Comparison Charts and descriptions of the most Commonly used video and image file formats

Video Streaming vs. Downloading
Video Streaming	Streaming is the transfer of data in a continuous stream over the Web (usually audio or video) that allows the user to play it as it arrives. To receive this content, you must have the right plug-in for the application, such as RealPlayer, QuickTime viewer, etc. A method for transferring data continuously. Streaming allows you to display the data on your browser before the entire file is transmitted.
Downloading	To transfer (data or programs) from a server or host computer to one's own computer or device. Allows media to be played quicker because it is downloaded to ones computer.

Most common Video file formats compared

Video File Format	Characteristics
ASF,WMV (Advanced Streaming Format) (Windows Media Video)	Can be streamed across the Internet and viewed before entire file has been downloaded when using a Windows Media server. Requires Windows Media Player be installed on client. Typically placed on an internet streaming server.
AVI (Audio Video Interleave)	Can be viewed with standard Windows Players such as Windows Media Player. Uncompressed yields a high quality video but uses a lot of storage space. If downloading from the Internet, the entire file must be downloaded before being played. Typically stored on local hard disk or CDROM or made available as download from web server.
MOV (Apple Quicktime Movie)	Requires Apples Quicktime Movie Player Depending on Compression chosen can provide a very high quality video clip, but better quality uses more storage space. Can be streamed across the Internet and viewed before entire file has been downloaded if using a Quicktime streaming server. Can be placed both on an internet streaming server, or local storage such as hard disk or CDROM.
MPEG (Motion Pictures Experts Group)	Can provide VHS quality movies or better Mpeg1 is equal to VHS. Mpeg2 is better than VHS and used for DVD Mpeg4 is being developed Requires an MPEG player to view If downloading from the Internet, the entire file must be downloaded before being played because files sizes are very large. Typically MPEG1 is used to make a one hour VCD movie. Typically MPEG2 is used to make DVD movies, but can be used to make about a 30 minute high quality VCD. Can be placed on any storage media large enough to hold the file, but at current time the internet speed will not support streaming MPEG files. Any MPEG files found on the Web will have to be downloaded to the local drive and played using an MPEG player.
RM (Real Media)	Can be streamed across the Internet and viewed before entire file has been downloaded when using a Real Networks Streaming server. Has very high compression, but at a cost to quality. Requires Real Networks RealPlayer to view content.

Basic Picture Image file format comparison

This chart is particularly helpful when wanting to place an image file on
diskette or a website and the size needs to be small.

The table below illustrates the relative file sizes that can be achieved by the
different file formats in storing a "native" 1MB image, and also indicates the color depth supported:

File format	Image size	No. of colors
BMP - RGB	1MB	16.7 million
BMP - RLE	83KB	256
GIF	31KB	256
JPEG - min. compression	185KB	16.7 million
JPEG - min. progressive compression	150KB	16.7 million
JPEG - max. compression	20KB	16.7 million
JPEG - max. progressive compression	16KB	16.7 million
PCX	189KB	16.7 million
TIFF	1MB	16.7 million
TIFF - LZW compression	83KB	16.7 million
PNG - file format will compress files at a similar ratio to jpeg, except unlike jpeg, resaving an image will not degrade its quality. Where possible PNG should be the file type of choice.

Material adapted from SAMM – Students Achieving with Multimedia Class