Types and Uses of File Formats

Bitmap

Features

Bitmap graphics are also known as raster graphics. This file format is most commonly used on the web and on computers. Bitmap graphics are made up of pixels which specify what colours will be created. An image could contain hundreds of thousands of pixels. An advantage of a bitmap graphic would be that the graphic is displayed realistically. Another advantage would be that bitmap images are very easy to modify.

Limitations

One of the main disadvantages of bitmap graphics is that they don’t scale very well and the picture quality decreases once the image is enlarged. Bitmap files are also a large file type when saved to the disk and the higher the quality of image the larger the file size.

This is an example of a bitmap image that has been enlarged.

Vector

Features

A vector graphic is made up of lines, points and curves to create complex objects. Vector graphics are created through a series of mathematical calculations and this allows the graphic to be re-sized without losing any of its quality. Another positive feature of vector graphics is that they don’t take up much disk space when saved to a hard disk.

Limitations

Vector graphics use up a lot of the computer’s memory and this means that it could take longer to show up on the screen. Another limitation of vector graphics would be that they don’t appear to look as realistic as bitmap images and that’s why they are not a good choice for displaying photographs.

This is an example of a vector image and as you can see the image does not look very realistic.

JPEG

Features

JPEG (Joint Photographic Experts Group) is a method of compressing photograph images. JPEG is used to compress full-colour (24 bit) or grey-scale digital images of “neutral” (real world) scenes. JPEG is most commonly used to compress and store images on a web page. An advantage of a JPEG file is that it can manage many colours aswell as keeping the file size as small as possible. Most good websites support JPEG.

Limitations

Due to the lossy algorithm that JPEG files use you will lose some of the detail when converting different formats into JPEG. The edges of lines of a vector image may get blurred out when using JPEG.

GIF

Features

GIF (Graphics Interchange Format) is a bitmap image format. This format is one of most widely used on the web. GIF supports up to 8 bits per pixel which allows a single image to reference a palette of up to 256 different distinct colours. GIF images can have transparency for use over a website. Their file size in generally small and you would be able to view and download them quite quickly.

Limitations

The quality of the image may decrease if you are using too many colours as GIF files have a 256 colour limit.

Below is the same image saved in different file formats and this has resulted in the size of the files varying.

BMP – 29,404 KB

This image has been saved through Adobe Photoshop and has a relatively large file size.

JPEG – 561 KB

This file size is smaller than the others which means that it could be downloaded and viewed quicker.

PNG – 5695 KB

This file type was designed for transferring images on to the web so the file type would be quite small for quick transfer rates.

This file format uses no compression at all therefore resulting in a large file size.

File Format Compression Techniques

File compression is reducing the size of a file in order to save disk space or for quicker transfer rates. There are a few different file format compression techniques.

Lossy Compression

Lossy Compression is when some data is lost to enable the file size to be reduced dramatically. Lossy compression is most commonly used to compress multimedia data such as video, audio and images. Lossy compression reduces the file size a lot more than lossless compression would.

Lossless Compression

Lossless compression is when you extract the exact original data from the compressed file without losing any of its contents. Lossless compression is very popular in zip files and you would have to use a program such as WinZip to extract the data from the compressed file.

This image is comparing the difference between lossy compression and lossless compression. It shows us that the lossy compressed file is smaller than the lossless compressed file but when they are both restored the lossy compressed file loses some of its data whereas the lossless compressed file doesn't.

This image is what the program WinZip looks like. Using this program you select which file you would like to extract on to your computer and where you would like to save it.

Resolution and Colour Depth

Resolution

Image resolution can also be known as dpi (dots per inch) or ppi (pixels per inch). Image resolution describes the detail of an image and the number of pixels that it can contain. The more pixels in an image, the better the quality but it might also increase the file size. An image that is enlarged will lose its quality if it is created by pixels.

This is what happens when a graphic that is created by pixels is enlarged. It becomes pixelated and loses its quality.

Colour Depth

Colour depth or bit depth is used to describe the maximum amount of colours that are used within an image. Bit depth is used to describe the colour of a single pixel and each pixel is represented by one 8-bit byte. The 8 bits are divided up between red, green and blue, normally three bits for red, three bits for green and two bits for blue.

New and Emerging Technologies

iPad 2

The iPad 2 is a computer tablet created by Apple. The iPad 2 is the second generation of this device. It allows you to download applications in the same way as the iPhone. The iPad 2 is much thinner and has a better overall performance than the iPad.

 Here are some of the new key features of the iPad 2:

·     Front and Rear Camera – One of the applications called FaceTime allows you to have video calls with anyone who has an iPhone 4 or Mac with FaceTime.

