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Method and apparatus for determining the position of a TV camera for use in a virtual studio

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Publication number
US20010048483A1
US20010048483A1 US09921160 US92116001A US20010048483A1 US 20010048483 A1 US20010048483 A1 US 20010048483A1 US 09921160 US09921160 US 09921160 US 92116001 A US92116001 A US 92116001A US 20010048483 A1 US20010048483 A1 US 20010048483A1
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Prior art keywords
lines
edge
camera
points
horizontal
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Abandoned
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US09921160
Inventor
Alexander Steinberg
Zinovy Livshits
Itzhak Wilf
Moshe Nissim
Michael Tamir
Avi Sharir
David Aufhauser
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Orad Hi Tec Systems Ltd
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Orad Hi Tec Systems Ltd
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00Details of television systems
    • H04N5/222Studio circuitry; Studio devices; Studio equipment ; Cameras comprising an electronic image sensor, e.g. digital cameras, video cameras, TV cameras, video cameras, camcorders, webcams, camera modules for embedding in other devices, e.g. mobile phones, computers or vehicles
    • H04N5/2224Studio circuitry; Studio devices; Studio equipment ; Cameras comprising an electronic image sensor, e.g. digital cameras, video cameras, TV cameras, video cameras, camcorders, webcams, camera modules for embedding in other devices, e.g. mobile phones, computers or vehicles related to virtual studio applications
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00Details of television systems
    • H04N5/222Studio circuitry; Studio devices; Studio equipment ; Cameras comprising an electronic image sensor, e.g. digital cameras, video cameras, TV cameras, video cameras, camcorders, webcams, camera modules for embedding in other devices, e.g. mobile phones, computers or vehicles
    • H04N5/262Studio circuits, e.g. for mixing, switching-over, change of character of image, other special effects ; Cameras specially adapted for the electronic generation of special effects
    • H04N5/272Means for inserting a foreground image in a background image, i.e. inlay, outlay
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N9/00Details of colour television systems
    • H04N9/64Circuits for processing colour signals
    • H04N9/74Circuits for processing colour signals for obtaining special effects
    • H04N9/75Chroma key

Abstract

A method of determining the position of a TV camera relative to a patterned panel being viewed by the TV camera including the steps of:
identifying a plurality of edge points of the pattern from the video signal produced by said camera and using these edge points to calculate the perspective of the pattern relative to the camera.

Description

  • [0001]
    The present invention relates to methods and apparatus for creating virtual images and for determining the relative position of a TV camera.
  • [0002]
    Chroma Key panels are known for use in TV studios. By focusing a TV camera onto a chroma-key background (or panel) and positioning a foreground object in front of the panel a combined picture can be created in which the foreground object appears against a virtual background which can be, for example, a still picture or a video sequence.
  • [0003]
    A problem which arises from this basic technique is that the camera cannot be allowed to move because the virtual background and the foreground object (possibly a TV presenter) will not move synchronously as in real life.
  • [0004]
    In JP 57-93788 a chroma-key panel is used which includes a series of equidistant parallel lines, FIG. 11, of two different shades of backing colour to monitor any changes in zoom which are manifested as changes in the frequency of the video signal. The boundaries of a chroma-key window are detected in order to fit the inserted image in size and position to the chroma-key window.
  • [0005]
    Perspective can be solved by using a two shade pattern with characteristic features etc. Such features may include characters, symbols, vertices of polygons etc. Whenever at least the image features can be matched with the physical pattern the perspective can be solved.
  • [0006]
    For the purpose of the present invention, the description will generally be confined to the use of a TV camera within a virtual studio but it is to be understood that the invention can be used for general tracking of a TV camera or an object on which it is positioned.
  • [0007]
    In co-pending Israeli Patent Application No. 109,487 to the same applicant, the use of chroma-key patterned panels is disclosed. These panels have a defined pattern which allows the video signals generated by the TV camera to be processed to ascertain the position of the camera.
  • [0008]
    A problem which arises in the above prior art systems is that for large zoom in factors the features in the Field of View (FOV) are reduced in number. Also, for a substantial occlusion the recognition of robust features may be difficult. Since the present invention movement and zoom of the camera are permitted and also the foreground object is allowed to move, these circumstances are very likely to occur.
  • [0009]
    In addition large perspective distortion makes the recognition of features very difficult in particular when said features comprise characters, graphical symbols etc.
  • [0010]
    If the camera loses synchronism between the foreground real object and the virtual background then the effect will be a loss of reality in the composite picture. Thus, as explained above, early previous systems were limited to a static camera and the later systems, although allowing camera movement, may still be subjected to a loss of synchronism between foreground and background.
  • [0011]
    Obviously if none of the patterned chroma-key background is visible then synchronism cannot be maintained but also is not necessary since no virtual background will be shown.
  • [0012]
    As the camera zooms in to the foreground object, the background chroma-key panel will become more occluded by the foreground object and the characteristic pattern will be broken and/or distorted in the case of large perspective views.
  • [0013]
    It is an object of the present invention to provide a TV camera position determination apparatus and method for measuring the position of a TV camera relative to a panel when part of the panel is occluded by a foreground object.
  • [0014]
    It is also an object of the present invention to provide a virtual studio system in which the TV camera is able to be moved laterally with respect to a foreground object and to a background chroma-key panel; in which the camera is able to zoom in and out with respect to the foreground object without losing synchronism between the foreground object and the virtual background even when the chroma-key panel is substantially completely occluded by the foreground object.
  • [0015]
    It is also a further object of the present invention to provide a camera positioning apparatus in which the position of a TV camera relative to a patterned panel can be determined even when a substantial part of the panel is obscured by an occluding object.
