GB2525015A

GB2525015A - A display apparatus and method

Info

Publication number: GB2525015A
Application number: GB1406452.1A
Authority: GB
Inventors: Mike Beadman; Ben Crundwell; James Baker
Original assignee: MOTIONLED TECHNOLOGY Ltd
Current assignee: MOTIONLED TECHNOLOGY Ltd
Priority date: 2014-04-10
Filing date: 2014-04-10
Publication date: 2015-10-14
Also published as: GB201406452D0

Abstract

A system for displaying video to passengers in a vehicle 6 travelling along a path 1, e.g. in a railway tunnel, comprises a sensor arrangement 4 to determine the speed of the vehicle, a plurality of display apparatuses 30 arranged along the path and a control arrangement 5. Each display apparatus is controlled to generate an apparently stationary video by persistence of vision. Furthermore, the display apparatuses are controlled to omit to display at least one frame of the video when the speed of the vehicle is less than a predefined speed for a period of time and/or to add or repeat at least one frame of the video when the speed is greater than the predefined speed for a period of time. The frame rate of the video is dependent on the speed of the vehicle and omitting or adding frames maintains the overall length of time the video is displayed. The display apparatuses may be irregularly spaced. If the sensors determine that the vehicle is stationary or near stationary, each display apparatus may be controlled to display a video.

Description

A DISPLAY SYSTEM AND METHOD

FTELD OF THE INVENTION.

[04)4)1] The present invention relates to a display system and method in which the passing of vehicles is sensed for the control of the display of apparently stationary video images to passengers in the vehicles.

BACKGROUND INFORMATION

[00021 it is well known to display images to passengers in vehicles travelling along a path. Advertisements and information can be displayed as static or video images. When the vehicle is moving fast within a confined structure such as a tuilnel, images displayed at fixed positiolls on the tunnel walls move past [lie visual field of the passengers too quickly to be visible. Prior methods to overcome this problem include illuminating images positioned alollg the tunnel in time with the movement of the vehicle so as to cause the images to appear at a stationary position in the passengers field of view Such prior methods include the use of electronic displays positioned along the tunnd and controlled to generate an output in time with the passing of the vehide. The prior art approaches have particularly been applied to trains or underground metro systems where the vehicle is confined to a track and the speed at which it travels are usuafly constrained.

SUMMARY OF THE INVENTTON

[9003] One aspect of the invention provides system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of display apparatuses arranged adjacent to and along the path to output the video frames to he visible to the passenger: at least one sensor arrangement to detect the vehicle passing alollg the path to generate an output aild a controller arrangement adapted to control the display apparatuses to output video frames to gellerate an apparently stationary video visible to die passenger dependent upon the sensor output, aild to coiltrol the display apparatuses to omit to display at least one frame of the video when the sensor output is indicative that the speed of the vehicle is less than a predefined speed for a period of time and/or to add or repeat at least one frame of the video when the sensor output is indicative that the speed of the vehicle is greater than the predefined speed for a period of time.

[0004] Another aspect of the invention provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprishig sensing the vehicle passillg along the path using at sensor arrangements arranged along the path to generate a sensor rnitput; controlling a plurality of display apparatuses arranged adjacent to and alofig the path to output video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output; and controlling the display apparatuses to omit to display at least one frame of the video when the sensor output is indicative that the speed of the vehicle is less than a predefined speed for a period of time and/or to add or repeat at least one frame of the video when the sensor outinit is indicative that the speed of the vehicle is greater than the predefined speed for a period of time.

[0905] Another aspect of the invention provides a system for displaying video frames of a video to a passenger in a vehicle travefling along a path, the system comprising a plurality of display apparatuses arranged adjacent o and along the path to generate the video frames to he visible to the passenger, at frast some of said disphuy apparatuses being arranged at irregular spacings and known positions along the path; at east one sensor arrangement to detect the vehicle passing along the path to generate an output; and a controller arrangement adapted to control the display apparatuses to output video frames on the display apparatuses to generate an apparently stationary video visible to the passenger dependent upon the output of the at least one sensor arrangement, and to further control the timing of the output of frames by the at least some of said display apparatuses depeildent upon the known positions of the at least some of said display apparatuses.

[0006] Another aspect of the invention provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising detecting the vehide passing along the path using at least one sensor arrangement to generate an output controlling a plurality of display apparatuses arranged adjacent to and along the path to outpLlt video frames on the display apparatuses to generate an apparently stationary video visible to the passenger dependent upon the oLItpLIt of the at least one sensor arrangement: wherein at least some of said display apparatuses are ananged at irregular spacings and known positions along the path, and the timing of the output of frames by the at least some of said display apparatuses is controlled dependent upon the known positions of the at least some of said display apparatuses.

[00071 Another aspect of the invention provides a system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of display apparatuses arranged adi acent to and along the path to output the video frames to be visible to the passenger; at least one sensor arrangement to detect the vehicle passing along the path to generate an output: and a controller arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output, to contrd adjacent display apparatuses in a group to each sequentially output the same video frame, and to control adjacent groups of display apparatuses to disp'ay sequential video frames.

[000$] Another aspect of the invention provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising detecting the vehide passing along the path to generate a sensor output; and controlling a plurality of display apparatuses arranged adjacent to and along the path to generate the video frames to he visiffle to the passenger dependent upon the sensor output, by controlling adjacent display apparatuses in a group to each sequentially output the same video frame, and controlling adjacent groups of display apparatuses to display sequential video frames.

[09091 Another aspect of the invention provides a system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of two dimensional display apparatuses arranged adjacent to and along tile path to output the video frames to he visible to the passenger; at least one sensor arrangement to detect the vehicle passing along the path to generate an output; and a controller arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visible to the passenger by outputting a sequence of video frames (WI sequentially arranged display apparatuses along the path Ill dependence upon the sensor output, wherein the controller arrangement is adapted in respouise to a determination that the vehicle is stationary or near stationary to control the display apparatuses adjacent to the vehicle to each display a video.

