CGs yesterday, today and tomorrow

By Sergey Pchelovodov

Review contents:

CGs yesterday, today and tomorrow Software and hardware tools for TV programs graphic branding Graphic tools of DMS module system The use of XDR2-GENSEC in the systems of regional air branding Akula VTM video compositing system. New model range — new features Profitt’s titling and air branding systems, clock and logo generators Overview of the systems based on extended version of Alpha Pro software X-CG character generator — good choice for titles creation TitleBox graphic manager Clock Station Leitch’s equipment for air branding Matrox InfonetTV Deko CGs from Pinnacle Systems Company Pixel Power equipment Stream Labs.’s video cards Videoprinter system for DSC video switchers Videonics titling machines

Since cinematography was born the need arose to accompany screen actions with text notes. Recall silent black and white movie when fanny scenes with Charlie Chaplin were interrupted by black fields with white text. Such pictures can be concerned as first screen titling experience. Since that time titles were made manually for many years and then were captured by cinema and TV cameras. Modern television is impossible to be imagined without usage of titles, logos and branding graphics. Despite of wide range of computer graphics and visual effects presented on TV screen it is hard to overestimate an importance of a symbol on a screen. Looking at a symbol in a screen corner viewer is recognizing his favorite channel or decides whether he wants to watch particular program.

In TV production the devices for overlaying of text information onto image are called character generators (CGs). Up-to-date CGs is able to output not text but program brand shots, animated logos, visual effects, they can work within play-out automation systems and do many other things as well as titles itself can be 3D with shadows, backgrounds, edges etc.

Real boom in the development of titling has happened — similar to any other fields — with appearance and fast growth of computer technologies. In Russia many people remember ald good Amiga computer and simplicity and convenience of Scala application has become a fairy tail. To be honest it is necessary to note that software applications which serve for hardware part often are called CGs too, but for output information been generated a special hardware always needed. So to avoid be messed such software we’ll call titling software applications but saying character generators we mean hardware devices which allow solving titling task.

At the beginning of 1990s market of such products was divided onto PC-based CGs (computer CGs) and specialized devices designed as separate modules with closed architecture. Among specialized module CGs in Russia, thanks to support of Cyrillic fonts, wide popularity gained title machines from American Videonics Company (they tell that it was due to former Russian citizens working in the company). Even today in Russia title machine Videonics TM3000 with 51 fonts and memory for 16,000 symbols is popular. Classic example of computer CG was VGA AVer Pro card made by Taiwan ADDA Technologies Company (today AverMedia Technologies). It was made as ISA card with integrated 1 MB video adapter and is still in use in some small video facilities.

When computer CGs appeared the need of control software for them appeared too. Back in 1980s Image North Technologies Company (today Inscriber Technology Corporation) had made Inscriber software application dedicated to work with images and titles on a base of Number Nine video card. Users were impressed by wide range of opportunities which are becoming available with computer with this software. Real popularity in Russia Inscriber gained after 1992 when it was integrated into Matrox Studio editing system. Wide acceptance of Matrox products in Russia had been growing and DigiMix systems coupled with Inscriber CG Supreme package got wide acknowledgement. It had become rather which etalon most of regional studios can only dream of. Absence of affordable CG systems on the market pushed Russian manufacturers to develop their own systems keeping in mind Russian TV broadcasting nuances.

Alpha Pro package became popular titling application. Affordable price and support of cheap but well working hardware titling systems allowed Alpha Pro to share its sector among modern channel branding systems.

So user faced a dilemma: which of two device types choose? Which advantages have computer CGs and specialized module devices?

Specialized module CGs have two main advantages. First one is a easy to use and maintain. In fact such device needs to be connected and tuned once. Maintenance personnel can have no ideas about computers at all and is able only pushing appropriate buttons at right moment. Second advantage is reliability and protection against unauthorized access. Wide spread opinion that computers is less reliable because it can fail needs to be additionally explained.

