A bitmap image is a spatially mapped array of bits. It is simply a file holding an array of 1s and 0s which when arranged create a shape, (eg a square) forms an images.
Vectors
vector graphics are much, much smaller in file size and do not suffer from this scaling problem. This is how they achieve it;
instead of storing the image as a set of pixels they store the instructions (genetic info and properties) needed to recreate the image
eg. rect(0,0,2700,2700,black,filled,none)
The advantages
- Smooth scaling
- Smaller files
- load faster from storage
Compression
There are two methods of compression;
first options with out losing any information - run length encoding (RLE) replaces continuous blocks with just the colours and numbers of the blocks
second option throwing away some information - remove bits we find hard to see/wont notice (JPEG)
- every time you save a JPEG again as a JPEG you lose more info
Well done - the main point of improvement would be to include an example of calculating the file size of an image and also to talk about colour depth and how that impacts file size
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