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Published by: Larry Bloomfield & Jim
Mendrala
August 28, 2000 Tech Note - 063 ********************************************** forum! We need help, suggestions, etc. Visit us. ++++++++++++++++++ RE: Tech-Notes #62 So then, the way I read this is that the Organizations that they are trying to help (TV Stations?) many of whom subsist off of News can not have any information at all in that it might get back to the news organization and then be reported on?? This sounds like back when my Dad told me it was hurting him more than me. I am sorry but if the last 30 years of news and news gathering has shown anyone anything it is that if you hide it then it will be uncovered when you do not want it to be and presented in a bad light. Just get out there tell the truth (or your spin on it (though I would rather the truth) and then hope that help will come your way. IF you are a standards body then you need to have all the help you can get to figure out how to fix or improve the standards that you are working on. After all that is what has managed to keep NTSC going for too many years. Rick Lorentson
+ + + + + + From: David A Kasperek dkasperek@hearst.com Like most people who make living in broadcasting and the introduction of HDTV, I share the concerns expressed by most in your newsletter. All of the technical issues in and of themselves are cause for serious concern and we must keep a lot of attention on the developments. However, recently I have changed my opinion of what represents the most serious threat to the successful roll out of HDTV, and ultimately the survival of free, over the air television. I have come to the conclusion that all technical problems, from over the air transmission standards, to set inter operability can and will be overcome. What occurs to me though is that this is a completely irrelevant outcome lacking compelling HDTV programming. There are three stations in this market transmitting HDTV signals. Soon there will be four. A customer looking for a new set in our market however, has no reason to consider an HDTV set, because the Networks provide virtually no compelling programs to watch. As an industry, we provide no benefit to consumers to justify any additional cost for an HDTV set. Ours is a large market with cash flow that can support the additional costs of HD simulcasts. The next wave of markets due for roll out is not that lucky. Does this seem like a problem to anyone else? Dave Kasperek From: Roy Trumbull roy547@email.msn.com There was a recent article in Broadcast Engineering on IOT tubes for digital transmitters that pointed out a rather dismal fact. To allow for the headroom needed for COFDM signals, an existing 8VSB transmitter would have to operate at half the power that can be achieved for 8VSB. A broadcaster faces the need to add 3 dB somewhere. If you really need double the power to replicate coverage, make that 6 dB. This ain’t going to make too many broadcasters happy in places like Resume Speed, Texas. My modest proposal is that when a TV station is sold, that a sales tax of 15% be collected by the government to foster development and maintenance of rural television. An alternative would be that stations in the top 20 markets adopt a smaller market station. In addition, a revenue tax levied against television stations, television networks, cable companies, and DSS operators could be used to foster universal television. Don't laugh. A rural and riled congressman is a sight to see. My prediction: Within 10 years television stations will have to buy the channel they are using. Network HD We were one of the stations that took the
HD feed from the political conventions that was provided by NHK. In our
case, the signal was squeezed into 45 mBits and uplinked. We added three
cans of water to get 1.5 gig back. Then we encoded that locally to 19.4
mBits. The PBS stations took the same signal from NHK but encoded it at
the source as a 19.4 mBit signal that their affiliates could air directly.
That was definitely the “fresh squeezed” version of the program.
Subj: Digital Cinema - What is
it and where are we today?
The movie industry is in for a great change. The definition of what is digital cinema seems to be elusive. For a while it was called electronic cinema. Then, George Lucas announced at ShoWest in Las Vegas, Nevada, in March of 1999 that “Star Wars – The Phantom Menace” would be released in “digital cinema” in June of 1999. And later, towards the end of last year at ShoEast in Atlantic City, New Jersey, the film industry generally agreed that it should be called digital cinema. They didn’t like the term electronic cinema. That sounded old fashioned. Like the new digital sound tracks, the thinking was that this newly-formed idea for distributing films should be called digital cinema. E-cinema was also considered, but it too fell by the wayside as being too close to e-commerce on the internet. With the newer technologies and the need to protect the content, a new system is emerging into what is now being called digital cinema. But just what is digital cinema? It is not a projector, nor is it an HDTV broadcast, nor is it a high definition telecine transfer of some motion picture film, nor is it just a satellite delivery system. It is a whole new system! A system that is really intended to push the state of the art in the exhibition of films. There are six basic parts to the digital cinema system. These parts are essential to replace today’s film distribution technology. These are:
The relative importance of these items depends on who in the industry is being asked. The National Alliances of Theatre Owners (NATO) has indicated that digital cinema must be easy to use. The Motion Picture Association (MPA) has indicated that in addition to cinema quality images, the need for strong security against piracy is high on the list. The major studios would like a cost effective way to preserve or archive the films digitally. The distributors possibly would like more flexibility. All want reliable operation. To date, however, the only thing being
demoed is what could be called a partial digital cinema demonstration.