First, it depends on what type of computer is used, who has assembled and configured it. If one think, than in any field there are devices which are more or less reliable and it depends first of all on manufacturer. Titling anyway is not most serious task among those ones computer may face. Don’t forget that exactly computers are providing reliable work of banking system for instance. So there is a conclusion: you will have such computer you have requested. The result depends on your approach to supplier choice plus quality if installation and computer protection. Yes, it is more difficult than just buy module device but it provides much wider opportunities. Computer may be infected by virus but is there need of permanent computer connection to Internet? I even don’t tell about computer games. Exactly the efforts of out-of-task usage of computer gave birth to myths of its non-reliability. Let computer do only task and you’ll get increase of its reliability. On the other side personal computer being more complex device is less protected against errors of unqualified user.

Second, specialized CG is also computer with downloaded special software application which can contain errors causing fail of a system. Processors installed in specialized CGs are less effective than modern chips of common use. It affects a speed of rendering and total performance of a device.

At the same time PC-based CGs usually less expensive, they are easy upgradeable and modernized via software replacing which is mostly not possible for specialized CGs.

Upon many other parameters specialized module devices give in to computer CGs which always have higher font quality, and wider set of features, and much more reach possibilities in terms of art design and font choice. New functions comes constantly at software upgrade, integration with other equipment and system is possible plus data exchange, integration into play-out and channel branding automation systems, extendable accessories etc. Computer CGs often don’t look like computer cards and it is not amazing because being video devices they combine modern digital computer technologies with traditional analog solutions well known in video equipment field.

It is necessary to say that there alternative and totally software methods of title information overlaying within NLEs. As a rule these are plug-ins for well known NLE applications, such as Title Deko, Title Motion, Power CG. But having great convenience this approach has also serious weaknesses in comparison with computer CGs usage.

The first and main one is quality of result. The symbols especially in small-size text must be well readable. Any modern algorithm of compression used caused small-size symbols edges quality degradation and appearance of artifacts on the border of regions with different brightness. It results in the need to avoid usage of small-size symbols, thin lines and edges. In non-linear editing systems working uncompressed have pretty minor distortions of small details which are invisible at the first glance but these systems are still quite expensive. So the symbols quality provided by most cheap computer CG is higher than one provided by NLE system tens times expensive. At the first look it may seems amazing but it is not. In the reality there is nothing amazing in it because good CGs can pass a video signal through themselves with no digitization, no filtering and no characteristics change.

Second matter is convenience and time. With non-linear editing it is impossible to overlay titles onto video in real time because no one of popular NLE systems neither overlays graphics onto passing through video signal nor forms and outputs key signal for mixing in external mixer. Besides, if there is ready for use branding shot and it is necessary to make a change in text even small one than it will be necessary re-render whole project every time. Of course doing it with NLE system is inconvenient. But frankly, modern multistream systems allow to output titles overlaid onto existing clip without rendering. But high price of such systems and impossibility to overlay titles onto passing through video signal doesn’t allow solving the existing problem by means of these systems. And furthermore, if it is necessary to overlay titles or logo is the digitizing of a whole film the appropriate way?

Slightly away in the line of specialized CGs stay devices for channel logo output named logo generators. Let’s mark that any modern computer CG and some models of module CGs also allow overlying one or more logos simultaneously. Logo generators as separate devices are dubbing logo CGs’ functions, and besides for logo creation and downloading it into logo generation PC is needed which looks unnatural. It is easier to get computer CG and install it into the same computer.

For a long time computer-based and specialized module CGs were keeping parity on a market but fast development of computer technologies has changed a situation. Computer CGs gained new functions and impress by flexibility and productivity. Besides, many NEL systems obtained new titling features and specialized module devices itself are moving toward computers — interfaces for data exchange with PC have appeared. For example, for Videonics PowerScript Studio 4000 it is possible to download graphic images, store and edit fonts on a PC. In some cases specialized module CGs serve as just buffer for output of information prepared on PC earlier.

Perhaps for this momentum PC became cheapest component of up-to-date television facility and many other devices intended to be controlled via computer. So that often appears a possibility of using PC at different stages of video production.

