Module 1-Digital Content

Phoneme

A basic sound unit, such as "reh" or "gay".

Bitmap Graphic

A computer graphic that is composed of a grid of tiny rectangular cells.

Container Formats

A data format that holds compressed video streams and compressed audio streams.

Photosites

A grid of tiny light-sensitive diodes.

Analog Data

Represented using an infinite scale of values.

Kilo-

2^10 (1,024) bits or bytes

Mega-

2^20 (1,048,576) bits or bytes

Giga-

2^30 bits or bytes

Peta-

2^50 bits or bytes

Exa-

2^60 bits or bytes

Bit

A 0 or 1 used in the digital representation of data.

Binary Number System

A base 2 number system that represents numeric data used by digital devices.

Pixel

A cell within a bitmap graphic.

American Standard Code for Information Interchange (ASCII)

A code that requires seven bits for each character.

Lossless Compression

A compression method that is able to reconstitute the data into its original state.

Lossy Compression

A compression method that throws away some of the original data during the compression process.

Motion Graphics

A computer graphic that has movement involved, such as a video or animation.

Analog-to-Digital Converter (ADC)

A device that samples analog sounds and converts them into digital data.

MPEG (Moving Picture Experts Group)

A family of highly compressed container file formats and codecs for digital multimedia; MPEG-1, MPEG- 2, and MPEG-4.

Ogg Vorbis

A free audio format that uses lossy compression. It is currently supported by some browsers and is a part of Google's WebM format.

Anaglyph

A graphic composed of two images, one that is tinted red and the other that is tinted blue.

Portable Network Graphics (PNG)

A graphics format designed to improve on the GIF format. This format can display up to 48-bit True Color and uses lossless image compression methods.

Graphic Interchange Format (GIF)

A graphics format that was especially designed to create images that can be displayed on multiple platforms, such as PCs and Macs. This graphics format supports simple animations as well as using lossless image compression methods.

Joint Photographic Experts Group (JPEG)

A graphics format with built-in compression that stores True Color bitmap data very efficiently in a small file. This graphics format uses lossy image compression.

Byte

A group of eight bits.

Rectilinear Projections

A map projection that is viewed within a two-dimensional space, typically a long horizontal photo.

Cylindrical Projection

A map projection that produces a 360-degree image similar to the view of a merry-go-round.

Image Stitching

A method of creating panoramic images by combining two or separate photographs that have overlapping edges.

Run-Length Encoding (RLE)

A method of lossless compression where it replaces a series of similarly colored pixels with a binary code that indicates the number of pixels and their colors.

MOV (QuickTime Movie)

A multimedia file format, popular for digital videos, that works with QuickTime software.

File

A named collection of data that exists on a storage medium, such as a hard disk.

Ogg Theora

A non-proprietary container format (Ogg) and video codec (Theora).

Digital Compositing

A photoediting tool that uses clipping paths and alpha blending in order to assemble multiple images into one.

Optical Character Recognition (OCR)

A process that interprets individual characters during or after a scan.

Charge-Coupled Device (CCD)

A small sensor that a digital camera's lens focuses light onto in order to create a photographic print.

Audio Player

A small standalone software application or mobile app that offers tools for listening to digital audio and managing playlists, but may not provide tools for making your own recordings.

Extended American Standard Code for Information Interchange

A superset of ASCII that uses eight bits for each character.

Alpha Blending

A tool that alters the pixel colors where the edges of an object and the background meet.

Clipping Path

A tool that cuts an object out of an image and knocks out the background to make it transparent.

Digital Video

A type of motion graphics that uses bits to store color and brightness data for each video frame.

AVI (Audio Video Interleave)

A video file format, developed by Microsoft, that was once the most common format for desktop video on the PC.

Audio Interface

Accepts input from a standalone microphone and feeds it into a computer.

Free Lossless Compression Codec (FLAC)

An audio format of excellent sound quality that uses lossless compression. It is supported on many devices as well as being open source.

MP3 (MPEG-1 Layer 3)

An audio format with good sound quality that uses lossy compression. This audio format can be streamed across the web.

Advanced Audio Coding (AAC)

An audio format with very good sound quality based on MPEG-4. This format uses lossy compression and is generally used for iTunes music.

Image Histogram

An interactive graph that can be used to adjust the colors in a digital photo.

File Name Extension

Can be appended to the end of a file name after a period.

Character Data

Composed of letters, symbols, and numerals that are not used in calculations.

Numeric Data

Consists of numbers that can be used in arithmetic operations.

Interlaced Scan

Each frame is drawn by every other line, then its goes back and fills the in-between lines, usually denoted with an "i".

