COMPSCI TEXT SOUND N IMAGE

• Text can be represented in binary, which is the language that computers use to process information
• To represent text in binary, a computer uses a character set, which is a collection of characters and the corresponding binary codes that represent them
• The American Standard Code for Information Interchange (ASCII) is a commonly used character set that assigns a unique 7-bit binary code to each character, including uppercase and lowercase letters, digits, punctuation marks, and control characters
• ASCII does not support characters from languages other than English
• Unicode was developed as a character encoding standard to address the limitations of ASCII, allowing for a greater range of characters and symbols, including different languages and emojis
• Unicode uses a variable-length encoding scheme that assigns a unique code to each character, which can be represented in binary form using multiple bytes
• Unicode requires more bits per character than ASCII, leading to larger file sizes and slower processing times when working with text-based data
• Sound is an analog signal that is captured and converted into digital form to be processed by a computer
• To convert sound into digital form, a process called sampling is used
• Sampling involves taking measurements of the sound wave at regular intervals
• These measurements are then converted into binary data
• The quality of digital sound depends on the sample rate
• Sample rate is the number of samples taken per second
• A higher sample rate results in a more accurate representation of the original sound wave
• A higher sample rate also increases the file size of the digital sound
• E.g. A typical CD-quality digital sound has a sample rate of 44.1 kHz, meaning 44,100 samples are taken per second
• Sample resolution is another factor that affects the quality of digital sound
• Sample resolution refers to the number of bits per sample
• A higher sample resolution results in a more accurate representation of the sound wave
• A higher sample resolution also increases the file size of the digital sound
• E.g. A CD-quality digital sound typically has a sample resolution of 16 bits, meaning each sample is represented by a 16-bit binary number
• It's important to choose the appropriate sample rate and resolution based on the specific requirements of the digital sound application
• A high-quality music recording may require a higher sample rate and resolution than a voice recording for a podcast
• A bitmap image is made up of pixels, which are small dots of colour arranged in a grid
• Each pixel can be represented by a binary code, which is processed by a computer
• Resolution of an image refers to the number of pixels in the image
• A higher resolution image has more pixels, making it sharper and more detailed
• Higher resolution images require more storage space
• Colour depth of an image refers to the number of bits used to represent each colour
• A higher colour depth allows for more colours to be represented, resulting in a more realistic image
• Higher colour depth requires more storage space
• An 8-bit colour depth allows for 256 different colours to be represented (2^8=256)
• A 24-bit colour depth allows for over 16 million different colours to be represented (2^24=16,777,216)
• File size of an image increases as the resolution and colour depth increase
• More pixels and colours require more binary data to represent them
• Quality of an image increases as the resolution and colour depth increase
• It's important to balance desired quality with practical limitations of storage space