What Happened at Oslo? - ITU Color TV
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What Happened at Oslo?
George H. Brown of RCA (left), and Frederick M. Remley, Jr. of SMPTE (right). Why there isn't worldwide agreement on a color-television system. By Thomas R. Haskett Previous Radio-Electronics articles have discussed color television as proposed throughout the world.* This subject was one of several considered by participants in a conference at Oslo, Norway, during June and July 1966. To find out exactly what was discussed, why it was discussed, and why the conference ended the way it did (Radio-Electronics, October 1966, p. 4), we interviewed two US delegates. Dr. George H. Brown is executive vice president, research and engineering, of the Radio Corporation of America. Long a radio and television engineer, he is the developer of the turnstile antenna, the most widely used television transmitting antenna. Mr. Frederick M. Remley, Jr. is chairman of the Video Tape Recording Committee, Society of Motion Picture and Television Engineers, and technical director of the University of Michigan's Broadcasting Service.
Table I - Color-System Preferences by Country Radio-Electronics: Gentlemen, would you tell us how the Oslo conference came about? Dr. Brown: From time to time, the member countries of the United Nations wish to discuss matters in the areas of radio, television and communications. Routine specialized topics are rarely discussed in the General Assembly, but usually handled by the UN agency responsible for such affairs. The particular agency for radio, television and communications is known as the ITU - International Telecommunications Union. R-E: Then the ITU sponsored the Oslo conference? Definitions ART: Additional Reference Transmission CCIR: International Radio Consultative Committee (UN) NIR: National Research Institute (USSR) NTSC: National Television System Committee (US) OIRT: International Radio and Television Organization (USSR and satellites) PAL: Phase Alternation Line SECAM: Sequential by Memory Mr. Remley: Not directly. ITU is a large organization, involved in many fields of international communications. One of ITU's divisions is known as the CCIR, from the French-language initials for International Radio Consultative Committee. The Oslo conference was the eleventh fully attended assembly of the CCIR. A previous meeting of a portion of CCIR at Vienna set part of the agenda for Oslo, and the discussion of a single worldwide color-television system was scheduled. R-E: How many delegates to this color-television conference were there? Dr. Brown: There were nearly 800 delegates to the conference, but color television was only one of the subjects discussed. You see, CCIR consists of 14 study groups, which are concerned with all forms of radio communications, their standards and definitions, and so on. Study Group XI is concerned with television, and color was formally discussed at the meetings of this group. C. Hoyt Price, of the State Department, was head of the US delegation to the full CCIR conference. Arthur Hall, of Bell Laboratories was spokesman for the US in Study Group XI, to which I was a delegate representing industry. There were some 12 or 15 other delegates to SG XI from the US, by the way, including people from the FCC. Mr. Remley: I participated primarily in Study Group X, where we were concerned with things like television film standards, for example. However, I attended some meetings of Study Group XI, and my own group discussed color-television problems, but we took no official action. R-E: How was the question of a universal color-television standard brought up? Dr. Brown: First, let me say there's quite a difference between a standard and a system. A standard is a rule or definition, established by government or industry, which everyone uses. A good example is the US standard of 525 horizontal lines in a complete television frame or picture. A system, on the other hand, is a method or means of accomplishing some goal. NTSC and SECAM are two different color-television systems; both can be used with 525-line standards, as well as with other standards. At the beginning of the Oslo conference, Study Group XI Chairman Erik Esping, of Sweden, asked two questions of the delegates: "When do you expect to start color-television broadcasting in your country?" and "What system or systems do you prefer?" The chairman then asked for "expressions of opinions," not votes. These expressions showed that the various countries favored a total of 4 systems. [See Table I. -Editor] It was asked if there should be a single world-wide system, and if so, which one? Well, it was obvious that with such a large group - about half the 800 delegates to the entire conference - very little could be accomplished toward arriving at some sort of agreement. The group was just too large and unwieldy. The chairman recognized this, and adjourned the meeting for several days after suggesting discreetly that some "cloakroom bargaining" occur before another meeting. R-E: Could you explain where the various systems were developed and what differences exist between them? Mr. Remley: SECAM III is a French development, like its earlier and now-obsolete predecessors SECAM I and II. SECAM III seems inherently inferior to the other systems. It uses an FM sub carrier which is always present and causes interference in some pictures, depending on scene composition. The overall picture quality is often relatively poor. The system requires a complicated receiver, which would probably be more expensive