In the past couple of years, an electronic projection system developed
by Texas Instruments has been exciting the cinematographers and DP’s in
the Hollywood area with the DLP Digital Cinema Projector. It has convinced
many that digital cinema has arrived. The thinking is that the projected
images, when viewed, provide rich colors, good contrast and resolution,
the projector emits enough light to illuminate a cinema size screen, and
that is “good enough” for starters. What is “good enough” is still
being hotly debated today. While the digitally projected images on large
cinema screens might appear to exceed the quality, in several areas, of
35 mm film, it does not
A digital cinema system is really a completely new system made up of many parts. Each part must work and be compatible with other parts of the system. It is not a projector, nor is it a particular transmission system, nor is it a typical television system. The major parts to the system are: · Mastering
The mastering can be broken down into several basic parts. First there is the original scanning of the film to quantize each frame into an RGB data file called a digital source master (DSM). The data file will not be resolution, contrast or color limited and can also accommodate inputs from CGI and some of the new digital cameras. The file not only can be used for archival storage but can also be down-converted to any HDTV or SDTV standard for broadcast via terrestrial, cable or satellite transmission, DVD and the new digital cinema distribution master (DCDM). The DCDM can be plugged directly into a digital cinema projector at the studio for evaluation and approval. The DCDM will be aspect ratio independent and compatible with the digital cinema theatre projectors of the near future. The DCDM then will be passed on to compression. The compression system for digital cinema has not been defined yet. It will either be some form of wavelet compression, Discrete Cosine Transform (DCT) compression such as MPEG, or some variation thereof. The compression system will be of an open architecture so that improvements can be made as time goes by. Since security is very high on the studios’ list, an encryption system that protects the content is a must. In addition to encryption, conditional access is also a key part in the handling of the content. The owners of the content want control over where the films will be shown, when and by whom. Images can not only be watermarked but also fingerprinted so as to identify a particular theatre where a piracy may have taken place. The images and the sound will both be protected. From the output of the compression and encryption, the content will be handed off to the transport or delivery system. Since the content does not need to be transferred in real time, delivery via many forms is being considered. Some favor distribution via satellite or via DVD-R disks. Some favor the Internet or fiber optics. Whatever the delivery method turns out to be, it will deliver the content with no less than 35 mm answer print quality with better color depth, resolution and contrast than is possible by today’s chemical film technology. The audio will accommodate at least twelve channels of uncompressed audio to cover the mono, stereo, 5.1 and 7.1 channels of today, as well as the 10 and 12 channels (or more) of the future. The theatre systems will be automated so that the presentation can be controlled by the film maker where possible and relieve theatre personnel from the chores of projection, changing of lenses, dimming house lights, adjusting screen masking, etc. The last part of the system is projection. Even though the digital cinema projectors of today are “good enough”, new technologies are evolving and the concept of presenting the films’ content with digital light is in its infancy. Higher resolution and wider color gamut are being considered. Higher contrast and possibly brighter images are in the works. Perfect registration of the RGB images and higher frame rates are also being discussed. So, where are we today? Right now there are 17 theatres equipped to show movies digitally onto the cinema screen in the United States, Europe has 11 cinemas and the far East has 3 cinemas for a total of 30 theatres worldwide. What are they showing? Several animated
films such as “Tarzan”, “Toy Story 2”, and “Dinosaur” have been shown in
the United Sates this past year. Photographed films like “Ideal Husband”,
“Bicentennial Man” and “Mission To Mars” have also been shown.
