SA combined

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SA2
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We can think of a pixel value as a function that maps itself to values 0 to 255 in a grayscale image.
  True

Which imadjust command should be applied to invert image img.
  imadjust(img, [], [1,0]) 

It processes the image as a single block.
  Spatial Filters 

The imadjust is a function in Matlab that allows us to add a constant value on an image.
  True 

A function in Matlab that allows us to perform histogram stretching. (answer the function name only)
imadjust

To do double thresholding, we need to select a value for T that will serve as threshold value wherein all pixel values greater than T will turned into black and white for the rest(or vice versa)
  False 

We can remove unnecessary details from an image using thresholding.
  True 

Threshold is some fixed value which draws a boundary line between two set of data.
  True 

We can use the relational operator to do thresholding in Matlab.
  True 

Image thresholding is a simple segmentation method yet powerful.
  True

The Gaussian filter may result in linear averaging. Write a command using fspecial function that will use gaussian but behave as 3 by 3 averaging filter. (do not include unnecessary spaces, end your command with a semicolon)
  fspecial('gaussian',[3,3]);

The result of filter2 function in Matlab is a matrix of data type uint8.
  True 

These are pixels surrounding a given pixel.
  neighborhood 

It is convenient to describe a linear filter simply in terms of the coefficients of all the grey values of pixels within the mask.
  true

In padding values on the edges of an image, we can randomly select values for all necessary values outside the image.
  false

it does this by padding with zero, and applying the filter at all places on and around the image where the mask intersects the image matrix.
  full


A pixel in an N4(p) is considered in N8(p).
  true

A pixel in an N8(p) is considered in Nd(p).
  never?

It passes over the low-frequency components and reduces or eliminates high-frequency components.
  low pass filter

Gaussian filters are a class of high-pass filters, all based on the Gaussian probability.
  false

This noise effect is of bars over the image.
 periodic

Rank-order filtering allows us to choose the median of a non-rectangular mask.
  true

Using ‘speckle’ in imnoise function give us a default variance of 0 if not changed.
  false

This noise is a major problem in some radar applications.
  speckle

Median filtering is a special case of a more general process called rank-order filtering.
  true

Write a Matlab command that will implement a default gaussian blur on an image img. (do not include unnecessary spaces on your answer, end your command with a semicolon)
imnoise(img,'gaussian'); ??

It is an idealized form of white noise.
  gaussian

There is no built in Matlab function for this.
  outlier method

A noise caused by random fluctuations in the signal.
  gaussian

This method of noise cleaning seems like tailor-made for salt & pepper.
  Median filtering
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SA3
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We may use edges to measure the size of objects in an image and isolate the from their background.
  True 


The given below equation for getting the difference is called __________.

  forward difference

Robert cross-gradient filter is an example of second differences filters.
  false


Write a Matlab command that will apply zero-crossing on image ‘img’ with Laplace ‘lap’. (do not include unnecessary spaces on your answer, end your command with semicolon)
  edge(img,'zerocross',lap); ??

Write a Matlab command that uses fspecial implements unsharp filter with an alpha value of 0.5 (do not include unnecessary spaces on your answer, end your command with a semicolon).
fspecial('unsharp',0.5);

Sober filters are used for edges enhancement of an image.
  false

The given filter finds what kind of edges.

  vertical

Edge enhancement may also be called unsharp masking.
  true

The given filter finds what kind of edges.

  horizontal

The Sobel filters are like the Prewitt filters, in that they apply a ________________.
  smoothing filters

It is the total amount of energy that flows from the light source, which is measured in watts.
  Radiance

It is a Matlab function that converts HSV image to RGB color model. (answer using the function name only)
  hsv2rgb

A light that has no color is called __________.
  Achromatic

Given the colors below, how many of them belong to the secondary color of pigments.
Red, Green, Black, White
!3 ??

The human visual system can distinguish hundreds of thousands of different color shades and intensities, but only around 100 shades of grey.
  true

It is a Matlab function that converts the YIQ image to the RGB color model. (answer using the function name only)
  ntsc2rgb

A full spectrum colors are purely saturated.
  true

Hard to measure, embodies the achromatic notion of intensity, used to describe the color sensation.
  brightness

In the CMY model cyan is the negative of red in RGB which can be calculated as 1 – R.
  true

Cyan is a primary color of pigments.
  true

RLE is widely use in file with format such as PNG, JPG and more.
  false

Image compression is the process of converting an image file in such a way that it consumes the same space as the original file.
  false

Given the string ‘AAABBBCCC’, what is the new string value after applying the RLE? (write your answer in one string do not include spaces)
3A3B3C

Huffman relies on analysis of frequency on an image.
  true

There is a permanent loss of information in lossless compression.
  false

RLE is an example of lossy image compression technique.
  false

Lossy compression is the family of data encoding method that utilizes imprecise estimates to represent the content.
  true

There is a permanent loss of information in lossy compression.
  true

An 8-bit color image has a size of 25 bytes.
  false

The psycho-visual redundancy considers the processing within our brain, this is the data which is neglected by human visual-system.
  true