  • [0016]
    The present invention therefore provides a method of determining the position of a TV camera relative to a patterned panel being viewed by the TV camera including the steps of identifying a plurality of edge points of the pattern from the video signal produced by said camera and using these edge points to calculate the perspective of the pattern relative to the camera.
  • [0017]
    Preferably the method comprises the steps of identifying a plurality of said first edge points and a plurality of said second points; and producing an edge image.
  • [0018]
    Preferably two or more families of edges are used such that the edges of each family lie on a set of parallel lines comprising at least two lines. Preferably the orientations of the families are sufficiently far apart such that an edge point can be assigned to a specific family by means of its orientation only.
  • [0019]
    In a specific embodiment said patterned panel comprises a pattern of vertical and horizontal straight edges defining lines delineating a colour difference and in which each edge point is situated on one of said horizontal or vertical straight lines.
  • [0020]
    In a first embodiment said plurality of first edge points are clustered to associate edge points to specific lines using a slope and intercept process.
  • [0021]
    In a second embodiment steps of processing the video signal relating to said first and said second plurality of edge points comprise the steps of analysing all detected edge points and grouping together edge point into a first plurality of groups corresponding to horizontal lines and a second plurality of group corresponding to vertical lines.
  • [0022]
    Preferably the edge points in the first and second plurality of groups are allocated preliminarily to specific horizontal and vertical lines.
  • [0023]
    Preferably the step of allocation is followed by computation of the vanishing points of the horizontal and vertical lines, said vanishing points being computed within a defined location error.
  • [0024]
    The perspective projection of any set of parallel lines which are not parallel to the image plane, will converge to a vanishing point. In the singular case where the lines are parallel to the image plane, the vanishing point is at infinity.
  • [0025]
    Preferably the method also includes the step of projecting the edges corresponding to horizontal edges to obtain an edge projection profile map comprising peaks and troughs.
  • [0026]
    Preferably in the projection process a vertical accumulator array H[y] is cleared to zero. Then for each horizontal edge, the line connecting the vanishing point (previously computed for horizontal edges) with the edge is computed. That line is then intersected with the vertical axis (x=0). The cell of the accumulator array which corresponds to the intersection point is then incremented. Peaks in that array correspond to candidate lines.
  • [0027]
    Preferably the method further includes the step of assigning each horizontal edge to a most probable peak and producing a list of edges for each of a plurality of candidate lines indicated by the peak.
  • [0028]
    Preferably a line is specified for each list of edges, edges not corresponding to any specified line being disregarded.
  • [0029]
    The method steps are then preferably repeated for vertical edges and lines.
  • [0030]
    In the method an accurate video image edge line pattern is produced and in which the known pattern on the panel is compared with the edge line pattern.
  • [0031]
    This comparison preferably comprises a first step of identifying a first horizontal line in the accurate video image edge pattern, identifying a second horizontal line in the accurate video image pattern, calculating the distance between said first and second video image lines, comparing the calculated distance between the video image lines with the known pattern to produce a horizontal position and scale determination, repeating said steps to produce a vertical position and scale determination and from said horizontal and vertical position and scale determinations.
  • [0032]
    Once all positions and scales have been determined, the matching between the pattern and the image is now complete. Preferably, that matching is used to solve for the final, accurate perspective transformation between the pattern and the image.
  • [0033]
    Preferably, the perspective transformation is used to solve for the position of the TV camera relative to the panel.
  • [0034]
    Preferably the patterned panel comprises a chroma-key panel having two separately identifiable chroma-key colours. Preferably the patterned panel comprises two or more distance coded families of lines.
  • [0035]
    In a further preferred embodiment the patterned panel comprises two or more families of lines such that the lines of each family intersect at a common point.
  • [0036]
    The present invention also provides apparatus for determining the position of a TV camera relative to a patterned panel being viewed by the TV camera including:
  • [0037]
    means for identifying a plurality of edge points 6 f the pattern from the vedeo signal produced by said camera and means for processing these edge points to calculate the perspective of the pattern relative to the camera.
  • [0038]
    Embodiments of the present invention will now be described, by way of example with reference to the accompanying drawings in which:
  • [0039]
    [0039]FIG. 1 shows a patterned panel for use in the present invention;
  • [0040]
    [0040]FIG. 2 shows a close up of a, portion of the panel of FIG. 1 with an occluding object obscuring part of the pattern;
  • [0041]
    [0041]FIG. 3 shows a perspective view of FIG. 2 from one side;
  • [0042]
    [0042]FIG. 4 shows a complex perspective view from one side and above;
  • [0043]
    [0043]FIG. 5 illustrates the process for identification of edge points;
  • [0044]
    [0044]FIG. 6 illustrates diagrammatically the initial vanishing point calculation for the edge points;
  • [0045]
    [0045]FIG. 7 illustrates diagrammatically the rectified line image;
  • [0046]
    [0046]FIG. 8 illustrates the projected line images for the horizontal lines;
  • [0047]
    [0047]FIG. 9 shows the accurate video lines after final processing for comparison with the pattern of FIG. 1;
  • [0048]
    [0048]FIG. 10 illustrates the inventive concept of using coded bundles of lines;
  • [0049]
    [0049]FIG. 11 shows the top level flow of processing, and FIG. 12 illustrates the line detection process.
  • [0050]
    With reference now to the drawings, FIG. 1 shows a patterned panel 10 which comprises a plurality of vertical and horizontal lines 12, 14. These lines may be formed from narrow line or stripes of different colour, their function being to provide a plurality of defined edges.
