Abstract:
The invention concerns a method and a system for: (i) producing in a computer processing unit a flow of synthetic images, and (ii) tracing a scene by creating visual interactions between the synthetic image flow and at least one video image flow. The computer processing unit comprises: a motherboard, a graphics board for scene rendering and display, including a processor for accelerating 2D/3D processing, a work buffer and a texture memory, an acquisition means for acquiring in real time video images, in a video buffer. The specific rendering of the scene is carried out: by recopying the video buffer in a memory zone of the graphics board, by tracing the synthetic images in the work buffer.

Description:
PREAMBLE OF THE DESCRIPTION  
       [0001]     Domain involved, problem in question.  
         [0002]     The present invention concerns a method and a system permitting a user to mix synthetic images and video images in real time.  
         [0003]     More precisely, the subject matter of the invention is a method and a system enabling a user:  
         [0004]     (i) to produce in a data processing unit, composed of standard electronic circuits, a flow of synthetic images, and  
         [0005]     (ii) to trace a scene by creating visual interactions between the flow of synthetic images and at least one flow of video images.  
         [0006]     The solution of this problem presented by the invention permits improving the quality of the scene and to shorten the processing time without employing proprietary and expensive data processing units.  
       Prior Art  
       [0007]     An equipment according to the prior art is represented in  FIG. 1  which permits the achievement of the improved reality. This equipment includes; 
        a graphic work station STG,     a rack of the “chroma keyer” type RCK,     a rack of the “image delay” type RRI.        
 
         [0011]     The legends C and SV indicate respectively a camera and a video output.  
         [0012]     The graphic work station STG is used for the generation only of synthetic images. The graphic work statio STG is developed specifically or is a Silicon Graphics™ station. The synthetic images are generated on a uniform color background (key color).  
         [0013]     The “chroma keyer” type rack RCK is used for mixing the video image from the camera (C) with the synthetic image generated by the graphic station STG. The key color is replaced by the video image.  
         [0014]     The “image delay” type rack RRI is used to compensate for the processing time of the image generator.  
         [0015]     Drawbacks of the prior technology:  
         [0016]     Equipment of the prior art present problems in regard to price and image qualities and functionality.  
         [0017]     Problems in regard to price:  
         [0018]     The cost price of the equipment of the prior art is very high. In fact, the “image delay” rack RRI is a professional rack, the graphic station STG is a professional station. The previous solution according to the prior art is not carriable(it is made up of three separate modules: image generator/image delay/chroma key).  
         [0019]     Problems in regard to image quality and functionality:  
         [0020]     Visual interactivity between the video and the synthetic images is limited. In fact, at the output from the “chroma keyer” RCK the video is inserted in place of the key color. It is not possible to have reflections of the video on the synthetic images or vice versa. The video cannot be treated as a texture. For example, it cannot have reflection effects between the real images (video images) and the synthetic objects. The very principle of the “chroma key” can produce artefacts; it limits selection in the color palette of synthetic images, and makes the rendition of synthetic objects that have transparencies problematical.  
         [0021]     The performance of specific graphic stations is quickly exceeded by the performance of consumer graphic boards which are ever more powerful (graphic power of consumer equipment is doubled about every six months).  
         [0022]     The previous solution is expensive in terms of maintenance (the three units composing it involve a specific maintenance contract).  
         [0023]     The previous solution cannot operate in a portable computer; it is not mobile.  
         [0024]     The previous solution is constraining as regards time involved in adjusting all its parts.  
         [0025]     On processing of the video image is possible: 
        the video cannot be used to texturize locally any element of the virtual scene,     the video cannot be shaped (for example the correction of optical distortions is impossible),     no processing can be performed on the video (for example, processing of the chroma key type).        
 
       SOLUTION  
       [0029]     Process  
         [0030]     The data processing unit according to the invention, particularly of the “PC computer” type, comprises: 
        a mother board     a graphic board for rendering and displaying the scene.        
 
         [0033]     The meaning of scene in the sense of this invention is set forth below in connection with  FIG. 2 .  
         [0034]     The graphic board for rendering and displaying the scene comprises a processor for accelerating 1D and 3D processings, a working buffer “back buffer” and a texture memory.  
         [0035]     The data processing equipment also includes an acquisition means making it possible to acquire video images in real time in a video buffer. The acquisition means appears particularly in the form: 
        of a video acquisition integrated into the graphic board, and/or     of a video acquisition integrated into the mother board, and/or     of a video acquisition via a dedicated acquisition card (for example a Pinnacle™ card known by the name of PCTV).        
 
