Karsten Rentz
Media Succession, From Film to digital Video, Progress – Problems – Prospects

Media succession was always both limited and driven by this TRIANGLE:

• Aspect of technology
  
• Aspect of economy
  
• Aspect of art
  

For someone who studied the histories of media it is amazing, that these aspects can not be separated and that any of this aspects gave always a feedback to the others as well it was also influenced by them.

This lecture will show the historical interactions in film and television/video production, than explain the today film and video standards (especially HD and the difficulties of compatibility with SD and feature film) and come back to this triangle at the end, in order to give some hints for a discussion.

• Film (Silent Movie, Sound Film, Color Film, Cinemascope, Surround)
  
• Video (Television, analog Video, digital Video, DVD and beyond)
  
• Digitalization (Punch Card Machine, Valve, Zuse/Eniac, Transistor/IC, PC)
  

The foundation stone of our multi media world today was laid at the end of the 19th century. Sound, (moving) pictures and digitalization started partly as scientific items, toys or fun fair attraction. There could be named a lot of people, who were involved in the development of records, films and digitalization, but I would like to name three of them in substitution for all others:

• Emil Berliner, who invented the Gramophone
  
• Auguste and Louis Lumière, the inventors of the cinema
  
• Thomas Alva Edison, who invented a lot of things, which are still important for Audio, Film an Digitalization
  

It is interesting to see that the film only needed 15 years to change completely: the fun fairy attraction had become an element of art (or better: a complete new way of art expression). This also caused a change in the economy (from the former film handy man, who was producer, camera man, distributor and projectionist in one person, to the film industries, from a individual cinema to a cinema of genre and stars, from the nickelodeons to the film palace and from the short movies to the feature film). All this changes in art were at any time also partly a concession to the economy efforts of cinema.

It is also interesting to see, that the "logical technical progress" of film was delayed at least in two points due to the fact, that there weren't any economical needs: the invention of Sound Film and the invention of Color Film.

he sound film, technical available at 1921, needed almost ten years to become a new film standard. The reason for this was, that there were no needs for the artists to use sound film. The opposite was fact: In Europe, what was more the region of Film Art, film maker refused the sound film as a "non-artistic" medium and in the USA the sound film was refused for a long time because it limited the distribution to one language, what wasn't desired in the "melting pot".

The most popular examples of sound film refusing is the transformation triple of Charlie Chaplin's "City Lights", "Modern Times" and "The Great Dictator". In "City Lights" he uses sound film only to give the silent film a fixed music, in "Modern Times" he uses sounds and noises, but spoken words can not be identified easily (what isn't also necessary) and in "The Great Dictator" the spoken words are only ironical paraphrases until in the end Chaplin uses spoken words to give his heart message to the world.

But the launching of sound film (what was ironically once again a strategic economic decision of the Warner Company in 1927) triggered the invention of some important new genres: the music film (revue, musical) and the screw ball comedy and from this point on there was now way back to the silent movie.

But after the WW II, what also marked the end of the European "Film Art", there was a new serious enemy of the cinema: the broadcast television. To fight against this new economic challenge, cinema had two strategies: to be better than TV (for example in a technical way) or to be cheaper.

To become more attractive the cinema now changed into "Color Cinema" (the technical possibilities for this were invented at the end of the 20ies but hadn't an economical brake through for the majority of the films). But this advantage only lasted a few years due to the fact that NTSC (the US Color TV Standard) was invented in 1953. The other new attraction was the invention of wide screen films, what also had an influence to the film content (for example Western).

The strategy to become cheaper had its effect on the growing number of B-movies. This also influenced the content by bringing up new genres like Sci-Fi- or monster-movies, but also created a film pearl like "Psycho" (Hitchcock was also one of the first film maker, who tried to use both, film and TV, with its own advantages for the distribution - an early type of cross platform distribution).

This coexistence of TV and cinema lasted 20 years when a new invention threatened both: the possibility to store and display video at home, the VCR. But this threat was turned into an advantage, since the film industry learned to use this new distribution channel at latest with the triumph of the DVD. There are still threats today for the film industry, especially digital piracy, but we will have to discus in the end what predominates: the benefits or the detriments of the technical progression.

Film Speed
The Cinema Film is projected with a film projector. To give the illusion of movement, filmmaker early found out that a picture frequency of 24 frames per second was needed (what is still the film speed today). To avoid the stroboscope effect, every frame is shown twice with a short "black" interruption. It is amazing that the audiences in a cinema sit nearly half of the time in complete darkness and does not recognize it!

