Associazione Centro ELIS has played a relevant technological role in the MUSK project. It has given the English and the Swedish partners technical support needed for achieving the project goals.
It has set up and now runs the MUSK web server, which contains, at the end of the two years period, all the public information for a better dissemination of its project results.
ELIS main activity has been studying and developing an Intranet video server for "Campus Bio-Medico" di Roma, both for the University and for the Faculty of Medicine Hospital.
The following document summarizes the outcome of the two years work. It is both available on CD-ROM and on the MUSK web site (http://projects.elis.org/musk). The general description, the test videos and the conclusions make it a good resource of information for any small and medium enterprise wanting to use streaming video technology for training or education.
In this period ELIS has also produced a number of CD-ROM's containing intermediate results which are also stored in the final site and in the CD. In order to use all the features enabled in the site and in the CD, you have to browse them through Microsoft Internet Explorer 4.01 SP1 or later, using MediaPlayer and RealPlayer G2.
ELIS project leader, Michele Crudele can be contacted via e-mail at firstname.lastname@example.org for any more information or clarification.
We thank Hewlett-Packard for the support given to ELIS through hardware donation. We thank all those that in Campus Bio-Medico University have helped in making this project a success.
The use of this material, text, software, videos, is free for evaluation purposes, provided you mention the author and you respect the original rights of the producers.
February 19, 1999
This set of documents and resources has been produced by Associazione Centro ELIS for "Campus Bio-Medico" di Roma (a University with teaching hospital, in the range of Small and Medium Enterprises - SME), in order to study the implementation of an Intranet delivery system of videotapes on Nursing Sciences, aimed at the continuous education of nurses in the University Hospital and at the initial training of students.
The video server has been set up using Microsoft NetShow Services and is available only in the internal network of Campus Bio-Medico in Rome. In the CD-ROM you can experiment a partial view of the methodology and techniques we adopted. In the MUSK public web site, the same resources are available, but the high encoding at 200 Kbps of the videoclip makes its playback possible only with a very fast Internet connection.
|The scenario of streaming video solutions||Comparing NetShow and RealSystem||The original video files||The hardware||Benchmark table||Software and documentation|
|Introduction||With the development of streaming video technologies,
it is now possible to deliver full quality video over an Intranet and fairly good quality
video over standard Internet lines. Since the use of videotape based material for training
in Small and Medium Enterprises (SME's) is fairly common, streaming video solutions can
overcome the common problem of distribution and availability of videotapes, through the
setting up of a network connected video juke box.
When the Intranet is not available, producing a CD-ROM can prove to be cheaper than a videocassette, because for the same price it can contain dozens of videoclips, depending on the level of compression and quality required.
During the lifetime of MUSK project, new technologies have changed dramatically the digital video market, lowering prices by a factor of 10. Disk storage devices, both hard disks and CD's, are now much cheaper, networks are faster, and software has reached a price/performance level that makes it affordable for any small institution or company. The introduction of DVD will give a further boost, enabling the storage of full educational courses (100 hours and more) on a single digital disk.
The simple digital encoding of existing videotape based training material is therefore easy and cheap. Instead of duplicating videocassettes and providing VCR's and TV sets to all trainees, an SME can use its internal computer network to provide an instant on demand video server. A normal PC with sound capabilities, connected through a LAN, is the only requirement.
More can be done by using the advanced capabilities of streaming video systems: the video clip can be indexed and searched through instantaneously; it can be inserted in a webpage giving additional information about the subject; it can trigger events, automatically linking specific parts to text, graphics and other web based material, such as interactive questionnaires or glossaries. The user gets therefore an added value to the plain videocassette.
Live events can be broadcast using the proper software. This is also a non-expensive solution for delivering a lesson in different sites of the SME, instead of repeating the teaching in all the places or moving all the personnel in one site. Again only a LAN or a fast Internet connection is required to get the best video quality, using a normal computer server.
|The scenario of streaming video solutions||Streaming video is a solution to the download-and-play
problem. When a user wanted to watch a movie over the Internet or any network, he or she
had to wait until the full video file was downloaded. Because video files are
usually very large, the only video found on the world wide web were few seconds long. By
using a client/server architecture, video is displayed to the end user as it streams over
the network in real time. Other than a few seconds of latency at the beginning, there is
no wait associated with watching a video clip, and it doesn't matter how long the clip
lasts. The only important issue for a producer is to create a video file that gives good
quality at the bitrate the user is expected to achieve over his or her network, from 28.8
Kbps modem to a 100Mbit network. The content provider must first decide who will be the
target user. The same technology can be applied to CD based videos, using mainly the high
compression codecs provided by streaming systems.
In 1997 there were a dozen different competitors in the streaming video market. Through acquisitions and withdrawals, Microsoft and RealNetworks now share the full market. There is no clear advantage of one system over the other, and new versions of both are released at a very high rate.
Microsoft - http://www.microsoft.com/netshow - is proposing, through NetShow Services, a complete solution embedded into NT server (starting from NT 4 SP4). The player is now a universal MediaPlayer, shipped with Windows 98 (but available also for Win 95), using many types of codecs. Both NetShow server software and player are free of charge. The need for NT server means that you pay for that operating system. You also have to pay if you choose the Microsoft NetShow Theater Server, a broadcast-quality, full-screen video solution on dedicated high-bandwidth networks.