         [0039]     The method according to the invention includes the step of performing a specific rendering of the scene, 
        by copying the video buffer, upon each rendering of the scene, in a memory area of the graphic board,     by tracing the synthetic images in the said working buffer of the graphic board.        
 
         [0042]     According to a first variant embodiment of the invention, to carry out a specific rendering, preferably the method includes the following steps: 
        the step of copying the video buffer into the working buffer after each rendering of the scene,     the step of tracing the synthetic images in the working buffer.        
 
         [0045]     In the case of this first variant embodiment, when the video buffer includes interlaced video lines, to copy the video buffer, upon each rendering of the scene, into the working buffer, preferably the procedure includes: 
        the step of copying the even video lines, in a first rendering, then     the step of copying the odd video lines, in the following rendering.        
 
         [0048]     According to a second variant embodiment of the invention, to carry out a specific rendering the method includes, preferably, an initialization step prior to the specific rendering, consisting of creating a dedicated texture in the texture memory of the graphic board. The dedicated texture is of the size of the video buffer. The texture is dedicated for copying the video buffer into the texture memory.  
         [0049]     In the case of this second variant embodiment, the method furthermore includes: 
        the step of copying the video buffer into the dedicated texture,     the step of completely retracing the scene, using the dedicated texture to texture some of the polygons of the scene.        
 
         [0052]     In the case of this second variant embodiment, when the video buffer contains interlaced video lines, to copy the video buffer, upon each rendering of the scene, into the dedicated texture, preferably according to the invention the method comprises: 
        the step of copying the even video lines in a first rendering, then     the step of copying the odd video lines in the following rendering,     the step of applying a translation of the video buffer of more or less one half-line to the rendering of the scene.        
 
         [0056]     This translation of the video buffer is performed: 
        either by modifying the texture coordinates of the dedicated texture,     or by modifying the coordinates of the polygons textured by the dedicated texture.        
 
         [0059]     The image quality is thus improved.  
         [0060]     In the case of the first variant embodiment as in the case of the second variant embodiment, it is possible to copy the video buffer into the memory area of the graphic board by proceeding in two different ways.  
         [0061]     In the case of a first way, the means of acquisition includes a driver having a new video buffer for each new video image. Preferably according to the invention, in the case of this first way, the rendering of the scene is performed in synchronism with the presentation of each new video buffer.  
         [0062]     In the case of the second way, the acquisition means also includes a driver presenting a new video buffer for each new video image. However, in the case of this second manner of proceeding, preferably according to the invention the method comprises the following steps: 
        the step of filling a buffer memory with each new video buffer by employing a unit of performance (“thread”) of video capture,     the step of copying one of the video buffers contained in the buffer memory to the texture memory of the graphic board,     the step of performing the scene rendition asynchronously with respect to the presentation of each new video buffer.        
 
         [0066]     The method according to the invention permits improved graphic functionality in the designing of a scene mixing a video image with a synthetic image.  
         [0067]     Anti-Aliasing  
         [0068]     Preferably, according to the invention, the method includes the step of applying an anti-aliasing function in the designing of the scene. The ideas of anti-aliasing function will be described below.  
         [0069]     Transparency  
         [0070]     Preferably, according to the invention, the method includes the step of applying a transparency function during the designing of the scene. The ideas of transparency function will be described below.  
         [0071]     Correction of Optical Distortion  
         [0072]     Preferably, according to the invention, the method includes the step of applying non-linear distortions to the video buffer by texturing the polygons of the scene by means of the dedicated texture.  
         [0073]     It is thus possible to correct optical distortion of the video image.  
         [0074]     Real-time Processing of Video Images  
         [0075]     Preferably, according to the invention, the method includes the step of applying pixel shaders functions to the video buffer, permitting especially a chroma key type processing. The idea of pixel shaders and processing of the chroma key type will be described below.  
         [0076]     Environment Mapping  
         [0077]     Preferably, according to the invention, the data processing unit includes two means of acquisition, each having a video buffer. The method comprises the following steps: 
        the step of copying the video buffer of one of the acquisition means into a second dedicated texture of the graphic board,     the step of texturing at least a portion of the scene by using the second dedicated texture.        
 
