File Formats and Applications Report

File Formats and Applications Report

There are many different types of file formats used in graphics, and each one stores information differently. The two most common file formats are bitmap and vector. In this report I will be discussing the main file formats and applications (software) used in the media industry today. Programmes such as adobe Photoshop(.PSD) use bitmap file formats, whilst Illustrator(.AI) and InDesign (. INDB) use vector file formats.

Vectors

Vectors are used to create text and simple logos, and don’t take up a lot of storage space at all.  Vectors are made from shapes and lines, and use mathematical algorithms. Vectors are completely computer generated, which means that they are just computer generated drawings. An advantage of using vectors is that they are not made of pixels, so images can be enlarged as many times as you want, without losing quality. They are actually made up of co-ordinates, shapes, lines and colour data. A vector file is also easier to edit as work can be stopped and continued at any time, and they have crisp and sharp edges. However, because they are made up of shapes images that are produced do not look realistic and are very time consuming to create. Vectors are also smaller in file size, compared to bitmap, however they are not supported on the internet. To be able to have a vector image on a webpage, it is best to rasterize it, which means that it will be converted to bitmap. However, this could mean that the edges of vector graphics lose definition and become pixelated. Vectors use other file formats also, such as .AI, .EPS, AND .PDF.

Bitmap

Bitmaps, also known as raster graphics, are used to create photo-realistic images and graphics. They consist of loads of pixels, which look like small rectangles when displayed on a monitor, and merge together when looked at from a suitable distance.  The more bits per pixel the higher quality the image will be; however, this will also increase the size of the file. The range of the bit depth available depends on both the graphics card, and the software being used. Bitmap images are dependent on the resolution of the image. For example, if the resolution of the image is too low, the pixels will more than likely become evident, and the quality will be terrible. This is also known as pixilation, which can also happen if the image has been enlarged too much. When the edges of shapes become jagged, the process is called jaggies. This is when both text and shapes become bumpy lines that should be smooth. Jaggies occur when the monitor or printer doesn’t have a high enough resolution to ensure that the image will have smooth lines. Anti-aliasing is a technique used in software’s to get rid of jaggies. Anti-aliasing reduces how prominent jaggies are by surrounding the jagged lines with shades of gray (on a gray-scaling device) or colour (for colour devices).

Applications

 Adobe Photoshop

Adobe Photoshop is a bitmap programme. Photoshop is based on pixels which are small square colours.  A disadvantage of Photoshop is that you have to be careful when making the original image so that when you enlarge it to print, it doesn’t pixelate. Photoshop differs from paint in that it has layers, filters and editing tools. Layers allow you to collage images together to create artistic imagery. One such feature is Layer Mask, here you can erase part of an image, but not permanently.  It can be found under Layer>Layer Mask>Reveal All.  This makes erasing more flexible and the image can be brought back again. An advantage of Photoshop is that you can manipulate photographs that might have blemishes. The disadvantage of Photoshop is that it creates very big file sizes and can make it difficult to email to someone.

 Adobe Illustrator

Adobe illustrator is a vector programme. Illustrator is based on shapes, lines and mathematical algorithms, and because of this, it makes it possible to scale an image to any size, without losing resolution or quality. Illustrator is best used to create simple logos and detailed cartoon pictures. It also has a good variety of tools to paint and draw with, and also gives the user steady control over typography and manipulation. A disadvantage of using illustrator is that takes a long time to create a photo-realistic image because of the amount of layers needed.

InDesign

InDesign is primarily a layout programme that relies on Photoshop and illustrator for the imagery. The main advantage of InDesign is that it has multiple layers. If you were creating a 50-page brochure you would not use Photoshop, as it only allows one page at a time. You would use InDesign because of its multiple pages. This is a vector programme, so you cannot manipulate images, it is purely a layout programme.

File Formats

JPEG(.jpg) is developed by the joint photographic expert group, and is the most used, and recognized bitmap file format. JPEG is applied for the processing and storing of full-colour images with very realistic elements, brightness and colour transitions, and is strictly a bitmap file format. JPEG is the most convenient file format, as it takes up the least amount of space in comparison to other file formats. An advantage of using .jpeg is that you can compress the file easily, however, this uses lossy which means that when the file gets compressed it isn’t the same as the original.

