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Computer Graphics for Television

Computer Graphics for Television

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By Eric Sorbers, first used by creative artists to Rather than using analog circuits McMartin Industries create complex Lissajous figures, to create abstract designs-al- still and moving. Artist Ben Lapo- though Scanimate is capable of The skillful and creative use of sky, designed the first analog doing that-Computer saw the new graphics has system solely for artistic purposes in the device as a tool for adding added' an electrifying dimension to the . His creations, known as motion to otherwise lifeless corpo- programs and commercials. Visual Oscillons, are b&w and still rate and other static figures. capabilities that would have seemed . Mary Ellen Bute used an Although analog graphics systems beyond fiction in the 1950s oscilloscope and analog circuits in are capable of producing beautiful are available today at' prices even the early 1950s to make motion geometric designs and fantasy the smallest station or production pictures. And in the late 1950s, a imagery, they are also useful for house can afford. filmmaker, John Whitney used image manipulation of a more However, the phrase computer more sophisticated surplus conservative type. This author has graphics is a confusing one, for the analog gun to build an created film footage on a Scanimate pace of has resulted in 'image creation system using . opti- (using a kinescope recording cam- sucha variety of , cal/mechanical scanning. . era filming the high-resolution CRT devices, that now there are many But the did not display) depicting the moon circling forms of such graphics : some really find its way into TV graphics the earth and a rider on a horse posterize or animate still images; until the late 1960s when the moving across the screen. others turn graphic figures into Computer Image Corporation intro- Each of these scenes only re- moving abstract patterns; still oth- duced the Scanimate process, which quired a single litho original to be ers create pictures that look like has since been popular for advertis- created. In the moon , the or even like . ing graphics, station IDs, and used litho consisted of a of the Some operate in real time-images extensively by the TV show Sesame moon and a drawing of the earth. are put into motion at full speed Street. In the rider sequence, the litho before the operator's eyes-others require slow assembly of pictorial information for later playback. Some systems operate directly in NTSC standards, others re- quire a TV or film camera, or other kind of converter. The graphics computer The kind of computer most facilities have these days to handle logging and bookkeeping is a digital computer. It stores and manipulates discrete ; or pulses, known as , that are combined to form codes which represent letters of the alphabet or numbers. Some computer graphics systems for television, especially the newest ones, use this type of computer. But there is another kind of computer also used for graphics purposes, and it probably hasn't been heard of since the 1950s, at least a form in called a computer. Oscillon No. 507; It is the analog computer. Ben F. Laposky . Analog computer graphics were first used by creative artist's to create complex Lissajous figures . ( courtesy of Analog computer graphics were Ben Laposky)

