A/D converter- a device used to an analog charge into digital form
Analog format- the principle feature of something in analog format is that
it is continuous
Bit depth- the number of bits of color or grayscale information that can be
recorded per pixel
Charge-coupled device [CCD]- a solid state, light sensitive chip receptor
that converts light into an analog charge
Digital format- data stored with measured values and distinct points or
positions
Drum scanner- a type of scanner that scans images mounted on a rotating
drum
Dynamic range- the gradations from light to dark that a digital imaging
device can read or produce
Film scanner- a specially designed CCD scanner that captures images from
various types of film
Handheld scanner- a small scanner is moved across a page or image by hand
Histogram-a graphic display of highlight, midtone, and shadow values that
correspond to the number of pixels affected in each part of the tonal scale
Interpolation- a mathematical technique used to increase the apparent
resolution of an image
Layers- a feature of image editing programs that creates multiple, editable
levellls of a single piece of artwork
Mask- a feature of image editing programs that protects a specified area of
an image from changes, filters, and other effects applied to the rest of
the images
Mottling- the blotchy or cloudy appearance of an image, instead of a
smooth, continuous tone
Newton’s rings- an undesirable color pattern that results from interference
between the exposure light and its reflected beam from the closest adjacent
surface
Optical character recognition- a system used to translate the bitmap image
of scanned text into ASCII characters
Paint effects- a feature of image manipulation programs that contains
several tools that allow the user to create and color images
Quantizing- a filtering process that determines the amount and selection of
data to eliminate, which makes it possible to encode data with fewer bits
Resolution- the sharpness and clarity of an image
Retouching tools- tools used in image manipulation programs to modify
images in ways similar to methods used in darkroom photography
Scan area- the section of a scanning device on which images are placed for
scanning
Scanner- measures the color densities of an original, stores the
measurements as digital information, manipulates or alters the data, and
uses the data to create four color separations
Screen ruling- the number of ruled grid lines per inch (lpi) on a halftone
screen
Spatial resolution- the ability of a digital imaging device to address data
in horizontal and vertical dimensions
Sweet spot- a 3″ or 4″ area in the center of a flatbed scanner at which the
scanner scans material at full resolution
Tonal resolution- the number of bits of color or grayscale information that
can be recorded per pixe
Unsharp masking- a f some scanners that increases tonal contrast where
light and dark tones come together at the edges of the images
Well sites- hundreds or thousands of photosensitive elements on a CCD
XY scanning technology- scanning technology that optimally positions the
scanning head along XY axis
REVIEW QUESTIONS
The colors and lines of an image in analog format are continuous. The
colors and lines of an image in digital format consist of values measured
at distinct points.
8. CCD sensors separate the red, green,and blue (RGB) light reflected by an
object
13. A histogram provides a display of the pixel information.
14. Typical storage devices used for images captured by common point and
shoot cameras would be:
– lens
– viewfinder and LCD
– batteries
– flash
– image stabilization
– exposure modes
– image capture time
– lighting conditions
15. Layers allow the user to create multiple levels of artwork that reside
on separate, overlapping layers in the same document.
16. Filters are used to apply special effects, such as patterns and
textures, to bitmap images.
17. A mask would be the image manipulation tool used to protect an area of
an image from changes and effects applied to the rest of the image.
