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Unformatted text preview: h encoding of image: lossless .gif works by reducing 24 bit color by rounding to 256 colors (8 bits total per pixel) derived from the image, then using LZ compression. Good for drawings, images without great color depth. .jpg (too complex to describe here) advantages over gif: many colors (note: uses Huffman coding) Pros and cons: gif good for sharp lines, bad for good color. jpg good for photographs.
.gif and .jpg are lossy compression techniques. Vectorbased representations
(as opposed to “bitmap” = .bmp, .gif, .jpg) Store equations of lines, edges, regions Very efficient for geometric contents Scales beautifully Scalable fonts without jaggies Flash files Disadv: hard to obtain directly from scanned images, hard to edit pixelwise http://www.cambridgeincolour.com/tutorials.htm Video
Video Video = many, many, many, many images
Typical 30 frames per second.
Space requirement is simply: (space per image) x (#seconds) x 30
Example: 600 x 600 truecolor image = 1.08 Mb
Thus, roughly 30Mb per second. 540...
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- Fall '09
- Computer Science