Another aspect of the invention provides a method of displaying video frames of a video to a passeuiger in a vehicle travelling along a path, the method comprising detecting the vehicle passing along the path to generate a output and controlling a plurality of two dimensional display apparatuses arranged adjacent to and along the path to output video frames to generate an apparently stationary video visible to the passenger by rnitputting a sequence of video frames on sequentially arranged display apparatuses along the path in dependence upon the sensor output, and, in response to a determination that the vehicle is stationary or near stationary controfling the display apparatuses adjacent to the vehicle to each display a video.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure lisa schematic diagram illustrating a display system of one embodiment of the invention; [0911] Figure 2 is a schematic diagram of a display apparatus of one embodiment of the invention; [00121 Figure 3 is a schematic diagram illustrating the operation of a columnar display to generate a video frame in the visual field of a passenger passing along a path; [00131 Figure 4 is a schematic diagram illustrating a display system of another embodiment of the invention; [04)14] Figure 5 is a schematic diagram of a display apparatus of another embodiment of the invention; [0015] Figure 6 is a schematic diagram to illustrate the matching of the frame rate to the rate of passing the displays apparatuses when a vehicle is travelling at a predetermined speed for the display of a stationary video of a predetermined leuigth to a passenger according to one embodiment; [0016] Figure 7 is a schematic diagram to illustrate how the display apparatuses are controlled to drop a frame when the vehicle is travelling slower than the predefined speed to avoid lellgthening the time taken to display the video to the passenger according to one embodiment; [0017] Figure 8 is a schematic diagram to illustrate how the display apparatuses are controlled to add or repeat a frame when the vehicle is travelling faster than the predefined speed to avoid shortening the time taken to display the video to the passenger according to one embodiment; [90181 Figure 9 is a schematic diagram to illustrate how the display apparatuses which are positioned irregularly are controlled to time the display of each frame of a video to avoid positional jitter of the disphuyed the video as viewed by the passenger according to one embodiment; [9019] Figure 10 is a schematic diagram to illustrate how the display apparatuses are controlled when the vehicle is travelling at half the predefined speed to avoid lengthening the time taken to display the video to the passenger according to one embodiment: and [9020] Figure II is a schematic diagram to illustrate how display apparatuses can be grouped in pairs to repeat a frame each when the vehicle is travelling at half the predefined speed to increase the intensity of the viewed frames according to one embodiment.

DETAILED DESCRIPTION

[00211 In the followillg detailed description, reference is made to the accomp&iying drawings that form a part hereof, and in which is shown by way of illustration specific embodiments in which the inventive subject matter maybe practiced. These embodiments are described in sufficient detafi to enable those skilled in the art to practice them, and it is to he understood that other embodiments maybe utilized and that structural, logical, and electrical changes may he made without departing from the scope of the inventive subject matter. Such embodiments of the inventive subject matter may be referred to, individually and/or collectively, herein by the term "invention" merely for coilvenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept if more than one is in fact disclosed.

[00221 The following description is, therefore, not to be taken in a limited seilse, and the scope of the inventive subject matter is defined by the appeilded claims.

[09231 In the following embodiments, like components are labeled with like reference mumerals.

[0924] The functions or algorithms described herein are implemented in hardware, software or a combination of software and hardware in one embodiment.

The software comprises computer executaffle instructions stored on computer readable media such as memory or other type of storage devices. Further, described functions may correspond to modules, which may he software, hardware, firmware, or any combination thereof. Multiple functions are performed in one or more modules as desired, and the embodiments described are merdy exampfrs. The software is executed on a digital signal processor, ASTC, microprocessor, or other type of processor operating on a system, such as a personal computer, server, a router, or other device capahfr of processing data including network interconnection devices.

[0925] Some embodiments implement the functions in two or more specific interconnected hardware modules or devices with related control and data signals communicated between and through the modules, or as portions of an application-specific ifitegrated circuit. Thus, the exemplary process flow is applicable to software, firmware, and hardware implementations.

[04)26] The system and method of embodiments of the invention generate apparently stationary video frames visible to a passenger, which comprises a video which appears to a passenger in a moving vehicle in a stationary location viewed from a position in the vehicle e.g. out of a window. Although the term stationary' is used, it is to he understood that this is not an absolute term and the image visible to the passengers may move about slightly, due to factors such as, variations in the speed of the vehicle, inaccurate display apparatus positioning, or delays in timing control signals. The apparent stationary image can be achieved by controlling display apparatuses arranged along a path to output video frames to generate an apparently stationary video visible to the passenger by outputting a sequence of video frames on sequentially arranged display apparatuses along the path in dependence upon the determined speed of the vehicle. The control can comprise timing of the frame output and for columnar displays (as opposed to 2D displays), the control of the timing of the output to generate the pixels rows of each frame.

[0027] The invention is applicable to any vehicle travelling along a path and carrying passengers. Embodiments are particularly applicable to passenger carrying vehides that are constrained to run along a confined path such as a track or rail structure, such as a train, tram, metro, underground transport vehicle, or mono-rail.

[092$] The invention provides for the display of images. It is particularly applicable for use in consistent ambient light conditions e.g. low ambient Ught conditions. Although it can he used at night in open locations, unless the brightness of the output of the displays are variable dependent upon the ambient light conditions, the time it can he operated is restricted. It is ideally suited for use in tunnels, where the ambient light is relatively consistent and low and the sides of the tunnel provides a convenient mounting structure. Further, the passengers are not afforded any view out of the windows except for the images from the displays, which does not interrupt their view and increases the likelihood of them watching the images. This is highly advantageous for the display of advertisements in still or moving form [0029] Figure 1 illustrates a first embodiment of the invention. A vehicle comprising a train bin this embodiment is traveling in a direction indicated by the arrow along a path, which in this embodiment is defined by a track structure I and which acts to confine tile path of the train 6. The train 6 carries passengers along the path and has windows 7 through which the passengers can view the adjacent area.

Lying along and adjacent to the track structure I at a level with the windows 7 of the train 6 are display apparatuses 2 for generating output images to be visible to the passengers in the train 6 as they pass the display apparatuses 2. In this embodiment the display apparatuses 2 comprise columnar display apparatuses, which comprise a column of display elements, such as disclosed in US6,169,368, the content of which is hereby incorporated in its entirety by reference. Each row of the column of display elements generates a complete row of a displayed image by sequentially outputting image pixels timed to generate a correct apparent image width to the passengers dependent upon the speed of the vehicle. The column of display elements has a row dimension that is much less than the width of the image to be displayed to the passengers. The movement of the viewing passengers past the display apparatuses 2 acts as a r&ative scanning of the output image pixels in the horizontal direction to play out the image across the width of a display area. A row can comprise a single display element, such as an ROB Light Emitting Diode (LED), or a few such dements acting together. The benefits of using such columnar display apparatuses 2 compared to conventiona' full 2D display apparatuses are that the displays take up less space and hence do not obstruct access to structures athng the side of the track structure I, they have a lower surface area and are hence less prone to damage such as from stones, and can he manufactured at lower cost.

