A computer has a microphone and captures a voice recording using sound editing software. The user can select the sampling resolution before making a recording. Define the term sampling resolution. Explain how the sampling resolution will affect the accuracy of the digitised sound. Sampling resolution Explanation The computer also has bitmap software. Define the term image resolution. A picture is drawn and is saved as a 16-colour bitmap image. State how many bits are used to encode the data for one pixel. A second picture has width 8192 pixels and height 256 pixels. It is saved as a 256-colour bitmap. Calculate the file size in kilobytes. Show your working. The actual bitmap file size will be larger than your calculated value as a bitmap file has a file header. State two items of data that are stored in the file header.

9608_s17_qp_12

THEORY

2017

Paper 1, Variant 2

View

A computer has a microphone and captures a voice recording using sound recording software. Before making a recording, the user can select the sampling rate. Define the term sampling rate. Explain how the sampling rate will influence the accuracy of the digitised sound. Sampling rate Explanation The computer also has bitmap software. Define the terms pixel and screen resolution. Pixel Screen resolution A picture has been drawn and is saved as a monochrome bitmap image. State how many pixels are stored in one byte. A second picture has width 2048 pixels and height 512 pixels. It is saved as a 256-colour image. Calculate the file size in kilobytes. Show your working. The actual bitmap file size will be larger than your calculated value. State another data item that the bitmap file stores in addition to the pixel data.

9608_s17_qp_13

THEORY

2017

Paper 1, Variant 3

View

A logo is designed as a bitmap image. Describe what is meant by a bitmap image. A black and white bitmap image is shown. Explain how a computer can store this bitmap image. The image is compressed before it is attached to an email. Explain how run-length encoding (RLE) will compress the image. The finished logo is 500 pixels by 1000 pixels and uses 35 different colours. Estimate the file size for the logo. Give your answer in kilobytes. Show your working. Working Answer The logo is redesigned as a vector graphic. State two benefits of a vector graphic compared to a bitmap image. Give a reason for each benefit. Benefit 1 Reason 1 Benefit 2 Reason 2

9608_s18_qp_11

THEORY

2018

Paper 1, Variant 1

View

A black and white bitmap image is shown. State the minimum number of bits needed to represent each pixel in this image. Run-length encoding (RLE) is used to store the image with the following colour codes. Colour Code Black 1A White 3B Show how run-length encoding is used to store the image. An image has 30 different colours. State the minimum number of bits needed to represent each pixel in the 30-colour image. When the image is saved, a header is added to the file. State the purpose of the file header. Give two examples of the file header contents. Purpose Example 1 Example 2 Graphics software is used to edit a digital photograph. Give three features of graphics software that can be used to edit the photograph. Describe the effect each has on the photograph. Feature 1 Effect Feature 2 Effect Feature 3 Effect

9608_s18_qp_13

THEORY

2018

Paper 1, Variant 3

View

Xander creates a presentation that includes images, video and sound. The images are bitmap images. A bitmap image can be made up of any number of colours. Each colour is represented by a unique binary number. Draw one line from each box on the left, to the correct box on the right to identify the minimum number of bits needed to store each maximum number of colours. Maximum number of colours Minimum number of bits One of the videos has a frame rate of 40 fps (frames per second). State what is meant by 40 fps. One video uses interlaced encoding, and a second video uses progressive encoding. Describe two differences between interlaced and progressive encoding. The sound track has a sampling rate of 88.2 kHz and a sampling resolution of 32 bits. State what is meant by a sampling rate of 88.2 kHz and a sampling resolution of 32 bits. Sampling rate of 88.2 kHz Sampling resolution of 32 bits

9608_s19_qp_13

THEORY

2019

Paper 1, Variant 3

View

Samira is creating an interactive, multimedia presentation for the entrance to her hotel. The presentation will be on a device that has a resistive touchscreen for user input. Complete the following paragraph about the basic operation of a resistive touchscreen. The resistive touchscreen has two layers with between the layers. When a finger touches the screen, the moves to touch the ; this creates a point of contact. The and position of this point is calculated. Samira uses a computer to draw a logo for her hotel and saves it as a vector graphic. The logo will be placed on the multimedia presentation and elsewhere, such as on signs at the entrance of the hotel. Samira emails the logo to a company that prints signs, and other documentation for the hotel. Describe how the logo is represented by the computer. State two reasons why the hotel logo is saved as a vector graphic instead of a bitmapped graphic.

