Computer Knowledge

Digital Image Processing

2,103 Questions

Digital image processing involves manipulating digital images through various algorithms to enhance their visual quality or extract information. Key concepts include noise reduction, high dynamic range imaging, color correction, and sharpening techniques. These concepts are essential for computer science exams and technical certifications.

Color management systemsNoise reduction techniquesHDR image combiningImage sharpening techniquesAlpha matting process

Digital Image Processing Questions

Multiple choice

Which change detection technique utilizes a combination of multiple spectral bands to identify changes in the scene?

  1. Principal Component Analysis

  2. Image Differencing

  3. Image Ratioing

  4. Change Vector Analysis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Principal Component Analysis (PCA) is a change detection technique that transforms multiple spectral bands into a smaller number of principal components, which can be used to identify changes in the scene.

Multiple choice

What is the primary limitation of using image differencing for change detection?

  1. It is sensitive to noise

  2. It can only detect changes in magnitude

  3. It requires multi-temporal data

  4. It is computationally intensive
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Image differencing is sensitive to noise and other image artifacts, which can lead to false change detections.

Multiple choice

What is the fundamental principle behind the Vegetation Index Differencing (VID) change detection technique?

  1. Subtracting the pixel values of two vegetation indices

  2. Dividing the pixel values of two vegetation indices

  3. Multiplying the pixel values of two vegetation indices

  4. Taking the absolute difference between pixel values of two vegetation indices
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

VID involves subtracting the pixel values of two vegetation indices, such as NDVI, to highlight changes in vegetation cover.

Multiple choice

Which of the following is an example of a top-down processing approach in perception?

  1. Seeing a familiar object in an ambiguous image.

  2. Recognizing a word in a noisy sentence.

  3. Interpreting the meaning of a painting.

  4. Predicting the trajectory of a moving object.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Seeing a familiar object in an ambiguous image is an example of a top-down processing approach, where prior knowledge and expectations influence the interpretation of sensory information.

Multiple choice

Which type of digital zoom uses interpolation to create new pixels?

  1. Optical zoom

  2. Hybrid zoom

  3. Digital zoom

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Digital zoom uses interpolation to create new pixels, resulting in a loss of image quality.

Multiple choice

Which color space is commonly used for color correction in digital imaging?

  1. sRGB

  2. Adobe RGB

  3. ProPhoto RGB

  4. CMYK
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

sRGB (Standard Red Green Blue) is a widely adopted color space for digital imaging, including color correction. It is designed to represent colors accurately on standard consumer displays and is commonly used as the default color space for digital cameras and monitors.

Multiple choice

Which color correction technique is commonly used to remove unwanted color casts?

  1. White balance adjustment

  2. Color grading

  3. Histogram equalization

  4. Channel mixer adjustment
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

White balance adjustment is a color correction technique used to remove unwanted color casts from an image. It involves adjusting the color temperature of the image to achieve a neutral white point.

Multiple choice

What is the difference between color grading and color correction?

  1. Color grading is used for creative color adjustments, while color correction is for technical adjustments

  2. Color grading is used for video editing, while color correction is used for photo editing

  3. Color grading is used for adjusting the overall look of an image, while color correction is used for adjusting individual colors

  4. Color grading is used for color correction, while color correction is used for color grading
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Color correction involves making technical adjustments to ensure accurate color reproduction, while color grading is used for creative color adjustments to achieve a desired look or mood in an image.

Multiple choice

Which color correction technique is commonly used to adjust the overall contrast and brightness of an image?

  1. Levels adjustment

  2. Curves adjustment

  3. Color balance adjustment

  4. Hue/Saturation adjustment
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Levels adjustment is a color correction technique used to adjust the overall contrast and brightness of an image by manipulating the black point, white point, and gamma values.

Multiple choice

Which color correction technique is commonly used to adjust the hue, saturation, and lightness of individual colors?

  1. Hue/Saturation adjustment

  2. Vibrance adjustment

  3. Split toning

  4. Channel mixer adjustment
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Hue/Saturation adjustment is a color correction technique used to adjust the hue, saturation, and lightness of individual colors in an image. It allows photographers and designers to fine-tune the colors to achieve the desired look.

Multiple choice

Which color correction technique is commonly used to adjust the color temperature of an image?

  1. White balance adjustment

  2. Color grading

  3. Histogram equalization

  4. Channel mixer adjustment
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

White balance adjustment is a color correction technique used to adjust the color temperature of an image to achieve a neutral white point. This ensures that colors appear accurate and consistent under different lighting conditions.

Multiple choice

Which color correction technique is commonly used to adjust the overall color balance of an image?

  1. Color balance adjustment

  2. Curves adjustment

  3. Levels adjustment

  4. Hue/Saturation adjustment
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Color balance adjustment is a color correction technique used to adjust the overall color balance of an image by manipulating the cyan, magenta, and yellow values. This helps to correct color casts and achieve a more neutral color balance.

Multiple choice

What is the term used to describe the process of adjusting the color, contrast, and other visual properties of a film or video to achieve a desired look and feel?

  1. Color grading

  2. Color correction

  3. White balance

  4. Exposure
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Color grading is the process of adjusting the color, contrast, and other visual properties of a film or video to achieve a desired look and feel. It is used to enhance the overall visual quality and to create a specific mood or atmosphere.

Multiple choice

Which of these is NOT a common post-processing technique used to enhance architectural photographs?

  1. Adjusting exposure and contrast

  2. Cropping and straightening

  3. Applying filters and effects

  4. Adding motion blur
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Adding motion blur is generally not a common post-processing technique used to enhance architectural photographs, as it can detract from the static and structured nature of the subject matter.

Multiple choice

Which of the following is not a common post-processing technique used in dance photography?

  1. Color correction

  2. Cropping

  3. Sharpening

  4. HDR merging
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

HDR merging is not a commonly used post-processing technique in dance photography, as it is more suitable for landscape and architectural photography.