[0030] The disphuy apparatuses 2 can he mounted on the side of a tunn& through which the train 6 is passing and are connected together and to a control unit 5, which can comprise a digital apparatus such as a computer. The control unit 5 call act to control the display apparatuses 2 to output the images at the correct time so that a apparently statiollary video is visible to the passengers at a position relative to the window 7 of the train 6 and with the correct aspect ratio. For the display of a video, the first disphty apparatus 2 that the train 6 comes to can display a first frame of the video, the next display apparatus the second frame and so on. The display of the frame needs to he timed to the speed of the train 6 so as to appear at the correct position in the window 7 of the train 6. In this embodiment a sensor arrangement 4 is provided at a position along the path to detect a front part of the train before it passes the first display apparatus. The sensor arrangement 4 can provide a train speed signal, which can be used by the control unit 5 or by the display apparatuses 2 using separate independent display controllers to control each display apparatus 2 to output the correct image at the correct time that the trail 6 passes. Hence, the sensor arrangement 4 can provide an initial train speed to be used for control. A method of sensing the speed of the train after passing the sensor arrangement 4 is described in copending application number GB 1406447.1, entitled "A display System and Method" filed on the same day as this application, the contents of which are hereby incorporated by reference. The sensor arrangement 4 can output a signal directly related to the speed of the train 6, or it can output a signal indicating that the train has passed the sensor. A sensor arrangement 4 with a plurality of sensors spaced a known distance apart or a plurality of sensors spaced a known distance apart can then he used to output a signal that can he used to calculate the speed of the train. In this embodiment where a single sensor arrangement 4 is provided, the arrangement can provide a timing signal to indicate that the train has passed as well as the speed signa', since a signal indicative of speed on its own is not enough e.g a Doppler based radar can he used to provide a speed signal and a position signal can he deduced from the output when the speed drops to zero. Tn an akernative arrangement, two proximity detectors (e.g. optical sensors, magnetometers or even tactile sensors) of known spacing can detect the passing of the train and either can give a position signal and the combination of both signals can give a speed signal due to their Imown separatioll.

[00311 In this embodiment only one sensor arrangement 4 may be used, or as described herein after, multiple sensor arrangements can be used by for example associating sensor arrangements with each display apparatus.

[0032] The timing of the output by the display apparatuses can he controlled using the determined speed and a reference, sLich as the time the vehide passed the first or any sensor arrangement together with the known or assumed position of the display apparatuses. The speed determination enables a prediction of the frame required to he output by each display apparatus so that the display apparatus can he ready to output it as the vehicle passes. If the speed of the vehicle reduces or increases, the predicted frame that is determined to be required to be output will need to be changed. To enable this, each display apparatus stores a full copy of the video so that the required frame can be selected for output.

[09331 The timing of the output of the display apparatuses can be controlled simply based on the timing of sigilals from the sensor structure 4, or from a plurality of sensor arrangements, without actually determining a figure for the speed of the vehicle. The control can simply be based on timing and the known or predetermined locations of the display apparatuses along the path.

[09341 The control unit 5 can be used to store a library of images for the display apparatuses 2 and such images can be downloaded to appropriate display apparatuses 2 when it is desired to change the disphuyed images. The control unit 5 can act as a central controller to control the display of images or video frames by the display apparatuses 2. Alternatively, each display apparatus 2 can act autonomously to control the output of the image or videos frame in dependence upon the received output of the sensor arrangement 4. Tn sLich an embodiment, the contr I unit 5 can he used for initial configuration of the display apparatuses 2 and to provide software and video updates to the display apparatuses 2.

[0935] Figure 2 illustrates a display apparatus 2 according to one embodiment which incorporates a sensor circuit 22 for processing signals for an associated sensor arrangement. The sensor arrangement can he associated with a display apparatus 2 by being illcorporated within a housing of the display apparatus 2 or attached thereto. It may alternatively simply be positioned close by at a known distance.

[04)36] The disp'ay apparatus includes a microprocessor 21 acting as a display controller to control the columnar LED display array 20 to display images stored in a memory 24 in dependence upon the signal from the sensor circuit 22. A network connector 23 is connected to the microprocessor 21 to enable data to he passed to the control unit 5 and to other display apparatuses 2 via a communication network such as an Ethernet. In particular, the sigilal from the seuisor circuit can be transmitted to all of the display apparatuses 2 to be used by them to control the display of images.

[0037] This anmigernent ellables a sensor arrangement associated with each display apparatus to detect the passing of a front part of the train 6 and to output a sigilal indicative of the position of the train 6 or to output a train speed signal. The signals from the sensor arrangements can hence be used to monitor the train speed as it passes each display apparatus 2 (or simply a time of the passing of the train) and the signal can be used by each display apparatus 2 to adiust the output images accordingly. The association of the sensor arrangements with the display apparatuses 2 avoids the need for the installation of separate components and provides regular train speed update signals.

[093$] Figure 3 illustrates of tile operation of a co'umnar display apparatus of the first embodiment to generate a video frame in the visual fiEld of a passenger passing along a path. A columnar display can comprise a single column of RGB LEDs or a co'umn of each colour LED for example. It can also comprise a more than one LED in a row. The display apparatuses are positioned adjacent to and along a path of a vehicle, such as along a tunn& wall of a train or metro, and they are spaced by a distance D. The distance is predefined by the frame rate Fr of the video and a predefined vehicle speed S1,, which can he a maximum permitted vehide speed or an average train vehide for vehicles passing along the path. Hence the distance between with display apparatuses is defiled by [00391 D = Sp I Fr [0040] If the maximum speed of the train is lOOkmIhr (27m1s) and the frame rate is 25Hz, the spacing D should be 1.1 irn. For a videos image frame having as aspect ratio of 16:9, if a display apparatLis has a height of I m to give a video image frame of height I m, the width of the video image frame is I.78m. The apparent video image frame is wider in this example than the spacing between the display apparatuses. In such an example, the display apparatus for the next frame comes into view to a passenger and this starts outputting the next video image frame. So the last third of the first video image frame is still being displayed while the first third of the next video image frame starts displaying. if the display apparatuses are shorter relative to their spacings D, there will be no overlap of the output of video image frames.

[00411 The passenger can hence see a sequence of displays along and adjacent to the path e.g. on a tunnel wall. The video frame being displayed by each display apparatus in the sequence along the path will display sequential frames and hence neighbouring display apparatuses will display adiacent frames in the video sequence. In order to generate the frame, the columnar display apparatus generates one colunm (or a few colunms) of pixels repeatedly to scan out the frame rows. The scan out rate is dependent upon the speed of the vehicle. If the vehicle slows, the scan out rate wifi need to slow to keep tile apparent width of the image frame constant.

[9042] Figure 4 illustrates a display system according to another embodiment, in which the display apparatuses comprise 2D display apparatuses 30.

