Hello Students, here are some notes on understanding pixels in photoshop. This is important to understand for our next assignment, drawing an icon/avatar.
Alias vs Anti-Alias:
In Photoshop and other bitmap/pixel based programs, Anti-Aliasing is used to give objects a smooth appearance when viewed on screen, it averages the pixel colors to create a smooth transition.
Aliasing is when graphics lack that smoothing, and we can see jagged edges to the object, or "Jaggies".
Contiguous vs Non-Contiguous:
It is important to understand the difference between contiguous and non-contiguous imagery, because different image compression formats are best used for certain types of images.
Contiguous images have subtle color changes from one pixel to another, such as photograph's, paintings, hand drawn sketches or any graphics with a lot of gradients. The JPEG compression codec is best for these kinds of images, that is why most digital camera's save images in the .JPG format.
Non-Contiguous Images have large areas of flat color, shapes and lines. These can be photo's that have been converted to 8-bits, or graphics drawn without anti-aliasing.
