JPEG verus GIF

Generally speaking, JPEG is superior to GIF for storing full-color or gray-scale images of "realistic" scenes; this refers to scanned photographs, continuous-tone artwork, and similar material (see Figure 4d).  Any smooth variation in color, such as occurs in highlighted or shaded areas, will be represented more faithfully and in less space by JPEG than by GIF.  GIF is significantly better for images with only a few distinct colors, such as line drawings and simple buttons or logos. Not only is GIF lossless for such images, but it often compresses them more than JPEG can. For medical imaging 64 to 256 grey scaled lossless GIF can be used but files are 100% larger than JEPG and thus will take twice the time to load without any quality improvements (see Figure 4b-c). Such a solution would only be of interest for an image database.

For medical imaging

For publishing on the web: 

• x rays plain films
• CT, MRI images
• photos of procedural material, anatomy or pathology
  

JPEG is actually the best choice.

Figure 4a.  Bmp uncompressed image . Vertebroplasty,  matrix 277*200 pixels, 24bits color, size 166.45k,  load time 42 sec at 28.8kbps(kilobytes per second ).

Figure 4b. GIF image, vertebroplasty. Same image as above, grayscale 64 colors, size 15.6k, load time 4sec at 28 8kbps (kilobytes per second ).

Figure 4c. JPEG image, vertebroplasty. Same image as above. 24bits color, quality 80% no smoothing, size 7.86k,  load time 2sec at 28. 8kbps (kilobytes per second ).

Figure 4d. Gif image logo 202 colors matrix 74*75 pixels size 3.4k load time 1 sec at 28.8 kbps (kilobytes per second ).