9608_s20_qp_12

THEORY

2020

Paper 1, Variant 2

View

Xiaoming created the following logo using bitmapped graphics software. PJF Interiors Describe how one typical feature of bitmapped graphics software was used to create the logo. The finished logo is 160 pixels wide and 160 pixels high. The image has a colour depth of 3 bytes per pixel. Calculate an estimate of the file size for the logo. Give your answer in kilobytes. Show your working. Working Answer KB Xiaoming needs to use his logo on his business card, on his website and on large display boards. He is told that he should have created a vector graphic logo instead of a bitmapped graphic logo. Describe one benefit of creating a vector graphic logo instead of a bitmapped graphic logo. The hexadecimal colour value of the background of Xiaoming’s website is: 913C8E Complete the following table by converting each hexadecimal value to denary value. Red Green Blue Hexadecimal value 3C 8E Denary value Part of Xiaoming’s website contains the JavaScript function performTask(). function performTask(){ var value1; value1 = document.getElementById("FirstBox").value; if (value1 == "Yes"){ document.getElementById("paragraph1").innerHTML = "Agreed"; } else if(value1 == "No"){ document.getElementById("paragraph1").innerHTML = "Sorry"; } else { alert("Error") } } Describe the purpose of the following JavaScript statements from the function performTask(). alert("Error") value1 = document.getElementById("FirstBox").value; document.getElementById("paragraph1").innerHTML = "Agreed";

9608_s20_qp_13

THEORY

2020

Paper 1, Variant 3

View

Zak designs a logo for his company. He uses vector graphics software to create the logo. One of the drawing objects in the logo is a circle. Identify four properties of the circle. Describe what is meant by a drawing list using the logo as an example. Zak could have used a bitmapped image for the logo. Describe two drawbacks of using a bitmapped image for the logo instead of a vector graphic. Drawback 1 Drawback 2 Zak’s company holds details about clients in a database. Give three security measures that Zak can implement to make sure that only authorised employees can access the data.

9608_s21_qp_11

THEORY

2021

Paper 1, Variant 1

View

Sam is a photographer. She has an image library of over 10 000 images. She stores the images on a high capacity magnetic hard disk. Explain why Sam would use the following utility software. Backup Defragmenter Disk repair The images are stored as bitmap files. Identify four items that will be stored in the header of a bitmap file. The bitmap images are compressed for use on a website. Tick (3) one box to select the most appropriate type of compression for the images used on the website and justify your answer. Lossy Lossless Justification

9608_s21_qp_12

THEORY

2021

Paper 1, Variant 2

View

Six computer graphics terms and seven descriptions are shown below. Draw a line to link each term to its correct description. Term Description Bitmap graphic Image file header Image resolution Pixel Screen resolution Vector graphic Measured in dots per inch ; this value determines the amount of detail an image has Picture element Image made up of rows and columns of picture elements Image made up of drawing objects. The properties of each object determine its shape and appearance. Specifies the image size, number of colours, and other data needed to display the image data Number of samples taken per second to represent some event in a digital format Value quoted for a monitor specification, such as 1024 × 768. The larger the numbers, the more picture elements will be displayed. A black and white image is 512 pixels by 256 pixels. Calculate the file size of this image in kilobytes (KB) (1 KB = 1024 bytes). Show your working. Give a reason why it is important to estimate the file size of an image.

9608_w15_qp_11

THEORY

2015

Paper 1, Variant 1

View

---