Sensors and Digital Imaging II

Question 1

what is qualitative digital imaging

Answer 1

• uses mathematical operations called matrix transformations
• magnify, adjust contrast, brightness, gray scale, colors, swap black and white

Question 2

what is analytical digital image processing

Answer 2

• measure lengths
• measure pixel values

Question 3

what are the digital image processing/modifications

Answer 3

• compression
• imaging manipulations
• automated image analysis
• image reconstruction

Question 4

describe compression

Answer 4

• affects image file size in memory storage
• useful for storage issues

Question 5

file memory size can be large due to:

Answer 5

• size of grid
• number of images
• bit depth

Question 6

what are imaging manipulations

Answer 6

• edge enhancement- sharpening
• noise reduction- softening
• optimization of density/contrast
• inversion of gray scale
• magnification
• emboss function
• pseudocolor enhancement

Question 7

what is analog to digital conversion

Answer 7

to be able to process and construct an image, the computer will turn the voltage signal to numbers and then to shades of gray

Question 8

how does the computer do image manipulation

Answer 8

it will change density values to predetermined numbers which then changes the image presentation

Question 9

what are imaging manipulations

Answer 9

post display mathematical algorithms that manipulate the digital signal

Question 10

do imaging manipulations increase diagnostic accuracy

Answer 10

NO

Question 11

what does the softening filter do/noise reduction

Answer 11

• remove high frequency noise
• may degrade or remove important diagnostic information

Question 12

what does the sharpening filter/ edge enhancement do

Answer 12

• remove low frequency noise, increases image contract
• exaggerates the contract difference between adjacent pixels, to increase contract all pixel values are stretched, the dark shades become darker and the light shades become lighter
• enhances local contract and makes edges sharper to diagnose caries, restortation fit and fracutres

Question 13

what does emboss do and when would it be usefull

Answer 13

• applies a 3D effect to the image
• could be useful in presentation situations

Question 13

what is included in automated image analysis

Answer 13

• length
• angles
• bone density
• area
• circumference