HOME PAGE
About the WYSHS
Committees
Membership
Chapters
Annals of Wyoming
Wyoming History News
Events
Projects
Awards Program
Homsher Endowment
Publications
Artwork & Photos
Historical Foundation
Friends of the WYSHS
Museums
Historic Sites
Other Resources
Best of the WEB
Just For Fun Pages
Contact Us
What's New
Search this site or the web:

 WYSHS Site search
 Web search
Join our Mailing List
 To be automatically
notified via email
of web site updates:
 subscribe
 unsubscribe
Wyoming State Historical Society
Just For Fun Pages
Digital History Theater
Additional Video Playback Information

PLEASE NOTE:

Backup your files and review your system documentation prior to making any changes to your computer. Search within your documentation for configuration guidelines. Many graphics cards, hard drives, and systems come with recommendations for optimal video performance; again, refer to your documentation.


QUICKTIME FORMAT:

All films are displayed in the QuickTime (with Cinepak compression) format. This format offers smaller, downloadable files and allows films to be viewed on lower-end computer systems. In QuickTime, film quality is not as crisp as .mpg format film (see below). On lower-end, slower-speed computers, QuickTime will drop video frames. The average file size in the QuickTime (Cinepak) format is about five megabytes for each minute of motion picture.

QuickTime 3 (with Sorenson compression), has enhanced image quality and higher resolution. The average file size in QuickTime 3 format is about six megabytes for each minute of motion picture. QuickTime 3 generally requires a high-end, high-speed computer.

QuickTime Player Suggestions:
MPEG FORMAT:

The highest-quality film files are presented in the .mpg (Motion Picture Experts Group or MPEG) format. Films presented in .mpg format are higher resolution and better quality than the equivalent QuickTime versions. To view films in the .mpg format, you should have a high-end, high-speed computer such as a Pentium 90 (or better) with a PCI or AGP graphics card and .mpg playback software, or a PowerMac with .mpg playback software.

An MPEG-1 video playback board or hardware-assisted playback may increase the playback performance of MPEG movies, but it is not necessary for modern computers. The average file size for the .mpg format is about nine megabytes for each minute of film.

MPEG Player Suggestions:


REALMEDIA FORMAT:

RealMedia allows viewing of the film as it arrives at the user's computer, eliminating the need to download the film completely before viewing. RealMedia format is especially useful for computers with slower internet connections, such as a 28.8 modem. Video playback is slower (3-6 frames per second) and may be affected by internet traffic. Video quality will suffer and look blocky.

RealMedia Player:
NOTE: To search for freeware or shareware video players on the World Wide Web, use the search words video helper applications.


GENERAL INFORMATION:

Motion pictures longer than four minutes may have been segmented, thereby limiting maximum file size to approximately 40 MB. Please note that a typical 28.8 internet connection achieves a theoretical maximum download rate of approximately 3.5 KB/sec (210 K/min) under ideal conditions. Therefore, a file of 40 MB would take approximately 190 minutes (3 hours 10 minutes) in optimal conditions and more likely much longer (up to 2 to 3 times) depending on internet traffic load.


DIGITAL FORMAT COMPARISON CHART:

Format File Extension Pixel Size Width/Height Frames per Second Bytes per Second Bytes per Minute Streaming
MPEG .mpg 320 x 240 30 fps 150 KB 9 MB No
QuickTime
(Cinepak)		 .mov 160 x 120 10-15 fps 80-100 KB 5 MB No
QuickTime3
(Sorenson)		 .mov 320 x 240 15 fps 100 KB 6 MB Yes
RealMedia .ram / .rm 160 x 120 3-6 fps 2.5 KB 150 KB Yes


QUALITY AND COMPUTER REQUIREMENTS:

MPEG (.mpg)

Quality: The .mpg video files are the highest quality digital video files we currently offer.

Computer Requirements: The .mpg files require either an MPEG-1 playback video board (hardware assisted playback), a Pentium 90 or better (PC) with a PCI or AGP graphics card and .mpg playback software, or a PowerMac (Mac) with .mpg playback software.

QuickTime (.mov)

Quality: The QuickTime files using the Cinepak codec (COmpression and DECompression) are provided to offer the user a smaller downloadable file and playback on slower machines. However, the video quality is not as crisp as MPEG.

Computer Requirements: The minimum computer needed is a 386/20Mhz (PC) or a Mac LC III. The computer must have enough hard disk space to download the video file. A local bus (PCI Recommended) graphics card with a minimum of 32,000 (15 bit) color support at 640 x 480 screen resolution and video acceleration capability. Performance may be compromised when using the minimum system configuration.

QuickTime 3 (.mov)

Quality: QuickTime 3 supports the Sorenson codec, as well as Cinepak codec and other codecs. The Sorenson codec provides superior image quality (less distortion of detail). At a given data rate, the Sorenson codec will support a larger image size (pixel width and height) than the Cinepak codec.

Computer Requirements: Because the QuickTime 3 player and Sorenson codec offer the ability to stream video files, speed of the internet connection is important. At the 100KB/s data rate, the end user would need a connection approaching a T1 line. However, even that amount of bandwidth would not guarantee uninterrupted playback of the video because of Library of Congress and internet traffic loads. QuickTime 3 requires at least a Pentium 90 MHz or a PowerMac with at least 16 Megabytes of RAM (random access memory).

RealMedia (.ram / .rm)

Quality: RealMedia, a streaming file format, allows viewing of the film as it arrives at the user's computer, eliminating the need to download the film completely before viewing. Because of extreme file compression and the dependance on speed of the internet connection, RealMedia videos will not have smooth fluid motion in high action sequences. Video quality will suffer and look blocky at a 160 x 120 pixel size because of the extreme compression ratios (approximately 650:1 versus an uncompressed 160 x 120 30 fps video file) achieved through the RealEncoder.

Computer Requirements: RealMedia video requires a minimum of a 28.8 modem connection to the internet, 486/66 computer using RealMedia 5.0, or a Pentium 120 using RealMedia G2. The RealMedia video will stream to the computer at approximately 3 to 6 fps (dependent upon internet traffic).


PLAYBACK PERFORMANCE FACTORS:

There are a number of factors that could result in poor playback performance of these digital video files. If your system does not meet the minimum specifications, video playback may result in degraded performance, i.e., dropping of video frames resulting from playback displaying less than the standard 30 fps.

Software settings - Ensure your software is optimally configured for your hardware. Close all other programs prior to playing a digital video file. If you are using a PC, you should be running Windows 3.1 or later. For Macintosh computers, System 7.5 or later is recommended. Some digital video players have a method for configuring video playback. Refer to the software's web site help file or readme file.

System Maintenance - Backup your system files and defragment the hard drive regularly. If your hard drive is fragmented, video playback performance could suffer by looking disrupted and jerky.

Please contact us with your comments, suggestions or inquiries.
Web Services provided by:
NewERAnet.com
Privacy Policy
HTML ©Copyright 2000-2001 Wyoming State Historical Society