X-ray cannot show differences in tissue contrast that are less than.. - ANSWER
10% (contrast resolution)
____ and ____ are fixed and limited in the film? - ANSWER Optical range
and contrast
(you cannot window them)
The 4 steps in the digital process - ANSWER Data Acquisition
Image Processing
Image display, storage, and communication
Image Formations and Representation
Data Acquisition - ANSWER First step in the digital process
Attenuated data is collected by the detectors
The output signal is an analog electrical signalue
Must go through the ADC to become a digital signal for computer processing
Image Processing - ANSWER Performed by the digital computer
Takes the input digital image and processes it to produce an output image in the
digital binary form
Image Display, Storage, and Communication - ANSWER The output digital
image must be converted into an analog signal before it can be displayed on the
monitor using the DAC
Can be stored on a disk or sent electronically through networks
Image Formations and Representations of Analog Images - ANSWER Analog
images are continous images - X-ray images
Image Formation and Representations of Digital Images - ANSWER
Numerical representations or images of objects
Requires a digital computer
, Any info entered into a computer must be converted into digital form (numbers)
ADC - converts continuous signals to discrete signals
Digital Image Processing - ANSWER Converting an input image into an
output image
Both analog - analog processing
Both digital - digital processing
CT is based on reconstruction processes where a digital image is changed to a
visable physical image
Process - ANSWER A series of operations or actions leading to a desired
result
Spatial Location Domains - ANSWER Used in CT and radiography
The digital image is a numerical image arranged in a grid so the location of each
number can be identified using the x-y coordinate system
x - columns
y - rows
(0,0) upper left corner
Spatial Frequency Domains - ANSWER Used in MRI
Image domains - ANSWER Digital image processing can change one domain
into another domain
Use the Fourier Transform for this task
Characteristics of a digital image - ANSWER Matrix
Pixel
Voxel
Bit Depth
Matrix - ANSWER A 2 dimensional array of numbers that make up a digital
iamge
Consists of columns (M) and rows (N) that are broken up into pixels
Dimensions are M x N x k bits
Matrix size = FOV - selected by the tech
In CT we use 512 x 512
10% (contrast resolution)
____ and ____ are fixed and limited in the film? - ANSWER Optical range
and contrast
(you cannot window them)
The 4 steps in the digital process - ANSWER Data Acquisition
Image Processing
Image display, storage, and communication
Image Formations and Representation
Data Acquisition - ANSWER First step in the digital process
Attenuated data is collected by the detectors
The output signal is an analog electrical signalue
Must go through the ADC to become a digital signal for computer processing
Image Processing - ANSWER Performed by the digital computer
Takes the input digital image and processes it to produce an output image in the
digital binary form
Image Display, Storage, and Communication - ANSWER The output digital
image must be converted into an analog signal before it can be displayed on the
monitor using the DAC
Can be stored on a disk or sent electronically through networks
Image Formations and Representations of Analog Images - ANSWER Analog
images are continous images - X-ray images
Image Formation and Representations of Digital Images - ANSWER
Numerical representations or images of objects
Requires a digital computer
, Any info entered into a computer must be converted into digital form (numbers)
ADC - converts continuous signals to discrete signals
Digital Image Processing - ANSWER Converting an input image into an
output image
Both analog - analog processing
Both digital - digital processing
CT is based on reconstruction processes where a digital image is changed to a
visable physical image
Process - ANSWER A series of operations or actions leading to a desired
result
Spatial Location Domains - ANSWER Used in CT and radiography
The digital image is a numerical image arranged in a grid so the location of each
number can be identified using the x-y coordinate system
x - columns
y - rows
(0,0) upper left corner
Spatial Frequency Domains - ANSWER Used in MRI
Image domains - ANSWER Digital image processing can change one domain
into another domain
Use the Fourier Transform for this task
Characteristics of a digital image - ANSWER Matrix
Pixel
Voxel
Bit Depth
Matrix - ANSWER A 2 dimensional array of numbers that make up a digital
iamge
Consists of columns (M) and rows (N) that are broken up into pixels
Dimensions are M x N x k bits
Matrix size = FOV - selected by the tech
In CT we use 512 x 512
