UVP Doc-It Life Science - Manual (Page 110)

Glossary
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Glossary
Artifact: In imaging, a flaw caused either by the imaging process or by the hardware itself. For example,
dust on the camera lens could cause small bright or dark spots in an image.
Aspect Ratio: The ratio between an image's width and its height. If the aspect ratio is not preserved, the
image will appear stretched or squashed.
Bits: The smallest units of computer measurement. A bit is a single binary value (i.e. it can be "on" or "off"
only). Bits typically are combined into units of eight, called "bytes." Modern computer processors work
with groups of 4 ("32-bit processor") or 8 ("64-bit processor") bytes at a time.
BMP: Microsoft Bitmap image file format. BMP is a lossless format which provides some compression to
reduce file size. BMP files generally have a BMP extension.
Control Handle: A small square at the corner (or similar point) of a graphical object that marks its extent
and indicates that the object is selected. Usually the object can be resized by dragging the control handle;
in some cases, different behavior results.
Electrophoresis: The movement of suspended particles through a fluid or gel through the application of
electrical current to the suspension medium.
Fidelity: The degree to which an image is true (i.e. accurate and uncorrupted) to the original scene it
represents. Also used in audio technology with the same meaning.
GIF: Graphic Interchange Format, a proprietary Xerox image compression format. GIF is a lossy
compression format that results in very small files. Files stored in GIF usually have a GIF extension.
Image Depth: The size (and thus range) of intensity numbers supported per pixel in an image. Doc-It
supports two depths: 8-bit (in which intensity numbers range from 0 to 255) and 16-bit (in which intensity
number range from 0 to 65535). For a more detailed explanation, see Inside a Pixel.
Intensity: The measure of brightness of a pixel. In a monochrome image, each pixel has a single intensity.
In a colored image, each pixel has three intensities: one for red; one for green; and one for blue. The
actual intensity values depend on an image's depth.
JPEG: A common lossy compression image format used to store images on disk. JPEG files generally
have JPG or JPEG extensions.
Lossless Compression: Compression schemes that preserve the image's integrity in full. Generally,
lossless compression results in much larger files than lossy compression on the same image.
Lossy Compression: Compression schemes that tolerate some pixel value changes to make the image
compress to a smaller size. Because the changes are irreversible, the image has "lost" some of its
original detail after such an operation.
Macro Mode: Close-up mode for a digital camera or web-camera. Macro mode is usually appropriate for
imaging microbiology slides.
Microbiology: The branch of biology dealing with microscopic forms of life.
Microscopy: The use of or investigation with a microscope.
Monochrome: Black-and-white, with shades of gray. Doc-It cameras capture 256 shades of gray in
monochrome mode.
Pixel: Short for "picture element." A pixel is a single dot in a computer image. The dot has a certain color
(for a color image) or an intensity (for a monochrome image). For a more detailed explanation, see Inside
a Pixel.
PNG: Portable Network Graphics, a common image format. PNG is a lossy compression format that
results in very small files. Files stored in PNG usually have a PNG extension.