How are they transferring the films? Except for the animated CGI films, all films have been transferred on an HDTV telecine in a Y, Cb, Cr format to an HDTV D-5 tape machine. With the animated CGI films the individual frames are down converted to HDTV and recorded on an HDTV D-5 tape machines These master tape are then played back and color corrected for the TI DLP display by projecting the images from the HDTV D-5 tape machine through digital color corrector using the TI DLP digital cinema projector and comparing it to a film print projected of the same film and re-recording the color corrected images onto another HDTV D-5 Tape machine. The color corrected HDTV D-5 is then played back and compressed using QuVis QuBit server, a proprietary wavelet compression system. The data is then transferred to DVD-R disks and shipped to the theatres. At the theatre the DVD-R disks are loaded and the data transferred to the hard disk(s) in the QuVis QuBit server at each theatre. It is said to take a couple of hours to load an 90-minute film with some additional movie trailers. The audio is uncompressed 5.1 channel sound. The interface to the projector is through a SMPTE 292 protocol. So far the demos have been equivalent to HDTV at 24 frames per second but with less than HDTV resolution. The resolution of the TI DLP cinema projector is only 1,280 x 1,024. The 1.25:1 aspect ratio of the projectors three Digital Micromirror Devices (DMD) is unsquezed by projecting the image either through a 1.5 anamorphic lens for the 1.85:1 aspect ratio films or through a 1.9 anamorphic lens for the 2.35 scope format. The results is that the projected pixels are rectangular, wider than they are high. Depending on where one sits in the theatre one could see the pixels or not. If the theatre is shoebox shaped and deep allowing for viewing the screen from 3 or more screen heights than the pixelization tends to disappear for the average person but if the person is sitting at less than 3 screen heights than the pixels start to show up especially on the titles. This is partly because the titles are generally digitally generated and are rock steady. In Atlanta, Georgia on June 6, 2000 the digital cinema premiere of Twentieth Century Fox's “Titan A.E.” took place. This was the worlds first digitally transmitted movie using a coast-to-coast broadband IP (Internet Protocol) network provided by Qwest Communications International Inc. and was powered by Cisco Systems. The movie was delivered from Qwest's CyberCenter in Burbank, California to the Woodruff Arts Center in Atlanta for its premier showing at Supercomm 2000, 10days before the films scheduled release. The system used to digitally distribute and screen the movie, included a Cisco GSR 12000 routers, Cisco 7140 series VPN routers, Cisco content networking services, Barco/Texas Instruments DLP projection system, QuVis QuBits server, Sigma Designs Tørus Compound Curved Screen and Eastern AcousticWorks digital audio sound system. After Titan A.E. was produced and mastered on a Philips DataCine at VidFilm in Los Angeles, Fox captured and encoded the movie into a digital cinema file. The digital file -- 42 Gigabytes in size after compression– was delivered on through an encrypted and secure virtual private network (VPN). The Cisco-based IPSec VPN solution connected the Woodruff Center directly to the Qwest CyberCenter, supporting the transmission of the motion picture at the highest speed commercially available in the marketplace today – OC-192 (10 Gigabits per second). The result was a digital cinema exhibition with picture and sound quality that is comparable to, or in some instances better than, what movie theaters currently are offering today. Most in Hollywood feel that film is not
“broken” and that the motion picture theatre can provide a movie experience
that you cannot get in the home. However with the threat of the new DTV
broadcasts in HDTV it will only be a matter of time when the home will
have its digital cinema theater. Therefore the theatre owners here in the
United States who are operating on a very small profit margin see that
HDTV in the home is a possible threat to their business. They feel that
the movie going experience one gets at the theatre has to be better in
all ways to what one can be received on HDTV in the home. The theatre owners
also want brighter movies, more sound tracks to make the audio more realistic
to the audience. Sharper images with more realistic colors. Better day
to day
The studios want the ability to archive the digital files and be able to down convert to any TV standard as well as distribute movies without fear of piracy. And if the movie is pirated some means of identifying where and at what time the theft took place. The distributor wants to have better control over who and when the contents of the movie can be shown. In conclusion digital cinema is a new industry that is in its infancy. Study groups have been set up since October of 1999 to discuss what features the digital system must have. It will take some time before a real digital cinema system exists. It is unique though, in that it has a clean slate to work from and doesn’t have to comply with any of the existing television standards in use around the world today but will maintain compatibility. The digital cinema system being discussed today when implemented should be capable of improving the theatre experience for the next 50 years or more just like film has been able to do for the past 100 years. Remember digital cinema is an overall complicated system not just a projector in a theatre. ++++++++++++++++++ Subj: Fire in Russian Central
TV Tower Controlled