June 1.980 Video Systems 11 Computer Graphics

original showed a horse and a rider (each separately located on the eel)'. The Scanimate computer posi- tioned, sized and moved the- images accordingly to create the scenes described . Though simple visual , conventional film anima- tion techniques would have required dozens of original litho images or cels to be drawn. The Computer Image Corpora- tion has even developed a special system just for cartoon-style anima- tion. With this system known as CESAR, one can create standard animated cartoons using far less original than required by stan- . Liphtfall, Eric Somers . Electronic abstraction created by the author using an . dard optical analog system put together at Creighton University . Brushstroke effect is The Computer Image Corpora- similar to electronic possible with some digital systems, except that tion is not the only company that with the digital system representation art is also possible . Colonizer used was has produced analog graphics com- made by Colorado Video. (Photograph courtesy of the author) puters. Several years ago Steve Rutt and Bill Etra designed and built several models of the Rutt/Etra oriented. The operator of an analog movement that is unbelievably video synthesizer. They were simi- system directly manipulates, in real fluid and graceful. And this motion lar to Scanimate in some ways, time, the controls of the image is created in real time, so the artist although slightly different in capa- system. And the hardware deter- can experiment with scenes and bilities and operational . mines the kind of image manipula- time sequences to match musical Graphics produced by this system tions that can be done. Each system passages or to fit the metre of other have been used in major feature has its own visual vocabulary. To, action. films and national TV spots. use analog graphics to its best 3. Abstraction its a major part of Probably the most famous artist- advantage, the creative artist should the analog vocabulary . Although designed analog graphics system is know the workings of the system to there are many uses for analog the Paik/Abe video synthesizer be used. There are several agency computer graphics as a simple and designed by Korean Artist Nam art directors who have gone to a low cost substitute for conventional June Paik (known as the father of computer graphics house with a eel animated in creating cartoon- video art) and Japanese Engineer preconceived notion of the images type animation, a major attraction Shuya Abe. The best-known instal- wanted, only to find that the analog of analog computer imagery has lation of a Paik/Abe system is at system being used could not pro- been the fantastic look of the final Boston's WGBH-TV, although a duce that image. It is important to product. Whether used to modify smaller Paik/Abe system also exists understand the system first, then an image from a camera, or to at the California Institute of the come up with a visual that generate a kaleidoscopic design, the and perhaps elsewhere. Al- is within the system's vocabulary. output of the analog system usually though used exclusively for fine Unlike most other art , looks futuristic and modern. And it arts, (not commercial art), the analog imagery is determined more seems to be a medium that appeals Paik/Abe system at WGBH. has by the than by the to a generation brought up on TV been used by a number of now- operator. Six operators of the same viewing. But it attracts the most prominent artists, some of whose computer are apt to produce images attention in self-conscious applica- tapes command good prices by more alike than they are different tions where the images look elec- collectors . And Boston viewers have (in style if not in content). To get tronic and bizarre. enthusiastically received the ab- beyond the look of the machine, stract visual accompaniments to the analog computer images must be A digital world Boston Symphony concerts created combined with a completely differ- In spite of the capabilities and on the Paik/Abe by Ron Hays. ent medium. beauty of graphics sequences gener- Although there are many kinds 2. Motion is the analog system's ated by analog computers, it is of analog graphics systems, they all best virtue. Although some artists becoming a digital world. This does have three characteristics have made use of still imagery not mean that the specialized related to their creative use that the produced by a graphics computer, capabilities of the analog computer TV producer or ad agency art the real success of systems such as must be discarded; hybrid systems director should keep in when the Scanimate . computer and the are being built that provide some of contemplating the use of analog Stephen Beck, Rutt/Etra and Paik/ the advantages of both analog and imagery: Abe synthesizers can be attributed digital equipment. 1 . Analog systems are hardware to their capability to produce Some new analog systems are