         [0080]     It is thus possible to obtain real reflections on the synthesis objects.  
         [0081]     Video Delay  
         [0082]     Preferably, according to the invention, the method includes the step of slowing the copy of one of the video buffers contained in a buffer memory toward the texture memory of the graphic board.  
         [0083]     It is thus possible to delay the display of the video images with respect to the display of the synthetic images.  
         [0084]     System  
         [0085]     The invention likewise concerns a system enabling a user:  
         [0086]     (i) to produce in a data processing unit, composed of standard electronic circuits, a flow of synthetic images, and  
         [0087]     (ii) to design a scene, creating visual interaction between the synthetic image flow and at least one flow of video images.  
         [0088]     The solution of this problem makes it possible to improve the quality of the scene and to reduce the processing time, without making use of proprietary and expensive data processing units.  
         [0089]     The data processing unit according to the invention includes a processor, particularly of the common “PC” type. This processor comprises: 
        a mother board     a graphic board for rendering and displaying the scene.        
 
         [0092]     The rendering and displaying graphic board contains a processor for accelerating 2D/3D processings, a working “back buffer” and a texture memory.  
         [0093]     The data processing equipment includes an acquisition means allowing the acquisition in real time of video images in a video buffer. The acquisition means appears particularly in the form: 
        of a video acquisition means integrated into the graphic board, and/or     a video acquisition means integrated into the mother board, and/or     a means of video acquisition via a dedicated acquisition card.        
 
         [0097]     To perform a specific rendition of the scene: 
        the mother board furthermore contains a data processing means making it possible, upon each rendition of the scene, to copy the video buffer into a memory zone of the graphic board,     the 2D/3D processing accelerating processor includes tracing means for tracing designing the synthetic images in a memory area of the graphic board.        
 
         [0100]     In a first variant embodiment, preferably according to the invention, to carry out a specific portrayal rendition of the scene: 
        the data processing means comprise first copying means for copying, at each portrayal of the scene, the buffer video into the working buffer,     the 2D/3D processing accelerating processor comprises first computing means for tracing the synthetic images into the working buffer.        
 
         [0103]     In the case of this first variant embodiment, when the video buffer contains interlaced video lines, then preferably according to the invention, the first means for copying from the buffer video into the working buffer comprise: 
        first means for selecting and copying the even video lines, in a first rendition, then     second means for selecting and copying the odd video lines in the following rendition.        
 
         [0106]     In a second variant embodiment, to perform a specific rendition, preferably according to the invention, the data processing means comprise initialization means creating, prior to the specific rendition, a dedicated texture in the texture memory of the graphic board. The dedicated texture has the size of the video buffer. In the case of this second variant embodiment, the data processing means furthermore comprise second copying means for copying the video buffer into the dedicated texture, 
        the 2D/3D processing acceleration processor comprises second computing means for completely tracing the scene, using the dedicated texture for texturing certain polygons of the scene.        
 
         [0108]     In the case of this second variant embodiment, when the video buffer contains interlaced video lines, preferably according to the invention, the second means for copying from the video buffer into the dedicated texture comprise: 
        third selection and copying means for the even video lines in a first rendition, then     fourth selection and copying means for the odd video lines in the following rendition.        
 
         [0111]     The 2D/3D processing acceleration processor comprises third computation means in order to apply a translation from the video buffer of more or less one half-line in the rendition of the scene.  
         [0112]     This translation from the video buffer is performed: 
        either by modifying the texture coordinates of the dedicated texture,     or by modifying the coordinates of the polygons textured by the dedicated texture.        
 
         [0115]     Thus the image quality is improved.  
         [0116]     In the case of the first variant embodiment, as in the case of the second variant embodiment, it is possible to copy the video buffer in two different ways:  
         [0117]     In the case of the first way of proceeding, the acquisition means comprises a driver having a new video buffer for each new video image. Preferably, according to the invention, in the case of this first way of proceeding, the data processing means perform the rendition of the scene in synchronism with the presentation of each new video buffer.  
         [0118]     In the case of a second way of proceeding, the acquisition means comprises a driver having a new video buffer for each new video image. Preferably, according to the invention, in the case of this second way of proceeding, the said data processing means comprise: 
        transfer means for filling a buffer memory with each new video buffer, using a video capture performance unit (“thread”),     third copying means for copying a video buffer contained in the said buffer memory to the texture memory of the graphic board.        
 