The structure and operation of this embodiment is otherwise similar to the strllctLlre and operation of the embodiment of figure I. The structure of the disphty apparatuses 30 of this embodiment is illustrated in figure 5. In this embodiment, the microprocessor 21 controls a 2D display 200 which can comprise a conventional LED display, or a plasma display for example. The structure and operation of this embodiment are otherwise the same as described for the first embodiment with reference to figure 2, with the exception that there is no need to provide for control of the output of the scanned column of pixels for a frame. The 2D displays generate a full frame output rather than a partial frame colunmar output which is repeatedly output to create the pixel rows. The benefit of the use of 2D displays is that each 2D display can display a full video as a sequence of video frame in a conventional manner when the vehicle is static or near static e.g. moving at less than I or 2 mph.

[0043] In the embodiments of figures 1 to 5, a sing'e part of the train 6 is detected using muhiple sensors arrangements spaced at a r&atively short distance apart. The distance apart can depend upon the maximum speed of the train 6.

[9044] The provision of a sensor arrangemeilt associated with each display apparatus 2 enables the sensor arrangemeilt to be used to trigger the switching on of the first image for display to the passengers in the first window 7 of the train 6. In a twine!, the displays can be inactive uiitil a train 6 passes to avoid distracting a driver of the train 6.

[0045] In an alternative embodirneiit, a sensor arrangement can be placed on the track to detect the passing of the wheels of the train. The sensor arrangement will hence output signals over the length of the train as the wheels pass. This reduces the number of sensor arrangements required but requires them to be fixed to or associated with the track.

[09461 Figure 6 is a schematic diagram to illustrate the matching of the frame rate to the rate of passing the displays apparatuses when a vehicle is travelling at a predetermined speed for the display of a stationary video of a predetermined length to a passenger according to one embodiment.

[0947] Eacb sequential frame of a video to he viewed by a passenger at a fixed position relative to the vehicle is output by eacb sequential disp'ay. Tn order for this to occur, the spacing of the disp'ays must match the speed of the vehicle divided by die video frame rate. Hence, if for example the vebicle is travefling at 60km/br, and die frame rate is 30Hz, the spacing of the displays must he O.5556m.

In order to position the displays at locations that is likely to provide for die correct display of the frames, a speed of the vehicle is predefined for use in calculating die spacing between the displays. The predefined speed can comprise an average speed of one or more vehicles passing along the path in the vicinity of the displays. This average can be the average for one vehicle passillg along the path maiiy times or the average speed for multiple vehicles. This arrangement aims to have the displays arranged at the most likely correct position. Alternatively, the predetermined speed can comprise a maximum permitted speed of a vehide passing along the path in the vicinity of the displays e.g. a legal speed limit defined by law or a speed limiter device of the vehicle. This arrangement aims to ensure that there are sufficient displays along the path to display the required video.

[0048] If a video of 15 seconds is to be displayed at a frame rate of 30Hz along a path, if ouie frame is displayed by each display, 450 displays are required. if they are positioned with a spacing of 0.5556rn, the assumption is that the vehicle will ideally travel at 6Okmlhr along the path to synchronise the output of the video frames at 30Hz with the vehicle passing by the displays at a rate of 30/sec (as shown in figure 5).

[90491 When the vehicle is travelling at less than the predefined speed, in order to keep the length of the video (i.e. the time taken to play back the video frames) substantially constant, the video frames must be played out using less displays since the vehicle will pass less displays in the allocated time for the video.

Such a situation is illustrated in figure 7. In order to play out the video and keep the length of the video substantially constant, frames must he periodically omitted i.e. not displayed to the passenger. The omission of the occasional frame in a video does not greatly affect the quality of the video as perceived by the passenger [9050] As shown in figure 7, the fourth frame is not disp'ayed by the fourth display. Tnstead, the fourth display jumps to the fifth frame to avoid the timing of the output of the frame lagging too far behind. Frames 6, 7 and 8 are then displayed by displays 5, 6 and 7. As shown in this embodiment, the displays are controlled to omit a frame when the controfler arrangement determines that the timing of the output of the frames is lagging behind by a fraction of a display e.g. 50% as shown in figure 7. In an alternative embodiment, the controller arrangement can wait until the timing of the output of a frame becomes a whole display distance behind before omitting or jumping a frame.

[0051] If the displays are spaced based on the predefilled vehicle speed of 60km/hr for a video frame rate of 30Hz (i.e. at O.5556rn), and the actual determined speed of the vehicle is 54km/br, this represents a 10% reduction in speed and hence every 10th frame must he omitted. More generally this can he described as every n frame needs to he dropped, skipped or omitted when S1, >S: [0052] SaUH/n)Sp [0053] where S is the actual determined speed, Si' is the predefined speed, and n is an integer.

[0054] Hence n = 1/ (l-S,./S, [0055] In order to be able to display different frames of a video when the train changes speed, either a central controller provides the required video frame data to each display apparatus or each display apparatus stores a plurality of frames and even the whole video.

[0056] When 2D displays are used in the embodiment of figure 7, since the frames of the video will be played out over fewer display apparatuses due to the slow speed of the vehicle, there are display apparatuses at the far or distal end of the path that are not required to play the video. In such a situation, rather than not use these displays, the controller arrangement can control the display apparatuses to display images such as advertisements or public service information.

[0057] V/hen the vehicle is travelling at more than the predefined speed, in order to keep the length of the video (i.e. the time taken to play back the video frames) substantially constant, the video frames must he played out using more displays since the vehicle will pass more displays in the allocated time for the video.

Such a situation is illustrated in figure 8. In order to play out the video and keep the length of the video substantially constant, frames must be periodically repeated i.e. displayed twice to the passenger. The repetition or addition of the occasional frame in a video does not greatly affect the quality of the video as perceived by the passenger.

[0058] As shown in figure 8, the fourth frame is displayed by both displays 4 and 5 to avoid the timing of the output of the frame getting ahead too far behind.

Frames 5, 6, 7 and 8 are then displayed by displays 6, 7, 8 and 9. As shown in this embodiment, the displays are controlled to repeat or add a frame when the controller arrangement determines that the timing of the output of the frames is ahead behind by a fraction of a display e.g. 50% as shown in figure 8.In an alternative embodiment, the controller arrangement can wait until the timing of the output of a frame becomes a whole display distance ahead before repeating or adding a frame.

[0059] If the disjilays are spaced based on the predefined vehicle speed of ôOkmlhr for a video frame rate of 30Hz (i.e. at O.5556m), and the actual determined speed of the vehicle is 66kmlhr, this represents a 10% increase in speed and hence every 10th frame must be repeated. More generally this can be described as every 11ih frame needs to be repeated or added when Sa >S: [00601 Sa = (1+1/n)S [0061] where Sa is the actual determilled speed, S is the predefmed speed, and n is an integer.

