WO2001054345A1 - Security systems for motion picture, video, program, and datafile transmission, viewing, access control and usage control - Google Patents

Abstract

Means are provided for secure transmission of motion picture information, video programming information, and other video information, as well as still pictures. The invention makes it difficult to obtain an illicit copy of data by borrowing or stealing a print or the digital equivalent from a motion picture theater, or to make illicit copies from the same. A data transmission is encrypted and electronically delivered to the intended recipient. A decryption key is stored on a physical storage medium, delivered to the intended recipient, and used thereafter to decrypt the encrypted data transmission. In one embodiment, a motion picture is transmitted to a theater via a communication link each time it is shown, at the time it is shown, so that a copy never sits in the theater. The invention further prevents the production of illicit copies of copyrighted material captured by videotaping or filming a moving screen in a movie theather. Variations which are reproduced by image capturing devices are introduced into a moving image, which prevent the generation of a viewing-quality copy by such devices.

Description

SECURITY SYSTEMS FOR MOTION PICTURE, VIDEO, PROGRAM, AND DATAFILE TRANSMISSION, VIEWING, ACCESS CONTROL AND

USAGE CONTROL

An object of this invention is to provide means for secure transmission of motion picture

information, video programming information, and other video information, as well as still

pictures. A further object is to make it difficult to obtain an illicit copy by borrowing or stealing a print or the digital equivalent from a motion picture theater, or to make illicit

copies from same. A yet further object is to control the playback of a video or motion picture recording. In one set of implementations, a motion picture is downloaded or

transmitted by a communication link to a theater each time it is shown, at the time it is shown, so that a copy never sits in the theater; the transmission being secured by means described in this invention; e.g. by a CD-ROM or DVD disk that is popped into the playback machine or projector.

Note further that downloading the movie to the theater each time it is shown allows

multiple movie theaters to be operated remotely from a central location. Accordingly,

our invention is both a security measure and a cost reduction. Note further that

downloading the movie to the theater as it is shown allows us to insure that the only

information in the theater is the next few frames of the movie; the information comes in, is projected, then discarded.

A yet further object is to make it difficult to illicitly obtain a viewing-quality copy by videotaping or filming the movie screen in the theater.

A yet further object is to make it difficult to produce illicit copies of motion pictures

recorded on conventional motion picture media (i.e. film), either by stealing or copying a

print, or by filming the movie screen in a theater.

The above objects would eliminate the sale of illicit copies of new movies; for example,

Star Wars Episode I showed up on illicit videotapes in Hong Kong as soon as it was released.

A yet further object is to support pay-per-view cable TV services or premium channels or

to avoid illicit access to cable TV signals, e.g. by 'pirate' set-top converters fed by illicit

taps into the system. A yet further object in some but not all implementations is to

optionally use portable storage media (e.g. as described in our previous patent, U.S.

Patent 5,771,291 or our pending U.S. Patent Application Serial No. 09/270,874, the

disclosures of which are herein incorporated by reference) of lower storage capacity than

the motion picture or video transmission; e.g. a single CD-ROM for multiple motion

picture or video transmissions. A yet further object in other implementations is to use a

lower-bandwidth transmission to enable viewing of a motion picture or video recording.

We also contemplate use of these methods for secure transmission of audio recordings;

e.g. songs, motion picture soundtracks, etc, and for secure transmission of software and programs, e.g. for on-line sale of software or on-line per-use renting of software. A yet

further object is to make it difficult to obtain an illicit copy by borrowing or stealing a

recording or a copy of the program or to make illicit copies from same. A yet further

object is to control the playback of an audio recording or the use of a computer program; e.g. again for per-use rental.

We further contemplate the use of these methods for the secure transmission of any

datafile wherein even a modest loss or corruption of information renders the file

unusable. Yet further objects are making it difficult to obtain or make illicit copies of said file, and controlling the usage of said file.

In our previous patent or application, we also described means for encrypting video

transmissions. [Hereinafter, the term "video" will include motion pictures and television

programs as two types of video.] The methods described herein differ in a variety of

ways; one reason is that the objects of the invention are different. We do not need to

absolutely obscure all of the information in a video or movie transmission, in order to

render a movie unwatchable or annoying to watch and thereby destroy the entertainment

value. This allows us to use means that are less expensive and/or require lower-capacity

storage media and/or lower-bandwidth transmissions, and/or that are less processor-

intensive and/or require less expensive hardware.

