Streaming Media Terms and Definitions
affordable church webcasting: Affordable plans and services for Christian churches and ministries to offer free access to audio and video streaming services to their members and potential viewers and listeners.
AVI (Audio/ Video Interleaved): A Microsoft-specified format for saving audio and/or video clips, referred to by Windows as "Video for Windows." You can play the files through the Media Player in Windows or through many popular browser plug-in multimedia players.
bandwidth: The amount of data that can be transmitted in a fixed amount of time. For digital devices, the bandwidth is usually expressed in bits per second or bytes per second. For analog devices, the bandwidth is expressed in cycles per second, or Hertz (Hz).
bit: The unit of information. A computational quanity that can take on one of two values. The smallest unit of storage - sufficient to hold one bit. It is the answer to a yes or no question or in terms of digital data a 0 or a 1.
bit rate: The speed at which data travels from one place to another on a computer network, such as the Internet.
broadband: Used to describe a network connection which supports a relatively high bit rate. Also used to describe content which takes advantage of a high bit rate connection.
buffering: Describes a situation which occurs when a streaming media player is saving portions of a streaming media file to local storage for playback. Most streaming media players buffer a small percentage of a streaming media presentation before beginning to play it. Buffering also may occur in the middle of a presentation, when available bandwidth does not match the presentation's required bandwidth.
capture: Process of digitizing audio and video content from an analog format.
christian podcast hosting: Hosting of and programming of audio files for podcasting files to be included in the iTunes directory as well as made downloadable. Possible income generator for churches and ministries.
christian podcasting: Podcasting or streaming of Christian content through the use of iTunes or through their own website via custom programming and links. This service is an on-demand service (not-live) that can be downloaded and played when the listeners choose to do so.
church audio & video streaming: Audio and video streaming/broadcasting of a church service or event through the internet, viewable and listened via various internet connected devices.
church service broadcasting: Internet broadcasting or streaming of an ongoing church service or event made available to viewers and listeners at home and around the world.
church streaming: Streaming or broadcasting of a church service recording available on-demand (when members and/or visitors are ready to view it).
church webcasting: Internet streaming or broadcasting of church services, sermons, music, special guests, etc., available to others that would like to watch or listen via the internet.
codec (compression-decompression): Standard method of compressing and decompressing data, typically done with audio/video files where data is encoded or compressed to reduce file size. A codec allows an operating system or a program to properly play audio or video in a particular format. Codecs can use software-only or hardware-assisted schemes.
compression: The reduction in the size of data in order to save space or transmission time. Compression is performed by a program which uses an algorithm or formula to determine how best to compress and decompress the data.
data rate: The rate at which bits of information are transmitted per second.
dial-up access: When computer devices hook up to a network via modem and public phone system on a pay-per-time basis. Usually dial-up connections offer limited bandwidths. The alternative to a dial-up connection is a leased line that offers continuous access at a constant bandwidth to a network.
digital video: Digital video is the key to content when streaming media. Digital video is an alternative way of storing or distributing video. Digital video is usually converted from an analog video source. A digital video signal is represented in '1's and '0's, whereas an analog video signal is represented by a fluctuating voltage signal that is stored on magnetic tape. This difference is similar to the difference between analog audio and digital audio.
digitizing: Process of capturing or "bringing in" audio and/or video (usually analog source tapes such as Beta SP, 3/4, VHS, etc.) into a computer. Digitizing is made possible by video hardware, a computer hardware card, cables, and a software application that all work together to convert the original signal into digital media. This digital media can then be edited and transferred back to numerous formats for Internet streaming, CD-Rom, DVD, and other forms of distribution.
DSL: A general acronym relating to Digital Subscriber Lines. The two main types of digital subscriber lines are ADSL (Asynchronous) and SDSL (Synchronous). DSL technologies use sophisticated modulation schemes to pack data onto copper wires. They are also known as 'last mile' technologies because they are used to connect only between telephone switching stations to a home or office, not between switching stations.
encoder: A hardware or software application used to compress audio and video signals for the purposes of streaming.
