What is a GIF file
GIF is the internet’s favorite image file type due to its abilities to animate images. GIF files use bitmap images and allow up to 8 bits/pixel. This allows 256 colors in the 24-bit RGB color space. Not all GIF images are animated; many logos and images with sharp, defined lines and edges, and a transparent background utilize the GIF extension. Compression for GIF files is lossless so the size is reduced without changing the quality. This allows the file to be converted to another file type without excessive loss of quality.
Compuserve created the GIF (Graphics Interchange Format) for online use and made the information available to the public. The 256 colors per GIF image is capable of using the LZW (Lempel Zev Welch) form of file compression which removes the inefficient sections of data to reduce the decrease of quality of the image and ensure a better quality image. The raster data is compressed to the minimum file size. The number of colors needed in the image is reduced by removing the colors not being used in the image. The maximum available colors is 256 but it can have as few as 2. The 2 minimum colors needed for a GIF image are black and white. Fewer colors lead to more efficient compression of the file.
Here's a small, but not exhaustive list of programs that can open GIF documents:
- Adobe Photoshop
- Microsoft Windows Photo Gallery Viewer
- Apple Preview
- Corel Paint Shop Pro