Raster Images

Raster Images:
Are images that are created up by pixels in a grid, raster images are also known as bitmap graphics and they rely on resolution. Resolution is how many pixels are in that image, which is normally seen as ppi (pixels per inch). an issue with resizing bitmap images is that as soon as they size is changed from what they originally are they loose quality when up scaled however there quality can increase when de-scaling an image this increases the image quality because you are increasing the ppi. When you enlarge a bitmap image the edges of it go all Compression techniques, these are used to reduce the size of a file. The size of a file is important, as a file may need to be sent to another location. Smaller files arrive at the other location faster the big ones. The Only way to make a bigger file smaller is to compress it.

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When editing some images for a previous task i had to use my college logo which was a raster image i had to make sure that it was okay to put onto the images without any of the pixels increasing and stretching when i increased the image size.