Something about images

  • gif images
    • Stands for “Graphics Interchange Format”
    • Good compression with images with solid colors (Logos, graphs, text, simple banners)
    • Offer single color transparency (One of the colors can be transparent, showing the background where it sits instead)
    • It only contain 256 shades, meaning images with lots of colors, like photos, may look a bit “posterized”
    • It support animations composed of several gif images
  • jpeg images (jpg)
    • Stands for “Join Photographic Expert Group”
    • Can contain millions of different colors (ideal for photos)
    • Compression algorithm specialized in color accuracy, but text may lose sharpness and become blurry
  • png images
    • Stands for “Portable Network Graphics”
    • PNG8: Same as GIF, 256 shades, 1 color transparency, but compress better than gif
    • PNG24 and PNG32:
      • more colors than jpg images
      • Alpha transparency (256 levels of transparency)
      • IE6 doesn’t handle transparency too well
      • Files are bigger than JPEG