Lecture 7 Flashcards
In image memory each image is stored as
Frame of information
The storing of frames is
Continuous
Image memory freeze frame displays
Latest image stored in memory
Image memory cineloop displays
Last 100-130 images
Numbers are stored in the ________ accoring to the _____ of the echoes recieved from the corresponding anatomic locations
Memory elements (pixels)
Intensity
One matrix can only show ____ shades of grey (________ )
2
On and off
More than 2 shade of grey require
More matrices (more bits)
Working a one bit pixel you would only have
Two options 0 or 1
A 1 bit pixel is called
Bistable
4 bits per pixel means
4 bits deep
The amount of bits a pixel can have is
Binary
Each column in binar table represents
A bit
2 bit pixel has how many options
4
Bit depth/capacity is what
How many options
The majority of US machines use _______ bit memory
6-8
How many shades of grey can humans see in
100 shades
The binary number system is an alternative to
The decimal system
What is contrast resolution
Being able to serperate two different echoes as two different shades of gray
CR equation
CR=dB/shade
Compression affected
Dynamic range
What is dynamic range
Power ratio of largest to smallest amplitude
Why do we want compression to reduce the dynamic range
So we wont have as many different amplitudes to deal with
More bits/pixel =______ contrast resolution
Better
Is bits per pixel operator controlled
No, manufacturer dependent
How does more shades and more contrast appear
Granier
Other equation how contrast resolution
Contrast resolution = dynamic range/ bits-per-pixel
More pixels/ frame =
Better detail resolution
Not to be confused with contrast resolution
8 bits = ____ byte
1 bytes
1 kilobyte= _____ bytes
1024
When information is pulled from the image memory and post-processed it is ready to be sent to
Display
The display requires
Analogs signals
How is the information changed to analog
Digital to analog converter
In digital to analog converter digal memory (#s) —>
Voltages for display