Modern computer CGS are more than just devices for titles, branding shots and logos output. As a rule there is a possibility to purchase multifunctional device solving at the same time other tasks and sufficiently increasing efficiency of investment for new equipment.

Let’s look at the following example: facility is just under development and non-linear editing system doesn’t bought yet. A question about why standard means for titles overlay which are incorporated into non-linear editing systems often don’t satisfy professionals’ hopes was already discussed. So the only question leaves whether it is possible to combine hardware real time CG and NLE system within singe device? The answer is “Yes” and an example is Forward card which combines editing system based on M-JPEG algorithm and hardware CG. The advantages of these solutions are small form factor and use of just single computer.

Yet few years ago this way allowed saving sufficient money but aggressive policy of Pinnacle Systems Company on the Russian market drove to strong decrease of prices for NLE systems and made professional solutions affordable not only for any facility but even for home use. Besides, professional computer CGs pricing just $700 appeared on the market. So, buying such a CG and, for instance, Pinnacle DV500 it is possible to get all this for just $1300. It is necessary to note that keeping in mind streamlined price decrease for computers it is more convenient to incorporate CG and NLE system into separate computers and connect them to company’s local network. But in any case the Forward card remains pretty attractive purchase for the users of component analog equipment.

Another example of multi functional device is CG with real-time rear projection feature. Rear projection (chroma key) function integrated in a such device adds several hundreds US dollars to the price while separate rear projection device will cost not less than couple thousands USD. Let’s typical situation when having integrated rear projection feature is useful. Keep in mind that such approach can be used in any live translation with an anchor in the studio and decoration replacement during a program is needed. In a weather forecast we need to have an anchor place in front of meteorological map as a background and it is necessary to output titles with city names and temperature values, channel logo, animated symbols of clouds, sun etc, sponsor’s logo, clock and so on. Use of real hand made maps and decoration is labor consuming and looks pretty archaic Use behind an anchor of fashion big plasma panels which display maps produces too high expenses and technical inconveniences: glows on the screens from light sources, shadows from objects to be shot, impossibility of highly bright lighting usage. And again, to output an image to plasma panel one needs a computer. Most simple and logical way for solving this problem see the computer based keying of anchor’s background during video capturing and replacing of this background by computer decorations or in simple words by weather maps which were pre-painted for instance in Adobe Photoshop. Rear projection module in the CGs is dedicated exactly for this task accomplishment. Convenience of this approach is in possibility of whole process control from a single integrated environment. To do it one need to prepare a script which defined output sequence of text, map images, logo and other different graphic elements. Besides, using two-monitor mode an operator can apply quick edit to scripts with preview in the preview channel with no interruption of other scripts executing on the main (program) channel. Interface of such programs is similar to text processors interface and work is based on WYSIWYG (What You See Is What You Get) principle. Such a system will cost about $1200 for composite and S-Video signals, and near $1800 for component ones. As a rule, adding some extra money it is possible to buy a sensor for automated temperature measuring results output. To be honest I must note that the software of NLE systems allows to make a chroma keying of video signal been digitized but despite of high labor consumption of this job the quality of a result needs to be better due to artifacts which take place around anchor’s contour caused by compression algorithms imperfection. And this approach is impossible in real time so it is not applicable to live air.

Let’s look at pretty typical case when potential user doesn’t know clear which additional CGs functions he may need. When asking about tasks which must be solved quite often hear an answer: “I need pretty titles”. Getting deep into details one can find out that user needs that logos and clock as well as phone survey results be output “themselves” plus he wants insert advert clip prepared on NLE. Sometimes user doesn’t imagine that so wide range of different tasks can be accomplished by means of computer CG. It is absolutely clear that we are talking about complex multilayer compositions controlled by previously created script and separate pages of it are being modifying by software application directly at the moment of output of incoming information to keep it updated. For example, it may be phone calls registered by modem or temperature sensor measuring results.