Progressive Scan

Each frame is drawn line by line in sequence from top of the image to bottom, which is usually denoted with a "p".

Frame

Each image within a vector animation.

Cloning

Employs algorithms that pull pixels from one area of an image and then applies them to another area.

Real-Time Rendering

Fills in wireframe objects and generates bitmap images as the action unfolds. Rendering occurs in real time as the computer turns the vector instructions into points of light on the screen.

Keyframe

Frames that depict the beginning and end points of action.

3D Graphics

Graphics based on vectors stored as a set of instructions describing coordinates for lines and shapes in a three-dimensional space.

Game Engine

Graphics software that allows developers to create interactive video games and educational modules.

Resolution Dependent

Graphics, such as bitmaps, in which the quality of the image is dependent on the number of pixels constituting the image.

Computer Graphics

Images created using computers and stored in digital formats.

Intraframe Compression

In a digital video, compression that takes place within a single frame, similar to the compression used for still images.

Compression Ratio

Indicates the ratio of compressed data to noncompressed data.

ASF (Advanced Systems Format)

Microsoft's proprietary container format for streaming digital multimedia; typically holds WMV and WMA files.

Digital Audio

Music, speech, and other sounds represented in binary format for use in digital devices.

ASCII Text

Plain, unformatted text that is stored in a so-called "text-file".

Inpainting

Reconstructing lost, unwanted, or deteriorated areas in a photo.

Audio Compression

Reduces the size of a sound file by removing bits that represent extraneous noise and sounds that are beyond the frequencies of normal hearing.

Image Compression

Refers to any technique that recodes the data in an image file so that it contains fewer bits.

Data

Refers to symbols that represent people, events, things, and ideas.

Data Representation

Refers to the form in which data is stored, processed, and transmitted.

Digital Audio Extraction

Refers to the process of importing tracks from a CD or DVD to your computer's hard disk. Sometimes it is informally referred to as ripping.

Live Stream

Sends media from a server to your local device, where it is played, but not stored.

On-Demand Stream

Sends the media to your local device, where it is stored temporarily, or "buffered" until there is enough data to begin playback.

Interframe compression

Shrinking the size of a video by removing redundant data that is the same in two successive frames.

Delimiter

Signals the beginning and end of a formatting command.

Audio Plugin

Software that works in conjunction with your computer's browser to manager and play audio that you are accessing on a webpage.

Musical Instrument Digital Interface (MIDI)

Specifies a standard way to store music data for synthesizers, electronic instruments, and computers.

MIDI Messages

Specifies the pitches of a note, the point at which the note begins, the instrument that plays the note, the volume of the note, and the point at which the note ends.

Digital Data

Text, numbers, graphics, sound, and video that have been converted to discrete digits such as 0s and 1s.

Image Resolution

The dimension of the grid that forms a bitmap graphic.

BMP

The native bitmap graphics file format of Microsoft Windows. This format supports True Color, but is generally too large in order to be sent as an email attachment. It is generally unsupported by web browsers, so it is not used on the Web.

Bit Rate

The number of bits that are processed during a specific unit of time, usually during one second.

Color Depth

The number of colors available in a graphic.

Frame Rate (fps)

The number of frames that are displayed per second.

Sampling Rate

The number of times per second that sound is measured during the recording process.

Digitization

The process of converting information, such as text, numbers, photos, or music, into digital data that can be manipulated by electronic devices.

Download

The process of copying a file from a private network or Internet server to a local device.

Rendering

The process of covering a wireframe with surface color and texture.

Pixel Interpolation

The process of creating new pixels by averaging the colors of nearby pixels.

Pre-Rendering

The process of rendering vector-based frames and packaging them into a digital movie file.

Rasterization

The process of superimposing a grid over a vector image and determining the color depth for each pixel.

Aspect Ratio

The proportional relations between the width and height of an image or video frame.

Binary

The representation of two states, such as off-on or 1-0.

Codec (compression/decompression)

The software that compresses a video stream when a video is stored, and decompresses the file when the video is played.

Ray Tracing

The technique for adding light and shadows to a 3D image.

File Format

The type of data in a file and the way it is encoded.

Computer Generated Imagery (CGI)

The use of computer-based graphics to create realistic characters and scenery for films, video games, and other motion graphics.

RGB Color Model

The use of red, green, and blue light that can be combined to create the full spectrum of colors.

RAW

These image formats contain the unprocessed pixel data generated directly by a digital camera's sensor.

Digital-to-Analog Converter (DAC)

Transforms digital bits into analog sound waves and outputs them through speakers.

Pixelation

When an image develops an undesirable jagged appearance due to increasing the size of a bitmap graphic.