Our novel techniques as applied to videos are as follows: One class of techniques is to divide the information content in the video into two parts,

one part ("part A") to be transmitted, and a second part ("part B") contained on one or

more portable storage media. For example, the luminance information or signal for a

motion picture or television program might be transmitted and the chrominance signal

contained on a portable storage medium in the possession of the theater operator or user.

An individual who intercepted the transmission would obtain only a black-and-white

copy of the movie, of little commercial value; an individual who copied the disk would

obtain only moving colors of uniform brightness, which would be of no commercial

value. Note that in neither case is the information totally obscured; for example, the

black and white copy would show the plot and action of the movie; only the entertainment value is lost with the color. Since the moviegoer is buying entertainment, protecting the entertainment value is sufficient.

Note further that even this most basic implementation is difficult to reverse; colorizing

old black and white movies is extremely expensive and time-consuming, and the results

do not look entirely real. For the purveyor of bootleg copies of a motion picture, the

result would be an expensive copy, that does not appear realistic, that is completed only

after the initial run of the motion picture, typically at a time when authorized videotapes are already being sold to the public.

Note further that the term "portable storage medium" (PSM) includes but is not limited to

CD-ROM disks, DVD-disks, memory cards, floppy disks, portable hard disk drives, magnetic recording tape, and other portable optical, magnetic, or electronic information

storage media. It also includes the portable electronic devices (PEDs) recited in our

previous patent or application.

Note further that in this and all other implementations either the portable storage medium

or the transmission or both may optionally be encrypted and/or scrambled, e.g. by any of

the techniques recited in our previous patent or application.

Note further that we may optionally use different (e.g., unique) encryption or scrambling

keys or means for different playback units (e.g. projectors) so that a given transmission or

portable storage medium can only be decoded by the playback unit to which it is being

sent. Note further that the encryption or scrambling may be applied to the transmission and/or the data stored on the portable storage medium; or it may be applied to the video

information before it is divided between the two. In the latter case, the video information

must be decoded or unscrambled after being recovered by recombining the information in

the transmission and portable storage medium.

Note further that the portable storage medium may optionally comprise one or more keys

for decrypting the transmission(s). It may optionally further comprise decryption

software and/or terminal software and/or authentication software or means, e.g., as recited

in our previous patent or application. If one of our portable electronic devices is used, it

may optionally further comprise decryption hardware and may perform part or all of the decryption function. Accordingly, the decryption function may be performed by the

playback unit ("projector") or the portable storage medium, or by another processor or

unit or computer, or it may be divided between any of these. Note further that the

portable electronic device may implement any of the authentication functions recited in our previous patent or application.

Note further that decryption keys for information contained in the portable storage

medium may optionally be included or stored in the transmission or in the projection unit

or playback unit or in a second portable storage medium. For example, every week or

month, an employee of the distributor could visit the theater and load the new keys into each projection unit.

Note further that the portable electronic devices of this patent may further comprise

programs and/or processing capability to combine the transmitted and stored information

to recover the video information (e.g. motion picture). It may optionally further

comprise storage media to store a transmission in anticipation of a later showing. In

addition, it may comprise timing means, e.g to allow access to the information to decode

a given transmission only when at the time of said transmission and/or only at the time of

the scheduled showing. Said timing means may also be used to enable the unit to

recover a given video only at the time when said video is to be transmitted and/or shown.

It may also be used to restrict the rate at which said information is outputted; e.g. the

information may be output only when the corresponding information is scheduled to be received via the transmission. The portable electronic device (e.g. "cartridge") may

further require authentication & authorization e.g. from the transmission. For example, it

can be programmed to look for, decode, and require periodic reauthentications embedded

in the transmission as the transmission comes in while the video (e.g. movie) is being

shown. In the absence of same, the portable electronic device programming can refuse to

output the information and/or perform any other of it's functions. The portable electronic

device (e.g. "cartridge") may optionally further comprise means to input and/or alter said

timing information; either at the central location (before being sent to the user and/or

theater), or from a transmission or a second portable storage medium or portable

electronic device; said means being enabled by authentication means e.g. as recited in our previous patent or application.