         [0121]     The data processing means perform the rendering of the said scene out of synchronism with respect to the presentation of each new video buffer.  
         [0122]     The system according to the invention permits graphic functionalities when a scene is being scanned by mixing a video image with a synthesis image.  
         [0123]     Anti-Aliasing  
         [0124]     Preferably, according to the invention, the data processing means make it possible to apply an anti-aliasing during the designing of the scene.  
         [0125]     Transparency  
         [0126]     Preferably, according to the invention, the data processing means permit applying a transparency function during the scanning of the scene.  
         [0127]     Correction of Optical Distortion  
         [0128]     Preferably, according to the invention, the data processing means permit applying non-linear distortion to the video buffer by texturing polygons of the scene by means of the dedicated texture.  
         [0129]     It is thus possible to correct optical distortions of the video image.  
         [0130]     Real-Time Processing of Video Images  
         [0131]     Preferably, according to the invention, the data processing means permit applying pixel shader functions, permitting in particular a processing of the chroma key type.  
         [0132]     Environment Mapping  
         [0133]     Preferably, according to the invention, the data processing unit includes two acquisition means each having a video buffer. The data processing means permit copying the video buffer of one of the acquisition means into a second dedicated texture of the graphic board.  
         [0134]     The 2D/3D processing accelerating processor permits texturing at least a portion of the scene by using the second dedicated texture.  
         [0135]     It is thus possible to obtain real reflections on the synthetic objects.  
         [0136]     Video Delay  
         [0137]     Preferably, according to the invention, the data processing means permit slowing the copy of one of the video buffers contained in a buffer memory toward the texture memory of the graphic board.  
         [0138]     It is thus possible to delay the display of the video images with respect to the display of the synthetic images.  
     
    
     DETAILED DESCRIPTION  
       [0139]     Other characteristics and advantages of the invention will appear from reading the description of a variant embodiment of the invention, given by way of suggestive but not limiting example, and of  
         [0140]      FIG. 1  representing equipment of the prior art making it possible to make improvements to reality  
         [0141]      FIG. 2  representing an overall plan of a variant embodiment of a system according to the invention,  
         [0142]      FIG. 3  schematically showing the data processing means  26  in the case of another Variant embodiment,  
         [0143]      FIG. 4  representing schematically the 2D/3D processing acceleration processor  9  in the case of the variant embodiment shown in  FIG. 3 ,  
         [0144]      FIG. 5  representing schematically a variant embodiment in the case in which the acquisition means  12  appears in the form of a video acquisition integrated into the graphic board  8 ,  
         [0145]      FIG. 6  representing schematically a variant embodiment in the case where the acquisition means  12  is in the form of a video acquisition integrated into the motherboard  7 ,  
         [0146]      FIG. 7  schematically representing a variant embodiment in a case where the acquisition means  12  appears in the form of a video acquisition by way of a dedicated acquisition card,  
         [0147]      FIG. 8  schematically representing the copy algorithm of the video buffer  14  in the video output buffer (back buffer)  40  of the graphic board,  
         [0148]      FIG. 9  schematically representing the copy algorithm of the video buffer  14  in the texture memory  11  of the graphic board. 
     
    
       [0149]      FIG. 1  has been described above in the presentation of the prior art. Now  FIG. 2  will be described, which represents an overall plan of a variant embodiment of a system according to the invention.  
         [0150]     In  FIG. 2  there is represented a data processing unit  2  comprising: 
        a graphic board  8 ,     a motherboard  7      acquisition means  12  receiving a flow  5  of video images  13 ,     a hard disk  42  containing a scene  4 .        
 
         [0155]     The graphic board  8  comprises: 
        a 2D/3D processing acceleration processor  9  comprising first computing means  29 ,     a work buffer  10  receiving the flow  3  of synthetic images  16  from the 2D/3D processing acceleration processor  9 ,     a texture memory  11  comprising a dedicated texture  19 ,     a video output  39 ,     a video output buffer (back buffer)  40 .        
 
         [0161]     The motherboard  7  comprises: 
        data processing means  26  comprising first copy means  27  containing first selection and copy means  30 , [and] second selection and copy means  31 ,     a central memory  41  containing a scene  4  and polygons  20 ,     a buffer memory  23  comprising video buffers  14  containing even video lines  17  and odd video lines  18 ,     a driver  22 ,     an execution unit  24 .        
 
