Since the mid 90’s, networks have projected virtual graphics onto the field during sporting events for at-home viewers; the most successful example is the 1st and Ten yellow line system used in football. By providing the audience with important information without distracting from the game, the system has changed how we watch football. Despite its simple appearance, the line was actually a quite complex engineering challenge and revolutionized the home viewing experience. Due to the success of the yellow line, virtual graphics are now commonplace in all sports.
Nothing compares to sitting in the stands at a football game. The sight, the sounds, the surreal fan experience ― there is truly no better way to watch. But what happens when you are not able to attend in person? The next best thing is clicking on the television.
Home-viewing provides an entirely new and unique experience. The viewer is in the hands of the network: constrained to watch through the perspective of a camera and subjected to interruptions such as commercials. However, despite some of the shortcomings of watching through a screen, there are some benefits offered by television that are not available to the game’s attendees. Virtual sports graphics, from the subtle score box in the corner of the screen to graphics superimposed on the playing field, enhance the viewing experience and provide the audience with information to better understand gameplay and make events more enjoyable.
No graphic has had a bigger impact on sports than the “1st and Ten” system used in football. Simply put, the system “paints” a yellow line on the field marking the distance remaining to achieve a first down. Despite the seemingly mundane information that it provides, the technology required to create such an image is complex, and its impact on football and other sports is profound .
A Brief History of Virtual Sports Graphics:
Virtual graphics displayed on television have come a long way in a short period of time and, despite the recognition received by the 1st and Ten system, it was not the first graphic to appear in sports. During the 1994 World Cup, advertisers wanted to run their commercials during games; however, because soccer has no natural breaks, there was no way to do this without interrupting matches. To appease sponsors, ABC and ESPN created a constant element on the screen that also functions as a running ad: a box in the upper left-hand corner, which features a sponsor on top and the score and time below . While this technology solved the problem, it became evident that the score box had much more value than to the World Cup alone.
Three months later the creator of the score box, Gerard J. Hall, and the Fox Network brought the score box to the NFL; it first appeared in a preseason game relabeled as the “Fox Box” . By 1995, versions of the score box had spread to many other sports, such as baseball, basketball, and hockey, with both regional and national networks creating their own versions (such as the version pictured in Figure 1) . The box reinvented the home-viewing experience and created a market for other graphics that could enhance the viewing experience .
The potential for virtual graphics in sports was soon recognized by many pioneers of the field, and companies were formed, such as the graphics giants SportVision and SportsMEDIA Technology (led by Gerard J. Hall), with the aspiration to redesign the viewer experience. These two firms are responsible for essentially all of the graphics that are now commonplace in modern sports, including the revolutionary 1st and Ten system .
The 1st and Ten System:
Watching football prior to 1998 could get confusing. Without on-screen graphics it was difficult to follow gameplay, and fans watching from a television had to keep track of the physical first down marker on the field or listen to commentary from the announcers to understand the situation . Luckily, a group of engineers at Sportvision recognized this problem and attempted to create a solution. Their main objective was to design a system that could provide football fans with important information without detracting from the game .
The result was the “1st and Ten” graphics system: a system of cameras and algorithms that work together to generate a yellow line across the field marking the position of the first down. The line itself appears to be painted on the field along with other yard markers. When players and objects cross over the line, their bodies cover it up (as seen in figure 2). As the camera angle changes, the line maintains its position on the field. In fact, many viewers do not even recognize that the line is actually a graphic . The yellow line has become “as natural to the game as the green color on the field ,” and has won multiple Emmy Awards for technical achievement due to its success . When watching from the television, the line appears to be seamless and elegant; yet an astonishing amount of technology is required to make it work, adding to its magic .
How It Works:
Many steps must be taken prior to creating the seemingly unimpressive yellow line. Before each season, a 3D mathematical model of every football stadium is made. Each field has a different contour thus prohibiting a “one size fits all” model . Unique color palettes specific to the field and individuals on the field (like players and referees) also must be created. These palettes must take into account different playing conditions such as variances in the time of day and the weather. Finally, each camera is placed at a strategic position in the stadium and equipped with an encoder that monitors the angle, pan, zoom, and focus of the camera .
The system originally relied on three cameras: one on the 50-yard line and two others on opposite 20-yard lines . However, as camera-work and game-visualization has improved, the system has likewise evolved. During the game, data from the cameras and field measurements are fed into eight computers that run the system. Information from the cameras is sent to the computers approximately 30 times per second . Next, all of the data is fed into a central computer that creates the line .