So we’ve reach to that the “layer” definition exists and it is important not only for NLEs but for modern computer CG systems too. Let’s note that we are talking about layers in real-time. So it is necessary to find out what number of layer the system is able to process in real time. Often an answer “Many” heard. It is not totally correct. Really it is possible to create several layers as frames with text, semitransparent backgrounds, pictures and other graphic elements, but speed and smoothness of such script executing will be limited by the performance of a system and a computer itself. Of course it means virtual layers within one hardware stream. So it is important to find out what number of hardware layers (streams) a system supports. Classic simple CG supports two hardware layers: video signal and graphics layer inside of which several virtual layers may be formed. More sophisticated systems support three and more hardware layers. As an example, with a situation of three layers one of them is video layer placed in between of two graphics layers and each of three hardware layers may consist of several virtual ones. Which advantages it gives to a user for phone survey system realization, for instance? Phone calls results are reported to the audience by means of creating of different diagrams included into TV picture and these diagrams are being modified during a process. To realize this program it is necessary to have a studio with an anchor and decorations as well as CG with phone call processing system.

In a case of CG with two hardware layers one can see a picture of a studio with real decorations and over it at the bottom phone survey results, program or channel logo are displayed. In a case of CG with three layers everything may be different. First, there is no need in a real decoration, because pretty background computer-made images are enough. Blue room for capture of an anchor is used. Second, survey results diagrams can be displayed both in front or behind an anchor and dissolve effect of a diagram on a screen is possible including a dissolve though an anchor. Also possible is further move of a diagram in three axis (for example, at the beginning an information is displayed in front of an anchor than the diagrams with survey results moved over behind him and upon discussing of these results the diagrams re-moved in front of anchor again).

At the conclusion let’s try to give several advices about what one should pay attention to choosing and buying computer CG:

• Two-monitor mode which allows to edit one script while execute another one;
• Preview TV output for view of prepared material on a TV monitor;
• Hardware support of titles roll and crawl and effects executing which provides equal speed and smoothness of script executing on a computer of any power. In CGs without hardware support all commands are incorporated in the programmable logics chips and all loading of their executing is laid on the computer’s CPU;
• Overlaying of titles onto SECAM signal may be useful. It allows to save money because there is no need in additional transcoder. In this case one must check whether a device is equipped both SECAM input and output as well as compliance with GOST 7845-92 Russian state standard;
• Video signal format conversion function (SECAM, PAL, S-Video, YUV, RGB) if necessary;
• Number of hardware layers. Optimal number is not less than three;
• Additional functions such non-linear editing or chrome key. Most advanced models are able not only overlay titles but also create virtual decorations in front and behind an object to be shot;
• Software for titles creation in the bundle of CG, because the cost of such software bought separately sometime is about half of system itself cost and a work without such software is impossible;
• Keep in mind that CG can work under different OS but it is better and more reliable to use Windows2000;
• If you are going to install CG by yourself than it is recommended to previously learn about potential interoperability problems for different computer platforms. Good device must have no interoperability problems with motherboards and must work on most popular modern computer platforms. A desire of a system provider to assemble “good” computer for minor money or an offer to by a motherboard from certain manufacturer may mean that the device has serious interoperability problems;
• And at last don’t forget about price: CGs with equal function set may sufficiently differ in cost.

Main trends of CG systems development are seen to the author in combination of the devices of different types on the base of computer technologies. Specialized CGs are getting “smarter” and presume remote control and active information exchange with PC through external interfaces. Computer CGs are gaining new functions and peripheries and are deeper integrated with NLEs, playout automation systems and virtual studios. As an example, I’d like to draw one’s attention to fast developing Tele playout automation system which opens new possibilities of CGs. For the first time it is possible to use video clips of different formats (DV, MPEG-4, DivX, M-JPEG, D1) within single project to overlay them onto passing through video signal. Video servers assembled on a base of popular CG systems and Tele software application successfully solve a problem of automated insertion of regional advertisement into signal coming in from central station. But this is a matter for another article.