.TIFF stands for tagged image file format and is a file format that is used strictly for bitmap data. This means that it doesn’t handle text or vector data. It’s a flexible format which is supported by a range of different image processing applications and most software available. The file extension is .TIF, even though it is most commonly known as .TIFF. TIFF images use tags, which are keywords to define characteristics of images, that are included in their file.  An advantage of using .TIFF is that it is widely used, which means that it can be edited very easily with any editing software available and can also be opened by anyone who receives it, as all well-known systems have .TIFF viewers built-in.  TIFF files do have compression, but is fully restored when opened. This is also an advantage as no detail will be lost when the image is saved.  This is good because the file can be saved frequently, and no information will be lost.  Since compression isn’t a default setting on .TIFF files, the file size is usually very large (.TIFF is the largest file format). This is a disadvantage, as .TIFF files take a lot more room than .JPEG files.

 .GIF stands for graphics interchange format, and is strictly a bitmap file format. .GIF is used for animations and is very easily created using certain animation software. Gifs use lossless compression, so no data is lost when the size of the file gets reduced, but generally speaking GIFs tend to have a small file size. They are also very easy to access as they are supported by all browsers. The disadvantage of using .GIF file formats is that they have a maximum colour depth of 265 bit, however this is normally suited for most web pages. Most GIFS usually have a pixelated appearance which reduces the overall quality of the animation. Dithering is used to prevent a harsh colour contrast, however this restricts how much compression of the file can take place. Dithering is used to reduce colour by adjusting the value of adjacent pixels to create the effect of smaller values, but sometimes dithered images can look very grainy, so you have to be careful. Another disadvantage of using GIFs is that when they are used on webpages, they can sometimes slow the webpage that you are browsing down. This is why GIFs are optimized. This is when files for images are converted into a type that can be viewed on a webpage. It reduces the size of an image so it can be downloaded as part of a webpage easily.

.PNG stands for portable network graphics and is also a bitmap file format. .PNG is an alternative to .GIF file formats, as it has a smaller file size and uses a colour index, which is a set palette of colours.  .PNG also supports more colours than .GIF file formats, including 24 bit and 48 bit colours. .PNG also uses lossless compression so no data from the file is lost.

Applications

.AI is a file format that stands for Adobe Illustrator which is a software program that you can create vector drawings in.Illustrator is based on a mathematical algorithm drawing shapes and lines. This makes the file small, as it does not rely on pixels. It is used to create digital graphics such as logos. The file is generally saved as an .AI when the drawing has not been completed and still needs to be finished. When the drawing is completed it is generally saved as an .EPS. The advantages of vectors is that work can be stopped and continued at any time and is easy to undo and restored back to its original image.

Algorithm is a set of instructions designed to perform a specific task. In computer programming, algorithms are often created as functions. These functions serve as small programs that can be referenced by a larger program. For example, an image viewing application may include a library of functions that each use a custom algorithm to render different image file formats. It is a process or a set of instructions to be followed using mathematical calculations or other problem solving operations..PDF stands for portable document format and can be either a vector or a bitmap file. A .PDF file would not really be seen on a website but will be offered a downloadable file that can be read on any .PDF reader. To see if an image is a vector or bitmap on a .PDF file you can zoom in and see if the image pixelates. If the image does not pixelate the image is most likely going a vector. (See source three for an example). This type of file can be used to send artwork ready files to reprographics houses as they incorporate fonts and images.

.EPS stands for encapsulated postscript which is a standard graphics file format that allows you to exchange images, drawings (logos or maps), and even layouts of complete pages. It can include both bitmap and vector data. .EPS files can be anything from text, to graphics and images, and is usually saved as .EPS when the final work is finished. The file is good for exchanging an presenting. Vector and bitmap images have distinct differences, and both have their advantages and disadvantages. Which format is better however, is completely based upon what you need to do, and what look you want your final image to have.