  • [0051]
    For chroma-key panels the colours of the lines or stripes will preferably be different shades of the same colour.
  • [0052]
    The lines need not be horizontal or vertical but will preferably always be parallel straight lines with a predetermined angular relationship between the generally horizontal and vertical lines. Preferably in any pattern two or more families of edges are provided such that the edges of each family lie on a set of parallel lines comprising at least two lines. Also preferably the orientations of the families are far apart such that an edge point can be assigned to a specific family by means of its orientation only.
  • [0053]
    The TV camera 20 indicated diagrammatically is shown in FIG. 1 viewing the panel directly from the front.
  • [0054]
    In FIG. 2 the video image viewed by camera 20 is shown. The TV camera 20 is operated to zoom in to the area 10′ shown dotted in FIG. 1 and an occluding object 30 of irregular shape is shown occluding part of the pattern. The pattern in FIG. 2 is therefore not continuous and it may be seen that there are no continuous horizontal lines in the zoomed video image.
  • [0055]
    In FIG. 2 only one occluding object is shown but there may be several producing further discontinuities in the lines.
  • [0056]
    In FIG. 3 the camera has been moved to create a simple perspective which illustrates that the generally horizontal lines 14 are not now parallel and in FIG. 4 in the more complex perspective, neither the horizontal or vertical lines are parallel.
  • [0057]
    With the change in size of the pattern, discontinuities in the lines and the non-parallel image matching the video image pattern in FIG. 4 with a pattern of the panel stored in digital format will be extremely difficult since no part of the video image corresponds to the stored pattern.
  • [0058]
    The method of the present invention provides a means for determining the position of the TV camera from the video image of FIG. 4.
  • [0059]
    Preferably in the pattern of FIG. 1 the line spacings are not all equal such that distance ratios in sets of adjacent lines are unique within the family of either horizontal or vertical lines. Thus if it is possible to identify the line spacing between two vertical lines 121, 122 and two horizontal lines 141, 142 then the area of the pattern forming part of the video image can be identified.
  • [0060]
    However, because of the unknown magnification or zoom of the TV camera, the unknown complex perspective and occlusion the lines appear totally different from the pattern in FIG. 1.
  • [0061]
    The method comprises identifying a large plurality of edge points 144 as shown in FIG. 4. Each edge point may be considered to comprise a mini-line having slope and intercept as indicated by angle 148. It may also have a nominal direction if it is on a line of any thickness as indicated by arrow 146. The locations of these edge points are stored digitally to provide an initial edge point map. As can be seen in FIG. 4 there may be substantial blank areas in the centre portion where the occlusion occurs but within this area there may be false edge points not correctly belonging to the pattern which will be recorded and will require to be discarded.
  • [0062]
    The edge points are allocated in groups to specific lines in the horizontal and vertical directions using the Hough transform [J. Illingworth and J. Kittler, A survey of the Hough transform, Computer Vision, Graphics and Image Processing, 26, pp. 139-161 (1986)].
  • [0063]
    Alternatively the initial parallelism of line sets is used to provide approximate positions of line sets in the horizontal and vertical directions.
  • [0064]
    It may be seen from FIG. 4 that none of the lines are either horizontal or vertical due to the perspective change. These terms are therefore used herein generally to refer to lines which are substantially horizontal or vertical, that is to say nearer to the horizontal rather than to the vertical and vice versa.
  • [0065]
    With reference now to FIG. 5 each line, as approximately determined by either grouping of the edge point and/or by computation of the initial parallelism of the line sets is projected to an approximate vanishing point for both horizontal (150) and vertical lines (152). As shown the lines will not intersect at a single point because the of the errors and thus a “circle” of error 150, 152 is allowed, the centre of the circle, for example, being considered to be the vanishing point. When the camera is looking perpendicular to the panel, the vanishing point is at infinity. Working in a homogeneous coordinate system, the latter case can be handled as well.
  • [0066]
    With reference to FIG. 7, the horizontal vanishing point is used to cluster the horizontal edge points into lines. The line connecting the vanishing point Ph with edge point E1 is intersected with the vertical axis. The process is repeated for all horizontal edge points. Clearly, for real lines which are characterised by a multitude of edge points, the intersection points will tend to accumulate as shown in FIG. 7. False edges or very short visible lines will contribute mode randomly. In FIG. 8, the intersections provide a histogram type waveform. The process is described for horizontal lines but will be repeated for the vertical lines.
  • [0067]
    Each edge point is reassessed by assigning it to the most probable peak and a revised list of edges is then stored for each probable candidate such as 160, 161, 162 in FIG. 8.
  • [0068]
    Those edge points which are found not to correspond to a probable candidate are discarded. thus, for horizontal lines, a list of edge points has now been produced which will accurately align with the horizontal lines 141, 142, line 141 being, for example, aligned with peak 161 and line 142 with peak 162 by means of a list of edge points for each line. The lines are therefore accurately detected.
  • [0069]
    This process is then repeated for the vertical lines.
  • [0070]
    The edge points assigned to a most probable peak are processed to find a line passing through these points in some optimal sense. For example, the least-squared error line can be computed. The vanishing points can be now computed more accurately, as a most probable intersection points of a set of horizontal (or vertical lines).
  • [0071]
    Let the vanishing point of the horizontal bundle be given in homogeneous coordinates by (Xh, Yh, Wh). Also let the vanishing point of the vertical bundle (or set of lines) be given by (Xv, Yv, Wv). These points correspond to vanishing points (1, 0, 0) and (0, 1, 0) of the parallel bundles on the panel. From this correspondence, the perspective transformation can be solved up to the shift and scale determinations for both bundles. Applying the inverse transformation to the detected lines, produces an accurate grill pattern as shown in FIG. 9.
