image modifications Flashcards
Compression
affected by?
– affects image file size in memory storage
- useful for storage issues eg. “zipping” files
- actual file size is larger that stored file size
- compression is an algorithm tha can shrink thefile size for storage and recreate the data when retrieving the data
•File memory size can become quiet largedue to
– size of grid (sensor size)
- number of images
- bit depth
types of image manipulation
➢ Edge Enhancement – sharpening filter
➢ Noise Reduction – softening filter
➢ Optimization of density/contrast
➢ Inversion of gray scale
➢ Magnification
➢ Emboss function
➢ Pseudocolor enhancement
what manipulation is this
grey scale inversion
what adjustment was made here
adjustment contrast/brightness
what is the issue with this x ray, how can it be fixed?
overrexposure, density optimization
how was this image changed
decreased contrast
how was this image changed
edge enhancement/ sharpening
how was this altered
noise reduction/ softened
noise reduction?
Remove high-frequency noise
May degrade or remove important diagnostic information
edge sharpening
Remove low-frequency noise; increases image contrast
Exaggerate the contrast difference between adjacent pixels; to increase contrast, all pixel values are stretched; the dark shades become darker and the light shades become lighter
Enhances local contrast and makes edges sharper to diagnose caries, restoration fit, and fractures
simulates disease; crown/ restoration failure
emboss function
Applies a three dimensional effect to the image
Could be useful in presentation situations
automated image analysis tools
•Length (in MiPACS viewer)
•Angles
•Bone Density
•Area
•Circumference
• Image reconstruction
Data is utilized by other software programs and produces different image presentations
creates a 3D image from planes of data
what do these mean
Brightness/Contrast Adjustment
The brightness and contrast adjustments are done together to subjectively find the “best” combination of brightness and contrast to highlight the clarity of the structures in the image
can image manipulation increase diagnostic ability
no
