Abstract: A billboard which is formed as a dasher board (600) and adapted for use in a video content replacement system (400) is described. The dasher board (600) comprises at least one non-visible radiation source (604) arranged to emit non-visible radiation toward a light guide plate (602). The light guide plate (602) is arranged to distribute the non-visible radiation over the light guide plate (602) and radiate the non-visible radiation away from the dasher board (600). An area of the light guide plate (602) over which non-visible light is distributed from is correlated to an area of the dasher board (600) which is to be replaced in the video content replacement system (400). There is also described is a billboard (700) similarly adapted for use in a video content replacement system (400) and which comprises an electronic display, as well as a method of retrofitting an existing billboard (10) ready for use in a video content replacement system (400).

Abstract: A subject, such as a billboard, has a filtering film to absorb electromagnetic radiation specifically in a first wavelength band. A detector provides a first detector signal relating to the first wavelength band and a second detector signal relating to another, different, second wavelength band, respectively. Suitably, the subject appears with high intensity in one band and with low intensity in the other. A content replacement unit produces a mask signal by identifying regions of contrast between the first and second detector signals as target areas. A content substitution unit selectively replaces the target areas with alternate image content to generate modified video images. The system is useful, for example, to generate multiple live television broadcasts each having differing billboard advertisements.

Abstract: A subject (10), such as a billboard, has a filtering film (15) to absorb electromagnetic radiation specifically in a first wavelength band. A detector (60) provides a first detector signal (61a) relating to the first wavelength band and a second detector signal (61b) relating to another, different, second wavelength band, respectively. Suitably, the subject (10) appears with high intensity in one band and with low intensity in the other. A content replacement unit (40) produces a mask signal (43) by identifying regions of contrast between the first and second detector signals (61a, 61b) as target areas (75). A content substitution unit (47) selectively replaces the target areas (75) with alternate image content (42) to generate modified video images (72). The system is useful, for example, to generate multiple live television broadcasts each having differing billboard advertisements.

Abstract: A sample key signal frame (602) and/or a sample image frame (601) may be stored showing a finely detailed element (101) at a first resolution (e.g. a zoomed-in image). A current image signal (71) includes the same finely-detailed element (101) at a second, lower, resolution (e.g. a wide-angle image). The sample (601, 602) is scaled and/or transformed to match a target area (10,14) within the current image (71), and may be used to perform an image enhancement process which enhances the detailed element (101) within an enhanced modified image frame (74). Thus, a more photo-realistic image is achieved.

Abstract: An original image layer is mixed with one or more graphics layers to form a composite video signal, such as in a vision mixer. Also, the same graphics layers are mixed identically into another, known background image layer to give a second composite video signal. The currently applied added graphics layers are determined, without directly accessing the added graphics layers themselves, using only the first and second composite video signals, the original image layer, and the known background image, such as in a graphics layer detection device. A triangulation matting algorithm may be used in one example.

Abstract: A method and apparatus 200 are provided for identifying image frames 10 in a video stream 20, and for comparing one video stream 20-1 against one or more other video streams 20-2. The or each video stream 20 is examined to produce a respective digest stream 320-1 comprising digest values 310-1, which may be recorded in a digest record 410. A candidate image frame 10-2 from a second video stream 20-2 provides a respective second digest value 310-2. A match of the digest values indicates matching images in the respective video streams.

Abstract: The invention allows detecting which graphics, if any, have been added to the video signal at any given time by utilizing only the various signals provided by prior art hardware. A first video signal, graphics signal(s), and a second video signal are received. It is then determined which graphics, if any, are present in a given frame of the received second video signal based on comparing actual values of pixels of the received second video signal and calculated values of pixels derived from the first video signal, and the graphics signal(s), and the combination of graphics signal(s) which produces the best match is searched for.

Abstract: The invention allows detecting which graphics, if any, have been added to the video signal at any given time by utilizing only the various signals provided by prior art hardware. A first video signal, graphics signal(s), and a second video signal are received. It is then determined which graphics, if any, are present in a given frame of the received second video signal based on comparing actual values of pixels of the received second video signal and calculated values of pixels derived from the first video signal, and the graphics signal(s), and the combination of graphics signal(s) which produces the best match is searched for.

Abstract: The invention allows detecting which graphics, if any,have been added to the video signal at any given time by utilizing only the various signals provided by prior art hardware. A first video signal, graphics signal(s), and a second video signal are received. It is then determined which graphics, if any, are present in a given frame of the received second video signal based on comparing actual values of pixels of the received second video signal and calculated values of pixels derived from the first video signal, and the graphics signal(s),and the combination of graphics signal(s)which produces the best match is searched for.

Abstract: In the method for providing an interactive television broadcast, an area of interest in a television picture, corresponding to an object of interest shown in the picture and intended to be associated with interactivity, is determined by means of a marking surface arranged in a particular location relative to the object of interest and differing from the marking surface surroundings on the basis of the radiation from it, the marking surface being detected by a detector sensitive to said radiation.

Abstract: The method for modifying the content of a target area in a television image comprises generating an original image signal (PGM1) by means of a camera, processing the original image signal by adding graphics into the television image, determining the target area in the television image, transmitting further the processed image signal (PGM2) and the target area determining data, and inserting, at a later stage of the signal transmission chain, substitutive content to the target area according to the target area determining data. According to the present invention, the graphics is added into the television image according to a predetermined graphics percentage of coverage; and to the shared area of the target area and the additional graphics area, the substitutive content is inserted according to the residual percentage of coverage not covered by the added graphics.