         [0167]     In another variant embodiment, the data processing means  26  include initialization means  32 , second copy means  33  comprising the third means of selection and copy  35 , [and] fourth selection and copy means  35  (see  FIG. 3 ). In the case of this variant embodiment, the 2D/3D processing acceleration processor  9  includes second computing means  34  (see  FIG. 4 ),  
         [0168]     The acquisition means  12  numbers the video signal  13  corresponding to the video images of the flow  5  (the video signal can be in the analog or numerical standard). The mother board receives this numbered flow in a video buffer  14  composed of pixels and stored in its memory. In the description, the video buffer  14  is also called the pixel buffer.  
         [0169]     A 3D scene  4  is a combination of elements: 
        3D objects composed of textures (2D image) and polygons  20  (3D geometry).     Light sources     Virtual cameras.        
 
         [0173]     The 3D scene  4  is stored on the hard disk  42  and is recopied into the central memory  41  of the motherboard  3 .  
         [0174]     To calculate a synthesis image  16 , the motherboard  7  copies the video buffer  14  and the textures of the 3D scene in the texture memory  11  of the graphic board  8  and sends to the latter all of the polygons  20  to be displayed, the light sources, [and] the camera. The specialized circuits (the 2D/3D processing accelerating processors  9 ) compute from these 3D data an image 2D in the work buffer  10  (back buffer). The content of the work buffer  10  is then transferred into the video output buffer  40  (front buffer) and the video output  39  to be used by the display device (television, monitor, projector) to display the image.  
         [0175]     The video buffer  14  is recopied into the dedicated texture  19  of the texture memory  11 . Since the dedicated texture  19  is part of the scene, it is possible to display its content according to the needs of the user. The following displays are mentioned as non-restrictive examples: 
        display of the dedicated texture  19  in the background to obtain a “full screen” video.     display of the dedicated texture  19  on a synthetic object included in the scene  4  to enrich the latter with a video in real time.        
 
         [0178]     Texturization is a technique that consists in drawing a polygon  20  in 3D with a texture (2D image) superimposed. For this purpose, each apex 3D is assigned a polygon  20  of 3D coordinates (texture coordinates) in the texture. It is possible to use several textures on the same polygon  20 . A set of texture coordinates for each texture is associated with the apexes.  
         [0179]     The texturization can be done with any type of 2D image, and therefore with the video buffer  14  which is a 2D image. A set of polygons  20 , texturized with the video buffer  14 , is treated like any object involved in the computing of the synthetic image  16 .  
         [0180]     A description will now be given of  FIG. 5  schematically represented a variant embodiment in a case where the acquisition means  12  appears in the form of a video acquisition integrated into the graphic board  8 .  
         [0181]     The data processing unit  2  contains a graphic board  8  equipped with an acquisition means  12 . The video image  13  is acquired in real time by the acquisition means  12  and then recopied into the video buffer  14 . The video buffer  14  is then recopied in two possible ways: 
        either to the work buffer  10 ,     or to the texture memory  11 .        
 
         [0184]     After this copy, the 2D/3D processing acceleration processor  9  performs a rendering of the scene  4  in the work buffer  10 . The work buffer  10  is transferred into the video output buffer  40  which makes it possible to update the video output  39 .  
         [0185]     Now a description will be given of  FIG. 6  which represents schematically a variant embodiment in a case where the acquisition means  12  appears in the form of a video acquisition integrated into the motherboard  7 .  
         [0186]     The data processing unit  2  contains a motherboard  7  equipped with an acquisition means  12 . The data processing unit  2  likewise contains a graphic board  8 . The video image  13  is acquired in real time by the acquisition means  12 , then recopied into the video buffer  14 . The video buffer  14  is then recopied in two possible ways: 
        either to the work buffer  10 ,     or to the texture memory  11 .        
 
         [0189]     After this copy, the 2D/3D processing acceleration processor  9  performs a rendering of the scene  4  in the work buffer  10 . The work buffer  10  is transferred to the video output buffer  40  permitting the updating of the video output  39 .  
         [0190]     A description will now be given of  FIG. 7  which represents schematically a variant embodiment in the case where the acquisition means  12  appears in the form of a video acquisition via a dedicated acquisition card.  
         [0191]     The data processing unit  2  contains an acquisition means  12  in the form of an acquisition card connected to the motherboard  7  (for example, a Pinnacle™ PCTV card. The data processing unit  2  likewise contains a graphic board  8 . The video image  13  is acquired in real time by the acquisition means  12 , then recopied into the video buffer  14 . The video buffer  14  is then recopied in two possible ways: 
        either to the work buffer  10 ,     or to the texture memory  11 .        
 
