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Image Compression and File formats

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When you are dealing with image size you have to look at image compression. There are many choices you can make regarding image sizes, compression, and file formats. The initial size of the image after you have taken it is huge. This is because each pixel requires 24 bits to store information. Look at it this way. If you take a picture in low resolution you have an image that is about 3 megabytes. At mid-resolution it is about 9 megabytes, and at high resolution it is up to 18 megabytes. Because of this the files are two large to store. In order to work around this problem, digital cameras use compression to lower the resolution, without losing picture quality, so you can store, display, edit, and transfer your images quickly and efficiently.

The above paragraph mentions compression. Well just how is compression defined? When an image is compressed, any data that appears duplicated or has no value to the image being shown is eliminated. This way only those bits that are valid are saved. An example of this, if the image has an abundance of blue color, only one pixel of that color is saved.

Digital cameras use two forms of compression: lossless and lossy:

• Lossless compression: This form of compression uncompresses an image so its quality matches the original image. This way there is nothing lost in the image being reduced. Most of these images are in TIFF or RAW file formats.
• Lossy compression: Lossless compression is not the best way to compress pictures so cameras provide a better compression known as lossy compression. Most of these images are in JPEG format.

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