1 4 Video Systems June 1980 other LSI tlarge-scale integrated circuits) devices has drastically cut the cost of hardware, and graphics programs are being written that allow an artist with little technical training to create images, still or animated, on a TV screen. There are several amazing but true capabilities of computer images: e Digital computer graphics can be produced on a CRT that are virtually indistinguishable from TV camera images. That is, the com- puter can create real images of real-life things that have shadings of light and color, shadows and highlights caused by apparent light Dancer, Eric Somers. Example of N camera image Cblorized by an analog sources; etc. system . Gray scale levels are replaced by new and tones to produce *Digital computers can construct graphics art effect . Colorizer used was made by Colorado Video. (Photograph animated sequences that almost courtesy of the author) mimic Disney-style hand-drawn animation, yet unlike similar ani- mations produced with analog sys- designed to be controlled by a program from a keyboard terminal tems, there are no original cels to digital computer, so lengthy visual in conversation with the computer. be photographed by a camera. effects can be programmed and This allows the to feed in e Digital computers capable of pro- stored in the digital computer's or a command and immediately see ducing color graphics suitable for memory for at the ap- the results, a big improvement direct broadcast (without any re- pointed time. Also, a digital com- (from a graphics standpoint) over scanning from a CRT display) can puter can be used to create images punching hundreds of computer be purchased for less than $4000. that are further manipulated by an cards, then turning them into a analog " system. Finally, digital-to- central operator who runs them and Image production analog converters can be used, returns the printout. Although there are considerable which along with the appropriate Even as became hardware and differences software (programs), allow a digital popular and major exhibitions were between the various, digital graphics computer to emulate an analog being mounted by distinguished art computers, the principles of image computer. galleries the output of a digital production and manipulation are The popular image of digital computer was still not: seen much the same. computer graphics is that it is on television. This was due to the A certain portion of computer something brand new-something fact that the computers being used memory, a portion often called a on the leading edge of technology. were exceedingly expensive, and the frame buffer,. is mapped for display. Actually, computer graphics are graphics images had to be created That is, each location in memory nearly as old as the digital comput- by with extensive corresponds to one pixel in the final er itself. A ray tube display training. TV stations and produc- display. If one thinks of the final designed for graphics was used with tion houses did not have the video image as being made up of a the early computer at personnel or money. Some meth- series of dots drawn by the compu- MIT in 1950. And graphs, engi- ods of programming took weeks to ter, each dot is one pixel. neering and even works of program the frames .for a 30-second The device that changes the code art. have been created by computers TV spot. This was not an apprecia- in memory into a video display is using pen ', CRTs, even ble savings over hand-drawn cel called the display controller. It printers (a la the computer portrait animation, and the images were not samples the frame buffer 30 times printers so popular in shopping as good. Also, there was no pro- per second and creates a video centers). Although the largest use of vision to preview the animated image by using the code stored in graphics has been for scientific sequence in real time. Early digital each memory location to create a purposes, many have been required each pixel of the appropriate brightness written about computer art, and image to be drawn by the computer and (possibly) color. On simple there are even whole magazines slowly and recorded on film, a systems the information for each that deal with nothing else. single frame at a time. pixel is contained in a single digital Probably the greatest boon to Digital computer graphics seems . This means that in such 'a computer art occurred in the 1960s new because it has only been system each pixel can only have two when interactive computer systems during the past five years that such states, on or off (corresponding to came into widespread use. These imagery is possible at low cost. The the binary 1 or 0). No brightness or are systems that the 'operator can development of and color variations are possible.

June 1980 Video Systems 1 5 Computer Graphics In a more sophisticated system for each frame, then the computer image quality and memory space/ each pixel might be represented by must compute all or some of the execution time. eight bits or even by a 16-bit digital contents of the frame buffer 30 How does a digital code of the word. The 16-bit pixel could have times per second. Needless to say, picture get into the frame buffer? 2'6 possible states or 512 possible each takes a certain One way was simply to tell the combinations of brightness and amount of time (no matter how computer what you wanted to draw. color. small) and if a high resolution Digital computers only manipulate It is clear that the more bits used a single digital word (usually 8, 12, to represent each pixel, the greater 16, 32 or 64 bits in size) at a time the memory space requirement using a special code. This was an will be for the display buffer. If the Visual capabilities that extremely slow and tedious process, number of pixels used to create an would have seemed but in the earliest days of computer image is also high (in order to graphics was the only way to achieve better resolution) then the beyond in produce pictures. amount of memory consumed by the 1950's are available Programmers very soon, however, the display buffer can become very today began writing graphics languages large. It is obvious that the more (either incorporated into general complex and real looking the final purpose high-level computer lan- image, the larger the computer it guages or existing separately) so will take to produce that image. display is used, the computer that pictures could be drawn using And if an image is to move in simply won't be able to make the a more compact programming code. real time, then the element of changes fast enough. At the present Various kinds of hardware have computing time enters. Note that level of technology, therefore, ex- been developed that, when used the display controller samples the tremely detailed animation is not with the appropriate software, allow frame buffer 30 times per second (if done in real time with most digital easy and rapid specification. of the video is US standards). If computers. pictures in a , animation is desired in which With digital computer graphics without having to write elaborate certain images are to be changed there is always a trade-off between descriptions:

