File Format ResearchVector Graphics (geometric modelling, Object-oriented graphics)

Vector images are similar to jpegs and bitmaps but they are different and much more useful because vector images can be stretched and twisted and the stays the same. Vector images can also be edited alot more for example. the detail of the images can be removed to make an images for a leaflet or sign. Vector images are different to raster images because they record points on the entire picture just like star constellations and this means that the images can be remembered. They are remembered because of lots of mathematical equations

Raster Images

Raster images are usually made a very a large group of rectangles called pixels each of these pixels have a colour this makes up the picture and how the picture is coloured and looks. Unlike vector images when raster images are stretched the squares become bigger and because further squares are not added the images becomes very very blocky giving the picture less definition therefore ruining the picture .On the other hand raster images are very small in size compared to vectors so you sacrifice quality for quantity. As you can store more raster images then vectors this means raster images are more practical in everyday use than vectors but vectors have better quality overall. So in summary raster images should be used for everyday purpose and vector images should be used for the specialist jobs like graphic design for websites or concept art for games.

Bitmap

 Bitmaps are images that are based on lots of small squares know as pixels. Every single pixel has a different colour and place given to it.  A disadvantage of bitmaps is that when you resize the images to look bigger or smaller they become distorted and look blurry ruining the picture your trying to edit Bitmaps can be used for artwork in painting programs and photos You need to choose the operation system when you save bitmaps like windows or  OS/2Also these files can only go up to 32 bits in the colours range

 Vector

 Vector graphics look good at any size so you can rescale them to any size and they will end up looking like the original picture, so these are good for logos or maps as well as being better to resize vector graphics are smaller in size than gifs meaning they take up less space and can be downloaded faster

 MPEG 

  Mpeg stands for moving pictures experts group, This is also refers to the family of digital video compression standards and also the file compressed done by this group MPEG is able to get a high compression rate because it only stores the changes from one frame instead of each other frameThis is very very good because the space is so small you can store many many mpegs on your computer it is also a lot easier to share the files with your friends or add them to a personal website on the internet Overall it’s the most useful if you want to show quick funny video you have made to you friend over msn and have a laugh  

Photoshop .psd .pdd

 This is the default save file format for Photoshop, these files may be big because they contain all the information about the layers channels and effects so that people can edit the picture more.The files can then be saved as a different format like a gif or an mpeg this reduces the size of the fileThe main purpose of this file is so that you can go back to your image and continue to edit it from where you left off Like in collage you doing images for your website and don’t get it finished in time you can save it and edit it tomorrow or when ever you like The bad thing about these files is that if you’re doing a lot of editing the file becomes bigger and takes up a lot more space so if you edit a lot it will take up all your space The great thing about these files is that you can come back and edit your files and take your canvas with you on a usb or a hard drive Also the ability to make your image into a vector or lots of other different file formats is very handy alsoLarge Document Format .psbPsb files are only used in Photoshop cs and cs2. this file holds documents of 300,00 pixels so it if very good for when your working with a large file

   CompuServe GIF .gif 

The gif is the most common type of file format found today most images that are on the internet are gifs This is because of the small’s size and acceptable quality The bad thing about gifs are that if you resize the gif to a bigger size that it originally was the picture will be distorted and hard to find out what it is Gifs are the most practically for everyday use because of its small size so it means that more of them can be store don peoples computers and easily uploaded onto the internet GIF stands for graphic interchange format and was made to compress images.This format is used a lot on the internet GIFS can be used to make small animations like flipbooks Gif pictures can have up to 256 bits  

Photoshop EPS .esp 

 As well as a shorted version for Spain (espanyol)  Esp files are used for when images are to be imported into other programs like PageMaker or Quarkxpress Also esp is used for printed images and CMYK mode As well as all that esp allows you to save paths but sadly not alpha channels 

Print 

All esp files are used in print because they have a vector format. This is because they look good in any resolution for any printerIt is made thinking about the print colour space The bad thing with these files is is that it looks really bad on the screen because it uses a very low resolution and bad colouring but when it is changed to a postscript printer it looks great 

Changing of the file formats

 Mostly every graphic on the internet today are bitmaps like gifs and jpegs but there is an increase of vectors for people website logos and pictures they have drawn like art and animations A while ago the only vectors used on the internet where in flash but now there are others coming out that use vectors like SVG This lets web site designers use vectors which will make there graphics look amazing this has increased the quality of the websites on the internet today 

File Formats And Colour

 Different images file formats can have lots of different colours Each file format will have its own bits per pixel that it can support 1 bit per pixel refers to an image with 2 colours 4 bits per pixel refers to an image with up to 16 colours 8 bits per pixel refers to an image with up to 256 colours 16 bits per pixel refers to an image with up to 32, 768 colours 24 bits per pixel refers to an image with up to 16, 777, 216 colourssssss

Bit Depth

a bit is the smallest unit used for measuring on computer information. each bit can either be a 1 or a 0 (off or on) Bit Depth is used for the number of  colours that can be shown on the computer. ther bigger the bit depth the more colours can be displayed in the picture.this increases the files size

 

Bit Depth	Formula	Number of Colors
1-bit	21	2
2-bit	22	4
3-bit	23	8
4-bit	24	16
5-bit	25	32
6-bit	26	64
7-bit	27	128
8-bit	28	256
24-bit	224	16,777,216

Graph Taken from

http://www.adobe.com/education/instruction/webtech/CS2/unit_graphics1/gb_print.html.

Colour Space

Grayscale:

Grayscale is when you change all the colours in your picture to gray, everything is changed into black white and gray.

grayscale picture are very different to just black and white pictures because when its black and white, black and white are the only colours in the picture but garyscales adds gray giving the image a bigger range of colours.

RGB

RGB

 simple stands for red green and blue. RGB is when the lights of all three colours gets combined and make alot of various colours, RGB is used for televisions

YUV