Graphic File Formats

    Understanding Format, Choice Image, and Compression.              

• Compression: Makes something a smaller file size, but the quality is worse.  

File format

• All computer documents, or files, are packaged in different formats
• The format is determined often by the files origin, such as a software program like Photoshop, or a device such as digital camera
• Compression throws away "unneeded" data

• Lossy vs Lossless
• Lossy: extra data is moved into the trash, much much smaller file size. Very low quality.
• Lossless: throws away a little data, but retains more quality  
• lossless: Tiff
• lossy: Mp4, GIF

Lossy                             Lossless

Graphic Formats

• TIF(Tagged Image Format), JPG(Joint Photographic Group), and GIF(Graphic Interchange Format) are the 3 most common formats for common activities.
• PNG is a common web format, is high quality and can contain an alpha (transparency) channel

TIF

• Common format for desktop publishing, print, photo and graphic design
• Reatians max quality
• Larger files, not internet friendly 

JPG

• Created for digital photography and works best for photo content
• Is lossy
• Can reduce file size for 10:1 without showing significant compression artifacts
• Adjustable compression
• Not animatable, No alpha channels

GIF

• Gif is good for Cartoons/ Graphics
• Best internet friendly, for flat colors
• Reduces size by "indexing" color from 3 channels 1
• Is adjustable by changing color bit levels from 1 to 8
• Contains no DPI (Dots Per Inch) data for printing. Not proper format for print.
• They can be animated, they have frames. 

Know your pixels

• Tif and Jpg are best for images with pixels that blend in color, these are called "contagious pixels"
• Gif is best for images with flat even tone, or "noncontiguous pixels"

Aliased = jagged

Anti-Aliased = Smoothed out. It tries to blend colors.