Chapter 15 Flashcards
Which electronic component is required for gray scale imaging?
Scan converter
Which of the following scan converters will provide the best spatial resolution?
1000 x 1000 pixels
Which of these statements regarding a bit of computer memory is false?
It is the smallest element of an image
How many gray shades can be represented by a group of
4 bits
2 bits
16 shades
4 shades
Tip: multiply by itself
What is the number of shades that can be represented by 3 bits?
8
Tip: 2x2x2=8
What is the number of shades that can be represented by 8 bits?
256
Tip: 2x2x2x2x2x2x2x2=256
What is the number that can be represented by 10 bits?
1024
Tip: 10x10x10x10x10x10x10x10x10x10=1024
What is the number of shades that can be represented by n bits?
2
How many bits are needed to store:
10 shades of gray
11 shades of gray
15 shades of gray
4 bits
Which of the following statements regarding a pixel is false?
It displays up to 3 gray shades simutaneously
Are the following procedures usually pre- or postprocessing?
- Modifying a frozen image
- Read zoom
- Write zoom
- Adjusting the brightness on the monitor
- Increasing the receiver gain
- Postprocessing
- Postprocessing
- Preprocessing
- Postprocessing
- Preprocessing
What is the primary disadvantage of video tape and computer disc methods of image archiving?
The information id vulnerable to erasure when exposed to strong magnetic fields
Where does coded excitation take place?
In the pulser
Which of the following is not true about spatial compounding?
Can be performed with a mechanical transducer
All of the following are advantages of PACS systems except:
Images have higher resolution than what appears on the system’s display