The fire that broke out in the Ostankino television tower in Moscow on Sunday was successfully localized at 12:32 p.m. (0832 GMT) Monday, according to local media. The fire is unlikely to spread lower than the 63-meter mark, where firemen mounted nonflammable barriers last night, the Interfax news agency cited head of the Moscow fire department Leonid Korotchik as saying. Nonetheless, firemen are pouring liquid into the cable shafts, and a foam attack can be made anytime if needed, he said. "The blaze in the Moscow Ostankino TV tower is generally controlled," Itar-Tass quoted Vyacheslav Mulishin, deputy chief of the national fire-fighting service, as saying at the midday. The situation at the Ostankino television tower had been stabilized by 12:17 Moscow time (0817 GMT) and there is less smoke now, he said, confirming that the blaze will be extinguished in a few hours. "The main efforts are now being concentrated at an altitude of 69 meters," he said. "A water mixture is being applied from base level to 69 meters. In addition, foam is being poured at the same altitude to prevent sparks falling from the coiling of cables in the upper sections from lighting new fires," Mulishin said. He said 32 firefighters were working inside the tower. A total of 220 firefighters from 27 teams are involved in the operation. On the people missing in the fire, Mulishin said "we don't have any new information about" a colonel from the fire-fighting service and two civilian tower employees missing in the fire- fighting, one of them a woman elevator operator. Earlier, Moscow fire-fighting department chief Leonid Korotchik told the press that firefighters on the TV tower had failed to put out the fire at an altitude above 71 meters. The fire was allegedly caused by a short circuit at the transmitter of a paging company on Sunday afternoon, but the authorities have not officially ruled out the possibility of sabotage. After the outbreak of the fire, Moscow police received an anonymous call that said a bomb had planted in the TV tower and that it would explode shortly, Interfax reported, quoting a source with law enforcement agencies. The Ostankino TV and BC center, inaugurated in November 1967, is the second tallest freestanding building in the world, just after the TV tower in Toronto, Canada. Weighing more than 55,000 tons, the structure is 540 meters tall. Visitors can reach the observation deck at 337 meters in 58 seconds by the elevator. ++++++++++++++++++ Subj: XETV-DT?
Communicator readers have been asking for the official call sign of XETV's DTV station on Channel 23 in Tijuana, Mexico. According to the FCC's CDBS database, the call sign is XETV-DT. According to the instrument of authorization granted by the SCT in Mexico City, the call sign is XETV-DTV. The call sign is not XETV-TD ("television digital," putting the adjective after the noun as is common in Spanish), as some had speculated. ++++++++++++++++++ Subject: In U.S., Digital Haves
Outnumber Have-Nots
(The Washington Post Via Edupage) The Internet continues to integrate itself into the day-to-day routines of Americans, according to the results of a random telephone survey of 65,000 Internet users by Nielsen NetRatings. U.S. home Internet penetration reached 52 percent in July—the first time more than half of all Americans had home Web access. Home access rates jumped 35 percent from July 1999 to July of this year, from 106.3 million home users to 144 million users. Likewise, the time Internet users spend online is going up. The average Internet user spent 9 hours 41 minutes online this July compared with 7 hours and 39 minutes last July, an increase of 26 percent. Internet users are also looking at fewer Web sites, meaning that larger sites are successfully leveraging their brand to hold users' attention. Cheaper Web access is enabling Americans to go online in ever-increasing numbers, says NetRatings' Sean Kaldor. (Washington Post, August 24 2000) ++++++++++++++++++ Subj: Observations of a Traveler
I am currently in London where DTV receivers are flying off shelves because they are given away FREE if consumers subscribe to "wireless" cable service starting as low as $10.50 per month for a one year obligation. Talk about eliminating the digital divide! Over 800,000 DTV receivers were in consumer hands as of July 1st (equivalent figures for the U.S would have been 4 MILLION not the paltry 40,000 delivered to RETAILERS as reported by the Consumer Electronics Association). In fact, sales of integrated DTV receivers and displays in the UK alone have overtaken total DTV receiver deliveries to RETAILERS in the U.S. I have found that a fully integrated DTV receiver, 28-inch 16x9 aspect DTV display with an analog receiver and stereo speakers on an integrated TV stand starts as low as less than $750 (Grundig model MW70/500) and can receive all analog and DTV OTA channels. Contrast this with a MINIMUM investment of approximately $3700 in the U.S. (which does NOT get you the stereo speakers, analog receiver nor the TV stand). LG Electronics, the parent company of Zenith, is selling a similar product (Model # LGE D128Z12), which costs less than $925, if the consumer subscribes to Sky Digital TV for one year (base price is $10.50 per month). BTW, the Sky Digital receiver, dish antenna, and remote are also free, but installation costs $60. Mark E. Hyman, VP, Corporate Relations -- Sinclair Broadcast Group, Inc ++++++++++++++++++ (Ed Note: Feel like linking to an interesting article? We had occasion to read on in Sound & Vision Contractor magazine. The author owns a shop in Doylestown, PA and it looks like he has a pretty good handle on the 8-VSB problems. This is yet another example of how consumer-UNfriendly the current standard is compared