Digital Carter Chapter 7

Front 1

Archive Query

Back 1

software function that allows historical information to be gathered from digital storage, such as multiple examinations, a range of dates, or by pathology

Front 2

Automatic Rescaling

Back 2

occurs when exposure is greater or less than the optimal amount to produce a diagnositic image; it is the effort of the computer to "fix" exposure errors

Front 3

Contrast Manipulation

Back 3

conversion of the digital image using contrast enhancement parameters

Front 4

Edge enhancement

Back 4

enhancement occurs when fewer pixels in the neighborhood are included in the signal average; the smaller the neighborhood, the greater the enhancement

Front 5

High-Pass filtering

Back 5

technique for the enhancement of contrast and edge that amplifies the frequencies of areas of interest that are known (those frequencies that can be ammmmplified) and suppresses frequencies outside the area of interest)

Front 6

Histogram

Back 6

graphic representation of all the digitally recorded signals of a digital x-ray exposure

Front 7

Image Annotation

Back 7

software function that allows text or markers to be digitally added to an image

Front 8

Low-pass filtering

Back 8

result of averaging each pixel's frequency with surrounding pixel values to remove high frequency noise, the result is a reduction of noise and contrast; useful for viewing small structures such as fine bone

Front 9

Magnification

Back 9

enlargement of an image in all dimensions without loss of sharpness

Front 10

Manual send

Back 10

computer function that allows images to be sent to specified reading stations

Front 11

Modulation Transfer Reduction

Back 11

Ability of a system to record available spatial frequencies

Front 12

Nyquist Theorem

Back 12

When sampling a signal such as the conversion from an analog to a digital image, the sampling frequency must be greater than twice the bandwidth of the input signal so that the reconstruction of the original image will be nearly perfect.

Front 13

Patient Demographics

Back 13

input information regarding patient age, identifying number, ordering physician and so on.

Front 14

Shuttering

Back 14

used to blacken out the white collimation borders ina digital image, effectively eliminating veil glare.

Front 15

Smoothing

Back 15

also know as low-pass filtering, the result of averaging each pixels frequency with surrounding pixel values to remove high frequency noise.

Front 16

Spatial Frequency Resolution

Back 16

amount of detail or sharpness in a digital image

Front 17

Window

Back 17

image manipulation parameter that changes screen image brightness, usually through the use of a mouse

Front 18

Image Orientation

Back 18

identification of the top or side of an image

Front 19

Image Sampling

Back 19

amount of information gathered from pixel storage

Front 20

Image stitching

Back 20

process of 'sewing" together multiple images to form a continuous image.

Front 21

Latitude

Back 21

amount of error that can be made in exposure factor choice and still result in the capture of a quality image.

Front 22

Level

Back 22

image maniipulation parameter that changes screen image contrast usually through the use of a mouse.

Front 23

Look-Up Table (LUT)

Back 23

reference histogram of the luminance values derived during image acquisition.