Registry Review

1
Registry Review

• Digital Imaging Considerations (Image Production
  and Evaluation)

2
Why Digitize?DUH to make images better!

• Image enhancement improve contours and
  shapes-contrast enhancement, edge enhancement,
  spatial and frequency filtering, image combining
  and noise reduction

3
Image restoration

• Improve the quality of the images uses filters
  and other enhancements to make viewing the image
  better

4
Image analysis

• Measurements and statistics performed on the
  images image processing image segmentation,
  feature extraction and classification of objects
  Isolate and highlight the objects of interest
  and classify into specific categories (3-D image
  formation)

5
Image Compression

• Just like WINZIP compresses files/images so
  they can be transmitted and also decrease the
  storage amount

6
Image Synthesis

• Creates images from other images or non-image
  data esp. for CT and MRI and 3-D imaging

7
Image Processing

• Point Operations input image pixel is mapped.
  Algorithms enable the input matrix to be scanned
  pixel by pixel until the whole image is
  transformed sometimes called gray-level
  mapping via using a look up table (LUT)
  plots the input and output GRAY levels. Modifies
  the histogram of pixel values.

8
Histogram

• Indicate the overall BRIGHTNESS and CONTRAST of
  the image via
• Histogram modification
• Histogram stretching

9
Spatial Frequency Filtering

• Also called high Pass Filtering sharpens the
  image in the spatial domain that seems blurred
  uses algorithm that converts the image to spatial
  frequencies that can be filtered and concentrates
  on the BEST spatial frequencies which makes a
  better image!

10
Spatial Frequency Filtering

• Low pass filtering smoothing process to
  reduce noise

11
Computed Radiography (CR)

• PSL- photostimulable luminescence
• PSP- photostimulable phosphor
• SPS storage phosphor screen
• IP- imaging plate
• SP- storage phosphor
• PMT photomultiplier tube
• PD - photodiode

12
PSPs

• (photostimulable phosphor) is where the latent
  image is stored sometimes called storage
  phosphor screens (SPSs). Thse are encased in the
  cassette sometimes called the IMAGING PLATE

13
Laser reading of the image

• A stimulating laser reads/converts the latent
  image to electrons AND erases the latent image
  from the IP/PSPs
• Powder vs needle PSPs

14
Review Chapters 24, 25, 26

• ON the UNLV Radiography Program website (under
  Pales then 254) for the computed/digital
  PowerPoint slides!