Aspect Ratio
The "aspect ratio" (the proportion of the height and the width of the picture) was a long time discussion point for filmmakers and a wide field of experiments. There are today some standardizations but if a filmmaker wants to experiment with the aspect ratio, film still gives him all the opportunities. The most common aspect ratios in film are:
1,33:1 (4:3; Academy)
1,66:1 (European Wide Screen; also 1,75:1)
1,78:1 (16:9; aka 1,77)
1,85:1 (American Wide Screen)
2,2.1 (70mm)
2,35:1 (Cinemascope anamorphic)
It is important to know that the aspect ratio needn't to be established completely during the filming process since the resolution of film footage is good enough for later changes. The production frame for example may display the microphone boom, which is cropped during the process of final copying.

Hue
Since there are (or have been) different color systems in the film industry (Kodak Color, Agfa Color, Technicolor etc.) the hue of feature films can be very different. To get a color picture in the cinema, a process of additional color mixing is used. Normally three key colors (red, green, blue) of the color circle are used to display all other colors between this. The color systems have the most differences in the selection of this key colors.

Resolution
The resolution of film footage depends on the film format (16mm, 35mm, 70mm) and the chemical quality. The most important difference to a video or digital resolution is that the picture error of the grain (if zoomed very much) has not a pattern or scheme. So the picture noise has an irregular character and isn't visible too easily. The contrast of film has a range of 200:1 and the graduation curve isn't linear, but this fits more to the way of human perception.

Sound Format
Cinema is mono (with additional speakers). Due to the fact that a person who sits at the right side of the cinema will always hear the right speaker first (and loudest), he will have problems to match the sound to the picture. So any of the stereo experiments in the cinema came to the conclusion, that a center speaker was still needed and even more is still the most important speaker. To get an ambience feeling, a LCR (left, center, right) configuration was established in the late 70ies and completed as the now world standard of Dolby SR (Dolby Spectral Recording, aka Dolby Stereo; aka Dolby Surround or Dolby Pro Logic in the consumer market) with a additional surround channel (LCRS). This standard was transformed and enhanced when Dolby invented Dolby Digital with a 5.1-configuration (Left, Center, Right, Left Surround, Right Surround, Low Frequency Enhancement).

Frame Rate NTSC / PAL
The frame rate of the two most important TV standards was founded by the frequency of the network voltage: 60Hz in North America and 50Hz in Europe. These frequencies were halved so that the NTSC standard worked with 30 frames per second and the PAL standard with 25 frames per second. (In order to get the bandwidth for color TV, NTSC was actually lowered to 29,97 fps).

To display a picture on a TV screen, it is divided in thin horizontal lines, 525 (485 visual) for NTSC and 625 (575 visual) in PAL.

To avoid a stroboscope effect, one frame is displayed in two fields, the first field displaying all odd lines and the second all even. This procedure is called "interlaced" since the two half pictures are striped together. If all lines are displayed or recorded one by one this is called "progressive scan". "Interlaced" is normally used for the standard broadcast application while "progressive" is used in HD or in the process of film to video transferring.

Aspect Ratio
The aspect ratio of analogue TV was established with 4:3. But in the last 10 years also 16:9 became another standard. To match this with the old transmitting system, the picture was simply stretched horizontal (also called "anamorphic" similar to the anamorphic cinema method).

Hue
The analogue TV has only one specification of the hue in RGB: 700nm, 546nm, 436nm (wavelength of the light radiation).The range of the composited colors is also limited by the transmitting procedure. The result is that there are "illegal colors" on TV. Theses are colors, which may be generated with a computer or in an early stage of production, but can't be transmitted correctly in PAL or NTSC.

Sound Format
The sound format of TV started as a mono sound. But starting in the 80ies more and more the stereo sound (or two channel sound) was established. In opposite to the cinema this worked pretty well in the small dimensions of a living room, since the loudspeaker were always positioned directly near the screen.

Resolution
The resolution of analogue TV depends on the bandwidth with which the signal is transmitted. The horizontal resolution is fixed by the standard but the vertical resolution can differ. Typical rates are 240 (vertical) lines (3 MHz) for VHS and 400 lines for an analogue transmitting (5MHz) while one line is comparable to two pixels. In a digital environment this was standardized to 720*480 (NTSC) and 720*576 (PAL).

Although HD TV started analogue, today only the digital standard is from any importance.

Frame Rate
Because Europe had a well working PAL system, the HD standards with the NTSC roots were the only one, which are established today. The frame rate is standardized as 60i (60Hz with interleaved frames what results in 30 full frames per second), 30p and 24p (progressive scan, what means similar to a cinema frame, that all lines, odd and even, are scanned and/or displayed at once). For a lower resolution also 60p is supported.

Aspect Ratio
The aspect ratio is standardized with 16:9 (only the lower resolutions can also work with 4:3).

Hue
The hue is similar to the TV analogue standard but has fewer limitations during the transmitting process.

