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- Animation - You can tie together multiple images to create animation.
The problems of GIF are:
- GIF uses a proprietary encoding/decoding scheme called LZW (Lempel Zev Welch). This scheme is patented by Unisys, who has been sending out letters demanding compensation from some companies who have created commercial image applications.
- GIF images can only include 256 colors.
JPEG (Joint Photographic Experts Group) - Another very common format on
internet. JPEG (also known as JPG) images use a lossy compression scheme. This means that as you optimize your image bits are removed. When
image is decompressed,
bits are interpolated. This means that as you use greater and greater compression, your image tends to get fuzzier and fuzzier.
This format is best for images with gradients, such as paintings and photos. Images with sharp definition, such as clipart and text, should be saved as GIF or PNG.
JPEG images can often be compressed to smaller sizes than
exact same image in GIF format, although some definition may be lost. Depending upon
image, this may or may not be important.
The main reason why JPEG images would be used instead of GIF is that JPEG's support more than 256 colors.
PNG (Portable Network Graphics) - PNG is a new, up-and-coming format. PNG has all of
features of GIF except for animation, and PNG has
advantage of allowing for more than 256 colors. In addition,
compression algorithm of PNG is public domain and non-lossy (bits of
image are not lost), which makes it superior to both GIF and JPG.
All of
newer browsers support PNG format, including Netscape and Internet Explorer. You should still use this format with caution, as older browsers do not support it at all. Thus, if you use
format you are more-or-less locking out those who have not upgraded their browsers.
