week 6 task file formats

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10/31/22 10/31/22 1 Week 6 Task - File Week 6 Task - File Formats Formats Philippa Rush, Jenni Philippa Rush, Jenni Chevalier, Sarah Coates Chevalier, Sarah Coates

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Page 1: Week 6 Task   File Formats

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Week 6 Task - File FormatsWeek 6 Task - File Formats

Philippa Rush, Jenni Chevalier, Philippa Rush, Jenni Chevalier, Sarah CoatesSarah Coates

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Differences between vector based Differences between vector based images and bitmap based images;images and bitmap based images;

““A vector based image uses geometrical formulas to represent images A vector based image uses geometrical formulas to represent images whereas Bitmaps (often known as raster graphics) are made up from a whereas Bitmaps (often known as raster graphics) are made up from a pattern of dots.”pattern of dots.”

Differences include…Differences include… ““Programs that allow you to create and manipulate vector grpahics are Programs that allow you to create and manipulate vector grpahics are

called called draw programmes draw programmes and programs that manipulate bit-map and programs that manipulate bit-map images are called images are called paint programs.paint programs.””

Vector graphics can be resized very easily in comparison to bitmaps.Vector graphics can be resized very easily in comparison to bitmaps. Vector images are stored in a much finer detail and therefore look Vector images are stored in a much finer detail and therefore look

better when displayed on a high resolution printer than bitmaps.better when displayed on a high resolution printer than bitmaps. Bitmaps will always look the same, regardless of printer quality.Bitmaps will always look the same, regardless of printer quality. The majority of ‘output’ devices are The majority of ‘output’ devices are raster devices raster devices as a result, all as a result, all

images must be ‘translated’ before printing.images must be ‘translated’ before printing. http://www.colourgen.com/printer_information/vector_bitmap_differenchttp://www.colourgen.com/printer_information/vector_bitmap_differenc

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Differences between GIF formatted Differences between GIF formatted file and JPEG;file and JPEG;

““GIF: GIF: Graphics Interchange Format”Graphics Interchange Format” Can only contain up to 256 coloursCan only contain up to 256 colours Optimised for contrast images and block colour, not recommended for photo’s Optimised for contrast images and block colour, not recommended for photo’s

or high definition detailed photos or imaging because photo may be notably or high definition detailed photos or imaging because photo may be notably degradeddegraded

Suitable for webpage imagingSuitable for webpage imaging ““JPEG: JPEG: The Joint Photo Expert Group image format”The Joint Photo Expert Group image format” Is usually used for photo-realistic image type, drawings and highly Is usually used for photo-realistic image type, drawings and highly

coloured/detailed workcoloured/detailed work Often compressed due to large file size, the higher the compression, the poorer Often compressed due to large file size, the higher the compression, the poorer

the image quality.the image quality. Uses knowledge of human eye quality Uses knowledge of human eye quality small loss in colour isn’t very small loss in colour isn’t very

noticeable to our sight.noticeable to our sight. Due to information loss after each saving, it is suggested that an image is only Due to information loss after each saving, it is suggested that an image is only

saved once to avoid severe degradation saved once to avoid severe degradation Suitable for webpage imagingSuitable for webpage imaging

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Difference between and embedded Difference between and embedded graphic and a linked graphicgraphic and a linked graphic

A link graphic is stored in the source file A link graphic is stored in the source file meaning that only a representation is meaning that only a representation is viewed in the documentviewed in the document

An embedded graphic on the other hand is a An embedded graphic on the other hand is a part of the document and no longer belongs part of the document and no longer belongs to the source file. This is the default setting.to the source file. This is the default setting.

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What is a 'colour palette'? What is a 'colour palette'?

A palette “is a designated subset of the total range A palette “is a designated subset of the total range of colors supported by a computer graphics of colors supported by a computer graphics system. Each color in the palette is assigned a system. Each color in the palette is assigned a number, and for each pixel, one of these numbers number, and for each pixel, one of these numbers is stored. This number determines the color of the is stored. This number determines the color of the pixel”pixel”http://en.wikipedia.org/wiki/Colour_palettehttp://en.wikipedia.org/wiki/Colour_palette

An example of a file with a small An example of a file with a small colourcolour palette palette could be a word document using black font. On could be a word document using black font. On the other hand, an image file would have a large the other hand, an image file would have a large colourcolour palette. palette.

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What is lossless compression? What is lossless compression?

Lossless data compression is a class of data Lossless data compression is a class of data compression algorithms that allows the exact compression algorithms that allows the exact original data to be reconstructed from the original data to be reconstructed from the compressed data. It is used when it is important compressed data. It is used when it is important that the original and decompressed data are to be that the original and decompressed data are to be identical. JPEG files do not usually use lossless identical. JPEG files do not usually use lossless data compression but instead use lossy data data compression but instead use lossy data compression where some visual quality is lost in compression where some visual quality is lost in the processthe process

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What does the FBS skills wiki say What does the FBS skills wiki say about using PNG files? about using PNG files?

PNG: PNG: Portable Network Graphics format. This is a Portable Network Graphics format. This is a rather new invention, designed to overcome some rather new invention, designed to overcome some of the problems described in question 2. GIF files of the problems described in question 2. GIF files are known for poor photo imaging and simplifying are known for poor photo imaging and simplifying images that contain more than 256 colours.images that contain more than 256 colours.

PNG, on the other hand, provides a much higher PNG, on the other hand, provides a much higher colour support and a slightly better compression colour support and a slightly better compression quality. This is used fully across the worldwide quality. This is used fully across the worldwide web, but things are always developinh.web, but things are always developinh.

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What is BAD about using .bmp What is BAD about using .bmp format files in your work? format files in your work?

they are not supported by any web browsers they are not supported by any web browsers therefore they are not a suitable format for therefore they are not a suitable format for images in a web applicationimages in a web application

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What is Flickr? What is Flickr?

Flickr is a photo sharing website, mainly used by Flickr is a photo sharing website, mainly used by bloggers. The purpose of Flickr is to “get photos bloggers. The purpose of Flickr is to “get photos into and out of the system in as many ways as we into and out of the system in as many ways as we can get photos from the web, from mobile devices, can get photos from the web, from mobile devices, from the users' home computers.” It also allows from the users' home computers.” It also allows innovative ways to organise photos. Although innovative ways to organise photos. Although Flickr is mainly for recreational purposes, photos Flickr is mainly for recreational purposes, photos can be downloaded from the site and may be used can be downloaded from the site and may be used in presentations. in presentations.

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