Flash Media Streaming: Streaming of Flash Audio/Video files or a feed via hi-speed Flash Media Server.
FPS: Frames per second
frame rate: The number of frames of video displayed during a given time -- usually measured in seconds. Standard television video is almost 30 Frames Per Second (fps).
iTunes podcasting: Christian podcasting on iTunes brings your message to a larger audience by having your podcast indexed, searchable and available through the Apple Store. With iTunes, your audience has the tools to manage their listening experience, podcast selection and management.
kbps (Kilobits per second): The rate at which data is sent over a communication line. The typical household modem runs at 56.6 kpbs.
live Christian streaming: Internet streaming or broadcasting of live video and/or audio of a Christian church service, Christian event, Christian conference, Christian music, or any other event that one would like to make available for viewers on the internet.
live church: An internet video or audio broadcast of a Christian church service, live, as it is going on. Social ability to exchange comments, questions, or help promote can be achieved through media outlets such as Twitter, Blog, and Facebook.
live church streaming: Live streaming or broadcasting of a church service as it is happening. This is usually a big benefit for those church memembers that are unable to physically be at the church location but would like to observer the service. This includes, but not limited to military, disabilities, injuries, sickness, out of country, and on vacation.
lossy compression: An encoding or compression method that eliminates redundant and unnecessary data in a file in order to compress it more tightly.
Mbps (Millions of bits per second): It is a measure of bandwidth. A unit of information transfer rate. While an ethernet connection can run at 10 Mbps the average household modem still runs at 56.6 kbps (kilobits per second).
MP3: MP3 is the MPEG audio layer 3 standard. Layer 3 is one of three coding schemes (layer 1, layer 2 and layer 3) for the compression of audio signals defined by the MPEG committee. Layer 3 uses perceptual audio coding and psychoacoustic compression to remove the redundant parts of a sound signal. It also adds a MDCT (Modified Discrete Cosine Transform) that implements a filter bank, increasing the frequency resolution 18 times higher than that of MPEG audio layer 2.
MPEG: MPEG is a digital video and audio compression format that was defined by the Moving Pictures Experts Groups which is part of the International Standards Organization (ISO). MPEG is a lossy compression method which uses Interframe compression. Interframe compression assumes that although action is happening, the background in most video frames remains the same. This means that it is not necessary to compress each entire frame, but only the differences between them. The Interframe method compresses three types of frames: I-Frames, P-Frames and B-Frames.
MPEG-4: MPEG-4 defines how multimedia streams – video, audio, text, data – are transmitted as individual objects. MPEG-4 is a compression/decompression technology that aims to achieve interactivity, efficiency and stability in narrow-band transmissions. On a broader level, MPEG-4 aims to pave the way toward a uniform, high quality encoding and decoding standard, that would replace the many proprietary streaming technologies in use on the Internet today. MPEG-4 is also designed for low bit-rate communications devices, such as mobile receivers or wristwatches that can display video. These devices are usually wireless and can have different access speeds depending on the type of connection and traffic. To overcome this problem, MPEG-4 supports scalable content. Content is encoded once and automatically played back and transmitted at different rates, depending on the available network connection.
multicast: A process which allows a server to send one stream to multiple recipients. This is different from traditional streaming media, where each user connects separately to a server.
multimedia: The integrated presentation of text, graphics, audio, video and animation, mostly on computers.
net congestion: Describes a situation that occurs when there is some significant and unexpected delay between the server's transmission of bits and the client's reception of them.
NTSC (National Television Standards Committee): A set of standard protocols developed in 1953 for the broadcast/ reception of television signals within the United States. It has remained the same since its inception except for the addition of new parameters for the color signal. NTSC scans 525 lines in each image.
on demand: Programming that is available when you want it, instead of when a broadcaster wants to send it.
packet: A chunk of data organized in a block for transmission over an IP network. Usually contains header information with origin and source address, and employs error-correction.
packet loss: Any delay or loss of packets in a transmission, usually caused by a slow or congested network. Packet loss causes breaks or hiccups in data, resulting in audio gaps or video distortion.
