WO2015060847A1

WO2015060847A1 - Frame interleaving for display of digital cinema content on multiple screens by a single projector

Info

Publication number: WO2015060847A1
Application number: PCT/US2013/066512
Authority: WO
Inventors: Sek Loong Chai
Original assignee: Thomson Licensing
Priority date: 2013-10-24
Filing date: 2013-10-24
Publication date: 2015-04-30

Abstract

A method and system for projecting separate digital cinema compositions on individual screens from a common digital cinema projector commences by projecting, through a controllable beam splitter mechanism, interleaved frames of a plurality of digital cinema compositions. The controllable beam splitter is controlled to direct the frames of each separate digital cinema composition to appear on a corresponding individual screen.

Description

FRAME INTERLEAVING FOR DISPLAY OF DIGITAL CINEMA CONTENT ON MULTIPLE SCREENS BY A SINGLE PROJECTOR

TECHNICAL FIELD

This invention relates to the display of digital cinema content.

BACKGROUND ART Digital cinema now has become the preferred mechanism for distribution of motion pictures to movie theaters. In the past, movie studios incurred significant expense in connection with the production of celluloid release prints and their distribution to individual theaters. Now, with the ability to replicate one or more feature length motion pictures in digital form on a single hard disk drive, movie studios have significantly reduced their distribution costs by migrating to digital cinema.

However, the advent of digital cinema has forced individual theaters to replace their analog projectors with significantly more expensive digital cinema projectors. For a multiscreen theater, this cost becomes substantial. In addition to the cost of the projectors, a movie theater upgrading to digital cinema must also provide the necessary infrastructure to support the digital cinema projectors, including, but not limited to digital cinema severs for storing content.

Thus, a need exists for reducing the number of projectors needed in a multi-screen theater for displaying digital cinema content. BRIEF SUMMARY OF THE INVENTION

Briefly, in accordance with a preferred embodiment of the present principles, there is provided a method for projecting separate digital cinema compositions on individual screens from a common digital cinema projector. The method commences by projecting, through a controllable beam splitter mechanism, interleaved frames of a plurality of digital cinema compositions. The controllable beam splitter is controlled to direct the frames of each separate digital cinema composition to appear on a corresponding individual screen. BRIEF SUMMARY OF THE DRAWING

FIGURE 1 depicts a block schematic diagram of a system in accordance with a preferred embodiment of the present principles for projecting separate digital cinema compositions onto individual screens.

FIGURE 2 depicts a flow diagram of a method in accordance with a preferred embodiment of the present principles for projecting separate digital cinema compositions onto individual screens. DETAILED DESCRIPTION

FIGURE 1 depicts a system 10, in accordance with a preferred embodiment of the present principles of a digital cinema projection system 10 comprised of a projector 12 having the capability of projecting separate digital cinema compositions (e.g., digital cinema movies) onto individual screens, as best exemplified in FIG. 1 by screens 14 and 16, respectively. In practice, the screens 14 and 16 reside in separate exhibition rooms in a multi-screen theater (not shown).

The projector 10 comprises a conventional digital cinema projector, as available from one of several manufacturers, including Sony, Barco, Christie and NEC. The structure and operation of the projector 10 remain unimportant with the exception that the projector 10 must possess the ability to project digital cinema composition at a multiple of the prescribed frame rate, a common feature of current day digital cinema projectors. Thus, in the case of digital cinema compositions having a prescribed frame rate of 24 feet per second, (24 fps), the digital cinema projector 10 must have the capability of projecting digital cinema compositions at twice that rate or 48 fps. Similarly, for digital cinema compositions having a higher frame rate (e.g., 48 fps or 60 fps), the digital cinema projector 10 must possess the ability to project such compositions at 96 fps or 120 fps, respectively.

The digital cinema system 10 includes a digital cinema server 18, such as

manufactured by one of Doremi Labs, Sony, and dcinex, for example. The digital cinema server 18 supplies individual digital cinema compositions, combined in a single digital file 20, to the digital cinema projector 10. In accordance with the present principles, the digital file 20 provided by the digital cinema server 18 to the digital cinema projector has the frames of the individual cinema compositions interleaved in temporal succession. In the illustrated embodiment of FIG. 1 wherein the digital cinema projector displays two separate digital cinema compositions onto the screens 14 and 16, respectively, the file 20 will comprise two digital cinema compositions with the frames interleaved. Thus, frames 1, 2, 3, 4... of the file 20 comprise successive interleaved frames of Digital Cinema (DC) composition 1 and Digital Cinema Composition 2 so that a frame of DC2 follows a frame of DC1 which in turn follows a frame of DC2 and so on.

In accordance with the present principles, the digital cinema system 100 comprises a controllable beam splitter 22 situated in the optical path of the projection beam 24 of the digital cinema projector 10 for alternately directing the projection beam onto the screens 14 and 16, respectively. In practice, the controllable beam splitter 22 can take the form of a Digital Light Projection (DLP) device manufactured by Texas Instruments for alternately operating under control of the digital cinema projector 12.

