
photo
File name: landcompress60.jpg
File size: 11K

The image with a compression of 60.  Notice that the file size has been reduced further. However the image is starting to loose detail and artifacts are appearing in some areas.

photo
File name: landcompress90.jpg
File size: 4K

The image with a compression of 90.  Although the file size is very small, the image quality is very poor.

photo
File name: landgif.gif
File size: 70K

This example shows what happens if the GIF format is used instead of the JPEG format on a photographic quality image.  Notice how the blue hues in the sky look blotchy.  This is due to the 256 color limitation with a GIF.  The GIF format is not recommended photographic quality images.