  • [0072]
    This pattern is then matched against the stored pattern (FIG. 1) for each axis independently. In the search process each line L4 may be any line in the horizontal pattern. L5 is, however, the next line and the distance or pattern being unique the lines can be identified. If we assume that no lines are missing then we have a matching solution in the horizontal direction and by a similar process we will have a matching solution in the vertical direction.
  • [0073]
    If some lines are missing then a score is determined for the number of other matching lines and a search can be conducted, using the knowledge of the matched lines, for any missing lines. If these are totally obscured then a decision can be taken on a match using a threshold value for the scores for both vertical and horizontal directions.
  • [0074]
    To obtain the exact vanishing points and perspective, the corrected list of edge points for each line is used to provide accurate line equations, thereby enabling the vanishing points to be accurately calculated.
  • [0075]
    Having matched the lines, one knows not only the perspective distortion as before but also the shifts and scales. This completes the determination of the perspective transformation and thereby the position of the TV camera relative to the panel.
  • [0076]
    The system can provide such information either in the case that one or more lines in the pattern are obscured totally or in the event that the lines are discontinuous. The system can, therefore, work with high camera zoom parameters where only a very small fraction of the panel is visible.
  • [0077]
    With reference now to FIG. 10, the concept of a parallel family of lines can be extended to an intersecting family using an alternative system of coded bundles 200 (FIG. 10a) (families of lines). The lines are not parallel, yet one can use basically the same techniques.
  • [0078]
    Consider two parallel coded bundles 202′, 204′ (“primary bundles”) which is transformed by a known perspective transformation (the “pretransformation”) in the panel design process to 2 intersecting bundles (“pattern bundles”). These bundles are further transformed by the (unknown) camera perspective transformation and appear as “image bundles” 202″, 204″ (FIG. 10c).
  • [0079]
    Clearly, the combination of the pre-transformation and the camera transformation is an unknown perspective transformation. We proceed as in the usual algorithm to find that unknown transformation (between the primary bundles FIG. 10a and the image bundles FIG. 10c). Once that transformation is known, we use the pre-transformation to extract the camera transformation (between the pattern bundles and the image bundles).
  • [0080]
    [0080]FIG. 11 shows the top level flow of the processing, staring from a video signal 1100 and producing an estimate of the perspective transformation 1102 from the panel to the image. To reduce the number of false edges due to foreground objects, a chroma-keyer 1104 is used to segment the background (which contains the pattern information) from the foreground. This segmentation is performed based on a key signal which describes the distance of a specific pixel from the backing colour (preferably blue or green). To further reduce the number of false edges the key image is preferably filtered 1106 to remove isolated features and pixels near the border of foreground objects. This filtering is preferably done using morphological image processing [Serra, J. Image Analysis and Mathematical Morphology, Academic Press, London 1982].
  • [0081]
    Edge detection is then applied 1108 to the background image. The method is not sensitive to the specific edge detector used. For a survey see [A. Rosenfeld and A, Kak, Digital Picture Processing, Academic Press 1982, Vol. 2, pp. 84-112].
  • [0082]
    Preferably the edge detection process consists of the following steps:
  • [0083]
    1. Smoothing the image to reduce the effect of image noise.
  • [0084]
    2. Computing a gradient vector (magnitude and directions) at each pixel, by means of x and y spatial derivatives.
  • [0085]
    3. Thresholding the gradient magnitude and suppressing pixels where the gradient response does not have a local maximum. This suppression step is necessary to obtain thin edge contours.
  • [0086]
    4. Storing the edge points in an edge array.
  • [0087]
    The line detection process is further described with reference to FIG. 12 for horizontal lines. Vertical lines are processed in a similar manner.
  • [0088]
    From a list of horizontal edge points an approximate vanishing point is computed 1202. Each edge is projected through a vanishing point 1204 to produce a projection histogram which is analysed 1206, to find the peaks. The list of peaks is compared with each edge point to assign an edge point to a peak and to then fit the lines 1208 to provide a list of lines.

Claims (24)

1. A method of determining the position of a TV camera relative to a patterned panel being viewed by the TV camera including the steps of:
identifying a plurality of edge points of the pattern from the video signal produced by said camera and using these edge points to calculate the perspective of the pattern relative to the camera.
2. A method as claimed in
claim 1
comprising the steps of:
identifying a plurality of first edge points and a plurality of second edge points; and
producing an edge image.
3. A method as claimed in
claim 2
in which said patterned panel comprises a pattern of vertical and horizontal straight edges defining lines delineating a colour difference and in which each edge point is situated on one of said horizontal or vertical straight lines.
4. A method as claimed in
claim 3
in which said plurality of first edge points are clustered to associate edge points to specific lines using a slope and intercept process.
5. A method as claimed in
claim 3
in which said steps of processing the video signal relating to said first and said second plurality of edge points comprises the steps of:
analysing all detected edge points and grouping together edge points into a first plurality of groups corresponding to horizontal lines and a second plurality of groups corresponding to vertical lines.
6. A method as claimed in
claim 5
in which the edge points in the first and second plurality of groups are allocated preliminarily to specific horizontal and vertical lines.
7. A method as claimed in
claim 6
in which the step of allocation is followed by computation of the vanishing points of the horizontal and vertical lines, said vanishing points being computed within a defined location error.
8. A method as claimed in
claim 7
further including the step of:
projecting the edges corresponding to horizontal edges to obtain an edge projection profile map comprising peaks and troughs.