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Circle (10) on Reply Card 1 6 Video Systems June 1980 i The looks like a little writing board lined in squares. A or other pointer is used by the artist. When he places the stylus against the drawing tablet at a certain point and activates a small trigger, circuits in the tablet where the stylus is on the drawing tablet and the computer, draws a point on the screen. As the artist moves the stylus, a complete image is drawn on the screen. Provisions are made for the artist to specify the color and brightness of each line, provided the computer is capable of storing such information about each pixel in its memory. Since this form of entering picture information is so similar to ordinary drawing it is becoming popular with artists especially now that programs exist that allow the artist to use the computer without having studied programming. e The light pat is a stylus, that is placed directly on a screen in order -of-the-art analog . computer Images by Computer Image Corporation using to define . a location. It is usually Scanimate. (Photograph courtesy of Computer Image Corporation) less accurate than the drawing

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June 1980 Video Systems 1 7 Computer Graphics

tablet, but is often used as a pointer when selecting commands from a printed or when pointing to graphics figures you want the computer to manipulate (for example, enlarge, rotate, change color, etc.) The digitizer accepts images from a TV camera and translates the output into a digital image in the frame buffer. This is what is used by computer portrait systems and also what allows for digital special effects using ordinary TV images (as are possible with some of the newest production switchers). Painting, Fred Yung. Example of electronic painting created on the Ampex Computers can be programmed Video Art System (AVA) by Fred Yung . (Photograph courtesy of Ampex to manipulate the contents of . the Corporation) frame buffer memory (or any other memory location that may be used to store pictures waiting to be displayed, or control information, digital computer are so far removed real; time, and must be recorded. on etc.) These manipulations can result from the operations of an applica- film from an extremely high-resolu- in color changes, rotations of all or tions program that even a profes- tion display. Initial programming is portions of a picture, enlarged, sional using a high- quite costly and time-consuming, reduced, squeezed, expanded or level language doesn't need to know though making later changes in replicated images. much about the circuits he is using. movement of already defined im- Storage is the digital computer's He just needs to know the language ages can be relatively inexpensive. strongest virtue. If a digital com- and its features. Synthevision images are created puter can do nothing else, it can with a 3-D perspective, so even store a graphics image for future Real systems cartoon using 'the pro- reference. As a result, graphics There is not enough space to cess tend to look more like puppet information of a detailed nature discuss every digital graphics system animation than traditional cel car- can be displayed and images can be available, but included are a few toons. created that don't look especially that have contrasting features to get A process designed to simulate mathematical . Each image may an idea of the range of products the look of cartoon take some time to create, but the made. animation is VideoCel offered by storage feature allows the. computer In introducing digital graphics, a Computer Creations of Indiana. to recall the same image time and system capable of producing real- The process was developed by two time again for use in a different looking images, near photographic engineers, Thomas Kli- way. , in quality, and systems capable of mek and Richard Brown, who had Digital graphics require planning. Disney-style animation have been formerly been involved with com- Although some have analog controls discussed. puter graphics applications in the to provide some real-time- manipu- These systems are so complex missile industry. Their intent in lations, digital systems are best that the equipment is not sold to designing VideoCel was to create a used when the desired images are individual production houses, but computer, animation process in planned. and' put into a program rather computer experts who have which the artist has the most direct that the computer can execute on assembled the necessary hardware possible involvement. This is in demand. This differs from the and software offer use of their contrast to computer graphics free-form trial-and-error method facility and staff on a fee basis. houses that expect an agency to that can be used with an analog The most real-looking images, submit a storyboard for total execu- system. this author has ever seen produced tion by the computer firm. Digital systems are software ori- by a computer without camera Key drawings for the animation ented. If the analog graphics artist input are those created by the are drawn by the artist using a must be an expert on control Synthevision process developed by digitizing tablet. The computer circuits and waveforms to make MAGI (Mathematical Applications then calculates the movements in best use of his tool, the digital Group, Incorporated). The images between the drawings needed to graphics artist must understand the are created for a variety of applica- make the action complete (using operation of the program used to tions from advertising to architec- information put into the computer produce and manipulate digital tural modeling of new buildings by the operator) and creates the graphics. and military simulations. The ani' sequences. Animation of the 30-sec- The actual internal workings of a mated sequences are not created in ond TV spot takes about a week-

