Digital Graphics

Raster Graphics

Raster Graphics are made up of tiny rectangular squares called pixels. Each small square is given one colour, when you zoom out away from these pixels they come together and show a picture just like how a collage shows a picture when you back away from it.


Advantages of Raster Graphics
Even though it uses this method of using tiny pixels to make the images, the image looks very realistic when it is viewed at its proper size.


Disadvantages of Raster Graphics
There are limitations to using Raster Graphics, when zoomed in the picture becomes blurry and the pixels are easier to see making it hard to zoom into a photo and keep the quality of the picture.


Vector
Vector graphics use mathematical equations to create the image. These mathematical equations mark out points, lines and curves of the image.


Advantages of Vector
The images can be scaled with out any loss in quality. The picture also don’t take up a lot of disk space.


Disadvantages of Vector
Computers have to work harder so that the picture can be displayed so this may result in the image taking longer to be processed. They cannot be used to display photographs or any other complicated pictures.


Compression

Compression is used usually to reduce the size of images. Images can be compressed as either Lossy or Lossless.


Lossy

Lossy compression will reduce the file size of a picture but by doing so will permanently delete details of the image which will reduce the quality of the image.


Lossless

Lossless compression unlike lossy compression will not permanently delete details of the image when compressing the file so details can be recovered.


JPEG

JPEG (stands for joint photographic experts group) is used for image compression. JPEG is used for compressing either 24 bit images or real life pictures.


Advantages of JPEG

It works well with photographs, naturalistic artwork and anything similar. All web browsers support JPEG.


Disadvantages of JPEG

It does not work well with lettering, cartoons, and black and white line drawings because files tend to come out very large. JPEG can only handle still pictures and cannot handle moving pictures. Has a lossy compression so some details are permanently lost when pictures are compressed. JPEG also creates a mess of vector images when they are compressed into JPEG.


GIF

GIF (stands for graphics interchange format) is a type of bitmap images. GIF is often used for simple or moving pictures.


Advantages of GIF

Suitable for logos or other simple images with solid areas of colour. GIF supports animation. Has a lossless compression so details are not permanently deleted when pictures are compressed by GIF.


Disadvantages of GIF

There is a limit of 256 colours allowed for each image. GIF is unsuitable for photographs or images with continuous colour because of its colour limit.


TIFF

TIFF (stands for tagged image file format) is a file format for storing images for Apple Macintosh computers.


Advantages of TIFF

TIFF files are usually the best quality photograph files for digital cameras. Files can either be stored as lossless or lossy files. Lossless files don’t compress the image.


Disadvantages of TIFF

Lossless files are rather big in size because of the fact that these files don’t compress the image.


PNG

PNG (stands for portable network graphics) is a type of bitmap image that was created to replace the GIF files.


Advantages of PNG

PNG compresses files into lossless images so details are not permanently lost when images are compressed into PNG images. PNG supports palette-based images and grayscale images.


Disadvantages of PNG

PNG does not support non-RGB colour spaces because it was not designed for print graphics.

BMP

BMP also known as bitmap or DIB (device-independent bitmap) is a raster graphics file format used to store digital bitmap images.


Advantages of BMP

BMP has a very realistic picture display. Image editing software will support BMP images.


Disadvantages of BMP

BMP images will lose quality when zoomed in. BMP are quite large compared to the likes of JPEG or GIF.