9. A method as claimed in
claim 8
further including the step of:
assigning each horizontal edge to a most probable peak and producing a list of edges for each of a plurality of candidate lines indicated by the peak.
10. A method as claimed in
claim 9
in which a line is specified for each list of edges, edges not corresponding to any specified line being disregarded.
11. A method as claimed in
claim 10
in which the steps are repeated for vertical edges and lines.
12. A method as claimed in
claim 11
in which accurate vanishing points are computed from the specified lines.
13. A method as claimed in
claim 11
in which the perspective transformation is solved up to the shift and scale determinations for both families of lines.
14. A method as claimed in
claim 13
in which an accurate line pattern is produced by means of inverse perspective transformation and in which the known pattern on the panel is compared with the edge line pattern.
15. A method as claimed in
claim 14
in which said comparison comprises a first step of identifying a first horizontal line in the accurate video image edge pattern, identifying a second horizontal line in the accurate video image pattern, calculating the distance between said first and second video image lines, comparing the calculated distance between the video image lines with the known pattern to produce a horizontal position and scale determination, repeating said steps to produce a vertical position and scale determination and from said horizontal and vertical position and scale determinations determining the position of the TV camera relative to the panel.
16. A method as claimed in any one of
claims 1
to
15
in which the patterned panel comprises a chroma-key panel having two separately identifiable chroma-key colours.
17. A method as claimed in any one of
claims 1
to
15
in which the patterned panel comprises two or more distance coded families of lines.
18. A method as claimed in any one of
claims 1
to
15
in which the patterned panel comprises two or more families of lines such that the lines of each family intersect at a common point.
19. A method as claimed in
claim 16
in which the determination of the position of the TV camera relative to the panel is used to calculate the perspective of a background video picture relative to a foreground object.
20. Apparatus for determining the position of a TV camera relative to a patterned panel being viewed by the TV camera including:
means for identifying a plurality of edge points of the pattern from the video signal produced by said camera and means for processing these edge points to calculate the perspective of the pattern relative to the camera.
21. Apparatus as claimed in
claim 18
in which the patterned panel is a chroma-key panel.
22. Apparatus as claimed in
claim 19
further including further processing means for processing said calculated position of the camera, background scene storage means for storage of background scene, perspective displacement means to adjust the perspective of a background scene in accordance with the calculated camera position and video display means for displaying the background scene in a correct perspective on said chroma-key background panel with foreground objects interposed between said camera and said background panel.
23. Apparatus as claimed in any one of
claims 20
to
22
in which the patterned panel comprises two or more distance coded families of lines.
24. Apparatus as claimed in any one of
claims 20
to
22
in which the patterned panel comprises two or more families of lines such that the lines of each family intersect at a common point.
US09921160 1995-09-08 2001-08-02 Method and apparatus for determining the position of a TV camera for use in a virtual studio Abandoned US20010048483A1 (en)

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CN (1) CN1104816C (en)
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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020030692A1 (en) * 2000-09-08 2002-03-14 Arnfried Griesert Method for generating a picture in a virtual studio
US6856935B1 (en) * 1998-02-18 2005-02-15 Gmd-Forschungszentrum Informationstechnik Gmbh Camera tracking system for a virtual television or video studio
US6965397B1 (en) 1999-11-22 2005-11-15 Sportvision, Inc. Measuring camera attitude
EP1628259A1 (en) * 2004-08-19 2006-02-22 Seiko Epson Corporation Automatic keystone distortion correction using a part of edges of a screen
US20080130971A1 (en) * 2006-11-30 2008-06-05 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of dna molecules
US20080226171A1 (en) * 2007-03-16 2008-09-18 Fujitsu Limited Correcting device and method for perspective transformed document images
US7720276B1 (en) * 1998-06-26 2010-05-18 Korobkin Carl P Photogrammetry engine for model construction
US7974714B2 (en) 1999-10-05 2011-07-05 Steven Mark Hoffberg Intelligent electronic appliance system and method
US8046313B2 (en) 1991-12-23 2011-10-25 Hoffberg Steven M Ergonomic man-machine interface incorporating adaptive pattern recognition based control system
US20120069177A1 (en) * 2010-09-16 2012-03-22 Seiko Epson Corporation Projector and control method for projector
US20170024861A1 (en) * 2014-04-24 2017-01-26 Panasonic Intellectual Property Management Co., Lt Vehicle-mounted display device, method for controlling vehicle-mounted display device, and non-transitory computer readable medium recording program
USRE46310E1 (en) 1991-12-23 2017-02-14 Blanding Hovenweep, Llc Ergonomic man-machine interface incorporating adaptive pattern recognition based control system

Families Citing this family (32)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2312125B (en) * 1996-04-11 1998-07-01 Discreet Logic Inc Processing image data
GB9607541D0 (en) * 1996-04-11 1996-06-12 Discreet Logic Inc Processing image data
EP0867839A3 (en) * 1997-03-27 1999-05-19 RT-Set Ltd. Method for compositing an image of a real object with a virtual scene
GB9706706D0 (en) * 1997-04-02 1997-05-21 Orad Hi Tec Systems Ltd Virtual camera control system
US5930740A (en) * 1997-04-04 1999-07-27 Evans & Sutherland Computer Corporation Camera/lens calibration apparatus and method
DE69829177T2 (en) 1997-05-06 2006-04-13 Zetex As An image processing method
DE69831181D1 (en) * 1997-05-30 2005-09-15 British Broadcasting Corp location
GB9719379D0 (en) * 1997-09-12 1997-11-12 Orad Hi Tec Systems Ltd Virtual studio position sensing system
RU2161871C2 (en) * 1998-03-20 2001-01-10 Латыпов Нурахмед Нурисламович Method and device for producing video programs
US6038889A (en) * 1999-04-14 2000-03-21 Libbey Glass Inc. Cooling system for a glassware machine
GB9928525D0 (en) * 1999-12-02 2000-02-02 Sony Uk Ltd Video signal processing
US6778699B1 (en) * 2000-03-27 2004-08-17 Eastman Kodak Company Method of determining vanishing point location from an image
WO2003005303A3 (en) * 2001-07-02 2003-09-25 Matchlight Software Inc System and method for discovering and categorizing attributes of a digital image
US6873732B2 (en) 2001-07-09 2005-03-29 Xerox Corporation Method and apparatus for resolving perspective distortion in a document image and for calculating line sums in images
DE10139846C1 (en) * 2001-08-14 2003-02-06 Daimler Chrysler Ag Method for estimating positions and locations uses alignment of image data for a camera of model structures in order to increase long-duration stability and autonomics of aerodynamic vehicles/missiles.