·     Graphics Performance – The graphics performance on the iPad 2 is nine times better than that of the iPad.

·      Thinner and lighter – The iPad 2 is 33 percent per cent thinner and up to 15 per cent lighter than the iPad. This makes it more portable and easier to store away.

·      Choice of Colour – The iPad 2 is now available in white as well as black.

·     Storage – The iPad 2 now comes with up to 64GB of storage.

The iPad 2 is a great device for manipulating digital graphics especially with the increased performance of the graphics within the tablet. There are many applications that you can download which allows you to change digital graphics. There is an application called iMovie which is a video editing tool. This tool is designed for the Multi-Touch screen and it allows you to add videos, photos, music and sound effects. You are also able to take your own pictures and edit them in whatever way you want using an application that allows you to manipulate digital graphics

Xbox Kinect

The Xbox Kinect is an accessory that you can purchase for the Xbox that works as a motion sensor. Unlike then Nitendo Wii and Playstation Move there is no controller and the Kinect relies solely on body movements. You can play many different types of games such as bowling, golf, boxing and tennis and you have to make the same movements as you would if you were playing those sports for real. It is a very good past time and a great form of exercise. The price of the Xbox Kinect sensor is about £90.

iPhone 4S

The iphone 4S is the latest release in the iphone series. The iphone 4S is an all round better phone than the iPhone 4. There a new features such as Siri, FaceTime, Retina Display and iCloud. There are also a lot of performance improvements such as the new A5 processor, 8 megapixel camera and 1080p HD videos.

• Siri is a program within an iPhone 4S which allows you to use your phone by talking to it. Siri will send a text for you, make a phone call for you, tell you the weather, tell you where the nearest ATM machine is and will do many more things. Siri not only understands what you say, it knows what you mean.

• FaceTime is like a video call and it allows you to see the person you are speaking to on your screen. Facetime will only work with another iPhone or iPad device that supports the application. You can also use FaceTime on an Apple Mac using WI-FI.

• Retina Display is the highest resolution phone screen ever. The pixel density is so high that the human eye is unable to make out individual pixels. This means that the iPhone 4S is a great device for watching movies, taking videos and taking pictures.

• iCloud acts as a storage device and allows you to store up to 5GB worth of data such as photos, music, applications and contacts. 

Roll Laptop

• The Roll Laptop has a flexible OLED screen and a roll-able keyboard. 

• The straps connected to the laptop double up as USB outlets.

• The cooling system takes cold air in from the right hand side and releases the hot air from the left. The Roll Laptop has been designed this way to make sure it doesn't overheat and damage any of the hardware components within.

• The Roll Laptop has a mouse and webcam included that you can attach to your wrist.

• One of the main advantages of being able to roll up your laptop is that it will become more portable and take up less space.

Software and Hardware

Two types of software that can be used for digital graphics are Adobe Photoshop and Sumo Paint.

Adobe Photoshop

Adobe Photoshop is one of the most popular digital graphic manipulation software. It has many features such as adding layers, image size alteration, cropping and selective colour changing. 

Using layers allows you work on two different parts of the image separately so that you can bring them together at the end.  

Image size alteration allows you to edit the size of the image you a working on.

Cropping allows you to delete a selected part of the image.

Selective colour changing allows you to change the colour of certain parts of your image.

There are many different tools that you can use in adobe Photoshop.

Brush Tool

The brush tool allows you to paint your image in which ever colour you want.

Eraser Tool

This tool allows you to delete a selected part of your image. It works in the same way as the brush as you have to click and drag over the picture.

Move Tool

The move tool allows you to move objects.

Measure Tool

This tool enables you to measure length, width and locations of your image.

Healing Tool

This tool allows you to repair damaged looking parts of the image.

Limitations of Adobe Photoshop

·         Photoshop is a very expensive piece of software.

·         It also contains many features which means that it’s very difficult the learn them all. It will take a lot of                training and experience to be able to use Photoshop to its maximum capacity.

·        Another limitation is that Photoshop is a large file and it also uses up a lot of the computers memory.

Sumo Paint

Sumo Paint is an online image editor.

Sumo Paint is similar to Adobe Photoshop in the way that you can manipulate digital graphics. Sumo Paint also allows you to use features such as cropping and adding layers.

Sumo Paint contains tools such as the ink brush tool, smudge tool, shapes tool and gravity.

Ink Brush Tool

This tool allows you to create realistic ink impressions.

Smudge Tool

This tool has a big selection of brushes and the possibility of using the following blending modes: Normal, lighten and darken.

Shapes Tool

This tool allows you to add a wide selection of shapes.

Gravity

The gravity tool smooths the drawn line to curves.

Limitations of Sumo Paint

A limitation of Sumo Paint is that if you don’t have internet access you are unable to use it.

