Graphic Formats:

 

1. Write a paragraph explaining the difference between raster (bitmap) graphics and vector graphics.  Discuss the advantages and disadvantage of each.

Bitmap graphics are far more detailed and take up much more space for the most part than Vector graphics do. Bitmaps are essentially large "maps" of a huge number of small dots that are minimized to make the images teh way they are. By doing this and then with the nunmber of dots it can really make an image large, where as with a vector image that uses a intercollection of points and lines to make images, this also helps to make them smaller and more user friendly space wise. Also when an image is zoomed in, bitmaps become grainy, where as vectors are still sharpe and easy to see.

 

2. Define bit depth and color depth.  How are these related to gifs, pngs, and jpegs?  Create a table illustrating the various colors found at 1, 4, 8, 16, and 24 bits.

Bit depth is the number of bits in each pixel where as color depth is the max number of colors in an image and the bit depth of the display monitor. Something important to remember is that depending on the bit depth and the color depth, will effect whatk ind of gif, png, or jpg image you will get. What I mean by that is that is for example, a GIF can't have more than 256 colors, where as a JPG can only have over that number of colors.

Bit Depth Color Resolution Calculation
1 bit 2 colors 21 (2)
2 bit 4 colors 22 (2x2)
3 bit 8 colors 23 (2x2x2)
4 bit 16 colors 24 (2x2x2x2)
5 bit 32 colors 25 (2x2x2x2x2)
6 bit 64 colors 26 (2x2x2x2x2x2)
7 bit 128 colors 27 (2x2x2x2x2x2x2)
8 bits 256 colors 28 (2x2x2x2x2x2x2x2)
16 bits 65,536 colors 216
24 bits 16,777,215 colors 224

 

3. Define "interlacing" and the advantages and disadvantages and when it should be used.

Interlacing images essentialy is how they download onto a webpage. Interalaced images download "lines" in an order that allows the image to download more quickly onto the page. The image appears fuzzy at first but then clears up as more lines are downloaded. Where as progressive images, download line by line from top to bottom. Interlaced images for the most part are larger than those which are prgoressive.

 

4. Define the following terms and how they relate to graphics:

 

Abbreviated  Name Full Name Owner File Extension Uses Advantages/Disadvantages
.ai Adobe Illustrator Adobe Systems .ai Adobe Illustrator files are editable using programs that support the format, such as Adobe Illustrator, Inkscape, CorelDRAW, etc.  .ai files are mainly meant for Adobe files and sometimes do not work outside of the program.
.bmp Windows bitmap Microsoft .bmp, .dib, .rle,
.2bp (2bpp)		 Used by many 2D applications. Large detailed files / Not good when zoomed in
.cdr CorelDRAW Corel Corperation .cdr, .ccx, .cdt, .cmx CorelDRAW files are editable using programs that support the format, such as CorelDRAW, Adobe Illustrator, Inkscape, etc.  Again these images work with spcific programs and outside of that they sometiems do not work.
.gif Graphics Interchange CompuServe,
Unisys (compression algorithm)		 .gif, .gfa, .giff Supported by most web browsers. Supports transparency and animation. GIF's are an excellent iamge format that can support movement as well as the fact that they can be used on most webpages.  
.jpeg Joint Photographic Experts Group Joint Photographic Experts Group .jpg, .jpeg, .jpe
(containers:
.jif, .jfif, .jfi)		 Photographic images. Supported by most web browsers. Quick loading and multi usable / sometimes not detailed
.pict Macintosh PICT Apple .pict, .pic, .pct,
.pct1, .pct2		 Metafile for Mac OS, not meant for print publishing.  These images are used for apples, and have issues transfering over to PC formats.
.png Portable Network Graphics World Wide Web Consortium .png W3C endorsed replacement for GIF. Supported by most web browsers. PNG's are slowly taking over what GIF's domianted, they are becoming more adapatable and useful.  
.psd Photoshop Document Adobe .psd, .psb, .pdb,
.pdd		 Used mainly for storing image manipulation & editing data.  PSD's are used for photoshop, and the RAW iamge usually is extremly large.
.swf Shockwave Flash Adobe .swf Supported by many web browsers via plug-in. Shockwave is a great application for sounds and video, however some of the older browsers and computers can't support it.  
.tiff Tagged Image File Format Adobe .tiff, .tif Document scanning and imaging format, also functions as a container.  TIFF's are the one file that was made to work between apples and PC's.
.wbmp Wireless Application Protocol Bitmap WAP Forum .wbmp, .wbm, .wbp Being able to adjust to the wirless market, which will be huge in the coming years.  WBMP's are able to be transfered to the internet while at the same time mainting their detail.

 

 

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