ES2256768T3 (en) * 2002-03-22 2006-07-16 British Telecommunications Public Limited Company Comparing models.
EP1488413B1 (en) * 2002-03-22 2012-02-29 BRITISH TELECOMMUNICATIONS public limited company Anomaly recognition method for data streams
GB0229625D0 (en) * 2002-12-19 2003-01-22 British Telecomm Searching images
JP4508553B2 (en) * 2003-06-02 2010-07-21 カシオ計算機株式会社 Correction method of the photographed image projection device, and the captured image
US7116342B2 (en) * 2003-07-03 2006-10-03 Sportsmedia Technology Corporation System and method for inserting content into an image sequence
JP2005122323A (en) 2003-10-14 2005-05-12 Casio Comput Co Ltd Photographing apparatus, image processor, and image processing method and program for photographing device
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GB0328326D0 (en) 2003-12-05 2004-01-07 British Telecomm Image processing
EP1789910B1 (en) 2004-09-17 2008-08-13 British Telecommunications Public Limited Company Analysis of patterns
EP1732030A1 (en) * 2005-06-10 2006-12-13 BRITISH TELECOMMUNICATIONS public limited company Comparison of patterns
US8135210B2 (en) * 2005-07-28 2012-03-13 British Telecommunications Public Limited Company Image analysis relating to extracting three dimensional information from a two dimensional image
CN100553348C (en) 2005-10-13 2009-10-21 致茂电子股份有限公司 Flat resolution correcting method for image optical system and apparatus thereof
EP1798961A1 (en) * 2005-12-19 2007-06-20 BRITISH TELECOMMUNICATIONS public limited company Method for focus control
US20080195938A1 (en) * 2006-12-14 2008-08-14 Steven Tischer Media Content Alteration
GB0821832D0 (en) * 2008-11-28 2009-01-07 Sony Corp Image processing system
US9215383B2 (en) 2011-08-05 2015-12-15 Sportsvision, Inc. System for enhancing video from a mobile camera
EP3104330A1 (en) 2015-06-09 2016-12-14 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Methods for tracking at least one object and method for replacing at least one object with a virtual object in a motion picture signal recorded by a camera

Citations (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2974190A (en) * 1957-12-09 1961-03-07 Columbia Broadcasting Syst Inc Electronic matting apparatus
US3848082A (en) * 1973-01-16 1974-11-12 Atlantic Res Corp System for transmitting and utilizing supplemental data via television systems
US3887762A (en) * 1972-07-28 1975-06-03 Hitachi Ltd Inspection equipment for detecting and extracting small portion included in pattern
US3973239A (en) * 1973-10-17 1976-08-03 Hitachi, Ltd. Pattern preliminary processing system
US4000399A (en) * 1973-12-28 1976-12-28 Nippon Kogaku K.K. Pattern counting system using line scanning
US4010446A (en) * 1973-07-02 1977-03-01 Kabushiki Kaisha Ricoh Character pattern line thickness regularizing device
US4200890A (en) * 1977-07-11 1980-04-29 Nippon Electric Company, Ltd. Digital video effects system employing a chroma-key tracking technique
US4393394A (en) * 1981-08-17 1983-07-12 Mccoy Reginald F H Television image positioning and combining system
US4394680A (en) * 1980-04-01 1983-07-19 Matsushita Electric Industrial Co., Ltd. Color television signal processing apparatus
US4396939A (en) * 1980-06-09 1983-08-02 Nippon Electric Co., Ltd. Chromakey effect apparatus
US4409418A (en) * 1982-07-07 1983-10-11 Phillips Petroleum Company Isomerization process
US4409611A (en) * 1981-09-24 1983-10-11 Vlahos-Gottschalk Research Corp., (Now) Ultimatte Corp. Encoded signal color image compositing
US4488169A (en) * 1981-07-09 1984-12-11 Sony Corporation Digital chromakey apparatus
US4533937A (en) * 1981-09-12 1985-08-06 Sony Corporation Key signal generating apparatus for digital chromakey system
US4547897A (en) * 1983-02-01 1985-10-15 Honeywell Inc. Image processing for part inspection
US4566126A (en) * 1982-04-30 1986-01-21 Fuji Electric Company, Ltd. Pattern discriminator
US4621280A (en) * 1984-03-15 1986-11-04 Kabushiki Kaisha Toshiba Digital chromakey apparatus
US4628280A (en) * 1984-08-20 1986-12-09 U.S. Philips Corporation Amplifier arrangement
US4628363A (en) * 1982-11-19 1986-12-09 Nec Corporation Chroma-key tracking apparatus
US4630101A (en) * 1982-10-18 1986-12-16 Nec Corporation Chromakey signal producing apparatus
US4947240A (en) * 1988-03-26 1990-08-07 Robert Bosch Gmbh Method and circuit apparatus for combining two television signals
US4949165A (en) * 1987-02-12 1990-08-14 Bts Broadcast Television Systems Gmbh Method and apparatus for testing and checking the criteria of a key signal decoder from a chromakey mixer
US4979021A (en) * 1989-11-30 1990-12-18 Thomas Milton L Optical chromakey field
US5264933A (en) * 1991-07-19 1993-11-23 Princeton Electronic Billboard, Inc. Television displays having selected inserted indicia
US5353392A (en) * 1990-04-11 1994-10-04 Multi Media Techniques Method and device for modifying a zone in successive images