         [0194]     After this copy the 2D/3D processing accelerating processor  9  of the graphic board performs a rendering of the scene  4  in the work buffer  10 . The work buffer  10  is transferred into the video output buffer  40  permitting the updating of the video output  39 .  
         [0195]     A description will now be given of  FIG. 8  which schematically represents in block form the copying of the video buffer  14  into the video output buffer (back buffer)  40  of the graphic board. The blocks have the following meaning:  
         [0196]     Block  48 :  
         [0197]     START  
         [0198]     Block  50 :  
         [0199]     Initialization of the acquisition means  12 :  
         [0200]     Change to acquisition mode.  
         [0201]     Definition of the video input (e.g.: Svideo/PAL/NTSC  
         [0202]     Starting of the video acquisition.  
         [0203]     Block  52 :  
         [0204]     Initialization of the 2D/3D processing acceleration processor  9 :  
         [0205]     Definition of the type of output (e.g.: VGA or PAL or NTSC or DVI).  
         [0206]     Definition of graphic mode (full screen or window).  
         [0207]     Definition of the graphic resolution (e.g.: 800 by 600 at 32 bits per pixel).  
         [0208]     Definitial of the mode Z buffer (init. of 3D acceleration).  
         [0209]     Change to double buffer mode (creation of video output  40  and work buffer  10 ).  
         [0210]     Block  54 :  
         [0211]     Change of scene  4 :  
         [0212]     Loading of all 3D models from the hard disk  42 .  
         [0213]     Block  56 :  
         [0214]     RAZ of the Zbuffer.  
         [0215]     RAZ of the work buffer  10  (optional).  
         [0216]     Block  58 :  
         [0217]     Copying of video buffer  14  coming from the acquisition means  12  into the work buffer  10 .  
         [0218]     Block  60 :  
         [0219]     Tracing of scene  4  into the work buffer  10  performed by the 2D/3C processing acceleration processor  9 .  
         [0220]     Updating of video output buffer  40   
         [0221]     Block  62 :  
         [0222]     End program? 
         [0223]     Block  64 :  
         [0224]     THE END.  
         [0225]     A description will now be given of  FIG. 9  schematically representing in block form the copy algorithm of the video buffer  14  into the texture memory  11  of the graphic board.  
         [0226]     The blocks have the following meaning:  
         [0227]     Block  66 :  
         [0228]     START  
         [0229]     Block  68 :  
         [0230]     Initialization of the acquisition means  12 :  
         [0231]     Change to acquisition mode  
         [0232]     Definition of video input (e.g.: Svideo/PAL/NTSC)  
         [0233]     Block  70 :  
         [0234]     Initialization of the 2D/3D processing acceleration processor  9 ,  
         [0235]     Definition of type of output (e.g.: VGA or Pal or NTSC or DVI).  
         [0236]     Definition of the graphic mode (full screen or window).  
         [0237]     Definition of the graphic resolution (e.g.: 800 by 600 at 32 bits per pixel)  
         [0238]     Definition of the Zbuffer mode (init. 3D acceleration).  
         [0239]     Shift to double buffer mode (creation of the video output buffer  40  and work buffer  10 ).  
         [0240]     Initialization of the dedicated texture (creation of the dedicated texture  19  in the texture memory  11 , the dedicated texture  19  at the same number of lines and columns as the video capture buffer video  14 )  
         [0241]     Block  72 :  
         [0242]     Loading of scene  4   
         [0243]     Loading of all 3D models from the hard drive  42 .  
         [0244]     Block  74 :  
         [0245]     RAZ of the Zbuffer.  
         [0246]     RAZ of the work buffer ( 10 ) (optional).  
         [0247]     Block  76 :  
         [0248]     Copy of the video buffer  14  from the acquisition means  12  in the dedicated texture  19  included the texture memory  11 .  
         [0249]     Block  78 :  
         [0250]     Tracing of scene  4  into the working buffer  10   
         [0251]     Utilization of textures, including those that can be made of a texture (e.g., environment mapping, traced internal combustion engine he work buffer  10  as screen background, texturization of synthetic objects).  
         [0252]     Updating of the video output buffer  40 .  
         [0253]     Block  80 :  
         [0254]     End of program? 
         [0255]     Block  82 :  
         [0256]     END.  
         [0257]     Description of the anti-aliasing:  
         [0258]     Anti-aliasing is the filtering operation that permits reduction of the stair-steps on the edges of the polygons  20  due to the finite resolution of the synthetic image  16 .  
         [0259]     When anti-aliasing is applied, the color of the pixels on the edges of the object in the foreground is obtained by an operation of filtering between the pixels of the background objects and the pixels of the object in the foreground.  
         [0260]     The invention makes it possible to treat a textured object with the video as an element of the same nature as the other synthetic objects: the anti-aliasing functions therefore are applied in tracing the entire scene.  
         [0261]     Description of Transparency Effects  
         [0262]     The synthetic objects can contain transparent surfaces. If such an object is in the foreground in relation to a background object textured with a video, the texured video object will be seen through these surfaces.  
         [0263]     Description of Non-Linear Distortion:  
         [0264]     The method permits the application of non-linear distortion to the video, since the latter is stored in a texture mapped on polygons  20 . It is thus possible to distort the video image in real time to correct the optical distortions of the video camera. The lines at the edges of the image that appear to be curved can thus be straightened by pulling the video texture.  
         [0265]     For this purpose a regular mesh of polygons  20  is created on which a video texture is plated with texture coordinates describing a curve when the coordinates of the associated vertices evolve linearly.  
         [0266]     Description of “pixel shader” Processings,  
         [0267]     Particularly on the “Chroma Key.” 
         [0268]     The final color of a pixel is a combination between the color of this same pixel for the polygon  20  being traced and the color for the polygons  20  already traced. The color of a pixel of a polygon is a combination between the value of this pixel in the texture or textures associated with these polygons and the illumination of the polygon.  
         [0269]     The present-day graphic boards use a program (pixel shader) to perform this combination. This program is transferred into the graphic board  8  like the other 3D objects.  
         [0270]     The method of the invention pen-nits applying functions, known in themselves, of the “pixel shader” type, to the video image. This makes it possible particularly to employ algorithms of the “chroma-key” type on the video buffer  14 , or other image processings.  
         [0271]     The principle of the chroma key consists in replacing in an image all the points of a given color with points from another video source. Sometimes this technique is called “blue screen.” A description is provided below of a simple chroma-key algorithm. For each pixel of the video: 
        its color is entered in the space YUV,     the distance of this color is calculated in relation to a reference color, ignoring the coordinate Y (the luminance),     if the distance is less than a predetermined threshold the pixel is made transparent; otherwise it is displayed normally.        
 