[09621 Hence n = 1/ ((Sa/Sp)1) [00631 Figure 9 illustrates how display apparatuses which are positioned irregularly are controlled to time the display of each frame of a video to avoid positional jitter of the displayed the video as viewed by the passenger according to one embodiment.

[9064] In the previous embodiment, the positioning of the display apparatuses was assumed to he evenly spaced along the path. Tf the display apparatuses are spaced evenly at known spacings, the a'gorithm to control of the output of the video frames can make assumptions ahoLit the positions of the display apparatuses inherently in the calculations. However, in some environments it is not always possible to arrange the display apparatuses at such know regular spacings.

There maybe obstacles at the required regular spacings. For example, in a tunnel, there can he tunnel equipment e.g. signaling equipment and power equipment positioned along the side of the tunnel. Figure 9 illustrates the situation in which obstacles 100 prevent the regular positioning of display apparatuses along a path. in this embodiment, the display apparatuses are illustrated a generating a frame width W less than the inter display apparatus spacing. This provides some flexibility ill the positioning of the display apparatuses whist trying the keep the overall length along which the display apparatuses are positioned the same as for a regularly spaced configuration - [0065] In this embodiment, the positions of at frast the irregularly positioned display apparatuses must he known for the controller arrangement to he able to calcifiate the correct timing for the output of the video frames by the display apparatuses. For example, display apparatuses 2, 4 and 5 are displaced because of obstacles. Frame 6 is however omitted completely because no display apparatus can be positioned for the display of this frame.

[0066] The embodiments described with reference to figures 6 to 9 are applicable to columnar (ID) displays and 2D displays.

[0067] Figure 10 illustrates how the display apparatuses are controlled when the vehicle is travelling at half the predefined speed to avoid lengthening the time taken to display the video to the passenger according to one embodiment. As described above, frames are dropped when the vehicle is travelling slower than a predefined speed for which the spacing of the display apparatuses is set. In this example, every other frame is dropped (n=2). In such a situation when the vehicle is going very slowly and a high percentage of the frames have to he dropped, when a columnar display apparatus is used the brightness of the frames and hence the video to the passenger is reduced.

[096$] Figure 1 I filustrates an embodiment for enhancing the video to the passenger when the vehicle travels faster. This embodiment uses two columnar display apparatuses to display each frame and comprises a particular case of the embodiment described with reference to figure 8.

[0069] If the disp'ay apparatuses are positioned 1.1 Im apart to display a 1 6:9 aspect ratio video with a disp'ay apparatus height of I m, when the train passes at 1001cm/hr the frame rate is 25Hz. However, when the train slows down to 20kmlhr, the frame rate drops to only 5Hz. Such a low frame rate produces an image with a low brightness. Hence, to increase this, display apparatuses can be arranged 0.55m apart and controlled when the train speed is low as described above such that each display apparatus displays a sequential frame of the video with a frame rate of 10Hz. When the train speeds up, if the display apparatuses were controfled in the same sequential manner as described above, the frame rate wou'd he 50Hz. This is higher than required to display the video. Hence, one option is to switch off ever)' other display so that the effective spacing of the display apparatuses is 1.1 I m. Alternatively, the display apparatuses are controlled as adjacent groups of two in this embodiment. The use of a group of display apparatuses to output the same frame repeatedly as the vehicle passes enhances the brightness of the image. Hence, the output of the display apparatuses is reduced to compeilsate for this.

[00701 Although this embodiment is described with reference to having two display apparatuses repeating the same frame, in alternative embodiments, a frame could be repeated by a larger number of display apparatuses which are displayed relatively closely dependent upon the speed of the passing vehicle, e.g. 3 or 4 adjacent displays repeating the same frame in groups of 3 or 4 respectively. This enables the system to provide higher frame rates for low train speeds by using more closely arranged display apparatuses, which are then grrniped when the train speed increases to increasingly larger groups. For exampfr, in the example given above, if the display apparatuses are arranged O.28m apart, when the train is travelling at 20km/hr (5.4m/s) the frame rate is 20Hz. If the train speed drops to 10km/hr (2.7m/s) the frame rate drops to 10Hz. This is still adequate for a video image.

V/lien the train speeds up to I 00km/hr if every display apparatus were used to display a frame sequentially, the frame rate would he 96Hz. This is higher than required by the video. Hence, to attain a 24Hz frame rate, the display apparatuses could he controlled in groups of four to output the same video frame.

1190711 Thus in one embodiment of the invention, the disphuy apparatuses can he spaced dependent upon a lower speed of the vehicle and controlled to he used in groups to display the same video frame when the vehicle speed increases.

Where the group is more than two, not all of the display apparatuses of a potential group need be used. For example, if the display apparatuses could be grouped into four as described above for the specific example, not all 4 need be active for the output of the same video frame, only two for example need he controfled to output the video frame. The size of the group can he varied and controfled according to the speed such that the group gets smaller when the determined speed of the vehicle decreases.

[04)72] The advantage of using columnar or ID displays is that they are lower cost, take up less space and are easier to maintain. However, an advantage of using 2D displays is that when the controller arrangement determines that the vehicle is stationary or nearly stationary e.g. creeping along an something like 1 to 2 mile an house, the controller arrangement can control the display apparatuses adjacent to the vehicle, i.e. capable of displaying to the passengers, to display a full video on each of the 2D displays. if the vehicle is still moving slightly, obviously the displays will slowly move past the window of the vehicle. It is however a useful method of using the displays visible to the passengers when the train comes to an unexpected or unplanned stop e.g. a fault, traffic or signaling, next to those displays.

[0073] The following is a description of some generalized embodiments.

Any embodiment can be used in combination with any other embodiment.

[04)74] One embodiment provides a system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of disp'ay apparatuses arranged adjacent to and along the path to output the video frames to he visihe to the passenger: at least one sensor arrangement to detect the vehicle passing along the path to generate an output; and a controller arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output, and to control the display apparatuses to omit to display at frast one frame of the video when the sensor output is indicative that the speed of the vehide is less than a predefined speed for a period of time andlor to add or repeat at least one frame of the video when the sensor output is indicative that the speed of the vehicle is greater than the predefined speed for a period of time.

[04)75] In one embodiment the video has a length, and the controller arrangement is adapted to control the display apparatuses to omit and/or to add or repeat at least one frame to display the video to the passenger to have the ength.

[0976] In one embodiment the controller arrangement is adapted to contro' each display apparatus to display one frame of the video, and to select the frame to be displayed dependent upon the sensor output.

[0077] In one embodiment the controller arrangement comprises a separate display controller associated with each display apparatus, each display apparatus includes a memory storifig a plurality of video frames for the video, and each display controller is adapted to select the frame to be displayed dependent upon the sensor output.