1 8 Video Systems June 1980 Computer Graphics much less than the standard five to six weeks for conventional anima- tion-but the cost is about the same as cel animation. Sequences can be recorded on videotape or, film. Like Synthevision, VideoCel uses a high-resolution display. Of perhaps' greater interest to most production houses and TV stations is equipment that can be owned in-house for daily use. Three systems (there are many more in existence), will be considered. Each is designed for a very different sort of graphics . The systems are the Ampex Video Art Systems, the Teleshator and the Apple Comput- er. Most readers -have proliably seen Albert; Soul Bemstein. Electronic painting done on an , Apple Computer . (Photo- the output of the Ampex Video Art graph courtesy of Apple Computer) system in the Superbowl XII com- puter drawings by artist Leroy Neiman. Indeed, the entire system In to the creation of every time it is to be put on the is designed solely to produce still hand-drawn images, the system can screen. The on the screen drawings of the highest quality accept graphics input from a TV can. be moved and/or change size in using techniques familiar to tradi- camera and digitizer. This allows rea-time. tional artists. The system dedicates basic artwork to be quickly digi- If the Ampex system is aimed -at an 8-bit word to each display pixel tized and then changed or embel- the needs of the experienced artist, giving the artist 256 color/bright- lished by manipulating the creative. the Telestrator is aimed at the ness combinations per drawing. functions of the computing system. needs of the non-artist. Symbols Each combination can be defined The system does not offer direct can be created off camera before by the artist from a virtually real-time animation, but drawings air time and then be made to write . limitless total number. can be created and stored on a themselves on, or even to erase The artist works at a drawing for playback in real time. themselves, to give the impression tablet with ' a stylus that can be The Telestrator by Interand most that the weatherperson (or sports- used as a brush. Different brush resembles the operational features caster, newsperson etc.) is drawing sizes and shapes can be selected of an analog system. It is a the symbols in real-time. Of course, from the menu-even new brush dedicated computer sys- the symbols can actually be drawn styles can be created--so that each tem designed to be used by in real-time, but the automatic stroke of the stylus can seem to be facilities with a minimum of effort. drawing feature , can help steady a stroke with a wide or thin If the Ampex Video Art system is possible on-camera jitters of the paintbrush. To save time, the artist designed to be an electronic canvas, non-professional artist. can command the computer to fill then the Telestrator is designed to Since the Telestrator is not any bounded area with a certain be an electronic answer to the -designed for fine arts applications, color. A font mode allows the artist weather reporter's magic marker or most of the features of the to add alpha-numeric information. the-sports analyst's chalk. Ampex system are missing. Howev- There is even a history mode that The system makes use of a er, the system- is lower priced than provides for the storage and retrie- special transparent tablet placed the Ampex one and is built into a val of every color choice and pen over a TV monitor. As the stylus is small lecture-type console. It is also motion used to create a drawing. moved over parts of the tablet, the heavily advertised to the education-, Also, portions of a -drawing can be system the values and deter- al broadcast market as a more changed in size or repositioned mines the stylus location. The convenient, flexible and sharper without the artist having to redraw system is capable of drawing con- answer to the . An the form. tinuous lines of various widths, and interesting sidelight is that Interand Every attempt has been made by dotted and dashed lines. There is has available a separate Memory/ Ampex to devise -a, system capable also capability for storing prese- Scan Converter package. This unit of producing paintings rivaling lected symbols for manipulation .in accepts analog input and can even those produced by conventional real-time by reference to the posi- be used as a storage oscilloscope. brush and ink means. The system is tion of the stylus on the tablet. By using the proper analog circuit, designed for interactive use by Thus, a weather forecaster can use one could create analog still video artists in broadcast , stations and a predefined series of symbols to art of the type described in the first production houses and avoids any indicate storms, highs, lows, etc., part of this article (art similar to of the traditional electronic _look. without having to draw each one the Oscillons of Ben Laposky) and

