WorksheetsYear 11 compression
Total questions: 14
Worksheet time: 7mins
What is compression?
To convert one file to another
To reduce the size of data to save space
To minimise the time taken for a file to be downloaded
To compress something by pressing it very hard
What does Lossy compression do to files?
Increases the file size and keeps the same quality
Eliminates no information at all
Decreases the file size and keeps the same quality
Eliminates unnecessary information in a file to reduce file size
What is lossless compression?
No information is lost but file size is increased
There is no loss in information at all after compression
Files which have the exact same data after compression
Compression that involves an algorithm
What type of compression does the ZIP format use?
Lossy
Lossless
What type of compression would you use to compress a video?
Lossy
Lossless
What type of compression would you use to compress a text file?
Lossy
Lossless
What type of compression may remove some of the data?
Lossy
Lossless
Which of the following are not in a compressed format?
JPEG
MPEG
Bitmap
MP3
Uncompressed audio and video files require less memory than compressed files
True
False
Which type of compression does Huffman coding use?
Lossy
Lossless
How many bits does an ASCII character use?
7
1
2
6
In a Huffman Tree, which branch does the zero go?
Left
Right
How many bits are used to store the word PIT using ACSII?
3
21
28
1
How many bits will be used to store the word PIT when compressed with Huffman?
21
3
8
9
