GCSE COMP 1 Unit 3 Sound

Calculating File Size and Sound

GCSE COMPUTER SCIENCE
COMPONENT 1 - Unit 3 Data Representation

Multiple Choice

The number of bits (audio bit depth) used to record each measurement is known as the _______?

• Resolution

• Depth

• Analysis

• Hertz

Drag and Drop

A Digital Sound File is created by

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analogue sound waves.

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sampling

amplifying

compressing

Drag and Drop

The highest rvalue in the recording is

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15

20

3

Drag and Drop

The Number of Bits used in the resolution is ​

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2

3

15

Drag and Drop

The Sample Rate is ​

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2

6

3

Drag and Drop

The File Size in Bits is​ ​

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18

9

27

Drag and Drop

The File Size in Bytes is​ ​ ​

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9.6

3

3.37

Fill in the Blanks

Digitising Sound

• Recording quality improves:

• the more accurately we record the wave height

• Increasing the sampling rate (frequency) means recording more data points

• Increasing the bit-rate improves the accuracy of each data point

Dropdown

The more ​

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we sample the sound, the recording quality ​

Select answer

Open Ended

State one device that is used to capture an analogue sound signal

Word Cloud

The length of a recording will heavily influence the size of the sound file.

State two factors other than recording length that determine the file size of a recording.

Lossy Compression

Removes sounds that we can’t easily hear or that least affect the perceived playback quality.

Leaves out some data from the original file, so the output can lose some sound quality.

Lossless Compression

Lossless compression formats are able to reduce the file size when compressed but do not lose any information.

File Formats

• WAV and AIFF files are uncompressed audio files

• Lossy file formats are still very popular as they reduce the file size well

• MP3 (MPEG-1 Audio Layer III)

• AAC (Advanced Audio Coding) – typically higher quality than MP3

Multiple Select

What is the formula for calculating the size of an uncompressed music file?

Select all the parts of the equation that are multiplied

• Sample Rate

• Bit Depth

• Resolution

• Duration

• Wave Length