PAL (Phase Alternation Line): The standard protocol for television broadcast/reception used in Europe. PAL scans the video image 625 times horizontally.
Podcast (Christian Podcasting): A podcast is a digital media file, or a series of such files, that is distributed over the Internet using syndication feeds for playback on portable media players and personal computers. A podcast is a specific type of webcast which, like 'radio', can mean either the content itself or the method by which it is syndicated; the latter is also termed podcasting. The host or author of a podcast is often called a podcaster.
Podcast Hosting (Christian Podcast Hosting or Christian iTunes Hosting): iTunes does not host or cache podcast XML or media files. Podcasters host their own media files and RSS feeds on their own web servers, or by contracting with a 3rd party for hosting provider. The iTunes Store houses a searchable directory of podcasts, to which your podcast feed can be submitted.
progressive download: A method of delivering audio/video data over the Internet that involves playing the downloaded portion of a file while the download is still in progress. Also referred to as "Pseudo-Streaming".
QuickTime: Multimedia architecture used by software tool vendors and content creators to store, edit and play synchronized graphics, sound, video, and music.
RealAudio: Describes a file format for audio-only streaming media technology released by RealNetworks, a leading streaming media platform vendor.
RealFlash: Describes a Flash presentation synchronized with a RealAudio soundtrack, playable in RealNetworks client software.
RealMedia: Brand name describing file formats, server software, player software, and protocols used by streaming media systems from RealNetworks, a leading streaming media platform vendor.
RealVideo: Describes a file format for audio/video media released by RealNetworks, a leading streaming media platform vendor.
streaming media: Streaming media technology enables the real time or on demand distribution of audio, video and multimedia on the internet. Streaming media is the simultaneous transfer of digital media (video, voice and data) so that it is received as a continuous real-time stream. Streamed data is transmitted by a server application and received and displayed in real-time by client applications. These applications can start displaying video or playing back audio as soon as enough data has been received and stored in the receiving station’s buffer. A streamed file is simultaneously downloaded and viewed, but leaves behind no physical file on the viewer's machine.
streaming media hosting: In order for your audio/video streams to be available 24/7 on the web, your multimedia files need to reside on a server. Since these files can be quite large in size, streaming media hosting takes that into account by providing ample storage space and bandwidth so that your viewers are able to receive your broadcast in the highest quality possible.
T1: A very common digital leased-line connection capable of carrying data at 1.544 Mbps.
T3: Similar to a T1, but can carry data at 44.736 Mbps, equivalent in bandwidth to 28 T1 lines.
unicast: A process which forces each individual user to make an individual connection to a server to receive a stream.
video compression: The process through which a complete video file is reduced in size. Video Compression algorithms take advantage of the fact that there is minimal difference from "one" frame to the next. The first frame is encoded and then the sequence of differences between frames. This is also known as "inter-frame" coding or "3D coding"
video on demand (VOD): Describes video content which may be viewed by the end-user from beginning to end, at any time.
video service provider (VSP): Video Service Providers are analogous to Internet Service Providers (ISPs) except that they specialize in providing multimedia storage and streaming services for Internet sites. In this scenario, when a company offers streaming applications on their Internet site, clicking on the video or multimedia file will transparently connect users to the Video Service Provider that stores and streams the content.
WAV (Wave Form Audio): Files with the .wav extension are digital representations of sound and typically take up a good deal of space to store (typically 50MB for a 5 minute song, for instance). If you use software to rip files from an audio CD, it is usually stored in .wav format. Standard Windows sounds are also stored in .wav format.
webcast: (v) The act of webcasting. (n) An individual program which has been, will be, or is being webcast.
webcasting: A live broadcast format over the World Wide Web (WWW).
Windows Media: The streaming media platform released by Microsoft.
Windows Media Audio (WMA): Describes an audio file format associated with the Windows Media platform.