Textual information – Information expressed in written or printed form using natural and formal languages.
Encoding text information on a computer
When you click a button on the keyboard, a sequence of electrical impulses is transmitted to the processor, the processor processes this sequence and transmits it to the program where you are working, and this program performs an abortion according to the decryption rules.
using binary code
Table ASCII (in hexadecimal or decimal)
(2 bytes are given per symbol)
Encoding graphical information
An analogous and discrete way to present graphical information
The analogical view is a view in which the lines are continuous, as if we were drawing a circle with a chalk, and the discrete view is a view in which everything is made up of points.To make the analogical invention discrete, you need spatial discreteness.To break the continuous lines into separate points, and the more points, the clearer the invention.
A monitor’s spatial resolution – the number of pixels that make up the image on its screen.
Transmission colour systems
RGB/CMYK
RGB – in direct light
CMYK – reflected light
to transfer an image from computer to paper using these two systems, with RGB on digital and CMYK on paper
each point is a pixel, and there are 3 “bulbs” (RGB) in the pixel, depending on whose occupancy we see different images.
there are also so called “Bicked pixels“, if you see a dark spot on the monitor screen that does not disappear when working with different programs, it is a “bicked” burnt out pixel
Encoding audio information
What is sound anyway? – they are elastic waves that propagate in an elastic medium and cause mechanical oscillations in it.
Amplitude – sound intensity
Frequency – pitch
Wave – is an analogue of a continuous line that can be converted into a discrete graph by measuring only certain regions of the line (waves).
We can now identify 2 parameters, which are the depth of sound encoding (or the amount of information needed to encode a discrete volume) and the frequency of discreteness (or the number of sound volume measurements per second)
Digital video encoding
A video is made up of frames – the frames in turn are alternating images. 1 frame of high resolution weighs 6 mb and 1 minute of video almost 9 gb without compression.
how to optimise images
compression – assumes that adjacent frames are very similar and as if they were on top of each other in order to reduce memory usage.
Answers to questions
A continuous sound wave is broken into what?
Answer: into individual small time segments
What is the minimum object used in a vector graphics editor?
Answer: LINE
How many bytes are in the word “BIT”? And how many bits are in the word “BITE”?
Answer: 3, 32.
Graphic images are converted by spatial sampling:
Answer: from analog form to digital form
The number of colors in the palette (N) and the amount of information needed to encode each dot (i) are related and can be calculated using the formula:
Answer: N = 2 to the power of i
The sampling rate is the…
Answer: the number of measurements of sound volume levels per second
A code is called:
Answer: a rule describing the mapping of a set of characters of one alphabet into a set of characters another alphabet