[09781 In one embodiment the predefined speed comprises one of: an average speed of a plurality of vehicles traveling along the path, and a maximum permitted speed of the vehicle traveling along the path.

[90791 In one embodiment the display apparatuses are spaced apart a distance defined by a predefined speed of the vehicle divided by a frame rate of the video to he displayed.

[9080] In one embodiment the controller arrangement is adapted to contro' each display apparatus in sequence along the path to display a sequential video frame, and to omit every n1' frame when the sensor output is indicative ftat the speed of the vehicle is (I -I/n) times the predefined speed for a period of at least n times the frame rate, and/or add or repeat a frame every nth frame when the sensor output is indicative that the speed of the vehicle is (1+1/n) times the predefined speed for a period of at least n times the frame rate, where n >2.

[9081] In one embodiment when the vehicle has been determined to he travelling less than the predefined speed for a period of time, the controller arrangement is adapted to control at least one said display apparatus located at a distal part of the path and not reqifired to display video frames to display static images to the passenger.

[04)82] One embodiment provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising sensing the passing of the vehicle using at east one sensor arrangement arranged along the path to a generate sensor output: controlling a plurality of display apparatuses arranged adjacent to and along the path to outpLlt video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output; and controlling the display apparatuses to omit to display at least one frame of the video when the sensor output is indicative that the speed of the vehicle is less than a predefined speed for a period of time and/or to add or repeat at least one frame of the video when the sensor output is indicative that the speed of the vehicle is greater than the predefined speed for a period of time.

[0083] In one embodiment the video has a length, and the display apparatuses are controlled to omit andlor to add or repeat at least one frame to display the video to the passenger to have the length.

[0084] In one embodiment each display apparatus is controlled to display one frame of the video, and to select the frame to be displayed dependent upon the sensor output.

[9085] In one embodiment the control is performed by a separate display controfler associated with each display apparatus, each disp'ay apparatus stores a plurality of video frames for the video, and each display contniller selects the frame to he displayed dependent upon the sensor output.

[9086] In one embodiment the predefined speed comprises one of: an average speed of a plurality of vehicles traveling along the path, and a maximum permitted speed of the vehicle traveling along the path.

[9087] In one embodiment the display apparatuses are spaced apart a distance defined by apredefined speed of the vehicle divided by a frame rate of the video to be displayed.

[0088] In one embodiment each display apparatus is controlled in sequence along the path to display a sequential video frame, and to omit every n01 frame when the sensor output is indicative that the speed of the vehicle is (1-1/n) times the predefined speed for a penod of at least n times [lie frame rate, and/or add or repeat a frame every nth frame when the sensor output is indicative that the speed of the vehide is (1+1/n) times tile predefined speed for a period of at least n times the frame rate, where ii >2.

[9089] In one embodiment when the vehicle has been determined to he travelling less than the predefined speed for a period of time, the at least oiie said display apparatus located at a distal part of the path aild not required to display video frames is controlled to display static images to the passenger.

[0090] One embodiment provides a system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of display apparatuses arranged adjacent to and alofig the path to generate the video frames to be visible to the passenger, at least some of said display apparatuses being arranged at irregular spacings and known positions along the path; at least one sensor arrangement to detect the vehicle passing along the path to generate an outprn indicative of the position or speed of the vehicle; and a controller arrangement adapted to control the display apparatuses to output video frames on the display apparatuses to generate an apparently stationary video visible to the passenger dependent upon the oLItpLIt of the at least one sensor arrangement, and to further control the timing of the output of frames by the at least some of said display apparatuses dependent upon the known positions of the at least some of said display apparatuses.

119091] In one embodiment the controller arrangement compnses a separate display controller associated with each display apparatus, each display apparatus includes a memory storing at east one video frame for the video, and each display controfler is adapted to select the frame to he displayed dependent upon the output of the at least one sensor arrangement and each display controller of the at least some of said display apparatuses is adapted to also select the frame dependent upon the known positions of the at least some of said display apparatuses.

[0092] One embodiment provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising detecting the vehicle passing along the path using at least one sensor arrangement to generate an output indicative of the position or speed of the vehicle; controlling a plurality of disp'ay apparatuses arranged adjacent to and along the path to output video frames on the display apparatuses to generate an apparently stationary video visible to the passenger dependent upon tile output of the at least one sensor arrangement; wherein at least some of said display apparatuses are arranged at irregular spacings and kilown positions along the path, and the timing of the output of frames by the at least some of said display apparatuses is controlled dependent upon the known positions of the at least some of said display apparatuses.

[00931 In one embodiment the controlling is performed by a separate display controller associated with each display apparatus, each display apparatus stores at least one video frame for the video, and each display controller selects the frame to be displayed dependent upon the output of the at least one sensor arrangement and each display controller of the at least some of said display apparatuses also selects the frame dependent upon the known positions of the at least some of said display apparatuses.

[0994] One embodiment provides a system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of disp'ay apparatuses arranged adjacent to and along the path to output the video frames to he visiffle to the passenger: at least one sensor arrangement to detect the vehicle passing along the path to generate an output; and a controller arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output, to control adjacent display apparatuses in a group to each sequentiafly output the same video frame, and to control adjacent groups of display apparatuses to display sequential video frames.

[0095] In one embodiment the controller arrangement is adapted to group adjacent display apparatuses to adjust the number of display apparatuses in a group dependent upon the determined speed of the vehicle.

[04)96] In one embodiment the controller arrangement is adapted to adjust the nLlnlher of display apparatuses sequentially outputting the same video frame in a group dependent upon the sensor output by disabling the output of at least one display apparatus in the group.

[0997] In one embodiment the controller arrangement is adapted to adjust the number of display apparatuses in a group to one dependent upon the sensor output.

[00981 In one embodiment each display apparatus comprises a column of light sources adapted to output a columnar section of pixels in the frame, and the controller arrangement is adapted to control each display apparatus to output the colunmar secuoll of pixels multiple times to generate a frame.

[09991 In one embodiment the column of light sources is adapted to output a single column of pixels in the frame.

[091001 In one embodiment the controller arrangement comprises a separate display controller associated with each display apparatus, each display apparatus includes a memory storing a plurality of frames for the video, and each display controfler is adapted to select the frame to he displayed dependent upon the sensor output.

[09101] One embodiment provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising detecting the vehicle passing along the path to generate a sensor output and controthng a plurality of display apparatuses arranged adjacent to and along the path to generate the video frames to he visible to the passenger dependent upon the sensor output, by controlling adjacent display apparatuses in a group to each sequentially output the same video frame, and controlling adjacent groups of display apparatuses to disp'ay sequential video frames.

