Tell students:
We use shortcuts all the time in daily life: a common example is in texting.
Popular abbreviations can speed up communication, and with no loss of meaning for those who are familiar with them
Compression techniques are needed to reduce the size of data transmissions. This lesson examines techniques that achieve this.
One category results in a loss of data but still retains sufficient data to convey the message (such as an image, audio or video) whereas the other can restore all original data following transmission. These two approaches are known as lossy and lossless compression respectively.
Introduce ‘lossless’ compression as used by Portable Network Graphics (PNG). This is achieved using a combination of Huffman and LZW (the initials of the three inventors) compression algorithms and involves two steps:
Have students submit a one-page report, including image screenshots, to explain and evaluate lossy and lossless image compression techniques.