RealNetworks - http://www.real.com - has more experience, offering through G2 a solution for almost any need (from the amateur to the professional or commercial), with an exceptionally good audio quality and very good video, especially at low bitrate, for many operating systems. The player is free, while the server starts from a free version for 25 simultaneous connections, to quite expensive commercial high-end solutions. The basic encoder is free, which makes it possible for an end user to develop streaming videos and deliver them to a limited public.
For producing a CD-ROM with streaming video content, all the software required is free from both companies. The only hardware needed to record from videotape or from a live source (videocamera), is a supported video capture card (starting from 150 EURO). The complete list of supported video cards for NetShow can be found in http://www.microsoft.com/ntserver/mediaserv/techdetails/techspecs/systemrequirements.asp#video
If you already have AVI files, you do not need any hardware at all.
The MPP project site, run by ELIS (http://projects.elis.org/mpp) contains more information about streaming video.
|Comparing NetShow and RealSystem||In order to be able to assess the quality of streaming
video, you can find below some comparisons of different encoding using Microsoft NetShow
The clips are locally played, which means they are not using any specific server (which gives more features while playing). If you are using this resource from a CD you will get instant results, while if you are browsing these pages using the Internet you will need at least a 128 Kbps connection. This is because our purpose was to evaluate local network systems and not long distance services.
All the data that can be useful in planning a CD or a video server is reported.
The sources are AVI files. We have limited our assessment to high bandwidth coding (over 100 Kb/s) for use over an Intranet or locally from a CD. Using lower rates means reducing the frame rate or the size of the video, which sometimes cannot be performed without losing important details. In that case other solutions, like the one implemented in the MPP project, can be applied.
The original CYCLE.AVI from the English MUSK partner North Trafford College had Microsoft ADPCM as audio codec, which was not suitable for RealEncoder. We first converted it to PCM (CYCLEPCM.AVI).
We first converted the CYCLEPCM.AVI to MPEG-1 which sometimes can be the best solution for CD based very high quality clips. Anyway, by checking all the encoded clips you will realize that RealVideo codecs and MPEG-4 retain sufficient quality, with much less storage needs than MPEG-1.
You have to consider that the quality of the original AVI is not excellent and it does not contain much motion even though it is recorded at 25 frame per second. Therefore we have also used another AVI file (TRAIN.AVI) with better image quality, 15 frames per second but a smooth continuous motion, without audio.
We are aware that audio is a completely solved problem. You can get nearly music stereo CD quality over 20 Kbps connection. For speech, 8 Kbps exceed the needs and 5 kbps are normally sufficient.
Note: do not confuse KB/s (KByte per second - KBps) with Kb/s (Kbit per second - Kbps). One KBps is equal to 8 Kbps.
|The original video files||CYCLEPCM.AVI
: 8,482 KB
30.9 seconds, 320x240, 24 bit, 773 frames, 25 fps, 274 KB/s (2192 Kbps), Cinepak codec, Audio PCM, 11.025 Hz, 16bit, mono
The same clip has been converted to MPEG-1 CYCLEPCM.MPG: 4,659 KB (25 fps) which requires around 1200 Kbps.
TRAIN.AVI : 4,461 KB
The same clip has been converted to MPEG-1 TRAIN.MPG: 1855 KB which requires around 1200 Kbps.
|The hardware||The encoded videos have been produced on a
Hewlett-Packard Kayak with 300 MHz double processor and a Vectra VL 200 MMX. There is no
difference in quality between the two systems, when encoding from files. The only
difference is time, much shorter if the machine is more powerful. In live encoding the
processor plays a relevant role, because it must be capable of sustaining the encoding
speed for the bandwidth required. Anyway, any Pentium II is now good for encoding at 200
Kbps with 320x240 frame size.
We thank Hewlett-Packard for the support given, through the hardware donation to ELIS.
We have collected all the useful software for producing and playing streaming videos, both using Microsoft and RealNetworks tools. The full documents about NetShow can help in deployment. The software, with the latest versions, is also available at the home sites of both companies.
We have also added two important collaboration products: NetMeeting for audio and videoconferencing over the Internet, and America On Line Instant Messenger for real time group text chatting working even with very poor Internet connections.
|Microsoft Internet Explorer 4.01 SP1||download||download||download|
|NetShow MediaPlayer when Internet Explorer 4.01 is already installed||download||download||download|
|NetShow MediaPlayer without IE4.01 (good also for Netscape)||download||download|
|NetShow tools for producing videos from live or files||download|
|NetShow server for Windows NT||download|
|NetShow Software Development Kit||download|
|The File Transfer Service control in NetShow Services (contained in nsfile.ocx). An ActiveX control used to receive files broadcast over the Internet or corporate intranets.||download|
|NetShow - Windows Media Technologies for Web||18/8/98|
|NetShow3 white paper||6/7/98|
|NetShow - Deployment document||20/7/98|
|NetShow - Producer guide to live||6/7/98|
|NetShow - ASF format description||27/2/98|
|RealProducer G2 for producing videos from live or files||download|
|NetMeeting 2.1 for Windows 95 and NT||download||download|
|AOL Instant Messenger 2.0.912||download|
During 1997 and 1998 the assessment done by ELIS produced partial results which are still available.