As depicted in FIG. 1, the digital cinema projector 12 controls the controllable beam splitter 22 to display alternate frames the digital file 20 onto the screens 14 and 16. As noted previously, the frames of the file 20 comprise interleaved frames of the digital cinema compositions 1 and 2. Thus, the digital cinema projector 10 will successively project the odd frames (frames 1, 3, 5...) of the file 20 onto the screen 12. The odd frames of the file 20 comprise successive frames (e.g., frames 1, 2, 3, 4...) of the digital cinema composition 1. When not projecting the odd frames of the file 20 onto the screen 14, the digital cinema projector 20 will successively project the even frames (frames 2, 4, 6...) of the file 20 onto the screen 16. The even frames of the file 20 comprise successive frames (e.g., frames 1, 2, 3, 4...) of the digital cinema composition 2. In this way, the audience viewing the screen 14 will observe successive frames of the digital composition 1 whereas the audience viewing the screen 16 will observe successive frames of the digital composition 2.

FIGURE 2 depicts a flow diagram of a method in accordance with a preferred embodiment of the present principles for projecting separate digital cinema compositions onto individual screens. As seen in FIG. 2 the method commences by first projecting, into the controllable beam splitter 24, successive interleaved frames of the plurality of digital cinema compositions (Step 200) . The controllable beam splitter 24 is controlled to direct the frames of each separate composition on a screen (step 202).

As noted previously, the projector 10 operates at twice the frame rate of the digital cinema compositions supplied from the digital cinema server 18. Thus, in the illustrative embodiment of FIG. 1, assuming the digital cinema compositions 1 and 2 each have frame rates of 24 fps, the digital cinema projector 10 will operate at a frame rate of 48 fps. Thus, the odd and even frames of the digital file 20 (comprising the successive frames of the digital cinema compositions DC1 and DC2, respectively) will appear on the screens 14 and 16 at a rate of 24 fps, so the audience members observing each screen will see the projected digital cinema composition at the normal frame rate. To compensate for any loss of brightness associated with projecting the projector beam through the controllable beam splitter 22, the projector 12 may need to operate at a higher than usual brightness.

The digital cinema projection system of FIG. 1 affords the advantage of projecting two separate digital cinema compositions onto the corresponding screens 14 and 16, respectively, using a single digital cinema projector. The digital cinema system 10 could easily project three or more digital cinema compositions, provided that the frames of such compositions were appropriately interfaced in the digital file 20, and the digital cinema projector operates at the corresponding multiple of the frame rates of the separate digital cinema compositions. The angle of dispersion and the switching rate of the controllable beam splitter 22 could ultimately limit how many separate digital cinema compositions a single projector could project onto individual screens.

Rather than project two different movies, the system 10 of FIG. 1 could also create higher resolutions. For example, the combination of the projector 12 and the controllable beam splitter 22 could project multiple 2K resolution images (overlapped) on a common screen to create a 4K or 6K image.

The foregoing describes a technique for projecting separate digital cinema

compositions onto the corresponding individual screens using a single digital cinema projector.

Claims

CLAIMS 1. A method for projecting a plurality of digital cinema compositions from a common digital cinema projector, comprising the steps of:

projecting, through a controllable beam splitter mechanism, successive interleaved frames of the plurality of digital cinema compositions; and

controlling the beam splitter to direct the frames of each separate composition on a screen.

2. The method according to claim 1 wherein the successive interleaved frames of the plurality of digital cinema compositions are projected at a frame rate which is a multiple of a frame rate of each of the plurality of digital cinema compositions and wherein the controllable beam splitter is controlled so the frames of each separate composition appear on a separate screen.

3. The method according to claim 2 wherein the projecting step comprises projecting two separate digital cinema compositions at a frame rate twice the individual frame rate of each composition.

4. The method according to claim 1 wherein the projecting step comprises projecting separate digital cinema compositions of a first resolution to overlap on a common screen to create a higher-resolution digital cinema composition.

5. A digital cinema system, comprising:

a digital cinema server for providing a plurality of digital cinema compositions whose frames are interleaved with each other;

a digital cinema projector for successively projecting; the interleaved frames of the plurality of digital cinema compositions; and

a controllable beam splitter for directing the suggestively projected interleaved frames of the plurality digital cinema compositions so successive frames of each separate digital cinema composition appears on a screen.

6. The digital cinema server system of claim 5 wherein the projector projects the successive interleaved frames of the plurality of digital cinema compositions at a frame rate which is a multiple of a frame rate of each of the plurality of digital cinema compositions and wherein the projector controls the controllable beam splitter so the frames of each separate composition appear on a corresponding individual screen.

7. The digital cinema system of claim 6 wherein the projector projects two separate digital cinema compositions at a frame rate twice the individual frame rate of each composition.

8. The digital cinema system of claim 6 wherein the projector projects separate digital cinema compositions of a first resolution to overlap on a common screen to create a higher-resolution digital cinema composition.