In order to create and use the graphics seen on websites, flyers, newsletters and such, there has to be a file format able to save and process the initial graphic before it is put on media. Most graphic designers use Adobe Illustrator for their work as Illustrator uses vector images and look neater with logos, however, some prefer raster images and use Photoshop as this can be suitable for working with photographs.
There are different graphics file formats with uses that suit different needs i.e. for web-based graphics a designer would use PNG as it is a lossless compression file format (which means it doesn’t lose any information within the picture) or for working with photographs, the designer would use jpeg because it is of lossy compression (which means it will get rid of any unnecessary data in order to make the file smaller).
After a lot of researching, I have found the main file formats used in graphics design. I will cover the uses and importance of these file formats within the newsletter – the file formats used for graphics include JPG, PNG, TIFF, GIF, BMP, SVG, CGM, PSD and AI.
WHAT FILE FORMATS ARE USUALLY FOUND IN DIGITAL GRAPHICS?
I have researched the different Digital Graphics that can be used and have found the following:
- JPEG can be used for web-based graphics as they are a smaller file size and therefore do not take as long to render. These are of lossy compression and therefore have quite a lower quality – most cameras save in the jpeg format which can be an issue as every time a jpeg is saved or edited, it loses more and more quality and can be seen as a photocopy of a photocopy of a photocopy.
- TIFF formats save 8 bit or 16 bits per colour. They are more used with photographs when printing as it picks up colours with more focus and therefore works better than other formats.
- RAW formats are used in digital cameras which use lossless compression so the file size is heavily reduced.
- GIF formats support animation but give a low quality image. Only little data is lost and therefore they are a lossless compression.
- BMP files are very large and uncompressed – they can usually be found within Microsoft Windows.
- PNG are the most used for graphics work and as they work the best for online and displaying images.
- PSD is the Photoshop format used for raster graphics – they work better for in-progress photographs that still need to be edited as they remain high quality. Raster formats usually suffer when scaling upwards, as it will lose quality, however, they are usually okay to be scaled downwards.
- Vector formats allow you to scale an image or piece of work up and down without losing any quality and therefore are used best when it comes to printing.
WHAT ARE VECTOR GRAPHICS?
Vector graphics consist of geometrical connected lines and curves that produce objects by going through control points which have a definite position on the x and y axis and can determine the structure of the path. Vectors can be zoomed in and out of without changing the picture and there is no loss of quality.
Vector graphics are more commonly used for graphic work, i.e. logos because they do not lose quality when they are scaled. They are also able to allow the graphics designer to alter colours and different aspects of part of the design without changing the entire design or corrupting it. Regardless of if the vector graphic itself is large, the file size remains small.
Examples of vector based programs could be Adobe Illustrator, Inkscape or CoreiDraw.
WHAT ARE RASTER (OR BITMAP) GRAPHICS?
Raster art is a digital art that is made of horizontal or vertical rows of pixels. Raster images are more commonly known as bitmap images. Each pixel inside of the bitmap image is scanned and the collection of pixels is called a raster image. Scanned and web graphics (JPEG and GIF) are the most common forms of raster images. Most computer images are stored in raster formats, JPEG, GIF and PNG, which are popular online and raster formats are better than vector formats for handling photographs and photo realistic images. There are many raster based image editors for example, MS Paint and Photoshop. However, if enlarged the image quality will fall dramatically and raster graphics are dependent on resolution even though, scaled downwards doesn’t change anything yet scaled up makes the image look blocky and may be unavoidable.
WHAT IS COMPRESSION?
To store image files, you will have to use one of three different compression types. Depending on what you plan on using your graphic for will determine which type of compression you will use.
You will either use a compressed format, an uncompressed format or a vector format.
There are two types of compression that you can use which will either reduce the quality but make the file size smaller or one that only reduces the file size by 50% so it does not lose quality. These are known as lossy and lossless compression formats. Lossless is most used for compressing data and programs as the quality cannot be lost, however, the 50% reduced file size is usually needed whereas lossy is commonly used to graphics, audio and video where the quality loss may not be as noticeable but they will need a smaller file size as they may be being used for things like web so they will need a smaller file size in order to render faster.
WHAT ARE METAFILES?
Metafiles are files that can be transferred easily and allow you to exchange data through different softwares. They are a combination of both raster and vector files are are therefore able to be opened in almost all photo editing software. Metafiles are good for web transfer as they are often smaller in size and easy to render.
An example of a metafile is a PDF – PDF’s are useful and use a combination of both raster and vector formats and can give a high quality print result, although PDF’s are not the ideal type you shall use for graphics.