[00102] In one embodiment the method includes groupifig adjacent display apparatuses to adjust the number of display apparatuses in a group dependent upon the sensor output.

[04)103] In one embodiment the method includes adjusting the number of display apparatuses sequentially outputting the same video frame in a group dependent upon the sensor output by disahUng the output of at least one display apparatus in the group.

[09104] In one embodiment the method includes adjusting the number of display apparatuses in a group to one clepeildent upon the sensor output.

[00105] In one embodiment each display apparatus comprises a column of light sources to output a columnar section of pixels in the frame, and each display apparatus is controlled to output the colunmar section of pixels multiple times to generate a frame.

[00106] In one embodiment the colunm of light sources outputs a single column of pixels in the frame.

[091071 In one embodiment each display apparatus is separately controlled, each display apparatus stores a plurality of frames for the video, and the frame to be displayed is selected dependent upon the sensor output.

[091081 One embodiment provides a system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system comprising a plurality of two dimensional display apparatuses arranged adjacent to and a'ong the path to output the video frames to he visible to the passenger: at least one sensor arrangement to detect the vehicle passing along the path to generate a output; and a controller arrangement adapted to to control the di sp'ay apparatuses to output video frames to generate an apparently stationary video visible to the passenger by outputting a sequence of video frames on sequentially arranged display apparatuses along the path in dependence upon the sensor output, wherein the contniller arrangement is adapted in response to a determination that the vehicle is stationary or near stationary to contro' the display apparatuses adjacent to the vehicle to each display a video.

[091091 In one embodiment the controller arrangement comprises a separate display controller associated with each display apparatus, each display apparatus includes a memory storing the frames of a video, and each display controller is adapted to select the frame to he displayed dependent upon the sensor output.

[00119] One embodiment provides a method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising detecting the vehicle passing along the path to generate sensor outputs; and controlling a plurality of two dimensional display apparatuses arranged adjacent to and along the path to output video frames to generate an apparently stationary video visible to the passenger by outputting a sequence of video frames on sequentially arranged display apparatuses along the path in dependence upon the sensor output, and, in response to a determination that the vehicle is stationary or near stationary controlling the display apparatuses adjacent to the vehicle to each display a video.

[09111] In one embodiment a separate display controller is associated with each display apparatus, each display apparatus stores the frames of a video, and each display controller selects the frame to be displayed dependent upon the sensor output.

[90112] It will be readily understood to those skilled in the art that various other changes in the details, material, and arrangements of the parts and method stages which have been described and illustrated in order to explain the nature of the inventive subject matter may he made without departing from the principles and scope of the inventive subject matter as expressed in the suhjoined claims.