US5436672A (en) * 1994-05-27 1995-07-25 Symah Vision Video processing system for modifying a zone in successive images
US5488675A (en) * 1994-03-31 1996-01-30 David Sarnoff Research Center, Inc. Stabilizing estimate of location of target region inferred from tracked multiple landmark regions of a video image
US5491517A (en) * 1994-03-14 1996-02-13 Scitex America Corporation System for implanting an image into a video stream
US5502482A (en) * 1992-08-12 1996-03-26 British Broadcasting Corporation Derivation of studio camera position and motion from the camera image
US5566251A (en) * 1991-09-18 1996-10-15 David Sarnoff Research Center, Inc Video merging employing pattern-key insertion
US5638116A (en) * 1993-09-08 1997-06-10 Sumitomo Electric Industries, Ltd. Object recognition apparatus and method
US5892554A (en) * 1995-11-28 1999-04-06 Princeton Video Image, Inc. System and method for inserting static and dynamic images into a live video broadcast
US5917553A (en) * 1996-10-22 1999-06-29 Fox Sports Productions Inc. Method and apparatus for enhancing the broadcast of a live event
US5930740A (en) * 1997-04-04 1999-07-27 Evans & Sutherland Computer Corporation Camera/lens calibration apparatus and method
US6122014A (en) * 1998-09-17 2000-09-19 Motorola, Inc. Modified chroma keyed technique for simple shape coding for digital video

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2013448B (en) * 1978-01-30 1983-02-23 Quantel Ltd Measurement of chroma key area in television systems
JPH037195B2 (en) * 1980-12-03 1991-01-31 Japan Broadcasting Corp
GB8826880D0 (en) * 1988-11-17 1988-12-21 Dickson J W Vehicle control
US6122013A (en) * 1994-04-29 2000-09-19 Orad, Inc. Chromakeying system
GB9601101D0 (en) 1995-09-08 1996-03-20 Orad Hi Tech Systems Limited Method and apparatus for automatic electronic replacement of billboards in a video image

Patent Citations (36)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2974190A (en) * 1957-12-09 1961-03-07 Columbia Broadcasting Syst Inc Electronic matting apparatus
US3887762A (en) * 1972-07-28 1975-06-03 Hitachi Ltd Inspection equipment for detecting and extracting small portion included in pattern
US3848082A (en) * 1973-01-16 1974-11-12 Atlantic Res Corp System for transmitting and utilizing supplemental data via television systems
US4010446A (en) * 1973-07-02 1977-03-01 Kabushiki Kaisha Ricoh Character pattern line thickness regularizing device
US3973239A (en) * 1973-10-17 1976-08-03 Hitachi, Ltd. Pattern preliminary processing system
US4000399A (en) * 1973-12-28 1976-12-28 Nippon Kogaku K.K. Pattern counting system using line scanning
US4200890A (en) * 1977-07-11 1980-04-29 Nippon Electric Company, Ltd. Digital video effects system employing a chroma-key tracking technique
US4409618A (en) * 1977-07-11 1983-10-11 Nippon Electric Co., Ltd. Digital video effects system employing a chroma-key tracking technique
US4394680A (en) * 1980-04-01 1983-07-19 Matsushita Electric Industrial Co., Ltd. Color television signal processing apparatus
US4396939A (en) * 1980-06-09 1983-08-02 Nippon Electric Co., Ltd. Chromakey effect apparatus
US4488169A (en) * 1981-07-09 1984-12-11 Sony Corporation Digital chromakey apparatus
US4393394A (en) * 1981-08-17 1983-07-12 Mccoy Reginald F H Television image positioning and combining system
US4533937A (en) * 1981-09-12 1985-08-06 Sony Corporation Key signal generating apparatus for digital chromakey system
US4409611A (en) * 1981-09-24 1983-10-11 Vlahos-Gottschalk Research Corp., (Now) Ultimatte Corp. Encoded signal color image compositing
US4566126A (en) * 1982-04-30 1986-01-21 Fuji Electric Company, Ltd. Pattern discriminator
US4409418A (en) * 1982-07-07 1983-10-11 Phillips Petroleum Company Isomerization process
US4630101A (en) * 1982-10-18 1986-12-16 Nec Corporation Chromakey signal producing apparatus
US4628363A (en) * 1982-11-19 1986-12-09 Nec Corporation Chroma-key tracking apparatus
US4547897A (en) * 1983-02-01 1985-10-15 Honeywell Inc. Image processing for part inspection
US4621280A (en) * 1984-03-15 1986-11-04 Kabushiki Kaisha Toshiba Digital chromakey apparatus
US4628280A (en) * 1984-08-20 1986-12-09 U.S. Philips Corporation Amplifier arrangement
US4949165A (en) * 1987-02-12 1990-08-14 Bts Broadcast Television Systems Gmbh Method and apparatus for testing and checking the criteria of a key signal decoder from a chromakey mixer
US4947240A (en) * 1988-03-26 1990-08-07 Robert Bosch Gmbh Method and circuit apparatus for combining two television signals
US4979021A (en) * 1989-11-30 1990-12-18 Thomas Milton L Optical chromakey field
US5353392A (en) * 1990-04-11 1994-10-04 Multi Media Techniques Method and device for modifying a zone in successive images
US5264933A (en) * 1991-07-19 1993-11-23 Princeton Electronic Billboard, Inc. Television displays having selected inserted indicia