It is further necessary to synchronize the information transmitted with the information

contained in the portable storage medium or portable electronic device. For example, in

the example above, where the chrominance is stored in the PSM and the luminance

transmitted, the chrominance information for each frame must be applied to the

luminance information for the same frame. Similarly, the information must also be

synchronized with any decryption means. One way to achieve this synchronization is by

synchronizing at the start and matching bit-by-bit through the entire video. For digital

transmissions, one may optionally include a "start" signal, typically comprising a given

digital word or sequence. However, it is often desirable to provide periodic synchronization checks and means for

quickly recovering from a loss of synchronization. One such means is by convention;

e.g. by dividing the both information streams into blocks and/or superblocks, and

matching up block-by-block. For example, a block could be the digital information for

one video frame; with the information being matched up frame-by-frame. In effect, the

beginning-of-frame / end-of-frame bit sequences function as synchronizing means.

Another way is to provide periodic resynchronizing means. One such technique is to

include conventionalized synchronizing signals or timing signals, e.g. a digital bit or

word or sequence of words in both the stored and transmitted datastreams. Another

preferred technique is to apply a block number or identification sequence to each block or

superblock in both the stored and transmitted bit streams. For example, one may apply a frame number to each frame in both the stored and transmitted bit streams. Directly

analogous means can be used to synchronize either datastream with the corresponding

encryption means or the combined datastream with same.

The means described above can also be used for the implementations that follow.

We contemplate a variety of other techniques to divide the information content in the

video into two parts, one part or datastream ("part A") to be transmitted, and a second

part or datastream ("part B") contained on one or more portable storage media. For

example, one part or datastream may contain the data for some blocks within each frame,

while the second part contains the data for the rest of the blocks within each frame. Similarly, one part or datastream may contain the data for blocks of the picture or blocks

of pixels, with the second part containing the information of where these blocks are

placed in each frame. Alternatively or in addition, the second part may contain the

information as to how these blocks of pixels are oriented. Similarly, "part A" might

contain the high-order bits in the datastream, while "part B" contains the lower-order

bits. Or "part A" may contain some bits, while "part B" contains the others. Similarly,

"part A" might contain one set of spatial frequencies in the picture, while "part B"

contains the other; alternately, "part A" might contain one set of temporal frequencies,

while "part B" contains the other. A directly analogous technique can be used when the picture is compressed by a spatial and/or temporal wavelet transform or when any other

spatial or temporal transform is used; some of the transform information can be contained

in "part A", the rest in "part B". Similarly, we can swap information or blocks of pixels

between different frames or (equivalently) swap them in time, with the information on

what belongs where contained in "part A" or "part B". A yet further alternative is to vary

the chrominance or luminance or both for the frame or for portions the frame in a video

signal in "part A", and include a canceling or compensating signal or information in "part

B"; e.g. anyone who tapped the transmission would see or record a video with varying

colors or illuminations within the frame or with time or both. Other techniques for

dividing the data are also suitable.

In general, "part A" can be any bitstream or datafile computed from the original bitstream

or datafile, containing some of the information therein, with "part B" being another bitstream or datafile computed from the original and containing some of the information

therein; "part A" and "part B" together containing all of the information in the original bitstream or datafile.

Note further that the audio information can be similarly divided between a transmission

and a portable storage medium by directly analogous means.

Note further that the techniques for dividing the information can be combined with each

other. Note further that any information described as being in "part A" or "part B" can

instead be divided between "part A" and "part B". Note further that the division can be varied, with the information on how it is varied either being a standard, or derived from

date-and-time information or some other reproducible source, or embedded either in the

information contained in the transmission ("part A") or in the portable storage medium

("part B").

Note further that we may choose to have more of the information contained in the

portable storage medium, e.g. to minimize the bandwidth of the required transmission.

In a limiting case, even a telephone-bandwidth transmission is sufficient to contain

enough information that the absence of said information would render the video or

motion picture unwatchable.

Similarly, we may choose to have more of the information contained in the transmission, e.g. to minimize the storage capacity required of the portable storage medium. This is of

interest particularly for applications like cable TV (e.g. for pay-per-view), where a wide

bandwidth distribution network is already in place.

Note further that the contents of the portable storage medium ("part B") might optionally

be the same for all theaters or users, in which case the same transmission ("part A") is

sent to each user. Alternatively, in a preferred implementation, the contents of each

portable storage medium might optionally be unique to each user or theater or class

thereof, in which case each transmission is unique to each user or theater or class thereof. Similarly, the contents of the portable storage medium might be the same for each

intended showing or viewing, or different for different showings or viewings. In the

latter case, the information for each showing is preferably erased after that showing or during the course of said showing.