Claims

CLAHYIS

-A system for displaying video fTames of a video to a passenger in a vehicle travelling along a path, the system comprising: a plurality of display apparatuses arranged adjacent to and along the path to output the video frames to be visible to the passenger; at least one sensor arrangement to detect the vehicle passing along the path to generate an output; and a controller arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output, and to control the display apparatuses to omit to display at least one frame of the video when the sensor output is indicative that the speed of the vehicle is less than a predefined speed for a period of time and/or to add or repeat at least one frame of the video when the sensor output is indicative that the speed of the vehicle is greater than the predefined speed for a period of tima
2. A system according to claim i, wherein the video has a length, and the controfler arrangement is adapted to control the display apparatuses to omit andlor to add or repeat at least one frame to disp'ay the video to the passenger to have the length.
3. A system according to claim I or claim 2, wherein the controller arrangement is adapted to control each disphiy apparatus to display a frame of the video, and to select the frame to be displayed dependent upon the sensor output.
4. A system according to any preceding claim, wherein the controller arrangement comprises a separate display controller associated with each display apparatus, each display apparatus includes a memory storing a plurality of video frames for the video, and each display controller is adapted to select the frame to he displayed dependent upon the sensor output.
5. A system according to any preceding claim, wherein the predefined speed comprises one of: an average speed of a plurafity of vehicles traveling along the path, and a maximum permitted speed of the vehicle traveling along the path.
6. A system according to any preceding claim, wherein the display apparatuses are spaced apart a distance defined by a predefined speed of the vehicle divided by a frame rate of the video to be displayed.
7. A system according to any preceding claim, wherein the controller arrangement is adapted to control each display apparatus in sequence along the path to display a sequential video frame, and to omit every n' frame when the sensor output is indicative that the speed of the vehicle is (1-1/n) times the predefined speed for a period of at least n times the frame rate, and/or add or repeat a frame every nth frame when the sensor output is indicative that the speed of the vehicle is (1+1/n) times the predefined speed for a period of at east n times the frame rate, where n >2.
8. A system according to any preceding claim, wherein, when the sensor output is indicative that the vehicle has been travelling less than the predefined speed for a period of time, the controller arrangement is adapted to control at least one said display apparatus ocated at a distal part of the path and not required to display video frames to display static images to the passenger.
9. A method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising: detecting the passing of the vehicle using at least one sensor arrangement arranged along the path to generate a sensor output; controlling a pluraUty of display apparatuses arranged adjacent to and along the path to output video frames to generate an apparenUy stationary video visible to the passenger dependent upon the sensor output; and controlling the display apparatuses to omit to disp'ay at least one frame of the video when the sensor output is indicative that the speed of the vehicle is less than a predefined speed for a period of time and/or to add or repeat at least one frame of the video when the sensor output is illdicative that the speed of the vehicle is greater than the predefined speed for a period of time.
10. A method according to claim 9, wherein the video has a length, and the display apparatuses are controlled to omit and/or to add or repeat at least one frame to display the video to the passenger to have the length.
11. A method according to claim 9 or claim 10, wherein each display apparatus is controlled to display a frame of the video, and to select the frame to be displayed dependent upon the sensor output.
12. A method according to any one of claims 9 to II, wherein the control is performed by a separate display controfler associated with each display apparatus, each display apparatus stores a plurality of video frames for the video, and each display controller selects the frame to he displayed dependent upon the sensor output.
13. A method according to any one of claims 9 to 12, wherein the predefined speed comprises one of: an average speed of a p'urality of vehicles traveling along the path, and a maximum permitted speed of the vehicle traveling along the path.
14. A method according to any one of claims 9 to 13, wherein the display apparatuses are spaced apart a distance defined by a predefined speed of the vehicle divided by a frame rate of the video to be displayed.
15. A method according to any one of claims 9 to 14, wherein each display apparatus is controlled in sequence along the path to display a sequential video frame, and to omit every n1' frame when the sensor output is indicative ftat the speed of the vehicle is (I -I/n) times the predefined speed for a period of at least n ---di-times the frame rate, and/or add or repeat a frame every n frame when the sensor output is indicative that the speed of the vehicle is (1±1/n) times the predefined speed for a period of at least n times the frame rate, where n ?2.
16. A method according to any one of claims 9 to 15, wherein, when sensor output is indicative that the the vehicle has been travelling less than the predefined speed for a period of time, at least one said display apparatus located at a distal part of the path and not required to display video frames is controlled to display static images to the passenger.
17. A system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system compnsing: a plurality of display apparatuses arranged adjacent to and along the path to generate the video frames to he visible to the passenger, at least some of said display apparatuses being arranged at irregular spacings and known positions along the path; at least one sensor arrangement to detect the vehicle passing along the path to generate an output; and a contniller arrangement adapted to control the display apparatuses to output video frames on the display apparatuses to generate an apparently stationary video visible to the passenger dependent upon the output of the at least one sensor arrangement, and to further control the timing of the output of frames by the at least some of said display apparatuses dependent upon the known positions of the at least some of said display apparatuses.
18. A system according to claim 17, wherein the controller arrangement comprises a separate display controller associated with each display apparatus, each display apparatus includes a memory storing at least one video frame for the video, and cacTi display controller is adapted to select the frame to he displayed dependent upon the output of the at east one sensor arrangement and cacTi display controller of the at least some of said display apparatuses is adapted to also select the frame dependent upon the known positions of the at least some of said display apparatuses.
19. A method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising: detecting the vehicle passing alollg the path using at least one sensor arrangement to generate an output; controlling a plurality of display apparatuses arranged adiacent to and along the path to output video frames on the display apparatuses to generate an apparently stationary video visible to the passenger dependent upon the fflutput of the at least one sensor arrangement; wherein at least some of said display apparatuses are arranged at irregular spacings and known positions along the path, and the timing of the output of frames by the at least some of said display apparatuses is controlled dependent upon the known positions of the at least some of said display apparatuses.
20. A method according to claim 19, wherein the controlling is performed by a separate display controller associated with each display apparatus, each display apparatus stores at least one video frame for the video, and each display controller selects the frame to he displayed dependent upon the output of the at east one sensor arrangement and each display controller of the at least some of said display apparatuses also selects the frame dependeilt upon the knowil positions of the at least some of said display apparatuses.
2k A system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system compnsing: a plurality of display apparatuses arranged adjacent to and along the path to output the video frames to he visible to the passenger; at least one sensor arrangement to detect the vehicle passing along the path to generate an output; and a controller arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visible to the passenger dependent upon the sensor output, to control adjacent display apparatuses in a group to each sequentially output the same video frame, and to control adiacent groups of display apparatuses to display sequential video frames.
22. A system according to claim 21, wherein the controller arrangement is adapted to group adiacent display apparatuses to adjust the number of display apparatuses in a group dependent upon the sensor output.
23. A system according to claim 2i, wherein the controller arrangement is adapted to adjust the number of display apparatuses sequentially outputting the same video frame in a group dependent upon the determined speed of the vehicle by disabling the output of at least one display apparatus in the group.
24. A system according to claim 22 or claim 23, wherein the controller arrangement is adapted to adjust the number of display apparatuses in a group to one dependent upon the sensor output.
25. A system according to any one of claim 21 to 24, wherein each display apparatus comprises a column of light sources adapted to output a columnar section of pixels in the frame, and the controller arrangement is adapted to control each display apparatus to output the columnar section of pixels multiple times to generate a frame.
26. A system according to claim 25, wherein the co'umn of light sources is adapted to output a sin&e coILImn of pix&s in tile frame.
27. A system according to any one of claims 21 to 26, wherein the controller arrangement comprises a separate display coiltroller associated with each display apparatus, each display apparatus includes a memory storing a plurality of frames for the video, and each display controller is adapted to select the frame to be displayed depeildent upon the sensor output.
28. A method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising: detecting the vehicle passing along the path to using at least one sensor arrangement to generate a sensor outputs: and controlling a plurality of display apparatuses arranged adiacent to and along the path to generate the video frames to be visible to the passenger dependent upon the sensor output, by controlling adjacent display apparatuses in a group to each sequentially output the same video frame, and controlling adjacent groups of display apparatuses to disp'ay sequential video frames.
29. A method according to claim 28, including grouping adjacent display apparatuses to adjust the number of display apparatuses in a group dependent upon the sensor oLItpLlt.
30. A method according to claim 28, including adjusting the number of display apparatuses sequentially outputting the same video frame in a group dependent upon the sensor output by disablifig the output of at least one display apparatus in the group.
3k A method according to claim 29 or claim 30, including adjusting the number of display apparatuses in a groip to one dependent ipon the sensor output.
32. A method according to any one of claims 28 to 31, wherein each display apparatus comprises a column of light sources to output a columnar section of pix&s in the frame, and each display apparatus is controlled to output the columnar section of pixels multiple times to generate a frame.
33. A method according to claim 32, wherein the column of light sources outputs a single colrnnn of pixels in the frame.
34. A method according to any one of claims 28 to 33, wherein each display apparatus is separately controlled, each display apparatus stores a plurality of frames for the video, and the frame to be displayed is selected dependent upon the sensor output.
35. A system for displaying video frames of a video to a passenger in a vehicle travelling along a path, the system compnsing: a plurality of two dimensiona' display apparatuses arranged adjacent to and along the path to output the video frames to he visible to the passenger: at least one sensor arrangement to detect the vehicle passing along the path to generate an output and a controfler arrangement adapted to control the display apparatuses to output video frames to generate an apparently stationary video visihe to the passenger by outputting a sequence of video frames on sequentially arranged display apparatuses along the path in dependence upon the sensor output, wherein the contr&ler arrangement is adapted to determine if the vehicle is stationary or near stationary and if so, to control the display apparatuses adjacent to the vehicle to each display a video.
36. A system according to claim 35, wherein the controller arrangement comprises a separate display controller associated with each display apparatus, each display apparatus includes a memory storing the frames of a video, and each display controfler is adapted to select the frame to he displayed dependent upon the sensor output.
37. A method of displaying video frames of a video to a passenger in a vehicle travelling along a path, the method comprising: detecting the vehicle passing alollg the path using at least one sensor arrangement to generate an sensor output; and controlling a plurality of two dimensional display apparatuses arranged adjacent to and along the path to output video frames to generate an apparently stationary video visible to the passenger by outputting a sequence of video frames on sequentially arranged display apparatuses along the path in dependence upon the sensor output, and, in response to a determination that the vehicle is stationary or near stationary controlling the display apparatuses adiacent to the vehicle to each display a video.
38. A method according to claim 37, wherein a separate display controller is associated with each display apparatus, each disp'ay apparatus stores the frames of a video, and each display controller selects the frame to he displayed dependent upon the sensor output.