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Systems Assesment Task

In Uncategorized on April 29, 2013 at 11:24 am

Image

This image is saved as a PNG at the size of 65.8 KB.

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This image is saved as a JPEG at a size of 38.3 KB.

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This image is saved as a GIF at a size of 19.7 KB

The image difference is hard to spot since it is all in one colour but when zoomed in all 3 become very pixelated and the GIF more than the others as it uses lossy compression to reduce the file size rapidly and also only holds 256 colours to be used.

As you can see the image saved in PNG is much darker than the others.

PNG is the default image type to stream over the internet replacing GIF because the PNG compresses images better than GIF and it can also hold more colours making it better quality.

GIF is a compression type that uses loseless commpression to decrease the file size. IF also supports transparency, where the background color can be set to transparent in order to let the color on the underlying Web page to show through.

JPEG is a compression type that uses lossless. The information that is discarded in the compression is information that the human eye cannot detect.JPG images support 16 million colors and are best suited for photographs and complex graphics.

wireless communications

In Uncategorized on April 23, 2013 at 9:34 am

bluetooth vs wifi

bluetooth transfer speed: 2.1mbps

wifi transfer speed: 600mbps

devices that use bluetooth: mobile phones, computers, smart tv’s, ipods, stereos, wireless earphones,mouse

Devices that use wifi: tv’s, computers, cars, phones, ipods, personal stereos, servers, notebooks

Firwire vs usb

Transfer speed of firewire: 800mbps

Transfer speed of usb: 480mbps

Devices that use firewire: computers, laptops

Devices that use usb: mobile phones, tv’s, digital cameras, desktops, laptops, game consoles

magnetic storage

typical hard disk memory: 8GB

typical extrenal hard drive memory: 500GB

Video storage for 8GB at 1080p: 2 hours

Video storage for 500gb at 1080p: 475 movies

music storage for 8GB at 4mb: 2000

music storage for 500GB at 4mb: 25000

optical storage

A CD- ROM can usually hold around 80 minutes of music.

Normal DVD’s hold around 2 hours of video

Blu ray can usually hold about 25 GB

Holographic Storage

When the blue-green argon laser is fired, a beam splitter creates two beams. One beam, called the object or signal beam, will go straight, bounce off one mirror and travel through a spatial-light modulator (SLM). An SLM is a (LCD) that shows pages of raw binary data as clear and dark boxes. The information from the page of binary code is carried by the signal beam around to the light-sensitive lithium-niobate crystal. Some systems use a photopolymer in place of the crystal. A second beam, called the reference beam, shoots out the side of the beam splitter and takes a separate path to the crystal. When the two beams meet, the interference pattern that is created stores the data carried by the signal beam in a specific area in the crystal — the data is stored as a hologram.

It also may hold around 25 terabytes.

 

online storage

cloud storage is saving your work over the internet and saved onto a server which means it will take up no memory in your computer.

cloud storage can hold around 13GB

the advantages of  cloud storage is that it wont take up any memory in your computer, its cheap and doesnt require any installation.

the disadvantages are that the company who holds the data may go under, the account could get hacked and back ups can be slow due to your internet connection.

 

regular desktop vs multimedia computer

A huge difference is between the graphics card and this is because the graphics card in a multimedia computer has to deal with higher quality graphics resulting in it requiring a much better and more expensive graphics card.

The processor also has to be alot faster in a multimedia computer to compensate for the many tasks it must execute which means it will be alot more expensive and a higher quality.

 

Display

A flexible display is TFT backplates with olymer and metal-foil substrates together that makes a clear display like glass.

3D has a high impact on on multimedia as it is becoming increasingly popular with movies and games.

vector graphics

In Uncategorized on April 10, 2013 at 1:23 pm

Vector graphics are a collection on objects and paths, these objects and paths contain attributes which makes up the objects. Since these images are only made up of objects the file sizes are alot less than bit mapped graphics. This means vector graphics cannot be used for photographs but bit mapped graphics. When zooming in on a vector works graphic the image the image does not become pixilated unlike bit mapped graphics because the image repositions itself to allow zooming in without loosing quality because vector graphics are not made up of a number of dots, they can be scaled to a larger size and not lose any image quality.

in terms of file sizes bitmapped graphics are much larger than vector graphics as it must save all pixels in the image and the bit depth of each colour where as the vector image only holds the coordinates of the image, the amount of objects, the colour of the object and the line thickness.

Vector graphics are also not resolution dependant which means it does not print at the screen resolution so it can print at a much higher quality.

Some of  the vector graphics software packages are: vector graphics, serif draw plus, inkscape and Adobe Illustrator.

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