Computing - Images
In one sentence, how does a camera work?
Approximating a real image by cutting it up into a grid using a light sensor.
How is the grid of colour converted into binary in a camera?
Using an analogue-to-digital converter.
What is a bitmap?
A grid of pixels.
What’s another word for raster graphics?
Bitmap graphics.
What is a common bitmap file type?
- BMP
- JPG
- GIF
- PNG
- TIF
What is special about a BMP file?
It is uncompressed.
What is the definition of resolution?
What’s another name for $1,000,000$ pixels?
1 megapixel.
Why doesn’t resolution affect the physical size of an image?
Because the size of each pixel in the image can grow or shrink to fit the size of the screen.
What is bit depth in image representation?
The amount of bits allocated to each pixel.
What is the formula for image file size?
What’s an example of image metadata?
- Creation date
- Width and height of image
- Colour/bit depth
- Geolocation
Where is metadata stored?
In the same file as the image data.
What’s a consequence of storing metadata in an image?
It makes the file bigger.
How do vector graphics work?
Describing images as combinations of geometrical objects.
What is the advantage of vector graphics?
They do not lose quality when scaled.
What is the downside of vector graphics?
It’s hard to represent complex graphics, like a portrait.