to manufacture than receivers for the other systems. SECAM III's advantages are that it can be recorded easily by ordinary monochrome video tape machines and can be transmitted by limited-performance cable and microwave systems. SECAM IV is the French name for the same system the Russians call NIR. Both countries shared development of the system, and have agreed to share credit. SECAM IV has never been field-tested. It looks good on paper, and should be easily handled by video tape, cable and microwave. We don't know for certain what receiver requirements are. Dr. Brown: A great deal has been said of the ability of PAL and SECAM to overcome differential phase errors. It was fully proven in 1965 that SECAM worked a benefit in the presence of differential phase, and SECAM did not suffer too much from circuit noise. But, in the presence of both noise and differential phase, SECAM failed miserably. Furthermore, NTSC has been transmitted over a thousand miles on the Russian microwave system, from Moscow to many cities in Western Europe, and from Rome to London. The NTSC signal suffered very little degradation in these test transmissions. The French attempted the same feat with SECAM and didn't make it. PAL is a West German development, and at least it works, which is more than you can say for SECAM. Its primary advantage is its transmission quality, which is excellent. It can be handled well by limited-performance cable and microwave facilities, as well as video recorders. The Germans want to use full PAL all the way from the camera to the receiver, which isn't necessary. Besides, using full PAL makes the receiver more costly than it needs to be, and is PAL's major defect. We estimate that a PAL receiver, produced in the US, would cost the consumer $40 to $50 more than an NTSC model. The Germans claim that PAL alleviates ghosting and multipath distortion - which it does. But they make a big thing out of this feature, while we in the US know that, with few exceptions, a good antenna takes care of ghosting. PAL wasn't developed to avoid multipath - it was developed to overcome transmission problems. R-E: What transmission problems?
Table II - World Television Standards Mr. Remley: Most European cable and microwave transmission facilities have been built without enough phase and amplitude linearity to handle NTSC color. To use NTSC in Europe would mean either rebuilding many intercity transmission channels or not using networks. It's too bad this is so, for I think that unofficially many delegates felt NTSC was the best system, technically. Unfortunately, although simple to manufacture, simple PAL receivers have at least one serious defect - line crawl. Full PAL avoids this defect. The latest version of full PAL, by the way, while supposedly good on video tape, raises new problems. PAL gates the fields 1-2-3-4, unlike NTSC, and keeping track of the fields could be a problem, and might entail a more complicated tape machine. R-E: Was ART proposed? Mr. Remley: ART, for Additional Reference Transmission, is really NTSC with additions. [ART may also be used with PAL. -Editor] Its development is still incomplete, as work was done and papers filed almost simultaneously by both British and West German researchers. While never considered formally at either Vienna or Oslo, it was unofficially proposed by some as a simpler, cheaper alternate to PAL. R-E: Was NTSC proposed, and did it have any chance at Oslo? Dr. Brown: Yes, the US position favored NTSC. We have used it here since 1953: Japan uses it, and Canada started using it last September. There are at least ten million NTSC receivers in use in the US alone, to say nothing of Japan and Canada. Compare this with possibly a few hundred experimental PAL and SECAM receivers. We've had time to work the bugs out of NTSC, and I don't think anyone contests the fact that it looks very good today. American industry has spent a lot of money developing NTSC color, and the American people have a lot of money invested in it. It would be foolish to scrap all that - which is why the US won't change our system. The British agreed with us until we got to Oslo. No, I'm afraid NTSC didn't have much of a chance at Oslo. R-E: Why not? Dr. Brown: Well, at one point, the chairman of Study Group XI asked: "Are you in favor of a single system of color? If so, are you authorized by your government to change your vote?" The Germans answered that they could change their vote, but only after returning to West Germany and consulting with 5 or 10 agencies and committees, which would take nearly a year. The British said substantially the same thing. The French said they had the freedom to vote for either SECAM III or SECAM TV. The Belgians were very confusing in their answer. R-E: In other words, in spite of NTSC's obvious technical advantages, except for European cable and microwave problems, the delegates would not favor NTSC, nor any other single system. Why do you suppose this happened? Dr. Brown: Each country's decision to favor a certain color system was political, not technical. For instance, PAL is supported by West Germany, Great Britain and several other European countries. It may become a European standard. But Russia will never adopt a German system, because of the deep anti-German feeling that still exists from World War II. Similarly, France refuses to consider PAL because of the pride they feel in their SECAM. R-E: Were engineering features of the various systems considered at all? Mr. Remley: Engineering features were the ostensible reasons for favoring one system over