In addition, the two techniques may be combined, e.g. resulting in a portable storage

medium that is unique to the intended user or theater, and also has unique information for

each intended showing. In this case, someone who steals or copies a portable storage

medium intended for one theater or user gets no benefit from recording any of the vast

majority of "part B" transmissions sent to other theaters or users; in addition, recording a

transmission for one intended showing does not allow viewing of the information for any subsequent showings. Note further that, for economy, one may optionally have a large-capacity storage medium

that contains the bulk of the information, and which is the same for all users or theaters,

plus a smaller user-unique portable storage medium or portable electronic device, which,

in combination with a user-unique transmission allows the video to be played. Note

further that the information on either of said portable storage media may optionally be

copied into a local server or into the projection unit or the like... Note further that either

of said portable storage media may optionally be replaced by another transmission,

typically prior to the viewing of the video. Note further that said transmissions would

typically be encrypted; the decryption need not be in real-time if they are transmitted before the viewing.

Note further than any encryption information can be divided between one or more

portable storage media and/or transmissions; said transmissions may either be concurrent with or prior to the viewing of said video.

Note further that a sealed portable electronic device, as recited in our previous patent or

application, may apply a date-and-time-dependent function to the information therein; in

which case, the information in the transmission would be correspondingly changed with

the date, so that the combination thereof yields the recovered video. This allows one to

have different transmissions on different dates (so recovering one transmission will not

enable one to recover the video), without increasing the required storage capacity of the

portable electronic device. As an alternative to the date-and-time, any other predictably varying information or function may be used. Of course, in all of the techniques described herein, the information described as being

transmitted may alternatively be contained on the portable storage medium, and the

information described as being on the portable storage medium would instead be transmitted.

Note that in any of the implementations recited herein, wherever the use of one portable

storage medium is described, one may optionally use two or more; e.g. in the possession

of different people to insure that no single person can show the motion picture or video.

For example, every week or every month or when a new motion picture is released, an

employee of the distribution company could bring one portable storage medium to the

theater and insert or copy it into the playback machine [e.g. "projector"] to authorize or enable said playback machine to play back a given motion picture. A second portable

storage medium, e.g. in the possession of the theater owner or projectionist could be

required to further enable each showing. Similarly, whenever the use of one digital

transmission is recited, we may optionally use two or more, for similar reasons; said two

or more transmissions may be concurrent or sequential or both. For example, repeated

transmissions to the theater's location may be required during a given showing of a

motion picture.

Note further that in any of the implementations recited herein, wherever the use of a

transmission and a portable storage medium is described, one may alternatively use two

or more different portable storage media; one or more of same assuming the role of the

transmission and carrying the information that would otherwise be sent in the transmission.

Similarly, we may alternatively use two or more transmissions or datastreams. For

example, one transmission could be made at the beginning of the month or when a movie

is first released. In one class of implementations, a special decoding unit or authorizing

unit carried by an employee of the distributor or other authorized individual is plugged

into the projector or said individual enters a special code into the playback unit (e.g.

projector). This transmission contains the "part B" of the information. The "part A" can

then optionally be downloaded as the movie is shown or whenever desired. Note that —

as a commercial matter — the special decoding or authorizing unit or authorizing code

could be entered into the playback unit at more frequent intervals, e.g. daily; in such cases, one might have a few units or a single unit in the possession of the theater owner.

Note further, that the playback units may also optionally be connected to a local network

in the theater; this would allow a single authorization unit in a central location in the

theater. Note further that said authorization unit might alternatively be software residing on an ordinary computer.

Similarly, one of said two or more transmissions may optionally be a low-bandwidth

authorization signal, e.g. to enable the playback unit or decoding functions or combining

functions, while the other contains a portion of the information or decoding keys or the

like. In general, the information can be divided in any way between the portable storage

media and the transmissions. Note further that in any of the above, we can optionally substitute an algorithm, e.g. that

produces a datastream from a key or keys, in place of part or all of the information on the

portable storage medium, or, alternatively, in place of part or all of the information in the

transmission. Accordingly, one may optionally replace either the portable storage

medium or the transmission or both with said algorithm.

