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 of the following is NOT a common HDR photography post-processing technique for reducing noise?

  1. Median filter

  2. Gaussian blur

  3. Denoise algorithm

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

HDR merging is a technique for combining multiple exposures into a single HDR image, not for reducing noise.

Multiple choice

Which of the following is NOT a common HDR photography post-processing technique for improving image sharpness?

  1. Unsharp mask

  2. High-pass filter

  3. Median filter

  4. Gaussian blur
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Median filter is a noise reduction technique, not a sharpening technique.

Multiple choice

Which of the following is NOT a common HDR photography post-processing technique for creating a more artistic and stylized image?

  1. HDR toning

  2. Color grading

  3. Vignette

  4. Noise reduction
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Noise reduction is not a technique for creating a more artistic and stylized image, but rather for improving image quality.

Multiple choice

Which of the following is NOT a common HDR photography post-processing technique for merging multiple exposures?

  1. Exposure blending

  2. HDR merging

  3. Focus stacking

  4. Tone mapping
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Focus stacking is a technique for combining multiple images with different focus points to create a single image with extended depth of field. It is not commonly used for merging multiple exposures in HDR photography.

Multiple choice

Which of the following is NOT a common HDR photography post-processing technique for reducing halos and artifacts?

  1. Tone mapping

  2. Exposure blending

  3. Local contrast adjustment

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

HDR merging is a technique for combining multiple exposures into a single HDR image, not for reducing halos and artifacts.

Multiple choice

Which of the following is NOT a type of texture?

  1. Diffuse texture

  2. Normal map

  3. Specular map

  4. Displacement map
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Displacement maps are not a type of texture. They are a type of geometry map that can be used to add detail to a surface.

Multiple choice

How can white balance be adjusted in post-processing?

  1. Using a color correction filter

  2. Adjusting the color temperature

  3. Using a white balance dropper tool

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

White balance can be adjusted in post-processing using a variety of methods. One common method is to use a color correction filter. This filter can be applied to the entire image or to specific areas of the image. Another method is to adjust the color temperature. This can be done using a slider or by entering a specific value in degrees Kelvin. Finally, a white balance dropper tool can be used to select a neutral gray area in the image and set the white balance accordingly.

Multiple choice

Which sharpening method is commonly used for street photography?

  1. Unsharp Mask

  2. High Pass Filter

  3. Median Filter

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

Unsharp Mask is a popular sharpening method used in street photography due to its ability to enhance the sharpness of the image while preserving the overall detail.

Multiple choice

What is the primary adjustment made in the Unsharp Mask sharpening method?

  1. Amount

  2. Radius

  3. Threshold

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In the Unsharp Mask sharpening method, adjustments are made to the Amount, Radius, and Threshold to control the intensity, spread, and sensitivity of the sharpening effect.

Multiple choice

What is the function of the Radius parameter in the Unsharp Mask sharpening method?

  1. It determines the size of the sharpening radius

  2. It controls the strength of the sharpening effect

  3. It sets the threshold for detecting edges

  4. It adjusts the contrast of the image
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Radius parameter in the Unsharp Mask method determines the size of the sharpening radius, affecting the spread of the sharpening effect around the edges.

Multiple choice

How can you minimize the risk of over-sharpening a street photography image?

  1. Use a sharpening method that allows for precise control

  2. Apply sharpening selectively to specific areas of the image

  3. Start with a low sharpening amount and gradually increase it until the desired result is achieved

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

To minimize the risk of over-sharpening, use a sharpening method that allows for precise control, apply sharpening selectively to specific areas of the image, and start with a low sharpening amount and gradually increase it until the desired result is achieved.

Multiple choice

Which of the following is not a common sharpening technique used in street photography?

  1. Unsharp Mask

  2. High Pass Filter

  3. Median Filter

  4. Smart Sharpen
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Median Filter is a noise reduction technique and not a sharpening technique commonly used in street photography.

Multiple choice

What is the primary difference between Unsharp Mask and High Pass Filter sharpening methods?

  1. Unsharp Mask sharpens edges, while High Pass Filter sharpens details

  2. Unsharp Mask sharpens the entire image, while High Pass Filter sharpens only the high-frequency areas

  3. Unsharp Mask is more suitable for street photography, while High Pass Filter is more suitable for landscape photography

  4. Unsharp Mask is more computationally intensive than High Pass Filter
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Unsharp Mask primarily sharpens edges, while High Pass Filter sharpens details by enhancing the high-frequency areas of the image.

Multiple choice

Which of the following is a common change detection technique that involves comparing two or more images of the same area taken at different times?

  1. Image Differencing

  2. Image Ratioing

  3. Principal Component Analysis

  4. Vegetation Index Differencing
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Image differencing involves subtracting the pixel values of two images taken at different times to highlight changes in the scene.

Multiple choice

What is the fundamental principle behind image ratioing for change detection?

  1. Dividing the pixel values of two images

  2. Subtracting the pixel values of two images

  3. Multiplying the pixel values of two images

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

Image ratioing involves dividing the pixel values of two images to highlight changes in the scene.