Image Files

Needs an introductory paragraph. Also move the wavelet compression to the end of the page. Raster amd vector information is more important. (Grant Mac)

Wavelet Compression

Wavelet compression is a special type of compression that has only recently been adopted into digital media compression.
Instead of treating the image as numbers, the computer saves the file as a signal or wave. The computer then simplifies the wave by finding the average of the adjacent points and saving that which reduces the resolution by half. These averages are averaged and averaged again making simple waves. This is called decomposition.
The simplified version is saved along with the information necessary to reconstruct the original. With such small data, the information can be encoded as a compressed image. The final image can be based on a simplified version, with only the most significant detail added back into the wave.

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Raster Images

Raster images are essential as they are one of the most common files types used in digital printing and camera images. This images type has a few common file formats such as, TIFFs, JPEG/JFIFs, and GIFs.
Raster images are measured using pixels because raster images cannot be enlarged without losing quality, different suppliers have specific size requirements for their processes; they require a specific pixel resolution. The amount of pixels within each inch in the image represents the image pixel resolution or ppi (pixels per inch)
Raster images are internally very simple in terms of its code make up. If you look at the coding you will generally find some brief information describing the structure of the file and these having a series of numbers, each describing the colour of individual pixels.
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How to calculate what size you can print your image to obtain best quality.
Examples:
If your image is 1993 pixels wide & printer requires 300 dpi (1993 ÷ 300) can be printed at 6.643 inches
If your image is 1993 pixels wide & printer requires 240 dpi (1993 ÷ 240) can be printed at 8.304 inches

Vector Images

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