In one preferred implementation, said algorithm is implemented in a portable electronic

device, which may optionally include a portable storage medium. In a yet further

preferred implementation, said portable electronic device requires an authorization code

for each playback or set of playbacks; said authorization codes coming from a central server or facility and/or from a human operator or user. Note that one or more

authorization codes can also be used to input a playback schedule.

Note further that any processing or storage function or authentication function described

as residing in a portable storage medium can be implemented in the playback unit instead,

and vice-versa. Implementing them in the playback unit allows these techniques to be

used with a portable storage medium (e.g. a CD-ROM or DVD disk) with no processing

capacity. (Note that the software to do this may optionally be carried on the portable

storage medium. Note further that the software might alternatively reside in a special-

purpose unit or board inside or connected to the playback unit; alternatively, the software

might be distributed as software, to be loaded into the playback unit or into a computer

connected to same). Alternatively, it can be used to allow a cheaper portable electronic device. Note further that we contemplate systems wherein the information is simply downloaded

from the portable storage medium or portable electronic device into the projection unit or

into a processor or computer or local server connected to same. Said information may

optionally be downloaded before each showing or all-at-once, or in sub-blocks. Note

further that the playback unit or processor or computer or local server can optionally be

programmed to then erase the portable storage medium or portable electronic device after

the information is downloaded; note further that a portable electronic device can be

programmed to erase itself after the information is downloaded, or a portable storage

medium may comprise programming to do the same, said programming being executed

typically by the playback unit or processor or computer or local server. For implementations where the information is read out as the transmission is received (e.g.

while the movie is being shown), the information on the PED or PSM may optionally be erased as it is read out.

In a cartridge-centered system (wherein the portable electronic device is the cartridge), it

may be desirable to move functions to the cartridge; the benefit of doing so is that one

can have a sealed cartridge, e.g. with electronic means of detecting attempts to open same

and erase the data if this is done, rather than a sealed playback unit (e.g. projector).

Note further that any electronic processing or information storage described as being

implemented in a portable electronic device or cartridge or in the projection unit can

alternatively be implemented in an auxiliary processor which may optionally be external

to the projection unit, or in a local server, e.g. in the theater basement. For cable TV applications (e.g. premium channels, pay-per-view, or preventing unauthorized viewing

of any kind), such functions may optionally be implemented a set-top box, or in

electronics inside the user's television set, or in an auxiliary processor, or in the users'

computer, or in a box anywhere along the cable TV distribution network.

Note further that for cable TV applications, any portable storage medium might also

comprise TV program information or other information of interest to the viewer, and

might optionally be presented as a TV program guide, as well as an access key, or instead of as an access key.

So far, we have largely discussed techniques in which the information is divided into two parts. There are other ways of accomplishing the same end. One technique is to encrypt

enough of the information to render the video unwatchable. For example, we can

encrypt any of the information described above as being "part A" or any of the "part B"

information. The advantage is that only a small fraction of the information need be

encrypted in order to render the video unwatchable. If conventional encryption means

are used, these techniques save on processing speed, which means that either a more

secure algorithm may be used or a less expensive decryption processor of lower capacity

may be used; in addition, decryption may optionally take place in real time. If a one¬

time-pad is used, these techniques can be used to give a radical saving in the number of

keys used; e.g. a CD-ROM disk could enable many viewings of one movie; alternatively,

a low-bandwidth link, such as a telephone connection, could be used to enable a viewing of a movie.

Note further that the decryption information for any video encryption technique may be

divided into a "part A" and a "part B" as described above in the techniques for dividing the video information.

Note further that for conventional encryption means, the transmission required to enable a

viewing need only comprise a single key, or a few keys if desired. Note further that the

decryption means may optionally be implemented in a sealed portable electronic device. In that case, the portable electronic device may require an authorization message from a

network or server, e.g. using means recited in our previous patent or application.

Yet another technique is to scramble enough of the information to render the video

unwatchable, with the descrambling information contained in a portable storage medium

of modest capacity or transmitted via a relatively low-bandwidth link.

Yet another technique is to add enough noise to render the video unwatchable or to

embed or add a pattern on top of the picture. The information to cancel or remove the

noise or pattern can then be contained in a portable storage medium of modest capacity or

transmitted via a relatively low-bandwidth link.

