DPI and PPI | DPI OR PPI

Question

Is there any differ between DPI and PPI ? Is it true : Dot = Pixel ? And at Last what is DpiX and DpiY in C#.net ? How can we change them ?

Answer 1

DPI

Stands for Dot Per Inch and is used when pritning. It is also heavily misused with screen resolution. A colour ink printer don't mix the colors, instead each color has its own "slot". When a printer says 12000 dpi it is actually 12000 / 5 "pixels" for a 5 color based printer. Never the less, DPI only becomes interesting in the context of a printed result. Photoshop use the image's DPI information to be able to tell you the printed size of the image. Many people missinterpret DPI as a measurement of the pictures image quality or pixel density. For example, if you change the DPI for an image in Photoshop without resampling the image, you still have the exact same amount of pixels but now photoshop shows another "physical" dimension (inch or whatever you use).

Look at this Wiki article .

PPI

Stands for Pixels Per Inch (or pixel density) and should be used with screens and defined as one pixel equals the area of all the three base colors (Red, Green and Bue). Look at this Wiki article .