         [0275]     Description of Environment Mapping  
         [0276]     Environment mapping is a technique that simulates reflective surfaces without using ray tracing (unusable in real time). The technique applies a special texture containing an image of the scene surrounding the object on the object itself. The result obtained is an approximation of the appearance of a reflective surface, without requiring too much computing power.  
         [0277]     The method of the invention, generalized to the use of two acquisition means  12  (two acquisition cards) permits using one of the two acquisition means  12  (one of the two acquisition cards) to copy the buffer video  14  associated with this card in the memory of a texture  11  which will serve as a mapping of the environment when objects of the texturized scene are traced with this texture. This particularly permits obtaining real reflections on these synthetic objects.  
         [0278]     The other acquisition card is used to copy its video buffer  14  to the memory of a texture displayed in the background of the synthetic objects on which there are reflections.  
         [0279]     Description of a Buffer Memory  23   
         [0280]     The buffer memory method permits slowing the display of the video images.  
         [0281]     N video images are stored in memory.  
         [0282]     The buffer memory method permits slowing the display of video images. The buffer memory  23  operates on the following principle: the buffer memory  23  can store N video buffers  14 . These video buffers  14  correspond to the video images  13  acquired by the acquisition means  12  during the cycles N, (N- 2 ), (N- 2 ), (N- 3 ), etc . . . In cycle N, the method can decide to use the video buffer  14  acquired at the cycle (N- 2 ), which in this case results in a slowing of the video images displayed by the video output  39  by 3 cycles. Generally, by this process, up to N delayed images can be introduced.  
         [0283]     Advantages of the Claimed Solution over the Prior Art  
         [0284]     Now the advantages of the method and system of the invention over the prior art will be explained: 
        The method and the system of the invention permit an improvement of the quality of the images: number of polygons, shadowing, texturizing, transparency, reflections and anti-aliasing.     The method and the system of the invention make it possible to achieve in real time the effects of video texturization, that is, the texturization of synthetic objects, not with a single static image, but with a live video.     The method and the system of the invention make it possible to achieve dynamic environment mapping effects, that is, the possibility of surrounding the synthetic objects with an environment map that is not static but is the video itself. This opens the door to surprising effects, particularly when the synthetic objects have as reflective a surface as a mirror.     The method and the system of the invention permit achieving everything that is possible to do classically with static textures, but now with one or several live video sources.     The method and the system of the invention permit carrying out a video image processing by the technology of pixel shaders (particularly processing of the chroma key type.     The method and the system of the invention permit slowing video images without an external rack.     The method and the system of the invention permit a reduction of the system&#39;s response time since all of the processings are internal in the same machine (the processing times of several processing units do not accumulate as internal combustion engine he prior art).     The method and the system of the invention permit the use of materials produced in large quantity at low cost.     The method and the system of the invention do not require electronic proprietary developments (hardware): they permit ease of maintenance (mother boards of the generally available PC, consumer graphic boards, consumer video acquisition cards).     The method and the system of the invention can work with a single computer (standard PC case), portable computer, or industrial rack PC).     The method and the system of the invention can operate in real time: the video images are generated directly. It is thus possible to eliminate the post-production costs (no time of several hours spent for a few seconds of video images).     The method and the system of the invention can be shipped. The method and the system can operate on compact industrial PC boards (military or naval or dangerous areas).     The method and the system of the invention can operate on hardened material (for industry, military).     The method and the system of the invention can follow the development of performances of accelerating graphic boards with the minor task of updating the software: use of standard graphic libraries (DirectX or Open     The method and the system of the invention can easily be moved (mobility) and quickly installed where it will be used.     The method and the system of the invention can run on a portable computer equipped with a video input (e.g.: DV input).        
 