Note further that the descrambling information or the information to cancel or remove the

noise or pattern may optionally be stored on the same storage medium as the rest of the video, but in encrypted form. In this case, the encryption key would be obtained

separately, e.g. via an authorizing transmission or from a portable storage medium, e.g. as described above for encryption means.

Note further that, as recited for the "part A" / "part B" technique described above,

transmissions can be substituted for storage media and vice versa, multiple transmissions

or storage media may be used instead of a single transmission or storage medium, the

information described as being contained on a portable storage medium may instead be

stored in a local server or auxiliary processor or in the projection unit itself, etc.

Note further that any of the above methods can be used for the secure transmission or

storage of any other datafile wherein even a modest withholding or loss or corruption of

information renders the data unusable. For example, an audio recording loses it's

entertainment value if the data is scrambled in time or frequency, or if data is scrambled

or mixed between sampling points, or if noise is added or an interfering signal is added,

or if even a small amount of information is withheld or encrypted. Any of the means

recited for recovering the analogously treated video signals can be used here as well.

Similarly, a computer program is rendered unusable by even a modest number of changes

or errors or a modest amount of scrambling; even a single well-chosen bug will do. Note

that the end user runs an "executable file" for the program on his or her machine; that file

can be treated like any other file, and can be rendered non usable by any of the techniques recited for video or audio datafiles, and restored by any of the techniques recited above

for video or audio datafiles.

In summary, our methods can be applied to any datafile that has to be entirely intact or

almost so in order to be usable; e.g. datafiles that are usable as a whole, but where the

component parts individually are of little or no utility to the end-user. Such datafiles

include videos, audio recordings, computer programs, and more. Note that those

particular files also have other properties in common. For example, they are difficult or

impossible to restore by automated means. For example, a human being can recognize when a movie looks like a movie, but a computer cannot; accordingly, a computer cannot

do an automated search of a keyspace because it cannot recognize when the movie is restored.

We also contemplate novel means to defeat attempts to make illicit copies by filming the

video off the screen or by running the projector or playback unit into a video camera or

movie camera. For most of the following, we assume a conventional video or TV

camera or movie camera with a constant frame rate and/or regular and periodic scan.

We further assume that the primary threat is video or TV cameras, as most illicit copies

are distributed and sold as VHS videotapes. However, the same techniques can defeat

attempts to make illicit motion picture film copies.

One technique is to use a different frame rate than conventional video or TV cameras. This which will produce a jittery and unusable copy, especially if the frame rate is only

slightly different. For example, a 5Hz-to-10Hz visual "beat note" is exquisitely

annoying to most people; accordingly, a frame rate that is 5-to-10Hz different than that of

conventional TV sets is one possibility. Another interesting range is 1 to 5 Hz; note that

any visually perceptible flicker or instability rate may be achieved; note also that the rate can be varied.

In addition, we can vary our frame rate to further confuse any attempts to videotape the movie.

In addition, we can scan each frame in a different order, or in reverse order or in a varying order. In addition to varying the scan order, we can vary the scan orientation; we can rotate the scan lines. For example, we can scan the picture in the vertical direction

instead of the horizontal direction, or we can scan in a diagonal direction. If the diagonal

scan is almost horizontal, any attempt to videotape the move will result in an annoying

Moire pattern; e.g. between the almost-horizontal scan lines on a motion picture screen

and the horizontal scan lines in a camcorder being used by a member of the audience to

produce an illicit copy. Again, this is invisible to the audience in the movie theater, but

highly visible to anyone viewing the illicit copy. Note that the scan angle can also be

varied with time, again preferably at a rate that will be as annoying as possible to viewers

of the illicit copy. In addition, we can use herringbone or not-in-a-straight-line scans,

again with the idea of creating annoying Moire patterns in any copy. Again, we can vary any of these scan techniques. Note further, many motion picture projection units use a varying-optical-transmission

picture unit illuminated by a conventional projection light source; essentially, one has an

optical system similar to that of a conventional motion picture projection, but the film

itself is replaced by a LCD or other transmission picture unit that replaces the movie film.

This has two advantages. First, by reproducing the optics of the movie projector, the

result on the screen looks more like that of a conventional movie projector, and the

movie-goers see what they are accustomed to seeing. Secondly, since a broad-area

illumination source is used (e.g. a conventional projector lamp or reasonable equivalent),

it is easier to get the optical brightness required to illuminate the large motion picture screen; getting such brightness out of a projection television tube is difficult at present.