This piece of software cannot be downloaded on to your computer.

Also if you don’t have a Sumo Paint account you cannot save your work.                                                                   

Digital Camera

A digital camera is a piece of hardware that stores pictures in a digital format. The following digital camera is a Nikon 3100:

Key features of the Nikon 3100:

Refined guide mode for ease of use.

14.2 megapixel DX-format CMOS image sensor which delivers beautiful photos and prints well beyond 20x30 inches.

Full 1080p HD cinematic video with full time autofocus and sound. This allows you to record movies in full 1080p HD quality. 

Fast 11-point autofocus system which delivered razor sharp pictures.

Built- in HDMI port. 

Compact and lightweight design.

Limitation of the Nikon 3100

There had been issues with the continuous autofocus.

This digital camera is very expensive. Prices can vary between £350 and £600.

Quality of the LCD is not great.

USB and A/V cables not included.

Scanner

A scanner is a piece of hardware that allows you change a photograph into a digital image on your computer. The following scanner is a CanonScan LiDE 210 Flatbed scanner:

Key features of the Canon CanoScan LiDE 210 Flatbed scanner:

Optical Resolution is 4800 dpi x 4800 dpi.

Maximum document size 216mm x 297mm.

Hi-Speed USB. 

Auto document fix.

You are able to scan, copy and e-mail.

Limitations of Canon CanoScan LiDE 210 Flatbed scanner

The lid can only be raised a small amount

A limited amount of features on the software included

OCR (optical character recognition) only works with notepad.

Performance Of A Computer System

Hard Drive

The hard drive is where all of your programs and files are stored.

The data on the hard drive can be erased or overwritten.A clean surface area is critical to the proper functioning of the hard disk.

The faster RPM (Resource Package Manager) hard drive will give you faster response times when the computer is moving data from storage to use.

You can use a hard drive to manipulate digitals graphics as you are able to save your pictures.

Graphics Card

A graphics card is a piece of hardware that is installed in the computer that is responsible for rendering the image on the display screen.

Gamers will often upgrade their graphics card for a better gaming experience.

The better the graphics card, the better the display of the digital graphic.

Processor

The processor is the brain of the computer.

It tells the computer what to do and when to do it.

Processor speed is measured in MHz(Megahertz) or GHz(Gigahertz).

You can also have up to four processors in a computer(quad core).

The more GHZ, the better the performance. With a better processor you can use photoshop and any other digital graphic software more efficiently.

RAM

Random Access Memory provided space for your computer read and write the data to be accessed by the CPU.

RAM is volatile which means its contents are lost when the computer is turned off.

The more RAM you have installed in your computer, the better the performance.

Having more RAM will let you manipulate digital graphics a lot quicker and easier.

Hardware Components

Mouse

A mouse is a pointing device. You can move it round the screen and click icons. It has a scroller ball which you can move pages up and down. There is a left click and a right click that have different functions.

You can use a mouse to manipulate a digital graphic by resizing and cropping images. You can also use a mouse to add different effects.

Screen

A screen is used to display the images and writing. It also shows it in colour.

You can get different screen resolutions and you can adjust the screen to how it suits you.

You can use a monitor to manipulate digital graphics as it displays all your work in a high resolution.

Graphics Tablet

A graphics tablet is a hardware device that contains a stylus. Whatever you draw on the graphics tablets appears on the screen.

A graphics tablet can used to manipulate a digital graphic as you can draw your own images and edit them.

Digital Camera

It is used to take pictures that can be uploaded on to the computer.

It stores the photographs in a digital format.

You then edit pictures in whatever way you want.

Scanner

A scanner is used to change a photograph into a digital image on your computer.

A scanners quality is measured by how many dots per inch it recognises (DPI).

When the image is on your computer you are able to edit it.

The following link explains how to use a scanner: http://www.youtube.com/watch?v=bhd1kU5yIZQ



Flash Card

A flash card is a storage device that holds data.

They are most common in mobile phones, laptops and digital cameras.

It can be used to manipulate digital graphics as you are able to transfer images to different computers using
the flash card.

USB

A USB pen is also a storage device that holds pictures, music, videos and documents.

USB pens are mainly used in computers but can also be used to transfer data to televisions.

USB pens are used to manipulate digital graphics as you are able to transfer data to different computers.

Firewire

Firewire is a high-speed data serial bus.

It can move data up to 400 Mbps.

Firewire can be used to manipulate digital graphics as you can transfer data at a high speed.

Printer

A printer is an output device that prints text or illustrations on paper.

There are different types of printers such as laser, ink-jet and LED.

Printers can be used to manipulate digital graphics as you are able to print out your image that you have changed from your computer.