Question 1

The process of compression both reduces the bandwidth required to transmit the data and the amount of storage space required to store it.

Accepted Answer

Compression algorithms are designed to remove redundant or unnecessary data from a file, resulting in a smaller file size. This smaller file size requires less bandwidth to transmit, and takes up less storage space on a device or server.

Question 2

Run-length encoding usually used in graphics is an example of lossy compression.

Accepted Answer

Run-length encoding (RLE) is a lossless compression technique used in graphics where repetitive patterns are replaced with a count value and a symbol. It does not lose any data during compression and can be reversed to obtain the exact original image. Therefore, RLE is an example of lossless compression.

Question 3

Video images generated by a camera are generally not suited for lossless compression techniques.

Accepted Answer

Video images are typically highly detailed and contain a lot of information, which makes them difficult to compress without losing some of that information. Therefore, lossy compression techniques are usually used for video compression.

Question 4

Lossy compression techniques generally compress the data that comprise those parts of the image the human eye is more sensitive to, or that contain more critical image data.

Accepted Answer

Lossy compression techniques generally remove or reduce the precision of less critical data or data to which the human eye is less sensitive, in order to reduce the overall size of the file.

Question 5

Fixed or constant bit rates (CBR) allow for consistent picture quality when the complexity of the image varies.

Accepted Answer

Fixed or constant bit rates (CBR) maintain a consistent bit rate, which can lead to varying picture quality as the complexity of the image changes. Variable bit rates (VBR) adjust to maintain consistent picture quality.

Question 6

Which of the following defines the standards for compressing moving images?&#10;A) JPEG&#10;B) Motion JPEG&#10;C) MPEG&#10;D) none of the above

Accepted Answer

MPEG (Moving Picture Experts Group) defines the standards for compressing moving images. JPEG is a standard for compressing still images, and Motion JPEG is a variation of JPEG which compresses each frame of a moving image as a separate still image.

Question 7

What form of compression uses spatial redundancy, or the repetition of data within the space of the frame, to define the data that can be discarded?&#10;A) intraframe compression&#10;B) interframe compression&#10;C) linear compression&#10;D) both C and D

Accepted Answer

Intraframe compression uses spatial redundancy to compress data within a single frame. It analyzes pixel data within the frame and identifies areas of similarity, allowing it to discard some of the redundant data to reduce file size. Interframe compression, on the other hand, analyzes the differences between frames and discards data accordingly. Linear compression is not a recognized compression method.

Question 8

The compression scheme that compares the unchanging portions of successive frames from one frame to the other is known as&#10;A) intraframe compression&#10;B) interframe compression&#10;C) linear compression&#10;D) both C and D

Accepted Answer

The compression scheme that compares the unchanging portions of successive frames from one frame to the other is known as interframe compression. Intraframe compression only considers the current frame being compressed and does not compare it to previous or future frames. Therefore, interframe compression is the best choice.

Question 9

Which of the following defines the standards for compressing still images such as for graphics and photographs?&#10;A) JPEG&#10;B) Motion JPEG&#10;C) MPEG&#10;D) none of the above

Accepted Answer

JPEG (Joint Photographic Experts Group) is a standard for compressing still images, particularly for photographs and graphics. Motion JPEG (MJPEG) is a standard for compressing video, while MPEG (Moving Picture Experts Group) is a standard for compressing both still and moving images. Therefore, the best choice would be A.

Question 10

What method represents an early attempt to compress moving images by treating each image as a single still picture? It is used in non-linear editing systems.&#10;A) JPEG&#10;B) Motion JPEG&#10;C) MPEG&#10;D) none of the above

Accepted Answer

Motion JPEG represents an early attempt to compress moving images by treating each image as a single still picture. It is often used in non-linear editing systems where individual frames need to be accessed and edited as separate entities. JPEG and MPEG are also video compression methods, but they differ from Motion JPEG in the way they compress moving images.

Deck 14: Compression