This projection method allows us to use a variety of novel techniques in which the illumination source is varied, one purpose of which can be to create a projection that

looks normal to the moviegoer, but gives in an unusable and/or annoying result when filmed with a conventional video camera. If required, the video signal can be adjusted (i.e., pre-processed) to compensate for any otherwise visible effects of varying the

illumination source. Another purpose of varying the illumination source can be to

partially or wholly restore an altered (i.e., encoded) video signal.

For example, we can illuminate different parts of the frame at one or more different times

during the frame time; this is invisible to the viewer, but very visible indeed to a video

camera, especially if the illumination pattern or sequence varies with time (e.g. at a few

Hz as described above to produce the most annoying videotape copy possible). We can create this time varying illumination pattern by conventional optical techniques, e.g. by

mechanical techniques (e.g. fast galvanometers or scanning optics), electro-optical

techniques, or by using several strobe lights. Any residual effect visible to the viewer in

the theater can be compensated for by pre-processing and changing the video signal to the transmission projection unit.

Note that there are a variety of easily realized mechanical illumination scanning

techniques. For example, we can mechanically move a bar or band of illumination across

the frame one or more times during each frame time. Similarly, we can raster scan one or more spots of illumination, in varying order; note that we can use a relatively large spot or pattern and relatively few scan lines to get the required brightness. In all of these cases, the scan pattern, orientation, and rate can be varied. In addition, the rate or range

of rates or characteristic time for pattern variations can be selected to be particularly annoying when videotaped, per above.

Similarly, we can vary or scan each illumination color (e.g. the 3 primary colors) over

different parts of the frame at different times during the frame time, again compensating

for any residual variation visible to the movie viewer where necessary by varying the

video signal to the transmission projection unit. Equivalently, we can vary the color

balance of the illumination of different parts of the frame during the frame time.

In both cases, we can either make the overall illumination or color balance as even as possible, when integrated over the frame time (and vary the video signal if required to compensate for any residual variation visible to the moviegoer), or we can deliberately

make the overall illumination or color balance uneven during each frame and have an altered video signal to compensate.

Similarly, we can vary the color balance of the overall illumination with time and vary

the video signal to the transmission projection unit to compensate; this does not defeat

attempts to videotape off the movie screen, but it does defeat attempts to tap the electrical video signal out of the projection unit. Note that the variation does not have to be

particularly large to produce an annoying result in the illicit copy.

Similarly, we can optionally have the net illumination during each frame time be uneven over the frame, and compensate for it in the video signal so no variation appears on the screen; again, the benefit is that there is never a clean video signal inside that unit; thereby foiling attempts to tap in and get a clean digital signal. Note that this variation can be done when the video signal is decoded or recovered, or if a "part A" and "part B" technique is used, it can be embedded in either or both parts. Note that a similar

technique can be applied to any of the other illumination techniques described herein;

allow a visible variation in the illumination and compensate for any residual variation visible to the movie viewer in the video signal.

In addition, one can optionally introduce variations in the video signal that do not show

up with the particular varying illumination technique used. For example, if different parts of the frame are illuminated at different times during the frame time, the video signal on the parts of the frame that are not illuminated at any given moment can be

varied arbitrarily or can be set to "dark" or "light" or anything else. None of this is visible to the theatergoer, but it will be highly visible if someone taps & records the video signal from the projection unit.

In addition, we can project very-near-UV or very-near-IR illumination patterns or

pictures on the screen as well; these are invisible to the viewer in the theater, but the UV is very visible indeed to all TV cameras, and the near DR. is very visible to solid-state TV

cameras; the UV shows up as blue/violet; the IR shows up as red. Again, we can pick an annoying or distracting pattern or variation rate; additionally, we can project information; one option is to project the word "STOLEN"; again, these patterns, variations, or information would show up on any illicit copy made with a video camera but would be invisible to the theatergoer. Note in addition that the eye has very poor sensitivity to light at or near the violet or red edge of the visible, whereas the response of most cameras is more "ideal"; accordingly, we can also project patterns in those spectral regions with

little or no visibility to the moviegoer but plenty of visibility on any illicit videotaped copy. If necessary, we can vary the video signal to the transmission projection unit to

compensate for any residual effect visible to the moviegoer.