another. As mentioned earlier, European transmission circuits make NTSC transmission more difficult there at present. And PAL is touted as a great cure for ghosting. But underlying the technical reasons were political motives. R-E: What about the possibility of a compromise? Dr. Brown: The French made a suggestion to that effect, but it wasn't much of a compromise. They proposed that all member countries stop their present research on NTSC, PAL and any other systems, and pool their resources for one year to perfect SECAM IV. If at the end of one year, SECAM IV proved to be a good system, it would be adopted as the worldwide system. If SECAM IV didn't work out, we would then be forced, by the terms of the compromise, to adopt SECAM III as the system. France's proposal, I'm afraid, didn't get very far. R-E: Was any position taken by Study Group XI on a color system for the world, or for Europe? Dr. Brown: No. The only result was that, after a couple of weeks of the delegates' doing nothing, Chairman Esping appointed a small group to write a report. This report outlined the engineering features of the systems that had been proposed. No single system was recommended or adopted by Study Group XI. Mr. Remley: It was unfortunate, I think, that there was no agreement. I believe the various nations of the world are playing ostrich; many have too little concern about seeing what's going on outside their own countries - and I include the US in this statement. Think of what a tremendous advantage a single world-wide system and standard of both monochrome and color television would be! With satellite relays and possibly direct satellite-to-home telecasting, a single system and standard would permit instant communication between all nations. Such events as the Olympic Games, President Kennedy's or Winston Churchill's funeral, Queen Elizabeth's coronation, could be shown live to the entire world. A single pooled camera crew could handle the origination. At the present time, such an event requires a completely separate camera crew, with tons of equipment, for each system in use. Of course, you can use film, which is playable equally well on all systems, but you lose immediacy. Dr. Brown: It would be nice to have a single worldwide system, but I don't think it's possible - at least not through the UN. You've got to remember that most actions of the UN are basically unenforceable. Even if a decision is reached, it's subject to voluntary compliance by member nations. What do you do if several countries decide not to cooperate? R-E: Several monochrome systems are presently in use in the world [see Table II -Editor]. The British have used 405 lines for some time, and the French, 819 lines. Most of the rest of Europe uses 625 lines. Recently both Great Britain and France started supplementary 625-line services, while maintaining their other facilities. Do you think this heralds a single European monochrome standard? Dr. Brown: Well, there was general agreement of Study Group XI several years ago that when anyone went to color in Europe they'd do it with 625 lines. You must remember that 625 lines is the 50-field equivalent of the US 525 lines, which is of course on 60 fields. There are some differences between British, French and other European 625-line systems, but these could well be ironed out and we might see a single European standard. Mr. Remley: Speaking of 50-field standards, which are used in Europe because of 50-Hz power lines, the use of 50 fields and 25 frames causes noticeable flicker as compared with our system, which uses 60 fields and 30 frames. R-E: At present, what facilities exist to allow, say, British audiences to view a live US telecast? Mr. Remley: Standards converters are used. The US networks have them - at least in New York City - and the BBC and others have them in Europe. They are complicated, expensive, and may reduce definition. There are two types - electronic and optical. When the frame rates of the two systems are identical, it's possible to use an electronic converter, which gives the better picture. R-E: To summarize, then: The UN-sponsored Oslo CCIR conference did not result in a decision to adopt a single world system of color television. It did show, however, that the various countries grouped themselves around three systems-NTSC, PAL and SECAM. These groupings seem to be political, and the technical advantages and disadvantages of the three systems were not the main reasons for the groupings. * "Color Television Throughout the World," January 1965; "The Case for NTSC in Europe," March 1965; "Color Television Systems: Which Way Will Europe Go?" July 1966.
Posted March 22, 2023 Color and Monochrome (B&W) Television Articles
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It is kind of hard to believe that even by
1966, when the International Telecommunications Union (ITU) met in Oslo, Norway,
that the world had not yet agreed in a common transmission standard for color
television. In January of 1967, Radio−Electronics magazine editor Thomas Hasket
interviewed two major players in the industry, George Brown of Radio
Corporation of America (RCA), and Frederick M. Remley, Jr. of Society of Motion
Picture and Television Engineers (SMPTE), regarding the stalemate that was
unarguably hampering the ramping up of color television set production.
Consumers were pining for them, but companies hesitated to invest engineering
and manufacturing resources when they couldn't be sure it would not be thwarted
by a change in the modulation scheme. A battle was being waged between the U.S.