to what has been adopted in 31 other countries around the globe. Go to: http://www.svconline.com/ Click on the article: “Video Projections: Distribution of Digital Television Signals” By Peter H. Putman. You may find it interesting, as did we.) ++++++++++++++++++ Subj: MPEG from the Father (Ed Note: The following is the text of a message from Leonardo Chiariglione in answer to questions on MPEG. Mr. Chiariglione is considered by many as the father of MPEG.) In 1997 MPEG decided to develop a standard interface called DMIF, that abstracts the application layer from the transport layer. This has been developed in the MPEG-4 context of which DMIF is part 6. Let me try and explain why DMIF is important for the future of multimedia. If a parcel has to be sent do you care if it is sent over rail, road, air, ship, pony express or a private messenger? - Yes, if you are in the transportation business. If you run a business of parcel haulage by trucks, you would like to be able to do anything with trucks. So for you trucks are the "ideal" way of transporting parcels. - No, if you are the person who just wants the parcel to be delivered. In this case the only things you care about are: how much it will cost, how long it will take and how will be the conditions in which the parcel will be delivered (intact or broken). There are clearly a lot of other elements to be considered but I do not try to list them here. It is only the people with a need to send parcels and the people whose business is to interface with customers in need of sending parcels who can understand which are these other elements. Is the transport of packets of data different? I claim no. As a user I am interested in the conditions with which the packet will be delivered, i.e. - delivery now/delayed,
The position of those advocating the convergence of all transport protocols to IP-based is understandable. The fact that in this imperfect world such a convergence is bound to bring considerable benefits to the industries more engaged in the deployment of IP-based products and services is even more understandable. Do I have a problem with the former? Yes. If it is true that in an environment of unlimited bandwidth the way the transport layer is actually configured is almost irrelevant, and therefore the protocol with the more features is the right choice, in this bandwidth-limited world of today the actual shape of the transport protocol is terribly important. On a case-by-case basis one may decide that what is lost in guaranteed delivery of one protocol is compensated by the more functionalities of the other. Advocating a convergence tout court now to IP is unrealistic. Do I have a problem with the latter? Not at all. Simply, as you say in English (with a personal modification): been there, seen that. For an industry, trying to grab as much market share as possible from other industries is a natural thing to do. But while I think that trucks are a great transport systems, I would not like the air transport system or the ship transport system to be put out of business, because there are clear cases where truck transportation is no match to air or ship transportation and I have an interest in keeping my options open. Instead of bending a transport protocol to do what it has not been designed to do, let us use each protocol for what it has been designed for. True, in order to do that, we have to create an intermediary that did not exist before, one who manages the allocation of each packet to the transport mechanisms that does the best job. Better this intermediary, however, than being forced through one's throat a transport protocol that is unsuitable for a particular job. It would be ironic if something rational that is happening in the physical world (just think of the many transport systems FedEx uses) would not have anything corresponding to it in the virtual world, while the virtual world is supposed to be the kingdom of Reason, or not? Let me now address another mantra, i.e. video content joining the Internet. I have a problem here and not because video on the Internet is not good (depending on what you want to achieve this is great), but because we are confusing content with transport. To use the same example as before, I do not consider a letter as a part of the postal service. It is a letter that I want to get delivered somewhere and for that purpose I may decide to use the postal service transport, but I may as well use a courier service or have the letter hand-delivered through a trusted person. Is my letter part of the courier service or of the trusted person? Not at all. So, please, don't let's confuse content with transport. They are two different things. One is the end and the other the means. There is a world of content and there is a world of transport. Let people holding content or the people in need of content choose the transport that suits their needs. And not vice-versa, please. Leonardo Chiariglione ++++++++++++++++++ YOU JUST MIGHT BE A RF ENGINEER IF YOU/YOUR:
Can remember 7 computer passwords but not your anniversary, (or ANY of your wife's clothing sizes).
The Tech-Notes are published by Larry Bloomfield and Jim Mendrala. We can be reached by either e-mail (above) or land lines (408) 778-3412, (661) 294-1049 or fax at (419) 710-1913 or (419) 793-8340. The opinions expressed herein are those of the individual authors and do not necessarily reflect the opinions or positions of their friends, employers or associates. If you wish to remove yourself from this list, send an E-mail to: hdtvguy@garlic.com. In the subject area put the word Remove. Please visit our web page to review our policies and to see any additional information. www.Tech-Notes.net END |