Data Representation in Data Communication
Data representation is the method by which different types of data (text, numbers, images, audio, video) are converted into a binary format suitable for transmission over digital networks.
Forms of Data Representation
- Text
- Binary Representation: Text data is represented using binary codes, such as ASCII (American Standard Code for Information Interchange) or Unicode.
- Example: The letter “A” in ASCII is represented as 01000001.
- Numbers
- Binary Representation: Numbers can be represented in binary, hexadecimal, or other numeral systems.
- Example: The decimal number 5 is represented in binary as 0101.
- Images
- Pixel Representation: Images are represented as a grid of pixels, each with a binary value indicating color and intensity.
- Color Models: RGB (Red-Green-Blue) model or grayscale for monochrome images.
- Example: A 24-bit image uses 8 bits per color channel (red, green, and blue), allowing for 16 million colors.
- Audio
- Analog to Digital Conversion (ADC): Audio signals are initially analog. Through sampling, quantization, and encoding, they are converted to digital.
- Sampling Rate: The number of samples per second, measured in Hertz (Hz), affects audio quality.
- Example: A CD-quality audio file has a sample rate of 44.1 kHz and a bit depth of 16 bits.
- Video
- Frame Representation: Video is represented as a sequence of frames, each frame being an image.
- Resolution & Frame Rate: The quality of video data is determined by resolution (number of pixels) and frame rate (frames per second).
- Compression: Due to high data requirements, video is often compressed using codecs (e.g., H.264) to reduce file size.