Sound Format
In the production line more than two channels are supported. Stereo is already standardized but other data reduced formats (dolby, dts) may become a new transmitting standard soon.

Resolution
The best resolution of HD TV is fixed with 1920*1080 in its highest resolution. But also 1280*720, 704*480 and 640*480 are supported too. The highest resolution is equally good to a 35mm cinema display.

Frame Rate
One of the biggest problems of transferring film to video is the frame rate. To get a 24fps to the 25fps PAL standard, the film will be simply speeded up (running now 4% faster). The sound can be pitched up with the same factor or time compressed in order to keep the tune.To get film to the 30fps NTSC a complicate process (3:2 pull down) is needed. This process generates the video pictures by displaying the first film frame in the first video frame (in both fields), the second video frame with the mixture of the first and the second film frame (first field with film frame one, second field with the film frame two), the third video frame with a mixture of the second and the third film frame and the fourth video frame with the use of film frame three for both fields. While the PAL transfer is now in a kind of full frame mode, the NTSC mixes up whole and spliced frames!

The other way round is even worse: there now have to be displayed 30 different frames (60 different fields!) into 24 film frames.

HD does not have these transferring problems since it allows using the 24p mode. But if it is intended to go from 24p to standard NTSC (or the other way round), the whole problem starts up again.

Aspect Ratio
Since the (cinema) filmmaker is rather free in his decision what aspect ratio he is going to use, it is a big problem to transfer a feature film to video. If the feature film isn't produced in one of the two common TV proportions, the operator or director has to decide what to do: to crop or to use a letterbox format. Both procedures aren't really satisfying, since cropping may cut away important picture content and LB is wasting a lot of resolution (and will produce ugly black stripes on the display).

Hue
The hue of film and video is simply different, since the key colors are different ones. Far more the contrast ratio is much more limited in a normal SD TV application. So transferring will need an excellent educated operator and /or the director of the original feature film in order to get it similar to the original look of the feature film.

Sound Format
Transferring the sound from film to video causes three problems: A normal home video environment is still stereo. So a 5.1 sound has to be mixed down to two channels. The dynamic range of an SD TV transmitter is limited to a range of 45dB. So the dynamic range has to be compressed for TV. If data reducing formats are used (dolby digital, dts), digital artifacts can appear.

Today we are at a point, where the digital video starts taking more and more the place of the film. The benefits seem to be obvious:

Production
An HD produced film can be displayed directly after the shot.
The material is cheaper.
The equipment is or will be much more smaller than cinema equipment.

Postproduction
No more longer a film has to be transferred into video, in order to do an off line editing.
SFX can be made in the same environment, in which it will be displayed later on.
All chemical copying process isn't needed.

Distribution
No expensive theatre copies are needed.
The film may even be distributed electronically (no shipping costs).
DRM allows new ways of charging.

Archiving
The digital material will not change the look during the years.
The material, which has to be stored, is much more smaller.
Copying the material for safety is much more easier and cheaper.

But a few points may appear in the future to become problems or even more to change our understanding of film:

Archiving
We cannot be sure, that today stored data can still be read in a few years.
To get an impression of film, you can simply look at one frame against any light without any aid.
Storage errors of normal film are obvious – digital errors are not, but culminate into a fatal error.

Distribution
Every DRM may be hacked.

Production / Postproduction
Since the postproduction becomes cheaper it will influence the content and way of producing a film.

History has shown that the technical progression in the media will always have an influence on our social, economical and culture life. We can now see our media world changing – positive and negative.

Cinema was the worldwide culture mean of the 20ies century that predominated for more than 100 years and influenced our whole life. The digitalization now changes our (media) life once more in a radical way. It is not only a new technical way of filming what will seamlessly take place of the old feature film (and isn't at least compatible to film).

Producing and distributing (HD) video will become more and more popular, word-for-word. This will bring up new achievements but may also destroy old ones - or it may simply change our understanding of the media culture.

Literatur:

• Film Art: An Introduction; David Bordwell, Kristin Thompson; McGraw-Hill Companies 1997
  
• Professionelle Videotechnik; Ulrich Schmidt; Springer-Verlag, Berlin Heidelberg 2000
  
• DVDs produzieren und gestalten; Uli Plank, Thomas Köke; Galileo Press GmbH, Bonn 2002
  
• Film verstehen; James Monaco; Rowohlt Taschenbuch Verlag GmbH, Reinbeck bei Hamburg 2000
  
• Handbuch der professionellen Videorecorder; Jürgen Burghardt; Edition Filmwerkstatt, Essen 1994
  
• 50 Jahre deutscher Tonfilm; Hans Borgelt; Berliner Forum 8 / 79Die Entwicklung der Medien. Vom Film zum digitalen Video, Fortschritt – Probleme – Aussicht