The computer takes the 3D model and camera readings and determines which pixels on screen must be changed to create the yellow line we are familiar with. Differences between the field’s color palette and other objects on the field (such as referees, players, etc.) are removed from the calculation to make it appear as though the line is actually painted on the field and obstructed by the presence of these objects. Finally, the computer draws the 160ft line, updating it 60 times per second. With all of this data having to be taken into account, it is amazing that the average error of the line is less than 2 inches from the actual first down marker .
Over the years various improvements have been made to the system. Originally, a 48-foot truck filled with equipment was required to run the system, but the technology has been condensed to the size of a few tables that can be shipped to venues . Problems caused due to extreme weather have also been addressed. Heavy snow or rain can obstruct the camera’s view of the field and interfere with the positioning of the line. However, by taking advantage of a 2/3 second delay in broadcasting and by placing a human spotter on the field to accurately relay the down and distance the issue has essentially been fixed. Additional cameras can now display the line as well. The popular “end-zone camera” and “sky-cam” were originally presented challenges in projecting the line due their varying positions on the field. However, by using modified encoders that provide additional data on the cameras’ positions, they are now capable of creating the graphic . Despite all of these improvements, the yellow line has remained largely unchanged throughout the years and has proven to be an enduring feature of the sport.
Impact on Sports:
The 1st and Ten system has become an indispensable aspect of football and has acted as a stepping stone for the sports graphics industry. The yellow line costs $25,000 per game, yet even with the steep price networks are happy to cough up the money . “In fact, when Fox Sports tried to save money by cutting the line from its broadcasts 15 years ago there was an outcry from fans,” and just one month later Fox brought back the line . The 1st and Ten system proved that there is a viable market for graphics and that augmenting reality through a screen can actually add to the game .
Since the introduction of 1st and Ten, many additional sports graphics have been implemented, and the technology behind creating them is fascinating. For example, in baseball Sportvision is responsible for six different on-screen graphics that have changed the way the game is viewed, one of which being PitchF/X . PitchF/X uses three different tracking cameras placed strategically in MLB stadiums to triangulate the ball’s position and give you information about a pitch. From one pitch alone, the software can tell you the type of pitch, speed of the ball, direction it spins, and where it ends up in the strike zone. Incredibly, the software is accurate to within one inch . Like the yellow line, PitchF/X offers valuable information to the viewer without being an annoyance on screen.
The Distracting Side of Graphics:
Even with the success brought about by the implementation of many different graphics into sports, there are other visuals that have received backlash and have stirred up debate as to how much information is necessary for the viewer and at what point the visuals become excessive. Many fans want broadcasted events to appear as natural as possible and have called for limits when integrating the technology into sports.
“FoxTrax” is a prime example of an integrated on-screen graphic going too far. In hockey, a group of engineers assumed that viewers had a difficult time following the puck. The infamous FoxTrax, or “Glow Puck” as it came to be known, augmented reality and created a “computer-generated orange blob” in place of the traditional black puck . Using infrared emitters and shock sensors inside the puck, the system was able to track the disk on the ice and add graphics like tails to indicate the pucks speed (illustrated in Figure 5) . Many viewers actually enjoyed the glowing puck, but hockey purists, particularly Canadians, criticized the technology . FoxTrax’s constant movement was overwhelming, and critics argued it was a nuisance and showed a disregard for the sport . FoxTrax was eventually removed, but despite its failure, the technology sparked an important conversation regarding which information should be displayed.
The 1st and Ten virtual graphics system has not only revolutionized the home-viewing experience of football, but drastically changed the way all sports are watched through the television. Using technology to add graphics in sports is still relatively new, and visuals are continuously being designed and redesigned. Ideas such as “lighting up” the three-point line in basketball to reintroducing puck- and player-tracking technology to hockey are currently in the works, and the future of sports seems to be shifting towards these types of augmented perspectives .
As a snapback to the technology’s original intention, advertisements are the most interesting and controversial upcoming applications of game-time graphics. Advertisers already insert virtual ads into sports which appear as posters and banners inside the venue. They use these for the sole purpose of marketing a product rather than displaying information pertaining to the event. Despite being slightly annoying, as of now they are largely non-intrusive. However, this is about to change as the NFL, NHL, and NBA all have plans to expand virtual ad placement and will soon allow advertisers to place ads on the actual playing field. Sports leagues clearly want to maximize their profits, but this application risks driving away audiences and crosses a line where virtual graphics begin to detract from the viewing experience . The debate regarding the point when graphics becomes excessive will persist as new applications are introduced, but the technology is surely here to stay. To think, without the introduction of one simple yellow line in football, all of sports would be watched on the television differently
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