         [0301]     Industrial and commercial applications of the method and system according to the invention.  
         [0302]     Industrial applications internal combustion engine he audiovisual field (motion pictures and video).  
         [0303]     The method and the system of the invention can particularly be used for audiovisual productions shot on line or under on-line conditions: 
        virtual sets in real time (display of presenters in virtual settings).     special effects in real time (e.g., particles, explosions, distortions in real time)        
 
         [0306]     The method and the system of the invention can be used especially in the advertising field (e.g., virtual products in real settings).  
         [0307]     The method and the system of the invention can be used in order to overlay virtual objects in a telecast and to create interaction with a live presenter (talkshows, sporting events, television sales, news, weather forecasts, medical broadcasts).  
         [0308]     The method and the system of the invention can be used in doing “avatars,” virtual personalities in real settings in real time.  
         [0309]     The method and the system of the invention can be used in making real-time visualizations for motion pictures (control of special effects at the site of the shooting).  
       INDUSTRIAL APPLICATIONS IN THE INDUSTRIAL FIELD  
       [0310]     The method and the system of the invention can be used in the manufacturing field (enrichment with real images to guide manual operations and inform the manufacturer during production).  
         [0311]     The method and the system of the invention can be used in the maintenance field (enrichment with real images with supplemental information to optimize maintenance schedules, real-time guide for emergency repairs).  
         [0312]     The method and the system of the invention can be used internal combustion engine the military (virtual targets, virtual threats, explosions, infantry, vehicles).  
         [0313]     The method and the system of the invention can be used in simulations (simulated atmospheric or environmental phenomena mixed with real props, testing of virtual prototypes, virtual vehicles).  
         [0314]     The method and the system of the invention can be used in the field of video games (real players visualized in a video game, or virtual elements such as persons, vehicles integrated into real images).  
         [0315]     The method and the system of the invention can be used: 
        in the automotive field (virtual vehicles on real roads).     in the field of architecture (visualization of virtual buildings in real landscapes).     in the field of real-time driving: display of data to direct a pilot or a conductor.        
 
         [0319]     Applications in the Marketing or Communication Field  
         [0320]     The method and the system of the invention can be used in conducting market studies: display of products not yet actually made, in real situations (e.g.: new mobile GSM, new vehicle).  
         [0321]     The method and the system of the invention can be used to make interactive images in shops or business centers.  
         [0322]     Industrial applications in the field of information technology.  
         [0323]     The method and the system of the invention can be used in video conferences: visiophone with possibility of inserting and interacting with virtual objects.  
       INDUSTRIAL APPLICATIONS IN THE LEISURE FIELD  
       [0324]     The method and the system of the invention can be used in amusement parks: visual animations in real time (e.g.: interactive mirrors).