Unit 2 - Digital Information
Lesson 2: Text Compression
- Heuristic: a problem solving approach (algorithm) to find a satisfactory solution where finding an optimal or exact solution is impractical or impossible.
- Lossless Compression: a data compression algorithm that allows the original data to be perfectly reconstructed from the compressed data.
- Lossy Compression: (or irreversible compression) a data compression method that uses inexact approximations, discarding some data to represent the content. Most commonly seen in image formats like .jpg.
Lesson 3: Encoding B&W Images
- Image: A type of data used for graphics or pictures.
- metadata: is data that describes other data. For example, a digital image may include metadata that describe the size of the image, number of colors, or resolution.
- Pixel: short for "picture element", the fundamental unit of a digital image, typically a tiny square or dot that contains a single point of color of a larger image.
Lesson 4: Encoding Color Images
- Hexadecimal: A base-16 number system that uses sixteen distinct symbols 0-9 and A-F to represent numbers from 0 to 15.
- Pixel: short for "picture element", the fundamental unit of a digital image, typically a tiny square or dot that contains a single point of color of a larger image.
- RGB: the RGB color model uses varying intensities of (R)ed, (G)reen, and (B)lue light are added together in to reproduce a broad array of colors.
Lesson 5: Lossy vs. Lossless Compression
- Lossless Compression: a data compression algorithm that allows the original data to be perfectly reconstructed from the compressed data.
- Lossy Compression: (or irreversible compression) a data compression method that uses inexact approximations, discarding some data to represent the content. Most commonly seen in image formats like .jpg.