US5566251A (en) * 1991-09-18 1996-10-15 David Sarnoff Research Center, Inc Video merging employing pattern-key insertion
US5502482A (en) * 1992-08-12 1996-03-26 British Broadcasting Corporation Derivation of studio camera position and motion from the camera image
US5638116A (en) * 1993-09-08 1997-06-10 Sumitomo Electric Industries, Ltd. Object recognition apparatus and method
US5491517A (en) * 1994-03-14 1996-02-13 Scitex America Corporation System for implanting an image into a video stream
US5488675A (en) * 1994-03-31 1996-01-30 David Sarnoff Research Center, Inc. Stabilizing estimate of location of target region inferred from tracked multiple landmark regions of a video image
US5436672A (en) * 1994-05-27 1995-07-25 Symah Vision Video processing system for modifying a zone in successive images
US5892554A (en) * 1995-11-28 1999-04-06 Princeton Video Image, Inc. System and method for inserting static and dynamic images into a live video broadcast
US5917553A (en) * 1996-10-22 1999-06-29 Fox Sports Productions Inc. Method and apparatus for enhancing the broadcast of a live event
US5930740A (en) * 1997-04-04 1999-07-27 Evans & Sutherland Computer Corporation Camera/lens calibration apparatus and method
US6122014A (en) * 1998-09-17 2000-09-19 Motorola, Inc. Modified chroma keyed technique for simple shape coding for digital video

Cited By (26)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
USRE46310E1 (en) 1991-12-23 2017-02-14 Blanding Hovenweep, Llc Ergonomic man-machine interface incorporating adaptive pattern recognition based control system
US8046313B2 (en) 1991-12-23 2011-10-25 Hoffberg Steven M Ergonomic man-machine interface incorporating adaptive pattern recognition based control system
US6856935B1 (en) * 1998-02-18 2005-02-15 Gmd-Forschungszentrum Informationstechnik Gmbh Camera tracking system for a virtual television or video studio
US7720276B1 (en) * 1998-06-26 2010-05-18 Korobkin Carl P Photogrammetry engine for model construction
US8542911B1 (en) 1998-06-26 2013-09-24 Carl Phillip Korobkin Photogrammetry engine for model construction
US7974714B2 (en) 1999-10-05 2011-07-05 Steven Mark Hoffberg Intelligent electronic appliance system and method
US6965397B1 (en) 1999-11-22 2005-11-15 Sportvision, Inc. Measuring camera attitude
US20020030692A1 (en) * 2000-09-08 2002-03-14 Arnfried Griesert Method for generating a picture in a virtual studio
US20060038962A1 (en) * 2004-08-19 2006-02-23 Seiko Epson Corporation Keystone correction using a part of edges of a screen
EP1628259A1 (en) * 2004-08-19 2006-02-22 Seiko Epson Corporation Automatic keystone distortion correction using a part of edges of a screen
USRE43721E1 (en) 2004-08-19 2012-10-09 Seiko Epson Corporation Keystone correction using a part of edges of a screen
US7347564B2 (en) 2004-08-19 2008-03-25 Seiko Epson Corporation Keystone correction using a part of edges of a screen
US7593560B2 (en) * 2006-11-30 2009-09-22 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of DNA molecules
WO2008066869A2 (en) * 2006-11-30 2008-06-05 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of dna molecules
US20080130971A1 (en) * 2006-11-30 2008-06-05 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of dna molecules
WO2008066869A3 (en) * 2006-11-30 2008-11-06 Canon Us Life Sciences Inc Systems and methods for monitoring the amplification and dissociation behavior of dna molecules
US8989466B2 (en) 2006-11-30 2015-03-24 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of DNA molecules
US20090324037A1 (en) * 2006-11-30 2009-12-31 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of dna molecules
US8306294B2 (en) 2006-11-30 2012-11-06 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of DNA molecules
US9732380B2 (en) 2006-11-30 2017-08-15 Canon U.S. Life Sciences, Inc. Systems and methods for monitoring the amplification and dissociation behavior of DNA molecules
US8170368B2 (en) * 2007-03-16 2012-05-01 Fujitsu Limited Correcting device and method for perspective transformed document images
US20080226171A1 (en) * 2007-03-16 2008-09-18 Fujitsu Limited Correcting device and method for perspective transformed document images
US8780280B2 (en) * 2010-09-16 2014-07-15 Seiko Epson Corporation Projector and control method for projector
US9240036B2 (en) 2010-09-16 2016-01-19 Seiko Epson Corporation Projector and control method for projector
US20120069177A1 (en) * 2010-09-16 2012-03-22 Seiko Epson Corporation Projector and control method for projector
US20170024861A1 (en) * 2014-04-24 2017-01-26 Panasonic Intellectual Property Management Co., Lt Vehicle-mounted display device, method for controlling vehicle-mounted display device, and non-transitory computer readable medium recording program

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