Note that these unorthodox scan techniques and varying illumination techniques also provide further protection against attempts to tap into the electronic signal inside the

playback unit; a video signal that produces these unorthodox scans or that provides any required compensation for any residual variation visible to the movie viewer from the varying illumination techniques or which is invisible when used with said varying illumination techniques is a signal that cannot be played back on conventional video

equipment.

Note further that the above techniques can be combined.

Note further that we can vary any of the above techniques with time using a variety of techniques, including but not limited to: in response to information transmitted along with the video signal, or in response to information stored in a portable storage medium or portable electronic device or in projection unit, or in a processor or computer connected to same. In addition, we can vary any of the above techniques in response to a one-time-pad or in response to the bit-stream output of an encryption algorithm.

Note further that one can implement a "part A" / "part B" technique wherein "part A" is the video information, transmitted in the same order as the scrambled scan, and "part B" is the scan order, or vice-versa. Similarly, "part A" can be a video signal that is compatible with or which cancels the variation due to a varying illumination, and "part

B" can be the signal for that varying illumination. Other techniques wherein the video signal is scrambled or distorted or has a spatial or temporal pattern-type or noise-type

variation imposed upon it, and said scrambling or distortion or variation is removed by

the way in which it is projected are also suitable. In other words; in the first part of this application, we described techniques wherein electronic means were used to render the video signal unviewable; the signal then being restored to viewability by electronic means as well; here we have described analogous techniques where it is restored to viewability by optical means, e.g. in the projection unit.

Note further that all of these varying illumination techniques can be applied to the projection of conventional movie films. For example, we can, as previously recited, scan a bar or band of illumination across the frame one or more times during each frame time, or raster scan one or more spots of illumination over the frame area one or more times during each frame time. Similarly, as previously recited, we can vary or scan each illumination color over different parts of the frame, or, equivalently, vary the color balance of the illumination of different parts of the frame during the frame time. So long as the average illumination, integrated over each frame time, is uniform and white (no excess of any color), the people watching the movie on the screen will see no difference. However, as previously recited, an illicit videotape of the projected movie would be annoying and virtually unwatchable.

Note further that any residual variation visible to the theatergoer can be canceled or compensated by changing the movie film, e.g. by introducing an opposite or canceling

variation in same, as previously recited for the electronic versions of movies.

Note yet further that, as previously recited for the electronic movie case, we can

deliberately vary the illumination or color balance over the area of the frame. In this case, we can introduce a compensating variation in the movie film or print to cancel said variation, said variation being exactly analogous to that previously recited as being intro- duced into the video recording or data or transmission. For example, in one frame, the illumination may contain an excess of red in the center of the screen, with the

corresponding frame of the movie film being color-distorted in the center to compensate; said pre-processing typically being applied in the studio or in the distribution facility that

makes the prints for distribution to the theaters. In this case, a stolen or copied print of the movie would be annoying and unwatchable as well, if projected by conventional means.

Note further that these means can be varied from frame to frame; the required variation in the illumination source (to match the color distortions over the different frames in the movie film) may be supplied via a transmission during the showing of the movie, or via a portable storage medium or portable electronic device, or stored in the projection unit, an auxiliary unit, a local server, or any of the means previously recited for the electronic movies.

In general, all of the varying illumination techniques previously recited for electronic movies or other videos can also be applied to conventional movies on film, and any canceling, compensating, or canceled variation recited as being in the electronic signal or data or recording can instead be introduced into the film print of the movie.

Note finally that conventional movie projector designs can be modified, and many

conventional movie projectors can be retrofitted by replacing the conventional illumination unit and optics with our novel illumination unit and optics.

Claims

1. A method of secure data transmission comprising:

dividing the data transmission into first and second parts; storing said first part of said data transmission on a physical portable storage media; delivering said physical media to an intended recipient of said data transmission; and electronically delivering said second part of said data transmission to said intended recipient.

2. A method of secure data transmission comprising: encrypting a data transmission; delivering said encrypted data transmission to an intended recipient, electronically; providing decrypting means on a physical portable storage media; and delivering said portable storage media to said intended recipient.

3. A method of preventing illicit video capturing of projected moving images by moving image capturing devices, comprising: projecting a moving image having variations which are reproduced by image capturing devices; and said projected moving image appearing normal to the unaided human eye.