My notes

• All computer docs or files are packaged in different formats
• format of the file usually defined by the files origin
• compression of files throws away uneeded data

• 2 categories of compression, lossy and lossless
• lossy makes it poor quality
• lossless makes image HQ but is larger file

• TIF tag image format. for HQ printing. common format for desktop publishing, printing, photo and graphic design. not internet friendly. contains lossless for max quality
• JPG image compression scheme mad for photographs. lossy format. can reduce file size to 10th of original without reducing quality too much. only works with photos, not for graphic images
• GIF graphic interchange format. made for flat color in image. reduces image size by indexing color for 3-1 channels. contains no dots per inch(dpi) for printing.
• PNG is common web format HQ. Can have alpha (transparency) panel. you can make shapes out of documents
• Tif and jpg are best for images with pixels that blend in color call “contiguous pixels”
• gif is best for images with flat even tone or “non-contiguous pixels”