20 Video Systems June 1980 of color/brightness combinations is much lower. The software package that comes with the Apple graphics tablet does not give the aftist as much flexibility as does the Ampex system, yet quite striking posterized paintings. can be achieved as, for example, the picture of Albert Einstein created by Saul Bernstein. No facility or producer should expect the Apple to take the place of more sophisticated graphics sys- Teteatrator. A color'Tefestrator Is used tems, yet small stations and pro- to manipulate the various characteris- duction houses might find the tics of a for the number 5. Apple a useful tool for making (Photograph courtesy of Interand and titles. Some artists use Corporation) the Apple to create sketches that can be stored on disc for showing store and broadcast these forms to a client before executing the using the Interand Memory/Scan final art in more conventional Number'one. Its Converter instead of using a re-scan non-electronic media. All in all, the easy to say. A lot of camera photographing the analog Apple is probably the most flexible display. of the systems described in this people do. But One The final system is the Apple article. But the flexibility and low Computer, a purchase price are offset by creative Pass is the ONLY with quite a bit of graphics limitations that should not be taken complete film and capability. At the outset it must be lightly. pointed out that the video output of No article on digital graphics video facility in the Apple Computer as it comes would be complete without men- from the manufacturer is not NTSC tioning some of the special effects Northern California broadcastable color video. However, possible with digitally controlled that rivals the best a converter board designed to make video switchers. Some of these can the Apple graphics broadcastable store images and change their size, in L.A. That s a has been announced by Video relocate them; replicate them, etc. Associates Labs 'of Texas. This Sometimes their mouthful no one $1000 option is, a must for TV have been interfaced to analog broadcast applications. Since the controls so that the effects can be else can say. cost of the Apple is extremely low managed in real time with knobs in the first place (about $1200 to and levers, rather than with typed $6000 depending on options and commands. equipment) even adding Digital effects systems designed the Video Associates board still to in conjunction with - keeps 'the Apple graphics system ers include the MCI/Quantel DPE well below that of most competi- 5000, the Vital SqueeZoom and the tors. Grass Valley/NEC DVE systems. The Apple features both high- The zoom and rotation effects resolution graphics, and low-resolu- produced by these units could also tion graphics. The low-resolution be used effectively to animate still graphics can support 16 brightness/ images produced by the Ampex color combinations. The high-reso- Video Art system or an Apple lution graphics can support only computer. six color/brightness combinations Purists may argue that the new (black, white, violet, green, red and digital effects are mere "gim- blue) and not all colors are availa- micks," and certainly gimmickry ble to each pixel. has often been used in television to But of greatest interest to video replace artistry. But many serious professional. is the availability of a creative artists and producers are One Pass Inc. graphics tablet to give the Apple exploring digital and analog graph- 900 Third Street some of the features of the Ampex ics in order to seek new ways of San Francisco. California 94107 Video Art system. Of course, the communicating in pictures. In some 41 S / 777-5777 Apple is not as sophisticated as the cases the purpose is to realize cost Ampex system. The resolution is savings; in others, the intent is to lower (192 x 280 pixels in compari- make visual more son to Ampex's 562 x 512 or expressive. Sometimes it is possible optional 7,68 x 512) and the variety to realize both goals at once. Clrcle,(12) on Reply Card

June 1980 Video Systems 21

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