Web Development Advanced And Miscellaneous : MCQs & PYQs with Explanation

Option A

Aspect ratio represents the proportional relationship between the width and height of an image, screen, or display. It tells how wide an image is compared to its height.
Aspect ratio is written in the form: Width : Height

• An aspect ratio of 16 : 9 means the width is 16 units and the height is 9 units.
• An aspect ratio of 4 : 3 is commonly used in older monitors and televisions.

Aspect ratio is important because it helps maintain the correct shape of images and videos without stretching or distortion.

Option B

Image Resolution represents the number of pixels present in one inch of an image. It is usually measured in Pixels Per Inch (PPI).
Given:

• Image Size = 2 inch × 2 inch
• Total Pixels = 512 × 512 pixels

Resolution = Number of Pixels / Image Size in Inches

• For Width : 512/2 = 256
• For Height : 512/2 = 256

Therefore, the image resolution is 256 pixels per inch.

Option D

In the MPEG video compression standard, a macroblock is a basic processing unit used for motion estimation, motion compensation, and other compression operations.
For MPEG-1 and MPEG-2 video, a macroblock generally consists of 16*16 pixels. So, one macroblock contains, 16*16 = 256 pixels.
A macroblock is further divided into smaller 8 * 8 blocks, which are used for operations such as the Discrete Cosine Transform (DCT).

Option A

A well-formed XML document follows basic syntax rules, but it does not require validation against a DTD (Document Type Definition). Validation is optional and is needed only for a valid XML document, not just a well-formed one.

Rules for a well-formed XML:

• Tags are case-sensitive.
• Elements must be properly nested.
• Every element must have a closing tag.

Option C

In computer graphics, an image displayed on the screen is stored inside a memory area called the Frame Buffer. The frame buffer stores information about each pixel of the image.
If only 1 bit per pixel is used, the image generally contains only black and white colors. This is called a Bit Map.
If multiple bits per pixel are used, more colors and image details can be stored. This type of frame buffer is called a Pix Map (Pixel Map).

• 1 bit per pixel : only 2 colors.
• 8 bits per pixel : 256 colors.
• 24 bits per pixel : millions of colors.

Option C

Lossy Compression is a compression technique in which some image data is permanently removed to reduce the file size. Because some information is discarded, the image may lose a small amount of quality.
JPG (JPEG) commonly uses lossy compression, making it suitable for photographs and web images where a smaller file size is important.

Option B

During digital image processing, an analog image is converted into a digital image using two important steps:

• Sampling.
• Quantization.

Sampling is the process of dividing the image into small discrete points called pixels.
Quantization is the process of assigning or digitizing the amplitude (intensity or brightness) values of pixels into discrete digital values.

Option C

MPEG (Moving Picture Experts Group) is a family of standards used for compressing and encoding digital audio and video.
MPEG specifications primarily define how multimedia data is represented and encoded as a bitstream, which is a sequence of bits (0s and 1s).

Option C

The .dib file extension stands for Device Independent Bitmap. It is a type of Bitmap Image format used in Windows.
A DIB stores bitmap image information in a way that is independent of the display device, meaning the image data is not tied to a particular graphics device.
The common bitmap file extension is .bmp, while .dib is another extension used for bitmap images.

Option B

In computer graphics, images displayed on the screen are stored temporarily in a special area of memory called the Frame Buffer. It stores the color and intensity information of every pixel of the image before the image appears on the display screen.